THE MAGAZINE OF THE GLOBAL BBR NETWORK OF EXPERTS

North extremitiesRock anchors secure KjøllefjordWindProject, Northern Norway

World LNGconsumption soarsPost-tensioning technology meetsdemand for storage

Speedy solutionPT systems expedite Shopping CentreExpansion in Salzburg

Second longest &environmentally friendlyStay cables suppport the Green Bridge,Brisbane, Australia

MSS helps Bangkok beatcongestionIndustrial Ring Road Project,Thailand

www.bbrnetwork.com First Edition 2007

BBRVT International Ltd is the Technical Headquarters and Business Development Centre of the BBR Network, located in Switzerland.The Shareholders of BBRVT International Ltd are: BBR Holding Ltd (Switzerland), subsidiary of Tectus Group (Switzerland); BBR Polska Sp.z.o.o. (Poland), subsidiary of BBR Holding Ltd (Switzerland); BBR Pretensados y Técnicas Especiales, S.L. (Spain), member of the FCC Group(Spain); KB Spennteknikk AS (Norway), member of the Kongsvinger Betongindustri Group (Norway);VORSPANN-TECHNIK GmbH & Co.KG (Austria / Germany), member of the Porr Group (Austria).

BBR is recognised as the leading group of specialised engineering contractors in the

field of post-tensioning, stay cable and related construction engineering. The innovation

and technical excellence, brought together in 1944 by its three Swiss founders –

Antonio Brandestini, Max Birkenmaier and Mirko Robin Ros – continues, more than 60

years later, in that same ethos and enterprising style.

From technical headquarters in Switzerland, the BBR Network reaches out around the

globe and has at its disposal some of the most talented engineers, technicians and the

very latest internationally approved technology in the world.

The Global BBR NetworkWithin the Global BBR Network, established traditions and strong local roots are

combined with the latest thinking and leading edge technology. BBR grants each local

BBR Network member access to the latest technical know-how and resources – and

facilitates the exchange of information on a broad scale and within international

partnering alliances. Such global alliances and co-operations create local competitive

advantages in dealing with, for example, efficient tendering, availability of specialists and

specialised equipment or transfer of technical knowledge.

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Activities of the NetworkAll BBR Network members have established and strong local connections in their

respective regions.They are all structured differently to suit the local market and

offer a variety of construction services, in addition to the traditional core

business of post-tensioning.

BBR TechnologiesBBR technologies have been applied to a vast array of different structures

– such as bridges, buildings, marine structures, tanks, towers – and used in all

types of geotechnical applications.The BBR brands and trademarks – CONA,

CMM, BBRV, HiAm, DINA and SWIF – are recognised worldwide.

The BBR Network has a track record of excellence and innovation – with

thousands of structures built using BBR technologies.While BBR’s history goes back over

60 years, the BBR Network is focused on constructing the future – established traditions

are blended with the latest thinking and leading technology.

THE MAGAZINE OF THE GLOBAL BBR NETWORK OF EXPERTS

North extremities Rock anchors secure Kjøllefjord WindProject, Northern Norway

World LNG consumption soarsPost-tensioning technology meetsdemand for storage

Speedy solutionPT systems expedite Shopping CentreExpansion in Salzburg

Second longest &environmentally friendlyStay cables suppport the Green Bridge,Brisbane, Australia

MSS helps Bangkok beatcongestionIndustrial Ring Road Project,Thailand

www.bbrnetwork.com First Edition 2007

Bruno ValsangiacomoChairmanBBRVT International Ltd

Marcel PoserCEOBBRVT International Ltd

Talking technical 1

BRIDGESMSS helps Bangkok beat congestionINDUSTRIAL RING ROAD PROJECT,THAILAND 5Postcards from the countrysideMILOWKA FLYOVER, POLAND 8Link to the mainlandHUFTARØY-HUNDVÅKØY BRIDGES, NORWAY 9Travelling formworkBATANG BARAM BRIDGE, MIRI SARAWAK, MALAYSIA 9Launching in lowest place on EarthDEAD SEA PARKWAY ROAD PROJECT, JORDAN 10Flying over, under and around JeddahKING ABDULLAH ROAD, JEDDAH,KINGDOM OF SAUDI ARABIA 11

Pioneering in PolandOLSZTYN BRIDGE SLIDE 12Incremental launchingat Las PiedrasVIADUCTO ARROYODE LAS PIEDRAS, SPAIN 13

BUILDINGSBeautiful challenge down under!PEPPERS PIER RESORT, HERVEY BAY,QUEENSLAND,AUSTRALIA 16Competitive alternative designMTC MULTIFUNCTIONAL SHOPPING CENTRE,CAKOVEC, CROATIA 17Europe’s largest retail centreWHITE CITY SHOPPING DEVELOPMENT, LONDON 17

How a Moveable ScaffoldSystem helped to keep trafficmoving during constructionin one of the world’s mostcongested cities. contents

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This first edition of CONNÆCT, theMagazine of the Global BBR Networkof Experts, brings inspiring and

informative stories about constructionachievement which has been realised withBBRTechnologies and the people of the BBRNetwork throughout the world.With environmental and financial expectations to the fore,international communities are demanding ever moretechnological advancement and skill from engineers andtechnicians. Within the Global BBR Network, we are proud tohave a pool of the most talented professionals, as well as awide range of leading edge products and services, all focusedon meeting those challenges by creating innovative solutions.

Knowledge management and knowledge sharing is key tocontinued technological progress. Our people have access tothe very latest internationally approved technology andinformation and have the opportunity to share and exchangeinformation within the BBR Network. By having a strongglobal dialogue within the construction technology arena, theBBR Network is at the very forefront of the constructionindustry and will always be a step ahead.

BUILDINGS CONTINUED

Massive milk powder storeSTOREHOUSE FLOOR IN NEW ZEALAND 18Speedy solutionSALZBURG SHOPPING CENTRE EXPANSION 19Building the little butterflyMULTIFUNCTIONAL RESIDENTIAL BUILDING,SLOVENIA 20Prestigious residential developmentAL NUAIMIAHTOWERS, AJMAN, UAE 21Taking the loadFRUIT JUICEWAREHOUSE FLOOR, POLAND 21

TANKS & SILOSWord LNG consumptionsoarsTECHNOLOGY MEETSDEMAND FOR STORAGE 22UK’s largest civils packageSOUTH HOOK LNGTANKS,PEMBROKE DOCK,WALES 24Adaptable techniqueGASCO LPGTANKS,RUWAIS, UAE 25

Floating terminalADRIATIC LNGTERMINAL, SPAIN – ITALY 26LNG market grows in SpainFROM BARCELONATO CARTAGENA, SPAIN 26Innovation continues in MuncihGUT GROSSLAPPENWASTEWATERTREATMENT PLANT,MUNICH, GERMANY 27State-of-the-art siloMELBOURNE CEMENT FACILITY,VICTORIA, AUSTRALIA 29

SPECIAL APPLICATIONSNorthern extremitiesKJØLLEFJORDWIND PROJECT, NORTHERN NORWAY 31Safely meeting productionMINING OPERATIONS, AUSTRALIA 32Load handling protects façadesEXTENSION OF METRO STATION, MADRID, SPAIN 32New underpass for India’s silicon valleyYELAHANKA UNDERPASS, BANGALORE, INDIA 33

STAY CABLESStaying powerLEGENDARY BBR STAY CABLE TECHNOLOGY 34Unlocking the town centrePONT DE LA FONDERIE, MULHOUSE, FRANCE 36Synchronised truckingLOADTESTING, SLOBODA BRIDGE,SERBIA 36Second longest &environmentally friendlyTHE GREEN BRIDGE, BRISBANEAUSTRALIA 37BBR triumph on bowstringarch bridgeNAVIA RIVERVIADUCT,NORTHERN SPAIN 40Time and tide wait for noman!STEEL ARCH BRIDGETO BUNTINGISLAND, KEDAH, MALAYSIA 42

MMRStrengthening innovationDEVENTER BRIDGE, OVERIJSSEL,THE NETHERLANDS 45

Seismic strengthening withBBRVUSHIGASEWATER RESERVOIR,JAPAN 47Repairs in live trafficROAD BRIDGE UPGRADINGPROJECT, SINGAPORE 48Raising the roofALL ENGLAND LAWNTENNIS &CROQUET CLUB 49Unique challengesHUNTLY POWER STATIONUPGRADE, NEW ZEALAND 50

LANDMARK STRUCTURESRealising dreams around the worldTATARA BRIDGE, JAPAN 51The world’s longest bridgeBAHRAIN CAUSEWAY 53

BBRWorldwide Directory 2007 56

contentscontinued

At Austria’s highly successful Europark shoppingcentre, BBR post-tensioned flat slab technologydelivered what the client wanted and reducedconstruction time.

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A look at the market place andhow construction technologyhas contributed to meetingincreased consumer demandsfor natural gas – on land andoffshore.

Completed at the end of2006 and the second longestcable stayed bridge inAustralia, Brisbane’s GreenBridge – which is closed toprivate vehicles – issupported by BBR CONAstay cable technology.

Innovative application ofBBR external post-tensioning has strengthenedtwin motorway bridgesnear Deventer in theNetherlands.

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1CONNÆCT

Marcel Poser, CEO of BBR VT International Ltd, answers some leadingquestions about European Technical Approvals, the BBR product rangeand the Global BBR Network, whilst sharing some thoughts about the

recent past and looking into the future. �

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Past, presentand future

2 CONNÆCT

Why is European TechnicalApproval (ETA) soimportant?Well, you have to understand the history of these things to reallyappreciate the value of ETA today. In the past, there were a lot ofnational approvals for technical products – some were very detailedas a result of local experience and others were not so detailed. Somecountries adapted and adopted specifications running in othercountries. But the net result was that systems were not easilycomparable internationally because of the differing requirements ofthe various national certification and approval processes.In effect, what has been created within the European Approval forPost-tensioning Kits is an “international passport” – the most up-to-date method of comparing like-with-like, from which it is clear exactlywhat specifications your product fulfils. ETA provides a clear,independent review, testing, Quality Assurance and auditing system forthe componentry. Every product is tested to the same standardsand, afterwards, an independent auditor ensures that what you deliverto and install on site fully complies with what you have actually tested.But more than this, ETA delivers a “recipe book” for designers onhow to use the system, as well as a gold-plated guarantee – the CELabel or Certificate of Conformity – of the quality and suitability ofthe product which gives confidence to owners of the structures towhich the system is applied.

How do you get ETA?

request more tests or seek further clarification. Only when this wholecycle has been successfully completed do you get European TechnicalApproval for your product or system. Full details of the ETA for theBBRVT CONA CMX range can be downloaded from our website –www.bbrnetwork.com.

BBR Technologies have national approvals and are well established and proven in therespective markets, however in the last twelve months the most significant accreditation inthe history of BBR has been for a completely new set of products – the BBRVT CONACMX range.

The new BBRVT CONA CMX range was launched at the 2006fib Congress in Naples.

The procedure can be a lengthy process because it requires anumber of stages and it thus requires a substantial investment – inboth time and money – on the part of the applicant!Guidance for the whole process is contained within ETAG 013 –Guideline for European Technical Approval of Post-Tensioning Kits forPrestressing of Structures – which details a clear set of testingprocedures which have to be fulfilled to obtain ETA. These includestatic tests, fatigue tests, load transfer, electrical resistance, cryogenictests and so forth.Throughout Europe, there are a number of laboratories which arecertified to conduct the testing process in accordance with the ETAGspecifications. Once completed, an approval body then evaluates thetest results, drawings and the complete system. Next, the whole setof information is sent to the “European circulation” – to all memberstates of the EU. These are designated specialists who review andcomment on the application – or indeed have the authority to

So, what is the new BBR VTCONA CMX range?The BBRVT CONA CMX is a new range of post-tensioning systems.

So far we have ETAs for:

• CONA CMI – Internal Bonded Post-tensioning System

• CONA CMM – Unbonded Post-tensioning System

In a way, you could say that this range was just like any other system

– except that we have gone a stage further. Instead of adapting an

old system to conform to new requirements, our engineers have

created totally new systems.

If you compare, for example, the CONA CMI system with other

similar approved systems, you would see that – technically – we really

do have the competitive advantage. Specific features of the new

system include:

• 20-40% less space needed in the anchor zone – thus, less

concrete, slimmer structures, less eccentricity in the anchors

• significantly lower concrete strength prior to stressing – thus,

shorter construction cycles

• less reinforcement in the anchor zone – thus, cost and time savings

Furthermore, the environment in which we live has changed

significantly and we now have to consider issues, such as increased

corrosion from pollution, when designing a product from a durability

viewpoint – and the needs of more advanced technical inspections of

a structure during its lifetime.

3CONNÆCT

How did this new productcome about?The process really started several years ago, when we first discussedthe possibility of producing something new. It takes a long time toconsider the needs of various markets – it’s all very well developingsomething on paper, but we wanted to make sure we understoodwhat those needs really were and then to deliver a solution whichmet these requirements, along with those of ETAG!We had a committed team of engineers who spent endless hoursworking on this development – Michael Schreiner, Piotr Krawczonek,Manfred Damoser, Juan Manuel Linero and Robert Danzl – and theywere not afraid of pushing back the technological boundaries inoptimising our new systems. They took all of the knowledge we havegained over the past 60 years and combined it with feedback fromaround the world, about what our Network members and theirclients need, to produce a completely new system. The end result isa high quality, up-to-date product which will ensure that the BBRNetwork is one step ahead of the pack in being able to deliver asuperb technological solution.

Why go to the trouble andexpense of creating a newproduct?OK, we could have taken any old system and modified it to meet therequirements, but we have taken this opportunity to respond to themarket with something truly state-of-the-art. We wanted to go theextra mile.Once in a while you need to create something completely new. It’s abit like that old car you bought ten years ago – whilst at the time itwas the highest possible spec, the new car you can buy today givesyou the benefit of all the technological advances in the interveningyears. Of course, you could adapt the old car, but so much haschanged – in terms of environmental influences and manufacturingtechniques – that it will never really have that leading edge technologyseamlessly fused into it – post-tensioning products are just the same.

When can the BBRNetwork start using thenew product?It’s available immediately in Europe – and the EC requires theseproducts to be used. In fact, it is available to the whole BBR Networkworldwide and our commitment to the highest quality productsmeans that there will be a high level of demand for constructionprojects all around the world in the short-to-medium term.

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PT SpecialistCompanyThe installation of Post-tensioning Kits has to beperformed by certifiedcompanies. For a completelist of all countries whereBBR certified PT SpecialistCompanies can be found,please visit the BBRWebsite:www.bbrnetwork.com

BBRVT CONA CMM– Unbonded Post-tensioning System

BBRVT CONA CMI– Internal BondedPost-tensioning System

How do BBR Networkmembers learn how to usea product?Within BBR, we are committed not only to selling components, butalso to the appropriate installation of our products – in fact, this is asimportant as the quality of the product itself. We certify all of ourNetwork members – annually – as PT Specialist Companies. Wearrange internal training sessions which ensure that the systems areinstalled in the correct way – it makes no sense to have the bestsystem if it’s poorly installed. �

4 CONNÆCT

If there is an implementation of a specific application, all members areencouraged to benefit from this experience by sending technicians tothat site so that they can observe and learn. Equally, members haveaccess to information and other members – that’s really the beauty ofsuch an active network, as knowledge can be transferred internallyand with great ease.At least once a year, we organise a global media conference – whereknowledge exchange happens on a broad scale. In 2006, represen-tatives from the whole Global BBR Network met in Dubai. Themeeting took place at the Jumeirah Emirates Towers where, some 16years earlier, BBR Network member Structural Systems had beenheavily involved! This year, we are looking forward to getting the BBRNetwork together at our Global BBR Conference in Singapore.Recent months have seen some excellent collaboration betweenNetwork members. There has been great work between teams fromthe UK and Spain in the transfer of specialist skills related to LNGtank construction projects. Meanwhile, skills in flat post-tensioning forheavy load slabs have travelled from Australia to New Zealand andthen around the globe to Poland. Cable stayed bridge constructionhas prompted close liaison between Network members in Spain andAustralia, while co-operation between the teams in Jordan and Saudi

Arabia has supported the construction of the Jamarat Ramp Bridgesproject, in Mina, just to the east of Mecca.It is not just knowledge which is passed around the world, but alsothe more tangible things – like equipment and tooling – whereindividual investment would simply not be not justified.This strength of know-how, combined with excellent products andthe tools for the job, means that every Network member has theopportunity to tender for any type and size of project – in the secureknowledge that they can rely on the experience of the entireNetwork, particularly for the eventual execution of the work. TheBBR Network enjoys a great competitive advantage and ensureseffective usage of equipment and specialists.

What’s on the cards for thenext twelve months?Looking at projects we are likely to be involved with throughout theworld, there will certainly be some exciting new schemes in theenergy sector, including more LNG tanks and wind farms, as well assome high-speed railway systems – plus further residential andindustrial development projects, particularly in Eastern Europe.In Spain, a landmark project will be getting underway – a cable-stayedbridge in Valencia, designed by world famous architect, SantiagoCalatrava. Meanwhile, the first cable stayed bridge in New Zealand –the Ormiston Road Bridge in Auckland – will be taking shape andusing BBRTechnology.Within BBR, we are always looking for complementary systems foruse in specific applications – we never stop studying the market tosee where there’s a need for a new system. Without revealing toomuch too soon, we are currently considering energy applications –windmills, LNG, nuclear – as part of our ongoing developmentprocess and commitment to a high level of quality and inspectability.As far as the BBR Network is concerned, over last couple of years ithas expanded significantly – we now have a presence in almost 50countries. In the next few years, we will have our eyes firmly focusedon continents where we still see potential – watch out for someannouncements in the very near future!

The 2006 Global BBR Network conference took place in Dubai –at the Jumeirah Emirates Towers where, some 16 years earlier, BBRNetwork member Structural Systems had been heavily involved!

First cable-stayed bridge inNew Zealand goes BBR –artist’s impression ofOrmiston Road Bridge.

5CONNÆCT

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MSS helps BangkokBEAT CONGESTION

Industrial Ring Road Project,ThailandBBR Construction Systems Singapore’s decision to use a Moveable Scaffold System (MSS),

during their contract to build part of the massive Industrial Ring Road (IRR) project, helped to keeptraffic moving in and around Bangkok while construction work was underway.

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6 CONNÆCT

Span length varies from 36m, to amaximum of 50m for the river crossing. Pierheight gradually increases from theabutment area up to a maximum height of45m above ground level at the interchange.

The width of the viaduct is 23m andconsists of a twin box girder whichgradually widens to 35m at the bifurcationarea, with two additional single box girdersat both sides.

PROJECT OVERVIEWThe project comprises two cable-stayed bridges –back-to-back, over a bend in the Chao PhrayaRiver downstream of Bangkok – with main spansof 398m and 326m respectively, as well as almost4000m of approach bridges and viaducts.The massive scale of the scheme and the need tocomplete it within a relatively short period oftime, dictated that the project should be dividedinto three contracts:• Contract 1 for the Southern Area• Contract 2 for the Northern Area• Contract 3 for theWestern Area.

BBR SCOPE OF WORKSBBR Construction Systems Singapore wasawarded the contract for construction of thesuperstructure works for part of Contract 3which comprised a 1368m long approach bridge,with 31 spans (PiersW32 –W1).The Company’s scope of works included thedesign, fabrication and operation of the MSS,formwork, laying of reinforcement, post-tensioningand concreting works.

The Industrial Ring Road scheme started as a Royally Initiated Project which wasfocused on solving the problems caused by the tremendous volume of traffic,both within the city centre and the surrounding areas.The objective was toalleviate traffic congestion, resulting from freight transportation, by providing new

bridges to link Bangkok Port with Pu Chao Saming Phrai Road to the South, Suksawat Roadto theWest and Rama III to the North.

7CONNÆCT

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CONSTRAINTOne of the major constraints in thispart of Contract 3, was that duringconstruction, all major roads had tobe kept open at all times – and thiswas a contractual requirement.Hence the MSS (MovableScaffolding System) method wasthe preferred choice forconstruction of the viaduct.Together with its Consultant, BBRSingapore designed, fabricated andoperated this MSS – 1600t ofstructural steel – over the entirelength of this approach bridge.

Facts & figuresThe superstructure of the viaduct,including the crossheads, consisted ofapproximately 30,000m3 of concrete,5900t of steel reinforcement and 1200t of0.6" diameter pre-stressing strands.Thepost-tensioning system used here was BBRCONA.The optimum cycle time achieved perspan using the MSS was 15 days, withabout 110 workers deployed during thepeak period.The team completedContract 3 in May 2006 – after a 3-yearconstruction contract. �The Moveable Scaffold System

This Movable Scaffold System (MSS) was designed to handle not only thelongest span of river crossing (50m), but also to tackle the bifurcation area,starting from Pier

W12 to W4.� PierW28 to PierW12

These locations were relatively straightforward as the width of the box girder remainedconstant throughout.

� PierW12 to PierW9From Pier W12 onwards, the width of the box girder gradually increases from 23m – to35m. At this point, the gantry arms were extended to cover the enlarged width of theviaduct.

� PierW9 to PierW4Here, two additional single boxes were connected to the slip ramps constructed by others.

� PierW4 to PierW1At Pier W4, the slip ramps curve away from the approach bridge.These slip ramps wereconstructed by others and were completed before the MSS arrived at this location.Therefore, in order to launch past Pier W4, the team completed construction of theprevious span, then lowered the side arms and the bottom platform and disconnectedthem from the hanger bars. The lowered members were then shifted to the next span byusing trailers. Next, the gantry was launched to the next span, the lower platforms wereraised and re-attached to the hanger bars.

TEAM &TECHNOLOGY

� OWNEROwner Public Works Department,Ministry of Interior, Thailand

� CONTRACTORKajima-Tokyu-Unique Joint Venture

� DESIGNEREpsilon Company Ltd, NorconsultCivil Engineering Co Ltd and MottMacdonald Ltd

� TECHNOLOGYBBR CONA internalBBR CONA flatMoveable Scaffold System (MSS)

� BBR NETWORK MEMBERBBR Construction Systems Pte Ltd(Singapore)

8 CONNÆCT

Road construction is avery hot topic inPoland.And safe,

collision-free traffic meansnew viaducts, flyovers andbridges. Depending ondestination, landscape and –last but not least – theowner’s expectation, varioustechnologies are at thedisposal of the designer.Thespecialist constructiontechniques, employed on thischallenging flyover project, aredescribed by site managerPiotr Stasyk of BBR Polska.

Our involvement in theconstruction of the flyover inMilowka – on Expressway S-69between Bielsko-Biala andZwardon – was substantial.

SPECIALIST WORKSThe project called for analternative design, application ofthe free cantilevering method,installation of 10 RESTONbearings (4300-20,000kN),installation and servicing ofcantilevering carriers,prestressing, BBR CONAexternal and internal cables, aswell as assembly and installationof twoTENSA Grip expansion

joints. A large range of specialistworks within the scope of onecontract is a logistical advantage.It allows us to optimise the timeresulting from the week-by-weekrhythm which is offered by thefree cantilevering method.

THE TERRAINThe flyover was situated in amountainous landscape.The construction site waslocated on a slope with aconsiderable incline.To level it,soil had to be brought in at thevery beginning, so that assemblyplaces, which were in any casevery limited in size, could beorganised.The approach to the site was amountain road with obviouslevel differences, making efficienttransportation difficult –especially after rain or during thewinter. Extreme conditions inour “backyard” – assembly andstorage places and roads – oftendictated the way tasks wereexecuted or the kind ofequipment used.

In the middle of the site, therewas a gorge – the main spancarriers were dismantled rightabove it – on this occasion,ordinary blocks had to be usedfor lifting during most of theworks.

EXTREME WEATHERThe weather provided somedistractions, too. After anintense snow fall, we had to findthe carriers first and then clearthem of snow before the actualwork started. After it rained, thesite turned into a muddy slide –impassable for heavy machineswithout the help of specialdevices.This was a commonoccurrence at Milowka.The shape of the structure isquite special too – concretehorizontal arch, with transverseand longitudinal inclination, 7% inthe case of the latter. In fact,there were enough complicationsfor several projects! Despitethat, completion of the workswas on target and prestressingwas completed on programme.

The balanced cantilever method is oftenappropriate and cost-effective for theconstruction of long spans where bridge

height, topography, or geotechnical conditionsrender the use of conventional falseworkuneconomical.

symmetrically from pier tables in segments ranging between 3 and5m in length. The construction sequence for a given segment consistsof the following steps:� Prestress the previously cast segment� Advance formwork travellers to their new position� Anchor travellers to the newly prestressed girder end and adjust

formwork� Place reinforcing steel, couple new tendon ducts with empty ducts

in the completed portion and pull prestressing steel into ducts� Cast the new segmentThe economical range of span lengths for cast in situ cantileverconstruction begins at roughly 70m and extends to beyond 250m.For long spans, the ratio of falsework and formwork cost to totalsuperstructure cost ranges between 25% and 35% , independent ofbridge height and topography. This represents a considerable savingover conventionally cast in situ bridges for which ratios of40% are typical.

TECHNICAL INSIGHT

Balanced cantileverconstruction

Cost-savings are achieved partly due to the construction method andpartly due to the structural system. Previously cast portions of thesuperstructure can immediately be used to support the constructionof new segments, making possible the use of short, economicalformwork travellers. Formwork is adjustable and can be reused manytimes. The regular repetition of identical tasks for the construction ofeach of the segments substantially reduces the ratio of labour coststo material costs. The use of short segments makes possible aneconomical prestressing layout that closely matches the momentdiagram. In classical cantilever construction, cantilevers are built out

Postcards from thecountrysideMILOWKA FLYOVER, POLAND

9CONNÆCT

This 1040m long bridge across the BatangBaram river at Miri Sarawak in Malaysiacreates a new land link between the new

Miri Port on one side of the river and theCustoms & Immigration Checkpoint to Brunei onthe other.The bridge is located approximatelytwo kilometres upstream of the new port and issome 25km from Miri – a major oil and gascentre.BBR Malaysia’s work included the construction ofthe main river spans – comprising 110m, 180mand 110m cast insitu balanced cantilever singlecell pre-stressed box girders. A total of 82segments – each four metres long – were castusing pairs of formwork travellers. In addition, the1.5m diameter driven steel tube piles, pile capsand pier columns were constructed by BBRMalaysia. Specially designed precast permanentformwork was used to cast the two pile caps forthe main piers in the water. �

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Two islands off the west coast of Norway are in the processof being connected to the mainland by two free

cantilevered (FC) bridges. Hundvåkøy Bridge is a typical FCbridge with a main span of 233m and two side spans of 112 and115m. Storholmen Bridge has two main spans of 160 and 172m.To balance these, counterweight boxes of approximately 45mwere used on each end. Storholmen Bridge has recently beencompleted and construction of Hundvåkøy Bridge has just begun.

HUFTARØY-HUNDVÅKØY BRIDGES, NORWAY

Link to the mainland

TEAM &TECHNOLOGY

� OWNERStatens vegvesen

� CONTRACTORReinertsen Anlegg AS

� DESIGNERStatens vegvesen

� TECHNOLOGYBBR CONA internalBBR CONA rock anchorsTOBE Pot bearings

� BBR NETWORK MEMBERKB Spennteknikk AS (Norway)

BATANG BARAM BRIDGE, MIRI SARAWAK, MALAYSIA

Travelling formwork

10 CONNÆCT

This 11.6km two-lane road, which is part ofthe Tourism Sector Development Project,runs from the Dead Sea Coastal Road –

the lowest point on earth at 427m below sealevel – 7km south of the Hotel DevelopmentArea. It cuts through the mountainous terrainleading to the Maain Spa Road Intersectionwhere magnificent views of the Dead Sea and thenatural scenery can be enjoyed.

BBR Network member Marwan Kurdi &Partners Co. Ltd was engaged to construct thetwo main bridges on the contract – at WadiHammara and Wadi Abu Assal.

The 36m high and 122m long Wadi HammaraBridge has four spans of 30.5m each – and is thehighest bridge in Jordan. It spans the mostdifficult part of the route, between the Maain HotSprings and the Dead Sea. The Wadi Abu Assalbridge has three spans of 30.5m each and is 24mhigh. It has vertical and horizontal curves tocater for the rough terrain and steep slope.

Due to the challenging terrain, the superstructurewas built with pre-cast prestressed T-beams usingBBR CONA internal post-tensioning technologyand the beam installation was carried out using alaunching girder.

Launching in lowestplace on Earth

Dead Sea Parkway Road Project, Jordan

TEAM &TECHNOLOGY

� OWNERMinistry of Tourism & AntiquitiesMinistry of Public Works & Housing

� MAIN CONTRACTORSocieta italiana per condotted’acua spa

� DESIGNERJV Pacific Consultants International &Yamasit Sekkei Inc

� TECHNOLOGYBBR CONA Internal

� BBR NETWORK MEMBERMarwan Kurdi & Partners Co. Ltd(Jordan)

11CONNÆCT

King Abdullah Road is one of Jeddah’s mainavenues, crossing the city from East toWest andintersecting with other main streets. This projectaims to deliver a road free from traffic controlsignals.Already, three phases are either completed orunder construction – and will be followed byfurther phases to allow easy passage across thecity to its west coast.

PHASE 1: INTERSECTION WITH KINGFAHD ROADThis interchange was executed on three levels:� Underpass for King Fahd Road -1km long,

25m wide.� Flyover for King Abdullah Road – double-

deck, 160m long and 30m wide bridge overthree spans of 45, 70 and 45m. Thelongitudinal tendons are BBR CONA internal1906, stressed in two stages while thetransverse tendons were BBRCONA 406.The pier heads were stressed by BBR CONAinternal 1206.

� Two rotary bridges – to recreate the originalintersection at ground level, each 30m longand 17m wide, stressed longitudinally by BBRCONA internal 1906 and 706.

PHASE 2: INTERSECTIONWITH FOUR STREETSKing Abdullah Road will become a1km long, 30m wide underpass,crossed over by four bridges. Thekey components of this phase are:� Khaled IbnWaleed Street Bridge

– a 42m long, 23m wide bridge,stressed by BBR CONA internal1906 longitudinal tendons.

� U-turn Grade Bridge – a 42m long, 7m widebridge, stressed in two stages by BBR CONAinternal 1906 longitudinal tendons.

� Telephone Line Grade Bridge – a 42m long,3m wide bridge, stressed in two stages by BBRCONA internal 1906 longitudinal tendons, willallow the crossing of pedestrians and services(international telephone cables embedded in aconcrete mass).

� Madinah Road Bridge – this bridge willcombine the intersection of Madinah Roadnorth-and-south bounds with King AbdullahRoad. This 30m long and 102m wide bridgewill be stressed by BBR CONA internal 1906and 1206 longitudinal tendons.

PHASE 3: INTERSECTION WITH HAILSTREETThis is another flyover bridge for King AbdullahRoad which involves a double-deck structure, sixspans – five of 40m and one 50m over HailStreet – and executed in three stages:� 2 spans + 5m cantilever (at one end)� 3 spans + 5m cantilever (at other end)� middle span over Hail StreetThe longitudinal tendons are BBR CONA internal1906 stressed in two stages – initial and final. �

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TEAM &TECHNOLOGY

� OWNERMunicipality of Jeddah

� CONTRACTORHuta-Hegerfeld Saudia Ltd

� DESIGNERBBR Systems Ltd

� TECHNOLOGYBBR CONA internal

� BBR NETWORKMEMBERHuta/BBR Prestressing Division(Kingdom of Saudi Arabia)

Founded as a fishing village some 2,500 yearsago, today Jeddah is regarded as thecommercial capital of the Kingdom of SaudiArabia. Jeddah is also the major gateway for

pilgrims to Mecca, the holiest city in the Islamic faith.Currently, major infrastructure investment is underwayto improve and extend facilities for the City’s rapidlygrowing population.

Flying over, under andaround Jeddah

KING ABDULLAH ROAD, JEDDAH, KINGDOM OF SAUDI ARABIA

PHASE 1 PHASE 2 PHASE 3

12 CONNÆCT

Early last September, theProgrammeThree (or Trójka)radio station broadcast news

about the pioneering operationinvolving a bridge slide in Olsztyn.Marcin Ornat, head of BBR PolskaRegional Office in Gliwice and BBRproject manager in Olsztyn, was thereto supervise.“In fact, the whole activity proved to beextremely ‘mediagenic’. We have donesimilar jobs in Poland before, such asour project for the Kutno Bypass, butthis time it was the scale of theundertaking that bred such interest. Fortwo months, the new viaduct was beingassembled just a stone’s throw from therailway line, then – within just four hours– it was moved into position. All thathappening in the city centre of Olsztyn– the operation was really quite ashow!” Marcin Ornat proudly explained.And, after a pause, he added: “ActuallyI think that, compared with other tasksthat BBR Polska faces everyday, it wasan ordinary job, just exceptionally well-executed in the glare of the limelight!”The most labour-intensive job wassecuring the excavation, the earthworks,preparation of the bedding andrestoration of the railway track. Alsothe installation of the shifting equipmentproved to be quite time-consuming – it

took a whole day, but the resultprovided the optimum solution.

FULLY AUTOMATED SYSTEMUsually, shifting sets are used – but notthis time.The one used on this occasion,BBR SL-402, was a fully automatedsystem of jacks, hydraulic pumps andadditional equipment for shifting andlifting. It enables control of a maximumof four shifting (lifting) points and theirrespective loads with a precision of+/- 1mm difference between them.

SPEED & DISTANCESThis system enabled us to move objectswith a speed of approximately 5m/h –and, on the last viaduct, a speed ofaround 10m/h!The following distances were coveredduring the slide:� ViaductWK-3 stage 1 – 28m (the

heaviest element – 2427 tonnes)� ViaductWK-3 stage 2 – 41m� ViaductWK-2 – 42mThe lifting alone took no more thanfour hours, including time for installationof preparatory equipment!The method used in Olsztyn has beenemployed in other countries for anumber of years. Its effectiveness willmost probably make Polish designersreach for it more frequently in thefuture – and will make the investorsappreciate it!

Technology sequence� Casting of the viaduct

superstructure on fixedscaffolding alongside thefinal alignment

� Closing of the railway track

� Construction of theearthwork retainingabutments

� Execution of theearthworks

� Placement of prefabricatedelements to be used forthe slide

� Lifting of the structure,placing of the sliding pads

� Shifting the bridge to thefinal alignment

� Vertical adjustment

� Restoration of theembankment

� Opening of the railway line

Pioneering in Poland

OLSZTYN BRIDGE SLIDE

13CONNÆCT

Incrementallaunching atLas Piedras

VIADUCTO ARROYO DE LAS PIEDRAS, SPAIN

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GESThe Spanish government has allocated a multi-billion Euro

budget for the construction of new rail infrastructure – theirplan is to bring all provincial cities within four hours’ travelling

time from Madrid and six-and-a-half hours from Barcelona.

As part of this major investment, the new Las Piedras Viaduct atAlora – 40kms north of Málaga – will carry the AVE high speedrailway from Córdoba to Málaga. Diana Cobos Roger from BBR

Pretensados y Técnicas Especiales describes the heavy liftingtechniques employed on this major construction project. �

14 CONNÆCT

UP & DOWNLAUNCHINGThe launches were executedfrom both abutments at thesame time – upwards launchingof 592m and downwards of619m.The total weight to be launchedupwards was 7300t whichrequired the use of two pullingjacks BBR S-750 with 31compacted steel strands duringthe last phase of the launching.For the downwards launches,the total weight was 7650t.Two230t retaining jacks – both fixedto the abutment – were neededto secure and hold thestructure. All of the jacks weresynchronized. A retaining forcewas set and, once the pullingforce was bigger than theretaining one, the bridge startedto move.

STRUCTURAL INTEGRITYEach of the 19 piers was passedusing a lifting jack with a strokeof 1000mm and 150t capacity.As the tallest piers were 100mhigh, a security system wasinstalled to ensure thatmovements at the top of thepier did not exceed the onesdefined by the designer.Theangle between the vertical andthe real position of the pier was

The Las Piedras Viaduct is a composite structure which hasbeen built using the incremental launching method. It has atotal length of 1211m, divided into 20 spans – a single span

at 50.5m, 63.5m for 17 spans, then two further spans of 45m and36m – with a slope of 2.4%.

“THE LAUNCHESWERE EXECUTED FROMBOTH ABUTMENTS ATTHE SAMETIME”

TEAM &TECHNOLOGY

� OWNERAdministrador de InfraestructurasFerroviarias (ADIF)

� CONTRACTORALTEC

� DESIGNERIDEAM

� STEEL STRUCTUREMEGUSA

� TECHNOLOGYIncremental Launching, Heavy Lifting

� BBR NETWORK MEMBERBBR Pretensados y TécnicasEspeciales (Spain)

BBR S-750 pulling jacks were used during thelast phase of launching.

In simple terms,“heavy lifting” is a hydraulic lifting techniqueespecially developed for extremely heavy loads. Loadhandling systems often result in considerable savings of timeand costs compared to conventional techniques.This modern

and efficient system can largely substitute traditional lifting,lowering or shifting of heavy elements.

The BBR Network offers complete systems for heavy lifting whichhave been used on many diverse projects around the world. Loadhandling systems require full consideration at an early designstage for structural detailing, construction planning and selectionof the right equipment.

Within the BBR Network, there is extensive experience in thefield of load handling and a complete range of services from theplanning, engineering, equipment supply and execution of anyheavy lifting project can be provided – early involvement of ourspecialists results in a handling scheme that optimises theproject’s economy, efficiency and schedule.

15CONNÆCT

precisely measured, so that if the toleratedvalues were exceeded, the launch process wouldbe stopped automatically.On the top of each pier, a guiding system wasinstalled. Before passing the first pier, a patchloading test was done on site to assess thebehaviour of the structure.The guiding system consisted of two structureswith metallic rollers, positioned on both sides ofthe top of the pier, which helped to guide thestructure whilst allowing for small deviations. Inaddition, the sliding bearings used on the projectincorporated a special design feature whichallowed turns to help correct the launchingalignment.During the last phase of launching, deflectionsand turns at the joint had to be equal at bothends. This task was carried out with the samelifting jacks that were used to pass the piers.Because of the high daytime temperatures, jointwelding between sections had to be doneduring the night, thus avoiding tensionsdeveloping inside the structure as a result ofthermal gradient.

EFFECTING LOAD TRANSFERThe load transfer from the lifting jacks to thepiers was a quite a challenge because, once thelaunch was completed, the viaduct was about75cm higher than the finished level. All groupsof jacks on the piers had to be synchronized andworked in several phases until the viaductreached its correct level.It took around eight months to complete theentire bridge launch. This section of the newAVE route in South Western Spain is expectedto open for passenger services during 2007. �

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“THE LOADTRANSFER FROMTHELIFTING JACKS TOTHE PIERSWASA QUITE A CHALLENGE”

A patch loading test was done to assess the behaviour of the structure.

TECHNICAL INSIGHT

Heavy lifting systems

16 CONNÆCT

A striking array of blending curves and angles, thePeppers Pier Resort was always going tochallenge the construction team. Undaunted,Structural Systems recently completed the designand construction of the post-tensioned slab andload-transfer system that reduced bothconstruction time and building costs.

FLOOR SYSTEMThis landmark project is the largest post-tensioned building project undertaken on theFraser Coast and will be Hervey Bay’s mostexclusive resort facility.With its striking but highly-irregular building shape, one of the keys to asuccessful project was deciding on a floor systemthat was both economical and fast to constructand also providing a solution that will benefit thelong term durability of the structure. Post-tensioned construction was the obvious solution.The project consisted of a post-tensioned beamraft foundation and seven fully post-tensionedsuspended levels, with a total of 42,500m2 ofstressed area. The bonded BBR CONA flatanchorage system, especially designed for post-tensioned slabs, has been used throughout.

COST & STRUCTURALBENEFITSStructural Systems was contractedto design, supply and install thepost-tensioning system for allsuspended and load-transferstructures. Post-tensioning waschosen for both economic andstructural benefits, allowing forreduced beam depths in thetransfer area and thinner slabs,resulting in reduced transfer loads.This reduction in slab thicknessesalso allowed increased floor-to-floor heights achieved in the carpark areas.The deflections of the structurewere minimised to reduceassociated risks with the finishingtrades, thus ensuring long-termmaintenance costs are reducedwhen compared to aconventionally reinforced solution.

Peppers Pier Resort Hervey BayLocated three hours drive north of Brisbane,Peppers Pier Resort Hervey Bay is set tobecome one of Queensland’s premier beach-side destinations. In keeping with its seasidevillage lifestyle environment, the resort’sdistinctive curvature and tiered design isinfluenced by the form of ocean waves.It features a landscaped lagoon swimmingpool, fine dining restaurant, premium confer-ence and meeting facilities and a health club.Hervey Bay is one of Australia’s mostpopular holiday escapes offering a warmclimate, beautiful beaches and a host of landand water-based activities. It is also the bestwhale-watching destination in Australia.

PEPPERS PIER RESORT, HERVEY BAY, QUEENSLAND,AUSTRALIA

Beautiful challenge down under!

The construction of 42,500m2 of post-tensioned slabs at the Peppers Pier ResortHervey Bay – a landmark project in Queensland – is described by Justin Hampton ofBBR Network member Structural Systems as a “beautiful challenge” to its builders.

17CONNÆCT

The MTC site started in October 2005 and is growing into a14,000m2 multifunctional shopping centre, with 9,000m2 of retailspace and 150 covered parking places on the roof. Situated in

TheWhite City Shopping Development inWest London willbe one of Europe’s largest when it opens in 2008 and BBRNetwork member Structural Systems (UK) Ltd is on the

case.The £700m project is due to create 5000 jobs with an area of120,000m2 comprising retail and commercial space, cinemas andpublic areas. At the start of the project, the site was divided byLondon Underground’s Central Line. A concrete overbuild “tunnel”now hides the railway and work can at last start on thesuperstructures to the east and centre of the site. Meanwhile to thewest, construction is 80% complete.

TWO-WAY POST-TENSIONINGStructural Systems (UK) Ltd has been responsible for the slab post-tensioning work to the level 20 and 30 flat slabs, plus some of themore complex beam areas of level 40.The majority of the level 20and 30 slabs are on 8x8m grids.The 225mm deep slabs have beentwo-way post-tensioned using the BBR CONA flat 505 bonded PTsystem.

Cakovec, north Croatia, it was the second project completed withpost-tensioned slabs and executed by BBR CONEX of Croatia.The design of post-tensioned slabs was undertaken in collaborationwith Dreibau Ingenieurs Conseils, Switzerland. Originally, the projectwas conceived as a reinforced concrete three storey framedstructure with ribbed slabs made of precast TT girders.The buildingis around 97x78m with a column grid of 16x10m.

REDUCING TIME & MATERIALSThe original structural solution for the building – ribbed precastgirders and beams – was redesigned and replaced with a higher specsolution, based on post-tensioned flat slabs with shallow beams forthe larger 16m span. Construction time was cut in half andformwork expenses were reduced by 75%. In addition, the newstructure is lighter, with a lower centre of gravity and better seismicproperties. Also, floor-to-floor heights were increased by up to 42cm.The floor structure for this project was so advanced that it had tobe tested to prove that it could cope with the demands. So, sheartesting of critical columns was performed.Testing was carried outaccording to American Code ACI-318/2002. The slab behaved in afully elastic manner, with residual elastic deformations of less than 1%.

DEMANDING CANTILEVERThe most demanding part of the structure was a 5.5m widecantilever section of the slab on the edge of the building – 43m long.On the second slab, there are 18 parking places. It was designed as awaffle slab without additional beams, in order to control the long-term deflections by reducing the self-weight. Again, post-tensionedslabs proved to be a very competitive alternative for any kind ofstructure, in terms of economy, time and performance.

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MTC MULTIFUNCTIONAL SHOPPING CENTRE,CAKOVEC, CROATIA

Competitivealternative design

WHITE CITY SHOPPING DEVELOPMENT, LONDON

Europe’s largest retail centreMASSIVE SLAB AREASReinforcement is very light, being confined to edge or constructionjoint reinforcement, top mats at columns and punching shear links atsome columns.The slab areas are massive – level 30 alone is 150x200min total.The total PT slab area is expected to reach 80,000m2.Whereas the lower levels support car parking, level 40 carries retailloading, mall loading – including maintenance vehicles – and even fireengine loads. Also, a number of the stanchions from the three-storeysteel superstructure do not land on grid.The solution is a series ofbeams including transfers as required.Through the central part of thesite, where grids are most erratic, the beam size has been minimisedby employing post-tensioning.To date, the largest beam has been a24m spanning beam – 3000x1800mm deep – and containing sevenCONA internal 1906 multi-strand tendons.Future work includes the five-storey anchor store in the featurecorner of the site and more post-tensioned flat slabs across the newlyaccessible central area. �

18 CONNÆCT

absence of joints means a smooth, aestheticallyappealing appearance, a high resistance to appliedloading, easy care and long-term durability.

SLAB CONSTRUCTIONThe 35,000m2, 165mm thick slab was poured in12 stages, with slabs ranging in size from 2300 to3345m2. Each slab has crossed-over tendons tothe adjacent one, which means only a single openjoint within each area. The post-tensioned floorslab was designed by BBR Contech utilising a BBRCONA flat 405 tendon configuration.Allied Concrete’s new full delivery concreteflooring division, Conslab Ltd, was responsible forconstructing the slab and BBR Contech was againengaged as the specialist post-tensioningcontractor. This was a continuation of the sameteamwork which has delivered a large number of

This massive system forms thefoundation for a storehouse that isnearly 4.5 hectares in area –stretching for almost half akilometre alongside the railway linein Hamilton’s Crawford Street, inNew Zealand.

STRINGENT REQUIREMENTSThe rail store is designed to houseFonterra’s milk powder exportsbetween their point of origin – thecentral North Island – and the railnetwork to their port of departure.Comprising three separate areasand a covered rail siding, it imposedstringent requirements for a high-performing and effective flooringsystem – admirably met by post-tensioned floor slabs, whose total

high performance concrete floors for many clientsover recent years.“The sheer size of the building requiredmeticulous planning, right from the start – thiswas bigger than anything any of us had ever donebefore!” said Kim Barrett of Haydn & Rollett, thecontractor for the project.

REHIRED FOR APRON SLABFollowing on from the successful completion ofthe main storehouse slab, BBR Contech wasapproached to configure a heavy duty post-tensioned apron slab which runs between themain storehouse and the adjacent rail siding. This15,000m2 apron slab is required to deal withclosely spaced and fully laden containers, stackedtwo high. In addition, the slab must also resistloads from large container handling equipmentwith peak axle loads approaching 100t.

SHARING KNOWLEDGEBBR Contech worked closely with Australian BBRNetwork member, Structural Systems Ltd, toconfigure a slab which would meet all ofFonterra’s design criteria. The result was a slabmeasuring some 500m long and 30m wide,constructed in six separate pours. The slab depthis 270mm with perimeter edge thickenings of380mm. The post-tensioning comprises BBRCONA flat tendons. Structural Systems Ltd hasdesigned similar apron slabs in Australia and this isthe first such heavy duty application for NewZealand.The close collaboration between BBRNetwork members demonstrates how specialisedtechnical know-how, consulting expertise andlocal experience can deliver certainty ofperformance for some very challengingengineering projects.

TEAM &TECHNOLOGY

� OWNERFonterra Cooperative Group

� CONTRACTORHaydn & Rollett Construction Ltd

� DESIGNERBBR Contech (New Zealand) /Structural Systems Ltd(Australia)

� TECHNOLOGYBBR CONA flat

� BBR NETWORK MEMBERBBR Contech (New Zealand)

STOREHOUSE FLOOR IN NEW ZEALAND

Massive milk powder store

As far as post-tensioned floor slabs go, the Fonterra Co-operative Group project thatBBR Contech recently completed for Haydn & Rollett and Allied Concrete must surely

rate as one of the largest, according to BBR Contech’s Keith Snow and Jeff Marchant.

Facts & FiguresTotal area of post-tensioned slab on ground 50,000m2

Tendons 60,000mStrand 300tConcrete Approx. 10,000m3

19CONNÆCT

A lready one of the most successfulcentres in Austria, the EuroparkShopping Centre on the outskirts of

Salzburg, underwent a major expansion which hasextended the retail sales area from 30,500m2 to50,000m2. Dipl. Eng. Michael Schreiner ofAustrian BBR Network member, VORSPANN-TECHNIK GmbH & Co. KG, reports on howthe use of internal unbonded prestressing – tocontrol the static behaviour of the flat slab –delivered an excellent solution for the client andsaved valuable construction time.

POST-TENSIONING SYSTEMThe selected prestressing system was the BBRCONA CMM 406 with bands as tensile elements.

A key element of this system is thecombination of four strands, with anominal cross-sectional area of150mm2, arranged in a band. TheVT-CMM band offers theadvantage, in comparison to amonostrand, of easier and fasterplacing of tendons on site. Inaddition, tendon cutting andmounting and prelocking of thefixed anchorages can also becarried out off-site, in the factory.The in-situ concrete slab had athickness of 45cm to 60cm and aspan of 16m by 8m.The tendonswere placed near the columns, in

the direction of the principal axis.A slab thickness of 45cm permits application ofthe “free tendon layout” method.This methodrequires tendons to be fixed only at the upperand lower reinforcement layer – therefore, specialspacers for tendons are not required.

PRESTRESSING WORKSThe three post-tensioned slabs had an averagearea of 16,000m2 and had been divided in 10 to15 construction stages. In total, 2615 tendons(400t) with an average length of 32.65m wereproduced, installed and stressed in 11 months.This project was an excellent demonstration ofthe benefits of the BBR CONA CMM technologyand the client certainly appreciated the expertiseof the highly professional and dedicated teamfrom the BBR Network. �

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� OWNEREuropark Errichtungsgesellschaft mbH

� MAIN CONTRACTORJoint venture between Strabag AG,Alpine Mayreder Bau GmbH, DywidagGmbH

� DESIGNERZiviltechnikergesellschaft HerbrichConsult, Salzburg

� TECHNOLOGYBBR CONA

� BBR NETWORK MEMBERVORSPANN-TECHNIK GmbH & Co. KG(Austria)

SALZBURG SHOPPING CENTRE EXPANSION

SPEEDYSOLUTION

20 CONNÆCT

Zelimir Bodiroga and Damir Pavicic fromBBR CONEX of Croatia report on theirthird project completed with post-

tensioned slabs – in the historic town and growingski resort of Kamnik on the banks of the BistricaRiver.The building is known as “Metuljcek” – Slovenianfor “little butterfly” – and is a very demanding andcomplicated project which started in March 2006.It comprises two underground parking levels, twocommercial and three residential floors, it has atotal area of almost 30,000m2.We undertookdesign of the post-tensioned slabs in collaborationwith Dreibau Ingenieurs Conseils, Switzerland.

ORIGINAL PLANSThe original concept for the building was aneight storey framed structure with an irregularfoot-print. It consisted of two triangular sectionswhich, together, formed an irregular butterflyshape.The vertical bearing structure comprisedtwo triangular cores, with verticalcommunications, columns spaced at 6 or 7m andretaining walls in the underground structure.Floor construction was of reinforced concretecast in situ slabs, supported by beams betweencolumns.There was also a circular ramp in onecorner of the building for car access to the under-ground parking levels. Numerous holes and shaftsfor installation and air circulation had to be incor-porated in the slabs.Together with the irregularshape of every part of building, the design wasway too complicated – from every aspect!

REDESIGN ENHANCESBBR CONEX was involved in redesigning the“little butterfly” much more than is usual on aconstruction project. Floor slabs were redesignedas completely flat and all the beams wereremoved – thickness of the slabs ranged from18cm to 22cm.The basement slab is also post-tensioned, with the thickness reduced from 70cmto 45cm – and no water isolation was needed asa post-tensioned basement slab is already water-proof. In the superstructure, columns ofcomplicated cross-section were replaced with RCwalls, arranged radially around the cores.This waythe construction was simpler, faster – and, moreimportantly, enabled flying form tables to be used.Economy of the structure was greatly enhanced,whilst stability and seismic properties were alsoimproved. In addition, with new walls instead ofthe columns, the problem of punching shear wassolved and great deal of rebar was spared.

POST-TENSIONINGThe slabs and basement slab werepost-tensioned using 0.6", greasedand PE-coated, 7-wire BBR CONASingle T15SUPER unbondedmonostrand tendons with BBRCONA Mono anchors.Tendoncross-sections are 150mm2, with atensile capacity of 279kN.Tendonsin the elevated slabs had no

intermediate anchors, as the slabs were poured incontinuously for each “wing” – the average areaof one pour was just under 1600m2 and requiredabout 300m3 of concrete.In the basement slab, tendons were parabolic andhad one or no intermediate anchors. Tendonlayouts were complicated, often with threefamilies of tendons – in three different directions– interweaving with each other.The total area of post-tensioned slabs is about27,000m2 – including seven elevated slabs and thebasement slab. Every floor slab is divided intotwo parts, each cast in one pour.The basement slab was cast in eight pours.Tendons had to be stressed from above or frominside of the slab, as there was no space for

MULTIFUNCTIONAL RESIDENTIAL BUILDING, SLOVENIA

Building the little butterflyTEAM &TECHNOLOGY

� OWNERCM Celje

� CONTRACTORCM Celje

� DESIGNERCM Celje with DreibauIngenieurs Conseils (Switzerland)

� TECHNOLOGYBBR CONA unbonded

� BBR NETWORK MEMBERBBR CONEX (Croatia)

stressing between the edge of the slab and thetrench walls – about 1m is usually enough foredge stressing. Demanding and complicatedlogistics were involved in the project, mainly forthe basement slab, as the design was complicatedand the site had very little space around thetrench.This project is a perfect example of the variety ofenhancements that the post-tensioning of slabscan yield.

21CONNÆCT

Warwick Ironmonger, General Manager – Middle East Region for Nasa(BBR) Structural Systems LLC reports on how post-tensioned slab sol-utions are delivering a range of benefits for their customer in the UAE.Building upon its significant track record in the Middle East, BBRStructural Systems (BBR-SSL) has recently completed the design andconstruct post-tensioning works associated with a prestigiousresidential development in Al Nuaimiah for His Highness SheikhHumaid bin Rashid Al Nuaimi, the Ruler of the Emirate of Ajman.

ECONOMICAL SOLUTIONThe complex consisted of 15 apartment buildings, each comprising of17 suspended flat plate, post-tensioned slabs with a combined totalfloor area of 180,000m2. Post-tensioned floors were adopted topermit an economical solution – satisfying the project requirement ofthin slabs and minimal use of false ceilings, whilst achieving the earliestpossible completion date. The slabs were typically 230mm thick forspans of up to 8500mm and increased locally to 250mm in thevicinity of 10,800mm spans.

MINIMAL FORMWORKThe complex was the first of its type in Ajman and the completion ofthe suspended floors at a rate of three levels per building per month– using only one set of formwork, made possible through the post-tensioned solution – facilitated the earliest onset of foreigninvestment in the Emirate of Ajman and offered neighbouringresidents of Dubai and Sharjah the earliest opportunity to re-locateto more affordable accommodation in the Emirate of Ajman.

FURTHER CONTRACTSFollowing the success of this project, a second complex of 16residential buildings has been proposed in nearby Al Khor and, despitethe fact that contracts have been let to four main contractors, BBR-SSL has managed to secure the post-tensioning works associated withall of these buildings. Post-tensioning site works are currently inprogress for 12 of the 16 new buildings.

For their first slab task, BBR Polska was lucky to have theadvantage of extensive shared know-how from BBRContech NZ – the slab post-tensioning giant. That was in

2005 and, with this special technology becoming more-and-morepopular in Poland, since then BBR Polska has participated in severalprojects.A special industrial slab on grade has been designed for Alpex, a fruitprocessing company located in Leczeszyce near Grojec. It wasdestined for the apple juice concentrate warehouse and needed tocarry 60 containers, about 14m high, each weighing over 200t.“This meant that a load of 200kN on each of the 12 feet of thecontainers had to be taken into account in the design.” explainedproject manager Anna Plusko, “Consequently, the slab on graderequired a substantial thickness – from 24 to 35cm – which requiredover 400m3 of concrete!”The 1317.75m2 slab needed no expansion joints because it was post-tensioned using PE coated unbonded cables.Through its continuous expansion programme, helped along by BBRPolska, the Alpex plant is now able to produce 24,000t ofconcentrated fruit juices – 95% of its products are exported to theEU, USA and Japan. �

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Prestigious residentialdevelopment

FRUIT JUICEWAREHOUSE FLOOR,POLAND

Taking the load

22 CONNÆCT

A paper on design andconstruction aspects of post-tensioned LNG storage tanks inEurope and Australasia has beenproduced by BBR’s Hudson Lun,Frank Filippone and DianaCobos Roger, with contributionsfrom members of the BBRNetwork, a summary of the keyaspects is reproduced here.

NEED FOR STORAGETANKSThere are significant natural gasreserves globally and explorationcompanies are rapidlydeveloping facilities for exportingthe natural gas, with thecorresponding receiving facilitiesbeing planned and built inemerging markets. With atimeframe of some 5-10 years

for planning and construction,there is currently much activityunderway in the LNG supplychain in preparation for currentand predicted demands.The growth in this sector hasseen the development ofsignificant LNG storage tankfacilities for LNG exporters andimporters. These massivestorage tanks are essential for

reception and safe storage ofthe liquid gas.

STORAGE CONDITIONSThe storage temperature ofLNG is -162°C and is describedas “cryogenic” conditions. Theliquid occupies 600 times lessspace than natural gas in itsgaseous state, making it practicalto ship by ocean tanker. Inaddition, it is stable and safe

TECHNOLOGY MEETS DEMANDFOR STORAGE

Over the past few decades, world consumption of LNG – Liquefied Natural Gas –has increased more than five-fold and it is predicted that growth will continue tobe very strong.The rising demand from large markets such as China and India,

combined with the increasing popularity in a large number of other smaller markets hasresulted in the development of many new LNG facilities throughout the world.

World LNGconsumption soars

23CONNÆCT

because, even though compressed in volume, theliquid remains at normal atmospheric pressure.On land, LNG is stored in specially engineeredand constructed double-walled storage tanks. Atthese temperatures, the requirements for thecontainment structures are very stringent andpost-tensioned concrete tanks are ideally suitedto the task.The large concrete tank structures are extremelyrobust with significant amounts of prestressingrequired – all being designed and installed undertightly controlled quality conditions, withhardware requiring special certifications.

DESIGN AND CONSTRUCTIONDesign and construction techniques have beenspecially formulated for LNG tank construction.The outer walls of the tank are most commonlyconstructed from post-tensioned concrete.Thevoid between the tank double walls is filled withinsulation.Tanks are around 80-90m in diameter and 50mhigh, with a wall thickness of some 750mm.The post-tensioning tendons are very large andtypically run both vertically and horizontally.� Vertical tendons

These can either be single directional tendonsfrom the top of the tank, terminating in arecess or socket at the bottom – or “U”tendons starting at the top, coming verticallydown through the tank, curving aroundthrough 180° degrees and returning to the top.

� Horizontal tendonsTypically, these start at a buttress and travelhalf way around the tank, terminating at theopposite buttress. Another tendoncommences from the same buttress andtravels back through the remaining half of thetank, terminating at the original buttress – thuscreating a complete “hoop” with the twotendons.For efficient use of post-tensioning, adjacenttendons are anchored at alternate buttresses,90° from the actual buttress.

LNG tanks are generally constructed underdesign and build arrangements, with the principalcontractor being responsible for determining thespecific design requirements for the prestressedconcrete.The post-tensioning specialist examinesthe required force profile and details the spacingand tendon size for the post-tensioning.

PT DESIGN REGULATIONSThere is no official standard for the design ofthese tanks and the first guidelines publishedwere based on pioneering work in cryogenicapplications. According to fip SR 88/2, testing isrequired to be carried out on:� Prestressing steel – at room temperature and

at cryogenic temperature� Tendon anchorage assembly – at room

temperature and cryogenic temperature� Load transfer – at cryogenic temperature

Tests according to these guidelineswere completed for the BBRTechnology. Subsequently, a newguideline has been published tocover prestressing in cryogenicapplications – ETAG 013.The testing and quality control ofprestressing materials used incryogenic applications is critical tothe successful performance of thecontainment systems.The BBR CONA post-tensioningsystem is in full compliance withthe testing regime under cryogenicconditions.

EXPERIENCE & EXPERTISELNG storage tanks are ideallysuited to construction methods

employing slipformed or climbing insituconcrete construction combined with post-tensioning. The design and installationtechniques are very specialised and requirespecially certified and tested materials andhighly experienced contractors.A large database of information has beendeveloped during construction of these massiveconcrete structures and many innovativetechniques have streamlined activities associatedwith the supply and installation of post-tensioning materials and other construction-related engineering.The nature of the typicaldesign and build project delivery method hasseen the formation of some strong design andconstruction relationships and this has seen therapid development and optimisation of designand installation techniques. �

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Technological advances and increased competition, thus loweredcosts for handling, have made LNG more attractive to USenergy suppliers over recent years. Record high receipts of

LNG were reported in 2003 – the highest since 1979.Existing plants are planning expansion which will provide a totaladditional peak time capacity of 2.440 billion cubic feet per day.Meanwhile, over 20 new import facilities are being evaluated by theauthorities and many more are at the planning stage. These new plantsinclude eight offshore and 19 onshore installations which togetherwould bring an additional peak time capacity of approaching 31,500million cubic feet per day.Until now, the highest capacity of LNG storage has been close tocentres of population in the Eastern United States. By far and away,the majority of current projects, either at the early stages or inconstruction, are located in the Gulf of Mexico region and, alone, areset to increase US LNG capacity by 55%.Generally, the demand for domestic LNG is expected to increase ascompanies make inroads into several niche markets such as vehicularfuel and as a replacement for propane at facilities off the pipeline grid.

24 CONNÆCT

When completed, thesestorage tanks will form anintegral part of a newreception terminal to handleLNG into the energy grid,through the port of PembrokeDock near Milford Haven inSouth Wales – and this iscurrently the largest civilengineering package beingundertaken anywhere in UK.The total project is beingmanaged by Chicago Bridge &Iron (CB&I), on behalf of theQatar Petroluem and ExxonMobil companies. Other worksinvolved in the project includethe supply of transport vessels,reinstatement of existingunloading pier, pipeinfrastructure, re-gasification

plant and the five concretetanks and associated holdingtanks.When complete, each ofthe post-tensioned concrete

tanks will be 35m high andhave a 92m diameter, giving acircumference of approximately290m.

BBR PT FORPERFORMANCEPost-tensioned strand for theproject is installed and stressedboth vertically and horizontally.Vertically, the strand will bestressed through a U-shapedtendon from the ring beam tothe base. Horizontally, post-tensioning will be appliedthrough a pre-formed buttresslocated at the quadrant points ofthe tank.The buttress arrangement allowsfor the hoop tendons, whichmake up the circumference ofthe tank, to be stressed in twohalves to improve stressingforces and minimise frictionlosses. Four buttresses areformed to allow alternatingtendons to be stressed at 90° toeach other, to ensure the loadsare uniformly distributed aroundthe tank and reduce both thestressing loading on eachbuttress and construction issueswith the anchor installations.Post-tensioning was favouredover traditional reinforcement asa result of the cryogenictemperatures needed to keepthe gas in a liquid form and thesuperior ductile characteristics ofthe high tensile steel strands atlow temperatures. In addition,the cylindrical concrete tankswere slip-formed to the underside of the ring beam to speedup the construction programme.

UK’s largest civils package

SOUTH HOOK LNGTANKS, PEMBROKE DOCK,WALES

This massive infrastructure project is being undertaken by BBR Network memberStructural Systems UK Limited, in conjunction with the main contractor Taylor

Woodrow Construction and involves the construction of the five 92m diameter post-tensioned tanks to provide the outer shell of holding tanks for Liquid Natural Gas (LNG).

TEAM &TECHNOLOGY

� OWNERQatar Petroleum & ExxonMobil

� CONTRACTORTaylor WoodrowConstruction Ltd

� DESIGNERChicago Bridge & Iron

� TECHNOLOGYBBR CONA internalcryogenic

� BBR NETWORKMEMBERStructural Systems (UK) Ltd

Project StatisticsHorizontal cables = 670 – 19 x ø15.7 strands+ High tensile steel strand ø15.7

Horizontal cables = approx 156m long each+ Galvanized ducting = 105km

Vertical cables = 420 – 12 x ø15.7 Strands+ High tensile steel strand ø15.7

Vertical cables = approx 70m long each (‘U' tendons)+ Galvanized ducting = 29km

Strand wedges = 38,000Multi strand anchors = 2,180

Cement for duct void filling = 1,000t

STRAND INSERTIONOnce the tank walls haveattained the required designstrength, the high tensile steelstrand to be post-tensioned isfed through the pre-laid ducting.Ducting, within the slipformedtank walls, consists of a series ofvertical and horizontal galvanizedtubing installed at approximately300mm centres.

MULTI-STRAND JACKINGFollowing the placement of thestrand which will provide thehoop stressing forces to theconcrete tank, stressing isundertaken using a specialist“multi-strand” jacking operation,

thus increasing the tensilecapacity of the concrete and en-suring the tank is robust enoughto withstand the pressure should

the inner tank leak.To completethe operation, the ducts whichnow contain the stressed strandare filled with cement grout, to

both fill the remaining voids andbond the high tensile steelstrand into the ducting.The construction on the projectis estimated to run fromSeptember 2006 to July 2008and is being programmed sothat three of the five tanks willbe online to handle the firstdelivery of LNG through theport in February 2008.To meetthe projected completion dates,operations will require StructuralSystems UK to operate twoconstruction crews fromFebruary 2007 to December2007 to satisfy the client’srequirements. �

25CONNÆCT

The nature and form of construction ofthese large concrete tanks can readily beadapted to the storage of other

materials. Another significant facility designed andconstructed by Chicago Bridge & Iron (CB&I) hasrecently commenced in the United ArabEmirates. Warwick Ironmonger, General Manager– Middle East Region for NASA (BBR) StructuralSystems LLC, describes their project for GASCO.In this scheme, four full containment LPG tanksfor storing propane and butane are beingconstructed in Ruwais, to the west of Abu Dubaicity. Each 34m high tank is 62.8m in internaldiameter and has a domed concrete roof.These tanks generally have 500mm thick wallswith a lower taper to 800mm thick at the base

and are horizontally post-tensionedonly, with vertical actions normallyreinforced. The outside face of theconcrete wall here is static formedwith the inner face cast against apermanent steel liner.NASA (BBR) Structural Systems’task consists of the design and de-tailing input, supply, installation siteservices including the stressing andgrouting of around 820MT of PCstrand within the walls of the tanks.Horizontal tendons typicallycomprise 19 x 15.7mm diameter,1860MPa UTS strands housed,stressed and grouted within

galvanised ducting of 105mm ID have beendetailed to satisfy the effective force profilespecified by our client. Each tendon isapproximately 105m length and is to be stressedfrom both ends. The cryogenic version of theBBR CONA internal multi-strand anchorages,positioned at the buttresses, were chosen toanchor these tendons as it was specified that thepre-stressing system should be workable at low(cryogenic) temperatures.Construction of the walls, which are being cast in3.4m lifts, commenced in July 2006 – with theanchorage castings and ducting already cast intothe concrete of the first two lifts – and isexpected to be completed in mid-2007.

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Adaptable techniqueTEAM &TECHNOLOGY

� OWNERGASCO

� CONTRACTORSnamprogetti (Main) /Chicago Bridge & Iron (Tank)

� ENGINEERSnamprogetti / Bechtel

� TECHNOLOGYBBR CONA internal cryogenic

� BBR NETWORK MEMBERNASA (BBR) Structural Systems LLC(UAE)

26 CONNÆCT

TheAdriatic LNGTerminal,which will be operational inApril 2008, is beingconstructed in a large dry-dock facility in Algeçiras insouthern Spain. This samedry dock was previouslyused to build the fib award-winning BBR post-tensionedconcrete structure for theMonaco FloatingBreakwater. Two BBRNetwork members – BBRPTE and KB Spennteknikk AS –are both heavily involved.

The Adriatic terminal is arectangular structure, 180m long,88m wide and 47m high, withthe capability to hold two125,000m3 LNG tanks. It is agravity-based structure, whichwill be towed to its finaldestination, 17km off the coastof Italy, where it will be used forreceiving, storage andregasification of LNG.Approximately 90,000m3 ofconcrete, 30,000t of rebar andpost-tensioning steel and350,000t of solid ballast arebeing used for the constructionof the terminal.BBR PTE is developing the post-tensioning works in associationwith two other companies.Thisproject includes both horizontaland vertical post-tensioningutilising tendon configurations of12 and 19 15.2mm strands.

FloatingTERMINAL

ADRIATIC LNGTERMINAL,SPAIN-ITALY

FROM BARCELONATO CARTAGNA,SPAIN The construction of the fifth

and sixth LNG tanks inBarcelona, for the project

owner, ENAGAS, started in 2003.The two tanks have an innerdiameter of approximately 80mand an inner height of 37m – thetotal overall height of the structureis 49.5m. The outer containmentwalls are 800mm thick, post-tensioned vertically and horizontallywith the cryogenically proven andtested BBR CONA post-tensioningsystem.An approximate total of 600t ofprestressing steel was required foreach tank.There were 140horizontal tendons, each containing15 15.2mm strands. The 140 vertical

tendons were of a loop configuration containing19 15.2mm strands. In addition, there were 12horizontal tendons in the external ring of thefoundation slab each with 24 15.2mm strands.To ensure corrosion protection of the tendons,grouting was carried out using a speciallydeveloped vacuum grouting technique withspecial high-turbulence mixers. All post-tensioningwork on these tanks was conducted by BBRNetwork member, BBR PTE (Spain). The fifthtank was finished in 2004 and the post-tensioningwork on the 6th tank was completed in late 2006.Another 150,000m3 LNG tank is beingconstructed by BBR PTE (Spain) – in Cartagena –with an outside diameter of 81m and an innerheight of 40m.The containment walls are 800mmthick, post-tensioned vertically and horizontallywith BBR CONA. Construction is expected to becompleted in summer 2007.

LNG marketgrows in Spain

Left: 53 custom-madeTOBE potbearings are being used as supportfor four steel topside modules on theGBS concrete top slab.The bearingsare designed to withstand blastevents and uplift during safeshutdown in case of earthquakes.

27CONNÆCT

Dipl.-Ing.(FH) ThomasWeber ofVORSPANN-TECHNIK GmbHdescribes his company’s successin proposing and using BBRVTCONA CMM unbondedprestressing in the design ofdigestion tanks for the GutGrosslappenWastewaterTreatment Plant in Munich.

WINNING WAYSVORSPANN-TECHNIK won thetender for the execution of theprestressing works thanks to theuse of the BBRVT CONA CMMbands.The advantages of theprestressing concept comparedto the original design were thedetermining factors for thisdecision.The wastewater treatment plantMünchen I – Gut Grosslappencurrently possesses a digestiontank system with six digestiontanks.These tanks were built insections – in 1961, 1968 and1972. Each tank has a volume of6500m3, giving an overallvolume of about 39,000m3. Fordiverse technical, safety-relatedand economic reasons,construction of new tanks wasinevitable.The StadtentwässerungswerkeMünchen (SEW) thereforedecided, in 1998, to build fournew digestion tanks – each nowoffering a volumetric capacity of14,600m3.The construction ofthese tanks and the operationsbuilding was put out to tenderat the end of 2002.

ORIGINAL DESIGNThe original design envisaged across-section in the form of adouble cone cylinder. In this plan,the occurring vertical forceswere transferred mainly via thebottom plate of the passage, aswell as the lower cone point ofthe tank.The prestressing concept linkedto this load-bearing performanceenvisaged a horizontal annularprestressing with individualunbonded monostrands, eachinstalled around 360°. Theplanned anchorage recesses ofthe prestressing tendons werearranged at 90° intervals around

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Some 30 years ago, BBR supplied and installed its thenpioneering HiAm anchored strands for the Olympia Stadium

project, the former home of Bayern Munich Football Club. Now,next to the team’s new home at the Allianz Arena, engineers fromBBR Network member VORSPANN-TECHNIK GmbH working onthe Gut GrosslappenWastewater Treatment Plant have againcreated an innovative new solution.

GUT GROSSLAPPENWASTEWATERTREATMENT PLANT, MUNICH, GERMANY

Innovation continuesin Munich

Overview of new digestion tank system – front left, digestion tank (DT1) with installed conic prestressing tendons,

behind DT2 with inner funnel formwork before concreting, DT3 with rising inner formwork and, rear right, DT4

with circumferential funnel formwork.

�

28 CONNÆCT

the top of the tank, in order toachieve the highest possibleforce distribution.For the meridian prestressingtendons (vertical prestressingtendons) seven to 22-strandpost-tensioned prestressingtendons were planned. Thelarge 22-strand prestressingtendons ran through the lowercone point, intersecting up tothree layers.The loweranchorage of all post-tensionedprestressing tendons wasrealised by means of a so-called“loop” anchorage.

IMPROVED PROPOSITIONWITH BBR SYSTEMThe detailed proposal wasworked out by the civilengineering company Peter JägerBauingenieure AG of Basel andexclusively uses BBRVT CONACMM 0406 150 1770 unbondedtendons, with the proviso that

no modification be made to theexternal geometry of the tanks.The prestressing concept offereda cross-section optimisation, witha better transfer of the verticalforces to the foundation. Incontrast to the original design,these forces are almostexclusively transferred, via afoundation ring at the equator,

to bored piles into the ground.Compared to the tender design,this results in lower dimensionsof the foundation area and inlower construction costs.With this detailed proposal, theARGE Neubau FaulbehälterKlärwerk Grosslappenconsortium, consisting ofWayss

& Freytag Ingenieurbau AG andBauer Spezialtiefbau GmbH, wonthe tender based on bothtechnical and commercial criteriaand was commissioned to buildthe four digestion tanks and theoperations building in spring2003. A few months later,VORSPANN-TECHNIK GmbHreceived the order fromWayss

& Freytag to carry out all theprestressing work for thedigestion tanks.

PRESTRESSING INPRACTICEFor the prestressing, BBRVTCONA CMM unbondedtendons were used exclusivelythroughout. Depending on theirposition, three different types oftendon profiles were adopted.Conic prestressing tendonsThe conic prestressing tendonswere installed in four assemblies,consisting of 51 tendons each –220 per tank – in the lowercone. These tendons “hang up”the lower cone on thefoundation ring.The stressing ofthe tendons was carried out inthe construction joint betweenconstruction stages two andthree (equator area), with the

tendons being stressed on bothsides synchronously for a betterforce introduction and dis-tribution of the elongation value.Ring tendonsThe ring tendons were arrangedover the complete height of thetank, standing upright. In total,227 tendons per tank wereinstalled. As in the originaldesign, they were installedaround 360° and were alsostressed in anchorage recessesstaggered by 90°. In areas withhigh load concentration –particularly around the equator– it was necessary to increasethe prestressing force from thering tendons. In view of thelimited space available, fourtendons were arranged oneafter another. Ring tendoninstallation was carried out witha dispenser especially developedby VT for this project.Meridian tendons (verticaltendons)The meridian tendons weredivided in two length groups.The shorter tendons wereanchored and stressed inconstruction stage 5, the longertendons in construction stage 8.The 96 meridian tendons wereanchored in the lower cone bymeans of a loop.The loops werearranged in 24 groups, eachcontaining four tendons.

TEAM &TECHNOLOGY

� BUILDING OWNERStadtentwässerungswerkeMünchen (SEW)

� CONTRACTORWayss & FreytagIngenieurbau AG

� DESIGNERPeter Jäger Bauingenieure AG

� TECHNOLOGYBBR CONA unbonded

� BBR NETWORKMEMBERVORSPANN-TECHNIK GmbH,Munich

“THE PRESTRESSING CONCEPT OFFERED A CROSS-SECTION OPTIMISATION,WITH A BETTERTRANSFER OFTHEVERTICAL FORCES TOTHEFOUNDATION”

View of digestion tank 1 – construction stage 5 completed, digestion tank 2 – construction stage 5 completed, inner

framework construction stage 9 completed, and part view of digestion tank 3 – construction stage 8 completed.

Tensioning of the conic prestressing tendons withVT 1000 prestressing jacks.

29CONNÆCT

This new cement silo will have the ability to loadthree tanker trucks within its perimeter at onetime.This innovation means that separate loadingplant is not required – making for a more efficientand quicker turn-around of the ever-busy tankers.Construction of the ring pile cap commenced on1 April 2006 with the project having a completiondate of 22 December 2006.This required theutilisation of a quick and reliable formworksystem. BBR Network member Structural SystemsLimited successfully bid for the project, based onusing its own in-house slipform system. Coupledwith the BBR CONA post-tensioning system, thispresented the client with a packaged solution fora difficult project with a tight constructionprogramme. �

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MELBOURNE CEMENT FACILITY

State-ofthe-art silo

Project facts & figures� Capacity – 35,000t� Height – 57m� Diameter – 30m� Wall thickness – 900mm reducing to 450mm� Reinforcement – 535t� Post-tensioning – 130t� Concrete – 2860m3

SPECIAL LICENCEWhen the construction workstarted, the prestressing system– with licence number Z-13.1-71 – had been technicallyapproved by the buildingauthorities. But since, for thisproject, tensioning wires with aslightly higher yield stress wereused and the minimumdeflection radius of 2.6m forthe loop anchorages and pipeby-passes was under-run, anindividual approval had to be

obtained.To this end,VT carriedout the required tests andcommissioned a report from anexpert. On the basis of thisexpert’s report, the SupremeBuilding Authority of theBavarian State Ministry ofInternal Affairs granted theapproval on an individual basisfor the use of a prestressingsteel with a steel grade fp0,1k/fpk= 1570/1770, as well as for thereduction of the minimumdeflection radii. �

Structural Systems Limited, theBBR Network member inAustralia, is currently working onthe new Melbourne CementFacility Silo in Port Melbourne,Victoria.This state-of-the-artcement storage silo has a capacityof 35,000t and is the latestaddition to Melbourne’s largestcement plant. The facilitycurrently supplies 80% of thecement required by five of themajor ready mix companies inMelbourne.

Loop anchorage of the meridian tendons.

30 CONNÆCT

Structural Systems Limited’s scopeof work on the project was:• Slipform – supply and operation• Post-tensioning – supply andinstallation

• Reinforcement – installationThe on-site set-up of the slipformsystem took 4.5 weeks from startto the commencement of thefirst pour. Pouring of the concrete,fixing of the reinforcement andinstallation of the post-tensioningducts and castings wasundertaken over continuous 24-hour pouring cycles, reducing theneed for unsightly constructionjoints in the external wall.

POURING CONCRETEThe silo was broken into threepouring sections.The first was to the wall thicknesschange where the walls steppedon the inside face from 900mmthick to 450mm thick. The wall

change formed a shelf on theinside of the silo for the precedingprecast concrete panels used toform the cone to sit on.Theinternal cone structure is the basisof the internal loading feature.The

wall changeover took six days tocomplete.The second pouring sequencesaw the start of the post-tensioning.The silo has 72 1906hoop tendons at 1m centres.Thehoops are broken into foursegments and stressed throughfour buttresses.The decision touse heavy duty 3mm thick

galvanized metal-ribbed duct witha ID of 105mm was taken inorder to minimise the risk ofdamage to the empty ductthrough the continuous concretepouring cycle – and also toreduce any problems with strandsjamming in the following post-tensioning strand pushing activity.The required stopping height ofthis second pour was determinedby the weight and the cranagecapacity for the erection of theprecast concrete cone panels.Each panel weighed 26t with atotal of 24 in the bottom sectionand 12 in the top section of thecone, separated with a concretein-situ ring beam.When the desired height wasreached, a PVC waterstop wasinstalled in the top of the wall toalleviate any moisture penetrationmigrating through the wall fromthe construction joint.The third concrete pourcommenced some nine weeksfrom the completion of thesecond pour, thus allowing forcone works within the silostructure.

NEW HIGH SPEEDPUSHERSOn the completion of the thirdconcrete pour, the 72 1906tendons were installed using thenewly developed, computerised,high-speed strand pushersenabling our post-tensioninginstallers to work in an efficient

and safe manner from mastclimbers mounted on all fourbuttresses.The 102m long strandtendons were installed in less than12 days.

STRESSING & GROUTINGOn completion of the strandinstallation the tendons werestressed in a predeterminedsequence to a load of 4,225KNusing a 630t jack.This stage wascompleted in less than ten days.When a project is on a tightschedule, all components must bereliable, user-friendly and readilyavailable – which is why the clientchose the BBR CONA post-tensioning system.The final stage of the post-tensioning was the grouting of thehoop tendons – this activityimmediately followed thestressing/cutting of the tendons,once each tendon had beencompleted.

SLIPFORMINGThe slipform pouring cycles weremanaged in two daily shifts –working 12 hours each. Slipformis a continuously movingformwork, system climbing at arate of approximately 200mm perhour and occupying a totalworkforce of 30 men, includingconcrete placers, on each shift.Structural Systems Limited withits experienced and motivatedworkforce completed the projecton time and within budget.

TEAM &TECHNOLOGY

� OWNERMelbourne Cement FacilityLimited

� CONTRACTORDynamic EngineeringConstruction Co. Pty Ltd

� DESIGNERShedden Uhde

� TECHNOLOGYBBR CONA internal

� BBR NETWORKMEMBERStructural Systems Limited(Australia)

31CONNÆCT

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The team from BBR Network member,KB Spennteknikk AS in Norway, faced an arctic

climate and persistently strong winds to providefoundations for 17 windmills for their client Statkraft.The KjøllefjordWind Project is located 74° North, onMount Gartefjell – 230-300m above sea level – in themunicipality of Lebesby in Finnmark, Norway.Foundations for the windmills consisted of 136 BBRCONA 1906 rock anchors – eight anchors per windmill.The expected average annual output of the wind farm– which opened in October 2006 – is in the region of150GWh, equal to the consumption of around 7500households. �

KJØLLEFJORDWIND PROJECT, NORTHERN NORWAY

Northernextremities

TEAM &TECHNOLOGY

� OWNERStatkraft Development

� CONTRACTORAF Skandinavia AS

� DESIGNERSweco Grøner AS

� TECHNOLOGYBBR CONA rock anchors

� BBR NETWORKMEMBERKB Spennteknikk AS (Norway)

32 CONNÆCT

Pictured here is AngloGold Ashanti Ltd’s, SunriseDam gold mine, which lies some 220km northeast of Kalgoorlie and 55km south of Laverton inWestern Australia. The mine comprises a largeopen-pit operation and underground project withover 12km of development. Gold is located inthree broad settings – gently dipping shear zones,steeply dipping shear zones and gold richbreccias.Rock Engineering has completed many projectsfor both the open pit and underground. Recently,work has included a successful cableboltingcampaign, using thixotropic grout, to stabiliseground conditions so that further productioncould take place on a footwall. Also, degradationand weathering to the transitional zones of the

pit walls has required theapplication of surface support forground control in a number ofcritical production areas. Rolls ofup to 80m in length have beeninstalled within time and budgetrequirements.Seven portals have now beensuccessfully been established forthe underground project. Theinstallation by Rock Engineering ofa fence above the western shearzone portal, plus fibrecreting of thebatter face, has allowed our clientto achieve the full 22.5m verticalbench height.

Extension and remodelling of the metrostation at Sol, in the centre of Madrid, was

needed to accommodate new subway trainswhich will run along Line 3 of the Madrid Metro.Guillermo Molins Roger from BBR Networkmember, BBR PTE, describes his company’s –quite literally – supportive role in the project toextend the length and width of the station.The first step was to build a reinforced concreteslab over the entire excavation area. As this areawas large enough to encroach upon thefoundations of the surrounding buildings, it wasnecessary to install a system to protect thefaçades of the historic listed structures aroundthe site.

EXTENSION OF METROSTATION, MADRID, SPAIN

Load handlingprotects façades

Safely meeting production

BBR Network member, Rock Engineering, hasdeveloped both specialist techniques and purpose-built equipment to keep production on schedule

for mining clients inWestern Australia.

MINING OPERATIONS,AUSTRALIA

33

A rainwater harvesting system was installed to allow the water whichcollects in the gutters to be put to good use – for gardening.

STANDARDS & SAFETYRigorous quality control systems were adopted to ensure that thequality of materials received and used conformed to the standards,while our construction methodology was in keeping with standardengineering practices. Test certificates were regularly obtained andmaintained.All efforts were made to ensure the safety of workers on site byfollowing the industry norms for safety. The noise levels were kept aslow as possible, so that the air force technical personnel were notdisturbed.Our experience of executing this innovative Rs25m project – within atight time frame of 125 days – proved that box-jacking is the mostsuitable approach for the construction of underpasses beneath busyhighways. This technology provides a distinct advantage over the cut-and-cover method in such situations, as construction can take placewithout interrupting the traffic above and the method works wellwithin the constraints of a tight time schedule. �

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TheNational Highway Authority of India(NHAI), through the SID, Indian Institute ofScience, recently entrusted BBR (India) Pvt

Ltd,with the prestigious and challenging task ofproviding an underpass beneath a 6-lane NationalHighway to connect the domestic and technical sideof the Air Force Station at Bangalore – withoutinterrupting the traffic on the Highway.Box-jacking – the most non-intrusive means of tunnelling to constructthe underpass – was used. This method enables traffic flows to bemaintained throughout the construction period and with only minorrestrictions during the brief period of tunnelling.The inconvenienceand cost of disruption to infrastructure and traffic flows experiencedwith traditional construction methods can thus be avoided.

TUNNEL DESIGNThe proposed 36m tunnel consisted of two 3.7m wide shafts for thevehicular traffic. For pedestrians, a 2.7m wide footpath wasconstructed in the middle of the two shafts. The tunnel was to bebuilt approximately 2m below the existing road surface.

CONSTRUCTION ENGINEERINGThe raft portion is critical during construction, as it has to supportthe reaction from jacks while pushing. So a reaction frame wasdesigned by examining jack reaction forces. A 750 x 1950mmreaction beam was considered for the design and a 300mm thick14 x 8.5m raft was considered in the pushing region.Six 6m long segments were cast in a pit on one side of the site andthese were then pushed, carefully and gradually, one after the other –while digging out the ground for the tunnel. Four 500 MT capacityjacks were used. An innovative shuttering system was used wherebyonly partial de-shuttering was required, thus saving time.The approach ramps on both sides had a slope of 1:10. Theexcavation was carried out using excavators and the sides of theexcavation were soil nailed for stability.

YELAHANKA UNDERPASS, BANGALORE, INDIA

New underpass for India’s silicon valley

BBR PTE was asked to design and develop asystem which guaranteed that no differentialmovements could happen during the excavationunder the buildings’ foundations.The system that BBR PTE put in place to holdthe buildings’ façades was based on a set of 32synchronized loading hydraulic jacks controlled bya specially designed control unit and power pack.Each jack had two sensors – one of themmeasuring the ram displacement and the othermeasuring the pressure applied to the jack, thedata easily converted to force. Bothmeasurements – displacement and force – weretransmitted to the PLC of the power pack whichcontrols the whole system.Once on line, the system was able to control thejacks automatically, so if a loss of force in one ofthe jacks were to be detected, the power packpump would increase the pressure inside the jackuntil it reached the value of the load transferredby the buildings’ foundations.This means that, ifthe excavation caused the slab to settle, the

that moment, the load acting onthe jack was the one coming fromthe building and transferred by thepier to the foundation – and thiswas the load that had to bemaintained.

power pack would activate and reset the jack toits correct load state.To tare the system, once the jacks were placedand before the excavation started, the jacks wereloaded until some movement was detected. At

TEAM &TECHNOLOGY

� OWNERMetro de Madrid

� CONTRACTORLínea 3 UTE (Joint venture FCC& CONVENSA)

� DESIGNERFCC Technical Services

� TECHNOLOGYBBR hydraulic jacks andsynchronized power pack

� BBR NETWORK MEMBERBBR PTE (Spain)

34 CONNÆCT

Today, BBR Stay Cable Technology canbe used for the following applications:

� Cable Stayed Bridges have beenbuilt in rapidly increasing numberssince 1950 and have been found tobe especially economical for mediumto long-span bridges from 100 to1000m, where technical andeconomic arguments dictate thissolution. For smaller bridges, otherparameters may be decisive for thechoice of a cable stayed solution –such as reduced depth of deck,construction methodology andaesthetics. BBR Stay CableTechnologyis the ideal choice for the cables.

� Suspension Bridges have been usedsince ancient times and nowadayssuspension bridges with spans close

to 2000m have been built. BBRTechnology can be used for the mainsuspension cables as well as for thehangers.

� Roofs of grandstands, stadiums,aircraft hangars and other lightweightwide-span structures are an idealapplication for BBR Stay CableTechnology.

� Towers for communication facilities,chimneys and antennas, as well aswind power stations can bestabilised using BBR Stay CableTechnology.

R&D & QUALITY ASSURANCEExtensive research, testing anddevelopment efforts place BBR at theforefront in the field of post-tensioningand stay cable applications. BBR also

LEGENDARY BBR STAY CABLE TECHNOLOGY

Staying power

Since the early days of post-tensioning, BBR Stay CableTechnology has been recognised as the most advancedand most reliable system on the market. BBR is not

only the“godfather” and inventor of high fatigue resistant wirestay cables, but has also pioneered, invented and constructedthe world’s first project using modern parallel strand staycables and has invented and successfully applied the world’sfirst carbon stay cables.

In 1971, the Olympic Stadium in Munich, Germany – with its cable supported membraneroof structure – hosted the Games in 1972. Until 2005, the stadium was home toBayern Munich FC, one of the world's premier soccer clubs and record title holder inGermany.The 488 stay cables are comprised of parallel strands, with which BBRpioneered the usage of High Amplitude fatigue resistant strand stay cables. Photos: KevinLazarz

35CONNÆCT

offers a variety of solutions to counter cablevibration – such as the BBR Square Damper andcable surface treatments.To assure the highestquality product, all of the system components aresubjected to the most stringent testing andQuality Assurance procedures, based oninternationally recognised codes andrecommendations.

SUPERIOR FATIGUE & STATICRESISTANCEFor many years, the minimum fatigue test strengthfor stay cable systems has been 160N/mm2 (PTI).More recently, a stress range of 200N/mm2 for2x106 load cycles – in combination with angularrotations at the anchorages – has been adoptedand is now specified by most codes andrecommendations. BBR Stay Cable Technologyhad already fulfilled requirements for such fatiguetesting – decades before these provisions wereconsidered to be state-of-the-art!

DECADES AHEADWhereas many cable suppliers built their firstmajor cable supported structure in the late 1970sand early 1980s, BBR Stay Cable Technology wasused for the first time in the late 1950s and, sincethose days, BBR Stay Cable Technology has beenapplied to over 300 major structures around theworld – including the breathtaking Tatara Bridge inJapan, which has the longest main span to havebeen constructed in the 20th Century. �

BBR world first applications1958 – Wire Stay CableStandard BBRWire Cables are composed of 7mm diameter wires of lowrelaxation grade, with a minimum guaranteed ultimate tensile stress of 1670 or1770N/mm2.Typically, the wire bundle is galvanized and covered with a thick-walledUV-resistant HDPE pipe, and the voids in the pipe are filled with a flexiblecorrosion protection compound.

1968 – Strand Stay CableToday, standard BBR Strand Cables are composed of galvanized, waxed and PE-coated 0.62" (15.7mm) strands of low relaxation grade, with a minimumguaranteed ultimate tensile stress of 1770N/mm2 or 1860N/mm2 inside a UV-Resistant HDPE Stay Pipe.

1994 – Carbon Stay CableThe BBR Carbon Stay Cables consist of CFRP (Carbon Fibre Reinforced Polymer)wires of 5mm diameter covered with thick-walled UV-resistant HDPE pipe.

BRID

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In 1961, the first bridge to be built using parallel wire cables was the pedestrian Schillersteg Bridge across the Schillerstrasse in Stuttgart, Germany.

The Störchenbrücke in Wintherthur, Switzerland –crossing the major east-west axis of the SwissFederal Railway Network – was the world's firstbridge to be constructed using carbon stay cabletechnology.

36 CONNÆCT

Before the reconstructed Sloboda Bridge overthe River Danube in Novi Sad could be

opened to traffic, the authorities requiredextensive load testing to be carried out. A localbrewery was persuaded to help engineers bysupplying 20 identical lorries – each with a fullload of beer! Dr Minas from main contractorDSD Brückenbau GmbH, takes up the story.The Construction Engineering Department ofBelgrade University planned and conducted thetesting on our behalf – in accordance with localstandards. Their two-day programme includedboth static and dynamic testing.Static tests were carried out in seven phases andwere designed to show:� Maximum vertical loading in bridge centre� Maximum torsion loading in bridge centre &

asymmetrical loading

� Maximum loading between thetwo outer cables (2 & 3)

� Maximum loading betweencables 1 & 3

� Maximum load between pylonand middle cable of the backanchorage

� Maximum load of the 60m longapproach bridges

For the dynamic test, a lorry droveover a 10cm high wooden step atdifferent speeds and this showedthat the effect of dynamic loadingon the stay cables/tensioning incross section was negligible.Finally, a comprehensive 138-pagereport from the University statedthat the reconstructed bridge

showed an elastic character and that the capacityof the bridge was actually higher than recom-mended in the original plans. Following receipt ofthe report, the bridge was opened for traffic.

Mulhouse was a pioneering townduring the industrial revolution in

France and today it is leading the way inproviding innovative infrastructure. Thenew bridge over the Rhine-Rhône Canal ispart of the town’s “Voie Sud” masterplanto resolve traffic congestion whilst makingthe town centre more accessible.BBR Network member ETIC was commissionedto carry out the post-tensioning and stay cableworks.The 16m wide bridge consists of one 25mlong span of post-tensioned concrete with BBRCONA internal transversal cables.The thicknessof the slab is 0.64m.The bridge has one central pylon comprising fourmetallic tubes from which emerge six BBR DINA55 stay cables. These are encased in HDPE staypipes and injected with wax.The total length of cable used was 170m –approximately 24.3m to 31m for each unit.Thecables were prepared in the workshop anddelivered to site for final installation andtensioning.

TEAM &TECHNOLOGY

� OWNERVille de Mulhouse

� CONTRACTORARCADIS, Strasbourg

� DESIGNERARCADIS, Strasbourg

� TECHNOLOGYBBR CONA internalBBR DINA stay

� BBR NETWORK MEMBERETIC

PONT DE LA FONDERIE, MULHOUSE,FRANCE

UnlockingTHETOWNCENTRE

LOADTESTING, SLOBODA BRIDGE, SERBIA

Synchronised trucking

37CONNÆCT

SECOND LONGEST &Environmentally

Friendly �

THE GREEN BRIDGE, BRISBANE,AUSTRALIA

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38 CONNÆCT

The project client, Brisbane City Council, linked thebridge into the pedestrian drop-off areas, footpath,bicycle path, bus and rail network and local areaparking zones, as part of an integrated strategyfor encouraging public transport for all journeysthat include the bridge and throughout Brisbane.

CONSTRUCTION ELEMENTSThe bridge deck is 20m wide, 520m long with amain span of 185m and back spans of 92.5m.Thestructure has two 70m-high H-shaped towers inthe river.The structural portion of the towers is

reinforced, cast in situ concrete,topped with an architecturalportion of thin precast panels overa steel structure.

STAY CABLESThe 64 stay cables are between20m and 100m long and use BBRCONA Stay Cable technology.Each stay cable consists of 31 or 37parallel 15.7mm diameter seven-wire strands enclosed in a UV-

resistant HDPE stay pipe – in a selectedarchitectural dark grey colour. The stay pipeincorporates spiral ribs to act against wind andrain induced vibration.The strands are galvanized, waxed and individuallysheathed with a continuous and wear-resistantcoating, providing each strand with a tripleprotection system. In the anchorage zone, thestrand bundle passes though a deviator andspreads out towards the high fatigue resistantanchorages, where each strand is individuallyguided and locked with high fatigue resistant grips.Ring nuts screwed onto the anchor heads transferthe cable loads by contact pressure to thesupporting bearing plates.The individual strands inside the anchorage areprotected by a corrosion-inhibiting compound.Finally, the anchor head is covered by a protectioncap injected with corrosion-inhibiting compound.With this system, the anchorage is fully en-capsulated with a multi-barrier protection system.

SUPPLY & INSTALLATIONThe supply and installation of the stay cable systemwas undertaken by Structural Systems Limitedusing the state-of-the-art, strand-by-strand install-ation method. Anchorages were first installed inthe tower and the deck.The HDPE stay pipe wasthen hung between the two anchorages, using twomaster strands, and used as a guide for subsequentstrand installation. The strand was positioned atdeck level and pulled up through the stay pipe tothe upper anchorage using a stay cable strandpuller, positioned behind the upper anchorage.

Environmental campaigners often claimthat new roads and bridges lead tohigher traffic volumes – that they

effectively generate additional traffic byproviding greater road capacity. BBR Networkmember Structural Systems Limited reportsthat in Brisbane, Australia, the Green Bridgereverses this criticism by banning privatevehicles altogether – and being entirelydedicated to public transport, cyclists andpedestrians.The aptly named Green Bridge isAustralia’s second longest cable stayed bridgeand provides bus, pedestrian and bicycle accessvia its two bus lanes, dedicated cycle way andfootway.

39CONNÆCT

STRAND TENSIONINGEach strand was tensioned immediately afterinstallation, using the BBR isostress tensioningmethod, ensuring an equal force distributionamong the strands of an individual cable.Compact multi-strand jacks were used for thefinal adjustment. All stressing was completed fromthe tower, ensuring a more elegant deck detail.Each individual strand installed in the cable systemcan be re-stressed at any time during or after theinstallation – allowing not only for re-stressing, butalso for the selective removal, inspection orreplacement of individual strands.

STAYS SUPPORT CONSTRUCTIONThe composite deck consists of steel grillageswith precast reinforced concrete planks and in-situ concrete stitch joints, in-situ concrete barriersto protect the stays against vehicle impact andarchitectural features on the cycle way andfootway.The bus lanes have a bitumen overlay and theentire bridge is designed to accommodate thepossible addition of light rail in the future,including a substantial additional concrete overlayto accommodate the rails.The bridge was built using the balanced cantilevertechnique from both river towers simultaneously.At both towers, deck grillages were erectedalternately on each side of the tower, with cablestays reeved and stressed progressively to providethe appropriate support to the deck – duringconstruction and permanently.After each deck steel grillage was bolted inplace, the initial stay installation took place andthe stay stressed to the minimal load to supportthe grillage.The next stage was installation of theprecast and stitch concrete. After the stitchreached the required strength, the second stagestressing was carried out to support the steeland concrete – and to achieve the requireddeck levels.

FINAL DECK LEVELLINGAfter installation of barriers anddeck bitumen, the third stagestressing took place to achieverequired final deck levels.The entirebridge design, including the staycable system, includes provision forfuture stressing to accommodatelight rail at a later stage.The bridgeand approach works are expectedto open in early 2007.

PROFESSIONAL TEAMMain contractor, John Holland, tookon a design, construct and maintaincontract for client Brisbane CityCouncil.Structural Systems Limited wasawarded the design, constructionengineering, materials supply,equipment hire, labour, supervisionand expertise for the fabrication,installation, stressing, finishing andmaintenance of the stay cables. �

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TEAM &TECHNOLOGY

� OWNERBrisbane City Council

� CONTRACTORJohn Holland

� DESIGNERGHD, IBT

� BBRTECHNOLOGYBBR CONA stay

� BBR NETWORKMEMBERStructural Systems Limited(Australia)

40 CONNÆCT

NAVIA RIVERVIADUCT,NORTHERN SPAIN

BBR triumph onbowstring arch bridge

This significant bridge is situated in Asturias, in northern Spain and was inaugurated inJune 2006.The main characteristics of the Navia River Viaduct are the two 160mcentral spans held up by two arches built on the prestressed deck.The arches are

each composed of 17 pairs of parallel stay cables, which descend through the bridge deckto the piers at either end of the arches. David Olivares of BBR PTE describes how the staycables were installed and tensioned.

41CONNÆCT

The bridge has 11 spans and isbuilt with precast segments –making a finished length of905.4m in total.The precastsegments were placed using thecantilever method and by meansof a self-launching girder.

PRESTRESSED DECKThe deck was prestressed withmore than 900t of post-tensioned steel, including ex-ternal and internal BBR CONAtendons, and was undertakenwith an hydraulic auto-propelledrobot which placed the stressingjacks inside the deck.The deck interior prestressing ismade up of 356 BBR CONA1906, 864 BBR CONA 2406and 52 BBR CONA 3106anchorages. Over the perm-anent piles there are 30 BBRCONA 2406 and 132 BBRCONA 705 anchorages.Alongside the two arches, thereare 12 BBR CONA 4206external prestressing tendonstotalling 320m in length. Also, inthe arches anchorage zone,there are a further 64 BBRCONA 2406 anchorages.The deck positioning was carriedout using four 1700t vertical andeight 160t horizontalsynchronized jacks, equippedwith force and displacementinstrumentation.

ARCH CONSTRUCTIONThe arches consist of a metallicbox filled with concrete andtheir anchorage bases to thedeck have 84 bars Ø40 type935/1030.The bars werestressed before the stay cableswere hung from the arches.There are 68 BBR DINAhangers which are joined to the

arches by means of BBR Pin-Open Sockets made of caststeel. At the other end of thecable, the movable anchoragepasses through the deck to theunderside, where each pair ofstay cables were stressed withtwo 300t jacks at the same time.

STAY CABLESEach of the 68 BBR DINA staycables was identified and markedbecause they were associatedwith their own individual caststeel piece.The installation beganby hanging the cast pieces in thearches using a raising tool fromwhich the pieces weresupported while the pin waspartially inserted.The BBR DINA cables werefixed to the sockets by means oflocking bolts. A crane was usedto hang the stay cables from thecast pieces and lifted them untilthe end lower cable could beinserted into the form pipe.Then the cables were lifted sothat the upper cable ends couldbe fixed into the anchorage.

The final position of the staycable’s active anchorage, afterstressing, was calculatedaccording to its lengthening.Thatis because the force applied tothe cables changes, dependingon its relative position, lengthand temperature.When the staycables were in position, in manycases the stressing sleeveoverhung from the support plateand the lock nut could beturned. Conversely, the longeststay cables which hadlengthened considerably, had thestressing sleeve inside the formpipe before stressing. So the locknut was turned after thestressing operation.

STRESSING EQUIPMENTThe equipment used to stressthe stay cables included a jackextension which rested on thesupport plate and allowed thelock nut to be threaded duringthe cable stressing, a jack with a300t force at 700 bars and aload cell to show the forceapplied to the stay cables.To

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TEAM &TECHNOLOGY

� OWNERMinisterio de Fomento

� CONTRACTORFCC Construcción, S.A.

� DESIGNERTechnical Services of FCC Construcción, S.A.

� TECHNOLOGYBBR CONA external, BBR CONA internalBBR DINA stay, PT bars

� BBR NETWORK MEMBERBBR PTE (Spain)

stress the cables, a pulling rodwas attached to the stressingsleeve.

FINAL STRESSINGOnce the 68 stay cables werestressed and the projecting cableextremities were filled with wax,the two central temporary pilesunder the arches were removedusing four 230t heavy liftingjacks.The heavy lifting unit’s jackswere synchronized by acomputer and the lowering wasachieved with great precision. �

42 CONNÆCT

GEOMETRY & CONFIGURATIONThe dimensions of the arch at its base are 80mlongitudinally and 20m transversely. The two archplanes are inclined inwards at 17° from thevertical with 13 hangers on each side.The overall width of the deck, made of compositesteel, is 15.1m. The 290mm thick RC slab issupported on steel cross girders at 4.8m spacing.These cross-girders are supported by twolongitudinal steel edge girders hung from hangersat 4.8m spacing.The initial portion of the arch between the pilecap and deck level is formed by post-tensionedreinforced concrete buttresses for betterdurability in the splash zone. The rest of the archconsists of a steel box of 1m x 1m cross-section,with 30mm thick plates. The steel arch came insections which were butt-welded, forming acontinuous curved arch.

CONSTRUCTION METHODThe construction method enabled prefabricationof the steel arch components offsite at a steelfabrication yard in Malacca, Malaysia. The steelbox sections for the arch were fabricated to amaximum length of 12m for easy delivery bytrailers to the assembling site at Lumut Port,Perak.At the port, a flat top barge was moored to theshore for transporting the arch to the site. A150t crane was used to lift and assemble thesteel deck sections on top of the barge.Temporary steel towers were erected on top ofthe barge to support the arch segments. The

steel segments were lifted intoposition starting from bottom totop. After an alignment check, thejoints were butt-welded.Prefabricated BBR DINA hangerswere installed using a small crane.The lower anchor was lifted into

position before the upper anchor was secured. Astressing jack was used to stress each hangerfrom the bottom to take up the initial sag of theinclined hanger. The force in the hanger had tobe below the force that would lift the edge girderfrom the temporary supports.Meanwhile at the bridge site, the concretebuttresses were being constructed on top of thepile caps. Each buttress was inclined in bothdirections. It was cast in several stages up to thefourth cast. The fifth – and final – cast was toprovide adequate clearance for the erection ofthe prefabricated steel arch. BBR CONA 1906post-tensioned tendons were used to take careof the bending and deflection of the inclinedbuttress during construction.

Chee-Cheong CHANG from BBR Construction Systems (M) Sdn Bhd reports onthe complex construction and heavy lifting operation of the arch bridge whichforms part of a 2km access bridge from the Kedah coast to Bunting Island. It has

an 80m span and 9m depth navigation channel.The challenge was to design and construct a fixed arch bridge which was aestheticallypleasing, whilst buildable in seawaters – yet still economical!The arch was made of steel for ease of fabrication and assembly. The assembled arch on abarge was vertically lifted into position using BBR heavy lifting strand jacks.

STEEL ARCH BRIDGETO BUNTING ISLAND, KEDAH, MALAYSIA

Time and tide waitfor no man!

Facts & FiguresLoad per lift point = 105t

Capacity of strands= 12 x 26.1 = 313t

Factor of safety = 3.0

43CONNÆCT

For the erection of the arch, temporary steeltrestles were erected on top of the completedconcrete deck near the arch buttress. The trestleswere used for supporting the jacks for heavylifting of the arch.The barge, with the prefabricated arch on top,was slowly towed in between the two pile caps.The steel arch bridge was raised vertically to itsfinal level using strand lifting techniques.Upon securing the arch to the deck, the buttressrebars were coupled and remaining portion (fifthcast) of the concrete arch buttress was castthereby joining the steel arch to supporting piles.After the concrete had attained sufficientstrength, the forces on the strand jacks werereleased, thereby transferring the bridge load tothe arch buttress.Precast deck segments were installed over thesteel cross-beams. A topping concrete was usedto make up a total structural thickness of 290mm.

FOUNDATIONSBasically, it is a steel arch bridge with the endsfixed into the pile cap. However, because of theheavy lifting method of construction, thehorizontal thrusts at the foot of the arches couldbe reduced.Stage 1 – During constructionConcrete buttress together with circular piers andapproach beams was analysed as a frame tosupport the steel arch. During the constructionstage, this frame is an individual frame taking itsown weight and load of the steel arch as a pointload at the tip of the buttress. All these loads willinduce permanent stresses, moments andreactions within the frame structure.Stage 2 – In serviceWhen the steel arch was lifted in place, it neededto be permanently fixed to the buttress throughfixed joints. All those loads applied at a later stage– like concrete deck slab, SDL and LL – will betransferred to the foundations through the fixedarch action. In design, all these resultant stressesand moments need to be added to the residualstresses and moments from the constructionstage, that is, before the arch was fixed inposition.

HANGERSThe hangers were fabricated using the BBR DINAsystem. Each hanger is made up of 42 wires of7mm diameter with tensile strength of1670N/mm2, providing a breaking load of 270t.For design, the maximum stress in the wire fromall loads in service is restricted to 45% UTS(ultimate tensile strength).

At each end of the wire, a buttonhead was cold-formed using a BBRbutton-heading machine. It wasthreaded and anchored by the fullythreaded anchor head. This systemprovides good fatigue resistance.The wires were protected with anexternal high density polyethylenepipe (HDPE) and wax.Dead end anchorage was selectedto be at the hanger top, as nostressing needed to be done here.Live end anchorage was providedat the hanger bottom to allowstressing. By designing the anchorbearing plates welded on top ofthe longitudinal edge girders,stressing could be carried out easilyon top of the bridge.Once the steel arch was lifted to itsfinal position, the deck levels weresurveyed. The forces in thehangers were fine-tuned to target

achievement of the designed deck levels, whilechecking that the forces in the hangers did notdeviate significantly from each other. By usinghydraulic jacks and a stressing chair, the deck wasraised or lowered by adjusting the locknut to thethreaded BBR DINA anchor heads.

HEAVY LIFTINGLifting pointThe steel arch bridge weighed 420t. Four liftingpoints – one at each corner of the bridge wereneeded. At each lift point, a 260t strand jack witha 1206 strand bundle was used.Vertical lifting and then sliding into place wasconsidered. As the deck area was small, it wouldhave required extensive and complex steeltrestles partly sitting on the deck and partly onthe pile cap. So, a simple direct vertical lift waschosen. This method also loaded the buttressesdirectly and equally.The difficulty was in locating the lifting points. Ifthe point were to be directly on the arch, thelifting point on the trestle would be outside thedeck in both directions. This was solved bylocating the four lifting points on the first cross-beam of the deck. Then the lifting point wouldbe cantilevered in one direction only from thedeck. The connection of this first cross-beam tothe arch was strengthened to take the temporaryload arising during lifting. Lifting directly from thearch had another disadvantage which was that thelifting point elevation would be higher andrequired a higher and more costly trestle.Temporary trestleAt each lifting point, a temporary steel trestle wasinstalled on top of the deck, close to the concrete

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Lifting cyclesequence1. Wedges were locked inupper chuck.

2. Load was raised to adistance equal to theavailable jack stroke.

3. Lower chuck was beingclosed and the upperone opened.

4. Main jack was retractedand the upper chuckmoved back to itsinitial position, readyfor next cycle.

“THE FORCES INTHE HANGERSWERE FINE-TUNEDTOTARGETACHIEVEMENT OFTHE DESIGNEDDECK LEVELS”

�

44 CONNÆCT

buttress. It served as a temporary support pointfor the jack and working platform. As thestructure was cantilevering over the deck, tiedown bolts were installed to hold down thestructure against overturning.Lifting systemThe BBR Strand Lifting system was used to dothe lifting. Each lift point had a main jack, a pair oflocking chucks (upper and lower), a dead endanchor, a main pump and a chuck pump.The main jack had a centre hole through whichthe 1206 strands passed. The jack nose wasremoved and the jack was placed vertically withits piston (ram) stroke movement at the top. Themain pump was used to push the main jack’spiston out or retract the piston to its originalposition.Chucks were used to grip – or release – thestrands. The chuck pump hydraulically locked andunlocked the chucks, using wedges, during thelifting cycle.Dead end anchorThe anchor was fixed to the soffit of the firstcross-beam of steel deck. Upon parking thebarge, each strand was locked into the dead endanchor with spring-loaded wedges to ensurestrands were locked at all times.Having towed the barge from Lumut to the seaoutside the pile caps, the date and time of thelifting needed to be decided. Ideally, the liftingwas to be done when the sea was most gentleand at a time of lowest tidal height difference.But due to time constraints, the lifting took placeon the date where the tidal height difference washighest – 1 July 2004.The time to lift was chosenas 1500 hours – when the tide was going out.Parking the bargeThe team had to ensure that, once the barge wasparked between the pile caps, the lifting would becarried out promptly. This was because the spacebetween the barge and pile cap was tight. Roughsea might push the barge and arch against thepile caps and they would be damaged.

By using tugboats and winches, thebarge was manoeuvred in betweenthe pile caps. Next, the temporarytie-downs on the arch longitudinaledge girders – needed fortransporting the arch – wereremoved to enable lifting from thebarge.Lifting the archAfter the barge was parked, strandswere threaded through the firstcross-beams and locked into thedead end anchors. All the strandswere cut to equal length to ensurethey would have same tensionupon lifting. By monitoring thepressure gauges at the four liftingpoints, the forces were increaseduntil the arch was lifted from thebarge.Lifting was carried out inincremental heights of 200mm forall four points simultaneously. Thiswas achieved manually by having ateam leader with four operatorscommunicating with walkie-talkies.Each 200mm was further dividedinto two incremental lifts of100mm each. After several liftcycles, survey instrumentation setup on Pile Cap 68 would check thedifference in levels at the four

points. The difference in levels was kept to 50mmmaximum.To equalise the levels at the four points, theamount to jack-up was determined to therequired values and then jacked-up at the sametime. After this, it went back to normal jacking of200mm stroke.Lifting continued from 3pm to 6pm on the firstday, achieving a 3m lift height. The rate was1m/hour.On the second day, lifting continued until the fullheight of 7.6m was reached – at which point, thejacks and chucks were locked. Then the arch wassecured against lateral movement by connectingthe steel deck to the concrete deck.Load transferAfter securing the arch, the last portion of theconcrete buttress (fifth cast) was constructed.When it had gained strength, after 14 days, thejacks were released to transfer the force from thehanging system to the buttress. The operationwas completed by lowering the jack ram graduallywhile keeping the lower chuck open to allowstrands to move downwards. �

TEAM &TECHNOLOGY

� OWNERPublic Works Department

� CONTRACTORGamuda Berhad

� DESIGNERBBR Construction Systems (M) Sdn Bhd

� TECHNOLOGYBBR Heavy Lifting SystemBBR DINA stayBBR CONA internal

� BBR NETWORK MEMBERBBR Construction Systems (M) Sdn Bhd

“IDEALLY,THE LIFTINGWASTO BE DONEWHENTHE SEAWAS MOSTGENTLE AND AT ATIMEOF LOWESTTIDALHEIGHT DIFFERENCE. “

45CONNÆCT

DEVENTER BRIDGE, OVERIJSSEL,THE NETHERLANDS

Strengtheninginnovation

MRR

Deventer is a town inthe Dutch province of

Overijssel and is largelysituated on the east bank of theRiver Ijssel. The BBR VT CONACME Band System was used for

strengthening work on the nearbytwin parallel bridges which carry the

A1 motorway over the Ijssel. �

46 CONNÆCT

Each bridge has a total length ofapproximately 1100m and is divided intotwo approach bridges and the central

bridge over the river.This project comprises thestrengthening of both bridges.The east approachbridge is 280m long and the west bridge is 450mlong. Both bridges were built with pre-castsegments and, in cross-section, are of double boxgirder construction. The central part of thebridge – with a 150m main span – was builtaccording to the free cantilever method.Rijkswaterstaat, the Dutch Ministry of Transport,Public Works andWater Management, decided tostrengthen the bridges with external post-tension-ing tendons, as well as other rehabilitation measures.The strengthening was necessary due toincreased traffic loads and the need to use safetylines for traffic during the daily traffic jams.

DESIGN AT TENDERConstruction contractor Heijmans Infra selectedDSI Netherlands as partner for the prestressingworks.The original design was based on a 19-strand system, with few further explanations aboutthe corrosion protection system. A rough appr-aisal showed a prestressing steel quantity of 530t.The tender process would culminate in a technicaland commercial assessment of the bids submitted.

DSI CHOOSES BBR VT CONA CMEDSI was responsible for working out a conceptfor the external prestressing system and chosethe BBRVT CONA CME Band System with 16Dyform strands with a cross-section of 165mm2

and tensile strength of 1820N/mm2.Rijkswaterstaat approved the judgment of DSI bydesignating the quotation as best proposal in thetechnical competition – their success wascompleted by also winning the commercial bid.

CONSTRUCTION STAGEMaterials delivery started in late October 2005.At the end of January, stressing of the firstapproach bridge started. Mostly, it was necessaryto stress with four jacks, simultaneously, because

steel elongation indicates that the friction issimilar to stressing the whole tendon at once.The strengthening of the following threeapproach bridges was carried out subsequentlyand the job was completed in July 2006.

COMPETITIVE ADVANTAGEThe BBRVT CONA CME Band System provedto be a very competitive alternative – theadvantages far outweighed the seemingly highermaterial costs.The prestressing concept proved tobe a solid solution. The Band for the BBRVTCONA CME System is manufactured for the BBRNetwork under patent by VORSPANN-TECHNIKGmbH & Co. KG.

“OVERALL, ITWAS GREATEXPERIENCE – A GOODTECHNICALAND ECONOMICAL SOLUTION,DEVELOPED BY INTERESTINGDISCUSSIONS AMONG ENGINEERS,WAS NOT SUPPRESSED BY RIGIDINTERPRETATION OF STANDARDS”

The BBR VT CONA CME Band System:Key decisive factorsTIGHT SCHEDULEThe construction period was an important factor because of the tight schedule.The factory-provided corrosion protection system reduces the additional workon site to a minimum. Secondly, the BBR VT CONA CME Band System does notlimit the tendon length. In addition, with a lower friction value, it was possible toextend the average tendon length by about 40%. Both factors led to a veryattractive installation time for the external tendons.

WINTER WORKThe contractor was interested in taking advantage of the fact that the post-tensioning works within the box girder could be carried out during the winter.Asthe corrosion protection element of the system is a substantially grout-freesolution, it is not affected by low temperatures.

DYFORM CHARACTERThe geometry of the cross beams meant that economically it was almostimpossible to avoid a minimal radius of curvature of 3m. It was possible toconvince the client to use the Dyform strand which showed excellentcharacteristics during deviation and deflection tests.

TENDON REDUCTIONEven the addition of a further line of tendons, as a result of the restriction to16 strands in the band system, was not seen as a disadvantage.The critical impactof the anchorage zone was reduced by sharing out the anchorages in severalcrossbeams. The extension to the average tendon length meant that the totalnumber of tendons was reduced by 20%.

INNOVATIVE SADDLESOur package was completed with an innovative solution for the saddles – theextraordinary requirement for 1000 pieces permitted a new production method.

PATENT & PROOFAn additional plus was that the patented BBR VT CONA CME Band System hadalready been successfully applied in Netherlands in 2001.

of the fragile structure. In individualsituations, there was insufficientspace available for standard jacks.Then the tendons were stressed,band-by-band, with a smaller jackwhich revealed an additionaladvantage of the Dyform strand.The achievement of the expected

47CONNÆCT

Shiraishi uses the new seismic strengtheningsystem for reinforced concrete water storagefacilities called ECO-REFRE (Existing ConcreteStructures-Refresh). ECO-REFRE was developedand first applied in 2004, as a repair andstrengthening system for existing concretestructures, such as water reservoirs anddistribution facilities. The system involves theinstallation of external cables, both horizontally

and vertically, outside of thestructure – the prestressing force istransferred two-dimensionally.This new technology enablesshorter timescales and reducedcosts when compared withtraditional systems which involvewall and column thickening works.In addition, strengthening work

can be performed while the facility is beingoperated and capacity does not change.The Ushigase Water Reservoir is a box-shapedfacility of 50m x 30m x 6m.The strengtheningwork was completed using the ECO-REFRESystem, applying BBRV system tendons(12 wires 7mm diameter) in four tiers and withanchor stressing. The stressing anchorages andfixed anchorages were placed at 27 points.Special measures were applied to counter theeffects of the soil pressure induced byearthquakes which results in deformation of theshorter sides. Protrusions were placed on thetendons installed in the top tier of the shortersides, in order to provide deflection force. �

MRR

USHIGASEWATER RESERVOIR

Seismic strengtheningWITH BBRVThe UshigaseWater Reservoir was built in 1987 as a

governmental water facility located on KyushuIsland, southern Japan. The reservoir required seismicstrengthening because of ageing, reports Seiichiro Ogawaof the Shiraishi Corporation which was contracted tocarry out this work.

TEAM &TECHNOLOGY

� OWNERKumamoto Prefecture

� CONTRACTOROkubo Kensetsu

� CONSTRUCTIONShiraishi Corporation

� TECHNOLOGYBBRV System

� BBR NETWORK MEMBERJapan BBR Bureau (Japan)

48 CONNÆCT

The Pan Island Expressway (PIE) and the EastCoast Parkway (ECP) are vital thoroughfares –both of which serve Singapore’s Changi Airport.The PIE is the oldest and longest of Singapore’sexpressways and extends for around 41km alongthe length of the island, connecting Tuas in thewest, to Changi Airport in the east. Built almostentirely on reclaimed land, the ECP runs for some20km along the south eastern coast and has aninterchange with the PIE at the Changi Flyover.As the bridges and flyovers had to remain opento traffic at all times, only limited lane closure at

night was allowed to carry out theworks. In addition, as the workswere mostly on expressways, safetywas a high priority and truck-mounted attenuators weredeployed whenever lane closurewas carried out.To provide access to the bridgesand flyovers, boom lifts and

working platforms were used.Where suitable,boom lifts were parked on the hard shoulders toprovide access.Where platforms were suitable,they were suspended from the bottom of thedeck slab and spanned across roads andwaterways.

SUPERSTRUCTURE STRENGTHENINGLocations that required strengthening of thesuperstructure by external prestressing were at

Repairs in live traffic

Road bridge upgrade locations� Eunos Flyover – Paya LebarWay (PIE) across Jalan Eunos� Bridge on PIE – across Bedok Canal� Bedok North Flyover – bridges on Bedok North Road across PIE &

slip road� Bridge on Upper Changi Road East – across Bedok Canal� Metal culvert – near lamp post #200 onTampines South Flyover Exit 4B� Paya Lebar Flyover – Paya LebarWay (PIE) across Paya Lebar Road� Tampines South Flyover – bridge on Simei Avenue across PIE &

bridge on Tampines Avenue 5 across slip road from PIE� Changi Flyover – bridge on PIE across ECP� Tanah Merah Flyovers – bridges on Xilin Avenue across ECP� Laguna Flyover – bridges on Bedok South Avenue (1 across ECP)� Marine Parade Flyover – bridges on Still Road South across ECP

including ramp structure

John Mo of BBR Construction Systems Pte Ltd, the Singapore-based BBR Networkmember shares some details of their extensive bridge and flyover upgrading project for

the Land Transport Authority – under live traffic conditions – which his company hasrecently undertaken on and around two of Singapore’s major highways.

ROAD BRIDGE UPGRADING PROJECT, SINGAPORE

TEAM &TECHNOLOGY

� OWNERLand Transport Authority

� MAIN CONTRACTORSingapore Piling & Civil Engineering Pte Ltd

� DESIGNERParsons Brinckerhoff Pte Ltd and MaunsellConsultants (Singapore) Pte Ltd

� TECHNOLOGYBBR CONA, MRR range

� BBR NETWORK MEMBERBBR Construction Systems Pte Ltd (Singapore)

Bedok North Flyover, Upper Changi Road Eastacross Bedok Canal, Paya Lebar Flyover andTampines South Flyover.The objective was toincrease the load capacity rating of the bridgesso as to cater for heavier vehicles in the future.

CFRP STRENGTHENINGAccess openings were created at the soffit ofbox girders. CFRP (carbon fibre reinforcedplastic) was installed beside the openings forstructural strengthening purposes. In addition,CFRP was also installed on piers forstrengthening.The locations where CFPR wasused were Paya Lebar Flyover, Eunos Flyover,Changi Flyover, Bedok North Flyover andTampines South Flyover.

ELASTOMERIC BEARINGSElastomeric bearings at Eunos Flyover and thePIE across Bedok Canal were replaced, while

those at Bedok North Flyover andTampines South Flyover wererehabilitated.

EXPANSION JOINTREPLACEMENTThe existing expansion joints wereremoved and replaced withasphaltic plugged joints at the PanIsland Express across BedokCanal, Bedok North Flyover,Tampines South Flyover, ChangiFlyover,Tanah Merah Flyovers,Laguna Flyover and Marine ParadeFlyover.

PROTECTIVE COATINGSAnti-carbonation protectivecoatings were applied to all thebridges and flyovers.

JET GROUT PILESFor the metal culvert near lamp post #200 onTampines South Flyover, Exit 4B, jet grout pileswere used to strengthen the ground and a newconcrete lining was constructed within theculvert. BBR proposed this alternative designand method to avoid construction of a newbridge deck over the culvert and, thus, extensivetraffic diversion, as the culvert is located belowa busy expressway. Furthermore, there werenumerous water and telecoms services –including fibre optic cables – above the culvertand below the expressway. A successful resultwas achieved despite having to maintain a cross-sectional area reduction of not more than 12%for the culvert – and working in a confinedspace where the headroom inside the culvertwas only 2m. �

49CONNÆCT

Construction work has been phased toaccommodate the All England LawnTennis ClubChampionships each summer. Last year, the mainstand around the Centre Court was demolishedto level 1 and a new seating arena is beingconstructed, ready for the 2007 Championships.This will increase the seating capacity and includenew media commentary boxes.Later this year, the new roof will be erected overthe Centre Court in time for the 2008Championships and, finally, in 2009, the new slidingroof section – which will cover the centre courtplaying area – will be installed.During the design stage, it was found that anumber of beams would need to bestrengthened – firstly, to cope with the weight ofdemolition equipment being used at the earlystage of redevelopment and, secondly, toaccommodate the new loads which will beimposed on the structure by the new roof design.The design of the strengthening has beenproduced by Capita Symonds, using FRP (fibrereinforced polymer) strengthening systems. TheRemedial Division of Structural Systems (UK) Ltd

is undertaking the applicationprocess.Due to the complexity of the initialdesign, changes have been made ininstances where the original plansdiffered from the “as-built”structure. However, the goodworking relationship betweenGalliford Try, Capita Symonds andStructural Systems (UK) Ltd willensure that the work programmewill be completed on schedule forthe AELTCC to hold the 2007Championships as planned. �

MRR

ALL ENGLAND LAWNTENNIS & CROQUET CLUB

Raising the roofTEAM &TECHNOLOGY

� OWNERAll England Lawn Tennis & Croquet Club

� CONTRACTORGalliford Try Construction Ltd

� DESIGNERCapita Symonds

� TECHNOLOGYMRR range

� BBR NETWORK MEMBERStructural Systems (UK) Ltd

Over the next three years, main

contractor Galliford Try will be

progressively redeveloping the Centre

Court at the All England Lawn Tennis

Club in Wimbledon. BBR Network

member,Structural Systems (UK)

Ltd, is carrying out strengthening works

to the superstructure.

50 CONNÆCT

The new 385MW combined cycle gas turbinepower plant is located next to the existing HuntlyPower Station, adding significant capacity to thestation’s current output of 1050MW.Commissioning was completed in December2006 and it aims to contribute to the steady 2%to 3% annual increase in demand for electricitynationwide.

MINIMAL TRAFFIC INTERRUPTIONBBR Contech was involved in strengthening threebridges on the heavy haulage route – the StStephens overbridge at Great South Road, theMangatawhiri Stream bridge and theWhangamarino bridge. All are on State

Highway 1 – between the Port ofAuckland and the power station –and carry significant traffic loadsevery day, which meant much ofthe work had to be done at nightwith one lane closed to ensureminimal interruption to traffic.

WHANGAMARINO RIVERBRIDGEThe strengthening of theWhangamarino River bridgeprovided some unique tests for theteam, including the challenge ofaccessing the underside of the deck

units. BBR Contech solved the issue by designinga suspended scaffold, which was assembled onthe banks of theWaikato River before beingtowed upriver on flotation devices and hoistedinto position.Working at night and section-by-section, the teamstrengthened 33 deck beams and two pier beamsusing a combination of BBR CONA multi-strandand bar externally post-tensioned tendons, whoseanchorages needed to be installed under thebridge and bolted through the deck. FRPcomposites were also used to strengthen theprecast concrete deck units at the location wherethe anchorages were bolted through the deck.Even though the strengthening measures wereonly required for the short term, all tendons andanchorage components received full permanentcorrosion protection so that the upgraded bridgecan continue to provide full-strength service forother heavy loads well into the future.

Uniquechallenges

TEAM &TECHNOLOGY

� OWNERGenesis Energy

� MAIN CONTRACTORBBR Contech

� DESIGNERConnell Wagner Ltd

� TECHNOLOGYBBR CONA external, MRR range

� BBR NETWORK MEMBERBBR Contech (New Zealand)

A$530 million project by Genesis Energy to upgradeits Huntly Power Station has affected much more

than the site itself – it has also affected the heavy haulageroute that leads to it. Paul Wymer and Hugo Jackson ofBBR Contech report that equipment required for theupgraded facility is so heavy that several bridges requiredstrengthening to cope with the load. In the case of oneturbine being delivered from Mitsubishi Corporation, thismeans an all-up truck weight of nearly 500t!

HUNTLY POWER STATION UPGRADE,NEW ZEALAND

“The project required a well co-ordinated team and BBR Contechoffered a pragmatic, solutions-basedapproach” says Richard Pearce,Genesis Energy’s e3p (EnergyEfficiency Enhancement Project)Project Manager. “BBR Contech wasresponsible for implementingConnellWagner’s engineering designand, wherever challenges, arose BBRContech had proposed solutionsready at hand – they are a greatcontractor to work with.”

51CONNÆCT

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TATARA BRIDGE, JAPAN

Realising dreamsAROUNDTHEWORLD

The Honshu-Shikoku Expressway, consisting of three routes linking two main islands,Honshu and Shikoku, across the Seto Inland Sea, is a massive project aimed to formpart of the trunk road and railway network in Japan.The total length of these roads

is approximately 164km. Piotr Krawczonek of BBRVT International Ltd tells the story of theconstruction of a crucial part of this scheme – Tatara Bridge – which has set a technologicalbenchmark for long cable-stayed bridges around the world. �

52 CONNÆCT

In 1973, the bridge had originallybeen planned as a suspensionbridge, however due to itslocation – in the Seto Inland SeaNational Park – the plan wasmodified. In 1989, rethinking ofthe topographical andenvironmental constraint area –as well as current technologicaladvances in long-span bridgedevelopments with computer-based structural analysis –resulted in a change of design toa cable stayed bridge with thesame main span. Consequently,less excavation in the nationalpark area was required, thusdecreasing the environmentalimpact on the surrounding area– with the added benefits oflower construction costs and ashorter construction period.

BRIDGE CONSTRUCTIONErection of the bridge started inApril 1993 and took a littlemore than six years. Notemporary support was requiredin the water when erecting thegirders. Girders were lifted upfrom the sea by a travellingcrane, positioned at the forwardedge of the girder overhang, andthe work relied on balancebetween the side and maingirders at the tower.Construction was accomplishedwithout any accidents – althougha typhoon did come along whilethe centre span was at itsfurthest extension, with theinstallation of the remaining finalsegment.

ENGINEERING DESIGNTatara Bridge is a hybrid cablestayed bridge consisting ofconcrete girders in the sidespans (270 and 320m) and steelgirders in a 890m section of acentre span.The design conceptof a structural system thatsupports light-weight steelgirders in the centre span – bymaking the side span heavy andrigid with concrete girders andintermediate piers – deliversseveral advantages:• The sectional forces acting on

the girders and towers arereduced.

• Vertical displacements of thegirders are well-controlled.

• Fluctuations in cable tensionare reduced.

The deck is 30.6m wide andcarries four lanes of traffic inboth directions, as well asadditional lanes for bicycles,motorbikes and pedestrians.The two steel towers are 220mhigh and shaped like an inverted“Y” with a slit. This shape waschosen after examining the windresistance, the structuralefficiency and aesthetics. A fullaero-elastic model of a towerwas tested in the wind tunnel to

optimise the shape of thecolumn and its rectangularsection, with notched corners toreduce vortex shedding.

BBR STAY CABLE SYSTEMThe BBR stay cables wereinstalled in a two-plane multi-fanconfiguration. Each tendon –produced and assembled in theworkshop – consisted of a semi-parallel bundle of galvanizedwires, protected by an HDPEjacket filled with an internalcorrosion protection compound.The cable jacket is made ofblack HDPE, which is very

durable in exposed conditions.Its outer surface is dimpled sothat it repels rainwater andbreaks up gusts of wind whichwould cause the cable to vibrate.The high amplitude fatigueresistant anchor sockets arecompletely sealed with nointernal voids. The longesttendons are 460m with adiameter of 170mm.The lengthof the cable is heavily relied onto control the shape.The endsof the strands are fixed bysockets which are sufficientlyresistant to fatigue from bendingvibration, as well as axial force.

TEST & ANALYSISVarious analyses, tests andexperiments were conductedand focused on the characteristicsof long-span structure and theaerodynamic stability of theentire bridge.One of them was large-scaleloading test, at a scale of 1/50,which was conducted to verifythe accuracy of the analysis andconfirm the capacity of thebridge.The results of the modeltest enabled, the ultimate loadingcapacity to be evaluated.Also a large-scale full modelwind tunnel test, at a scale of1/200, was conducted toevaluate the effects oftopography.This showed that themaximum gust responsedisplacement at mid-span waswithin design tolerances.After the bridge had beenstructurally completed, thevertical and horizontal vibrationswere measured by means ofheavy-duty exciters, to confirmthe accuracy of the vibrationcharacteristics applied in thedesign. As a result, the measuredlogarithmic decrement for themain girder basically satisfied thedesign value requirement.Many more technologicaladvances were built into thedesign, testing and erectionworks of the bridge – and all ofthem continue to contributegreatly to the realisation of thedreams of 1000m-class longspan cable stayed bridgesaround the world.

The westernmost route that connectsIkuchijima Island with OmishimaIsland includes Chodai’s design –

Tatara Bridge – a steel-concrete hybrid cablestayed bridge, measuring 1480m in totallength and has an 890m main span.Whenopened on 1st May 1999, this bridge hadthe longest centre span in the world –surpassing its sister bridge, Normandy Bridgein France which has a total length of 2141m,with a 856m centre span.

“ERECTION OFTHE BRIDGE STARTED IN APRIL 1993

ANDTOOK A LITTLE MORETHAN SIXYEARS. NO

TEMPORARY SUPPORTWAS REQUIRED INTHE

WATERWHEN ERECTINGTHE GIRDERS”.

53CONNÆCT

Since the ‘60s, there had been a proposal to builda causeway – in the form of a dam right acrossthe strait of Bahrain and also between Bahrainand Qatar. Nothing came of this, but the idea ofa fixed linkage between the Kingdom of SaudiArabia and Bahrain was never abandoned. In1976, a feasibility study was carried out andincluded hydrographic and topographic surveys,soil investigations, traffic forecasts. This led up to apreliminary design for a 25km long four-lanecauseway consisting of bridges and embankments,as well as about 50km of approach roads in SaudiArabia and Bahrain and a border station.Traffic across the strait between Bahrain andSaudi Arabia was about 90,000 passengers by airand about 80,000 by sea per year and the freightcarried was about 60,000t each year.This freightvolume would have increased tenfold by the timethe Causeway was built and was expected toreach 2.3 million tonnes in 2000. A much largerincrease was foreseen for the passenger traffic –when the Causeway was built the daily traffic wasexpected to be 15,000, but within a year this wasexpected to have increased to 110,000 passengers.

MATERIALS DESIGNFor the bridge superstructure which wasevaluated in both concrete and steel, a single boxgirder cross-section was chosen. For the steelbridge, the span length was 85m and for the

concrete bridge 70m, bothdetermined by economicconsiderations. During the detaileddesign stage in 1977, it was decidedthat the design should be madeonly in steel. Finally, after a designreview, a panel of expertsrecommended that a concretedesign ought also to be drawn upand put out to tender. So the con-sultants embarked upon a design inpre-stressed concrete based on a65m span length bridge with twoseparate box girders in precastelements of full span length oververtical steel piles of large diameter.

CONTRACT AWARDThe international constructioncommunity showed great interestin this project and, after evaluationof 39 responses, a shortlist of 22consortia was invited to tender byJuly 1980.The bids were evaluatedand reviewed by a joint technicalcommittee inWashington. BallastNedam Group NV, in joint venturewith Bandar, was called fornegotiation and they were awardedthe contract awarded in May 1981.

BBR post-tensioning methods were considered tobe one of the most critical elements in terms offacilitating an effective construction scheme, whilstat the same time offering the solution forimpressively stringent conditions in terms ofdurability – and thus, BBR technologies foundtheir way into one of the world’s largest bridgeprojects ever constructed.

STRUCTURAL DESIGNBy the time it was possible to state definitivelywhether the design based on the two mainstructural elements – box girder and pile –satisfied the requirements, the engineering,production planning, manufacturing andconstruction had reached a stage at which itwould no longer be possible to implementchanges without overrun of the overallconstruction period and the overall costs!SubstructureOn the substructure, combining pier and pile tomake one continuous pier-pile element reducedthe degree of freedom available to the designer.Additionally, the single pier chosen forms anextremely slender structure and the one diameterpier-pile allowed for some variation – namely inthe choice of the foundation level of the pile tip.SuperstructureFor the superstructure, a system of cantilever andsuspended girders, lengths of 66 and 34mrespectively, appeared to meet the desired loaddistribution in the superstructure and eliminatedthe undesirable eccentricity of the pier load, whilea slender design and a smooth bridge deck line in

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BAHRAIN CAUSEWAY

The world’s longest bridge

T he provision of post-tensioning work for the Saudi Arabia-Bahrain Causeway,meant that BBR technology was not only applied to one of the world largestbridge projects ever constructed, but was also subjected to impressively stringent

conditions in terms of durability. Dr sc techn Pietro Brenni of BBRVT International Ltdreflects on the construction and technology at the heart of this landmark project.

�

54 CONNÆCT

the final phase were achieved.The suspendedgirder was held by a concrete halving jointbetween the cantilever girder, which was alsoprovided with a halving joint structure for thepurpose. In the overall system assembly, thesuper-structure was formed by a box girderwhich was relatively stiff against torsion and wascarried by four teeth, while the substructureconsisted of a single pier restrained by the(spring) rigidity of the soil.Shipping channelsFinally, the specification required shipping channelsfor all but one of the bridges. According to this,the span of 50m could be maintained for threechannels, raising the elevation by 13m, but a mainshipping channel with 90m free passage wasneeded, requiring the deck elevation to be raisedby more than 24m. At the free passage height of28m, this part of the track had to deviatecompletely from the standard system, whilst alsoconsidering the design constraints imposed byneeding earthquake load and a potential shipcrash load of 5600t to be absorbed by the piers

FOUNDATIONSThe foundation style chosen was based on agravity structure – the piers to support the mainand secondary spans were designed with arectangular cross-section. For the superstructure,the obvious choice was a prefabricated concretesegment solution, built in free cantilever methodand glued together for the bridge with a 150mmain span.The piers were restrained at the foundations andwere of such dimensions that the freely supportedsuperstructure could be extended easily in bothdirections without additional provisions tocompensate for the imbalance moment arisingduring connection of elements to cantilevers.

BBR POST-TENSIONINGAll box girders were designed and executed withboth longitudinal and lateral post-tensioning.Thelongitudinal post-tensioning consisted of BBR

CONA 1906 strand.The numberof cables for the cantilever and thesuspended girder was six and fourper web respectively. Lateral post-tensioning was achieved using BBRV1907mm diameter wire bundles.The engineering and constructionprogramme of some four yearswould necessarily lead to theinstallation of 500 linear metres ofsingle bridge per contract-month,up to a total of 25,000m.

MATERIALS & DURABILITYThe Causeway has to fulfil itsfunction in the severely aggressivesurroundings of the Arabian Gulf.

The environment is characterised by an elevatedsalt content in the sea water, daily average airtemperature fluctuations of approximately 18°Cfrom 9 to 28°C during the coldest months andfrom 23 to 41°C during the hottest months, dailyaverage relative humidity varying from 60% duringthe driest month to 80% during the most humidmonths – and finally, a combination of a rapiddaily temperature changes combined with anextremely drying wind.These very aggressive factors meant a number ofconsequences for the design – particularly detailing– and also for construction. Special measures hadto be taken, both in design and construction, tokeep all crack development – due to shrinkageand temperature stresses – within limits.

Alternative design philosophyAn alternative design, based on the use of large pre-fabricated elementsand on the development of special heavy equipment, was partly derivedfrom the experience with the Zeeland Bridge and the Delta Project inthe Netherlands and partly as a rather obvious consequence of the veryrestricting conditions imposed by the environment.• Soil conditions – bearing stratum <23m, water depth <12m and decklevel with 5m clearance – dictated the choice of a short standard spanof 50m, a box girder of approx 2.5m depth and a weight of 1000t.

• Aggressive water and atmosphere, the very warm climate, theconsiderable total length of the bridge of 25km – combined with thehigh degree of durability needed – favoured the use of pre-fabrication,combined with BBR post-tensioning technology.

• Water conditions, wind conditions, the entire location of the bridgein the sea – and a layout spread over 25km – pointed towards largepre-fabricated elements.

• Four years for design and construction of the overall 25m called formaximum use of – and large scale – pre-fabrication.

• From numerous alternatives for the substructure, it was decided thatstandard longitudinally prestressed prefabricated 3.5m diameter pile-elements, placed in 3.90m diameter boreholes, was the best solution.Each pile would be 40m long and weigh 400t.

1 & 2 Construction of the standard section3 & 4 Typical standard cross-section and PT layout5 & 6 Halving joint between cantilever girder

4

1 2 3

5 6

Source: Hendrick van Tongeren, Saudi Arabia – Bahrain Causeway: Ballast Nedam Group N.V.,Drukkerij Waalwijk b.v.,Waalwijk, 1985, 215pp

55CONNÆCT

By far the main cause of damage to concretestructures along the Arabian Gulf is corrosion ofthe reinforcement, nearly always the result ofpassivation degradation by chloride ions. One ofthe major factors dictating the lifetime of concretein warm sea water is the quality of the rawmaterials, the density and amount of cover of theconcrete, and the extent of wet-curing given to it.The specification for the concrete cover was setto 50mm, following the lines of the fibrecommendation issued by the Commission onConcrete Sea Structures, where the minimumconcrete thickness is set, in general, from 60 to100mm respectively 1.5 times the maximumparticle or rebar size, to be applied for reinforcingsteel and/or post-tensioning cables dependingwhether the exposed zones are completelyunderwater, exposed to tidal and splash, or in awet or dry atmosphere.The amount of concrete cover, combined withthe correct use of post-tensioning, was animportant factor as regards durability.

PREFABRICATIONThe concrete elements for the bridge structurewere pre-fabricated at a yard on the north sideof Umm Nasan island.The location was selectedmainly for nautical reasons – close to a fairway ofsufficient depth.The yard was approximately850m long and 300m wide – and its layout wasdictated by the usage of a 1-gantry crane with alifting capacity of 1400t, span of 80m and aclearance of 20m under the hook.The batching plant was manufactured with acapacity of 2 x 50m3 per hour. All cement wasdelivered by sea, for which purpose an unloadingquay with crane was built. All reinforcement wascut and bent in the yard and made intoprefabricated cages – a total amount of 35,000twas used.In view of the short period available, the timelyand accurate design and manufacture of thevarious pieces of equipment needed for the

chosen construction method wasfundamental to achieving thecompletion date. In late 1982, theequipment for the substructure andthe superstructure had beendelivered.

SUBSTRUCTURECONSTRUCTIONThe construction method for thepiles consisted of two jack-upplatforms used for drillingboreholes for biles in the seabed.Two adjacent positions could bedrilled by using two drilling rigsfrom each platform. A total of 500holes with a borehole diameter of3.75m had to be drilled. Afterinstallation of the casing by cranefrom the jack-up platform, the drillwas lowered and drilling into thehard layers, on which the casingremained supported, could becarried out.

PILE INSTALLATIONThe concrete piles, varying inlength between 20 and 35m andwith a maximum weight of 300tafter assembly, were transported tothe yard’s port by the largetravelling gantry crane. From there,the pile was taken over by a specialpile barge.Once at the site, the pile was liftedup above the casing by a 1000tfloating derrick and lowered intothe borehole. Finally, the spacebetween the pile and the boreholewas filled with grout.The overall average productionamounted to 6.5 piles per week –whilst an average of 4.5 piles perweek had been planned.

INSTALLATION OF SUPERSTRUCTUREThe superstructure elements were transportedwith the Ibis lifting vessel, brought into positionand lifted by means of a gantry placed so that thegirders were at the vessel’s centre of gravity.Theentire installation process could be monitored ona television screen set up in the deck house.The bridge girders were suspended from 4 or 5rods of high quality material mounted on aspreader bar made of steel pipes, suspended fromthe double gantry frame of the lifting vessel by2x2 sheave blocks.The vessel was equipped tocorrect the position of the element with highaccuracy – the elements themselves hadcentering pins, bearings and softwood spacers toaccommodate the positioning and concrete timedependent deformations.

LEVELLING & COMPLETIONAfter six months, shrinkage and creep hadvirtually stopped and the piles had settled, sothe girders could be aligned with a movablescaffolding set up across the bridge andequipped with jacks allowing jacking-up andlevelling of the cantilevered girders.The bridgewas made continuous over stretches of 300m,each of these stretches ending with a grid.The main span superstructure was realised withtraditional prefabricated segments installed bythe free cantilevering method.The hammerheadpiece, measuring 12m, weighed 650t and wasinstalled by floating derrick.The design and the construction of the SaudiArabia-Bahrain Causeway Project, handed overat the end of 1985, was only made possible bythe application of knowledge and resourcesfrom the wide background of experience andleading-edge professionalism offered by allparties involved in the project. BBR isparticularly proud to have contributed with itsproven post-tensioning technology to thesuccessful realisation of one of the world’slargest ever bridge projects. �

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7 View of the main span passages in prefabricated concrete segments 10 Jack-up platforms8 Detail of the BBR CONA Anchorages 11 Erection of the standard element with Ibis lifting vessel9 Prefabrication yard 12 Free cantilevering part to cross the main free passage

10

7 8 9

11 12

56 CONNÆCT

EUROPE

AUSTRIAVORSPANN-TECHNIK GmbH& Co. KGScherenbrandtnerhofstrasse 5A-5021 SalzburgAustria

Tel +43 50 626 2690Fax +43 50 626 2691

www.vorspanntechnik.comvt-austria@vt-gmbh.at

BELGIUM > see Netherlands

BOSNIA / HERZEGOVINA> see Croatia

CROATIABBR Conex Ltd d.d.Kalinovica 3HR-10000 ZagrebCroatia

Tel +385 1 3839 220Fax +385 1 3839 243

www.bbr-conex.hrbbr-conex@bbr-conex.hr

CZECH REPUBLIC > seeAustria

DENMARK > see Norway

FINLAND > see Norway

FRANCEETIC S.A.48, rue Albert JolyF-78 000 VersaillesFrance

Tel +33 1 39 50 11 20Fax +33 1 39 50 11 03

www.etic-international.frcontact@etic-international.fr

GERMANY (NORTH)Spankern GmbHLübecker Strasse 53-63D-39124 MagdeburgGermany

Tel +49 391 726 56 30Fax +49 391 726 56 31

www.spankern.deinfo@spankern.de

GERMANY (SOUTH)VORSPANN-TECHNIK GmbHFürstenrieder Strasse 281D-81377 MünchenGermany

Tel +49 89 71001 200Fax +49 89 71001 201

www.vorspanntechnik.comvt-germany@vt-gmbh.at

HUNGARY > see Austria

IRELAND > see UnitedKingdom

LUXEMBOURG > seeNetherlands

NETHERLANDSSpanstaal B.V.Koningsweg 28NL-3762 EC SoestNetherlands

Post Address:PO Box 386NL-3760 AJ Soest

Tel +31 35 603 80 50Fax +31 35 603 29 02

www.spanstaal.nlinfo@spanstaal.nl

NORWAYKB Spennteknikk ASSiva Industrial EstateN. Strandsveg 19-21Postboks 1213N-2206 KongsvingerNorway

Tel +47 62 81 00 30Fax +47 62 81 00 55

www.spennteknikk.nospennteknikk@spennteknikk.no

POLANDBBR Polska Sp. z o. o.ul. Marywilska 38/40PL-03-228WarszawaPoland

Tel +48 22 811 50 53Fax +48 22 614 57 60 (ext.108)

www.bbr.plbbrpolska@bbr.pl

POLAND (SOUTH)BBR Polska Sp. z o. o.ul.Tanogorska 214aPL-44-102 GliwicePoland

Tel +48 32 33 02 410Fax +48 32 33 02 411

www.bbr.plbbrpolska@bbr.pl

PORTUGAL > see Spain

ROMANIA > see Spain

SERBIA / MONTENEGRO> see Croatia

SLOVENIA> see Croatia

SPAINBBR Pretensadosy Técnicas Especiales, S.L.Antigua Carretera N-III,km. 31,150E-28500 Arganda del Rey,MadridSpain

Tel +34 91 876 09 00Fax +34 91 876 09 01

www.bbrpte.combbrpte@bbrpte.com

SWEDENSpännteknik ABBox 158SE-671 24 ArvikaSweden

Tel +46 570 126 60Fax +46 570 109 50

www.spannteknik.seinfo@spannteknik.se

UNITED KINGDOMStructural Systems (UK) Ltd12 Collett WayGreatWestern Industrial EstateSouthallMiddlesexUB2 4SEUnited Kingdom

Tel +44 20 8843 6500Fax +44 20 8843 6509

www.structuralsystemsuk.cominfo@structuralsystemsuk.com

ASIA PACIFIC

AUSTRALIA (NORTH)Structural Systems (Northern)Pty Ltd20 Hilly StreetMortlakeNew SouthWales 2137Australia

Tel +61 2 9743 2111Fax +61 2 9743 2099

www.structuralsystems.com.auinfo@northern.structural.com.au

AUSTRALIA (SOUTH)Structural Systems (Southern)Pty LtdPO Box 1303112 Munro StreetSouth MelbourneVictoria 3205Australia

Tel +61 3 9646 7622Fax +61 3 9646 7133

www.structuralsystems.com.aussl@structural.com.au

AUSTRALIA (WEST)Structural Systems (Western)Pty LtdPO Box 6092 - Hilton24 Hines RoadO’ConnorWestern Australia 6163Australia

Tel +61 8 9331 4500Fax +61 8 9331 4511

www.structuralsystems.com.austructural@wa.structural.com.au

BANGLADESH > seeSingapore

FIJI > see New Zealand

INDIABBR (India) Pvt LtdNo.318, I & II Floor,15th Cross, 6th Main,SadashivanagarBangalore - 560 080India

Tel +91 80 4025 0000Fax +91 80 4025 0001

www.bbrindia.combbrindia@vsnl.in

INDONESIA > see Singapore

BBRWorldwide Directory

57CONNÆCT

JAPANJapan BBR Bureauc/o P.S. Mitsubishi ConstructionCo. LtdHarumi Center Bldg. 3F2-5-24, Chuo-kuTokyoJapan

Tel + 81 3 6385 8021Fax + 81 3 3536 6937

mail-01@bbr.gr.jp

MALAYSIABBR Construction Systems (M)Sdn Bhd32, Jalan PJS 11/20Sunway Technology ParkBandar Sunway46150 Subang JayaSelangor Darul EhsanMalaysia

Tel +60 3 5636 3270Fax +60 3 5636 3285

www.bbr.com.mybbrm@bbr.com.my

NEW ZEALAND(AUCKLAND)BBR Contech6 Neil Park Drive, East TamakiPO Box 51-391PakurangaAucklandNew Zealand

Tel +64 9 274 9259Fax +64 9 274 5258

www.contech.co.nzakl@contech.co.nz

NEW ZEALAND(CHRISTCHURCH)BBR Contech7A Birmingham DriveMiddletonPO Box 8939RiccartonChristchurchNew Zealand

Tel +64 3 339 0426Fax +64 3 339 0526

www.contech.co.nzchc@contech.co.nz

NEW ZEALAND(WELLINGTON)BBR Contech38Waione Street, PetonePO Box 30-854Lower HuttWellingtonNew Zealand

Tel +64 4 569 1167Fax +64 4 569 4269

www.contech.co.nzwgn@contech.co.nz

PHILIPPINESBBR Philippines CorporationSuite 502, 7 East Capitol BuildingNo.7 East Capitol DriveBarangay KapitolyoPasig City 1603Metro ManilaPhilippines

Tel +63 2 638 7261Fax +63 2 638 7260

bbr_phils@pacific.net.ph

SINGAPOREBBR Construction SystemsPte LtdBBR Building50 Changi South Street 1Singapore 486126Republic of Singapore

Tel + 65 6546 2280Fax + 65 6546 2268

www.bbr.com.sgenquiry@bbr.com.sg

SRI LANKA > see Singapore

THAILANDSiam-BBR Co Ltd942/137.1 5th FloorCharn Issara TowerRama 4 RoadKwaeng Suriwongse, Bangrak10500 BangkokThailand

Tel +66 2 237 6164-6Fax +66 2 237 6167

www.bbr.com.sgenquiry@bbr.com.sg

MIDDLE EAST

BAHRAIN > see United ArabEmirates

IRAQSpezialized Prestressing CoKarrada, Dist. 901, St. 1, Bldg. 16Office No. 10BaghdadIraq

Tel +964 1 718 6333Fax +964 1 718 1385

www.spc-iraq.comco_spc@yahoo.com

JORDANMarwan Kurdi & PartnersCo. LtdPO Box 506Amman 11821Jordan

Tel +962 6 581 9489Fax +962 6 581 9488

www.mkurdi.comali@mkurdi.com

OMAN > see United ArabEmirates

QATAR > see United ArabEmirates

KINGDOM OFSAUDI ARABIAHUTA–HEGERFELDSAUDIA LTDBBR Prestressing DivisionPrince Sultan St. Lotus BuildingPO Box 1830Jeddah 21441Kingdom of Saudi Arabia

Tel +966 2 662 3205Fax +966 2 683 1838

www.huta.com.sabbr@huta.com.sa

SYRIA > see Jordan

UNITEDARAB EMIRATESNASA (BBR) StructuralSystems LLCSarah Building, GarhoudDubaiUnited Arab Emirates

Tel +97 1 4282 8595Fax +97 1 4282 8386

www.bbrstructuralsystems.combbr@bbrstructuralsystems.com

AMERICAS

CANADACanadian bbr Inc.PO Box 37AgincourtOntario M1V 4V4Canada

Tel +1 416 291 1618Fax +1 416 291 9960

mducommun@bbrcanada.com BBR

DIRE

CTOR

Y

HEADQUARTERSBBR VT International LtdBahnstrasse 23CH-8603 Schwerzenbach (ZH)Switzerland

Tel +41 44 806 80 60Fax +41 44 806 80 50

www.bbrnetwork.cominfo@bbrnetwork.com

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