Concrete Off ers for the Period of Economic Recovery

Final Programme

Abstracts

www.cbsbeton.eu/ccc2014

LIBEREC 2014

1–2 October 2014

Liberec Regional Gallery

Masarykova 723/14, 460 01 Liberec

Czech Republic

50°46‘25.756“N, 15°4‘4.069“E

Host CCC Association

Czech Concrete Society

Česká betonářská společnost ČSSI

www.cbsbeton.eu

LIBEREC 2014

CCC 2014

Final Programme

Abstracts

Central European Congress on Concrete Engineering

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C C C M E M B E R C O U N T R I E S

The 10th Central European Congress on Concrete Engineering

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CONGRESS PROGRAMME AT A GLANCE

TIME

1 OCTOBER 2014

MAIN HALLGround

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08:00–09:00 Registration

09:00–09:15 OPENING CEREMONY

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09:15–10:30SESSION W1:

KEYNOTE SPEECHES

10:30–11:00 Morning coff ee break

11:00–11:40 SESSION W2: KEYNOTE SPEECHES

11:40–12:40

NEW PROJECTS IN THE CENTRAL EUROPEAN INFRASTRUCTURE NETWORK

CONCERETE STRUCTURES CORRESPONDING TO PRESENT-DAY ECONOMIC CONDITIONS

12:40–14:00 Lunch break

14:00–15:45SESSION W3: CONCERETE STRUCTURES

CORRESPONDING TO PRESENT-DAY ECONOMIC CONDITIONS

15:45–16:05 Afternoon break

16:05–18:00SESSION W4: CONCERETE STRUCTURES

CORRESPONDING TO PRESENT-DAY ECONOMIC CONDITIONS

19:30–20:00 TRANSPORT TO JEŠTĚD

20:00–23:00 SOCIAL EVENING

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2 OCTOBER 2014

MAIN HALLGround

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09:00–11:00

SESSION T1: ADVANCED STRUCTURAL SYSTEMS AND

TECHNOLOGIES IN BUILDINGS, INDUSTRIAL AND WATER CONSTRUCTIONS

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11:00–11:30 Morning buff et break

11:30–13:15

SESSION T2:ADVANCED STRUCTURAL SYSTEMS

AND TECHNOLOGIES IN BUILDINGS, INDUSTRIAL AND WATER CONSTRUCTIONS

13:15–13:30 CONGRESS CLOSING

No. Exhibitor Facility1 IDEA RS s.r.o. Exhibition desk2 Červenka Consulting s. r. o. Exhibition desk3 VALBEK-EU, a. s. Exhibition desk4 NOVÁK & PARTNER, s. r. o. Exhibition desk

5Wilhelm Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG

Journal

CCC Corner – Founding member countries

PLAN OF THE CONGRESS AREAAND EXHIBITION

Lunch and refreshment

CCC corner

Gallery1st fl oor

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Pool HallTechnical

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Poster sessions

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HOST CCC ASSOCIATION

The 10th Central European Congress on  Concrete Engineering LIBEREC 2014 is hosted by the Czech Concrete Society (CBS) (Czech national member group of fi b)

SCIENTIFIC COMMITTEEJan L. VÍTEK, Chairman (Czech Republic)György L. BALÁZS (Hungary)Konrad BERGMEISTER (Austria)Jan BILISZCZUK (Poland)Dubravka BJEGOVIĆ (Croatia)Jiří KOLÍSKO (Czech Republic)Johann KOLLEGGER (Austria)Katalin KOPECSKÓ (Hungary)Kálmán KORIS (Hungary)Renata KOTYNIA (Poland)Peter KREMNITZER (Austria)Jure RADIĆ (Croatia)Marek SALAMAK (Poland)Zlatko ŠAVOR (Croatia)Vlastimil ŠRŮMA (Czech Republic)

ORGANIZING COMMITTEEMichal ŠTEVULA, Chairman (Czech Republic)Pawel HAWRYSZKÓW (Poland)Petra JOHOVÁ (Czech Republic)Marija KUŠTER (Croatia)Éva LUBLÓY (Hungary)Michael PAUSER (Austria)Jiří VÍCH (Czech Republic)

CONGRESS SECRETARIATCzech Concrete SocietySamcova 1110 00 Prague 1Czech RepublicTel.: +420 222 316 195,+ 420 605 325 366, + 420 775 124 100 Fax: +420 222 311 261Email: ccc2014@cbsbeton.euwww.cbsbeton.eu/ccc2014

CONGRESS PROGRAMME

WEDNESDAY, 1 OCTOBER 2014

09:00 – 9:15 OPENING CEREMONYOpening of the CongressJiří Kolísko (Czech Concrete Society, Czech Republic)Speech of welcome on behalf of the town of LiberecMichal Števula (Czech Concrete Society, Czech Republic)Invitation to the 11th CCC Congress in Hainburg, Austria 2015Michael Pauser (Austrian Society for Construction Technology (OVB))

09:15 – 10:30 SESSION W1: KEYNOTE SPEECHESChairmen: Jan L. Vítek (Czech Republic), Michael Pauser (Austria)Reconstruction of the Bath in LiberecJiří Buček (Sial architekti a inženýři, spol. s r. o., Czech Republic)Port DUNAVECSE practical reuse and extension of former auxiliary structures, (1571 + 890 – 1572 + 250 km section on the left side of river Danube) Gábor Alajos Molnár, Balázs Karkiss (KÉSZ Ltd., Hungary)Realtime monitoring of the compressive strength development of concreteAlexander Reinisch (Doka Industrie GmbH, Austria)Dynamic behaviour of footbridges with concrete decksPaweł Hawryszków (Wrocław University of Technology, Poland)

10:30 – 11:00 Coff ee break

11:00 – 12:30 SESSION W2: KEYNOTE SPEECHESChairmen: Jiří Kolísko (Czech Republic), György L. Balázs (Hungary)Beauty as a form of structural infl uenceJure Radič, Marija Kušter Marić, Jelena Bleiziff er (University of Zagreb – Faculty of Civil Engineering, Institute IGH, Croatia) Cable-stayed footbridge with segmental UHPC deckMilan Kalný, Václav Kvasnička, Jan Komanec, Robert Brož, Petr Koukolík, Jan L. Vítek (Pontex s. r. o., Metrostav a. s., Czech Republic)

SESSION W2: NEW PROJECTS IN THE CENTRAL EUROPEAN INFRASTRUCTURE NETWORK Prestressed concrete cantilever beam bridges in PolandRobert Toczkiewicz, Jan Biliszczuk, Hanna Onysyk (Research & Design Offi ce Mosty-Wrocław, Poland)New Troja Bridge in Prague – structure analysis during construction process Lukáš Vráblík (Novak & Partner, s. r. o., Czech Republic)

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SESSION W2: CONCERETE STRUCTURES CORRESPONDING TO PRESENT-DAY ECONOMIC CONDITIONS

First post-tensioned concrete bridges in PolandJerzy Onysyk, Jan Biliszczuk (Wrocław University of Technology, Poland)

12:30 – 14:00 Lunch break

14:00 – 15:35 SESSION W3: CONCERETE STRUCTURES CORRESPONDING TO PRESENT-DAY ECONOMIC CONDITIONS

Chairmen: Alena Kohoutková (Czech Republic), Jure Radič (Croatia)

Shaping and material characteristics of motorway viaducts built in the1930s Jerzy Onysyk, Wojciech Barcik (Wrocław University of Technology, Poland)

Challenges in the assessment of existing concrete bridgesRoman Lenner, Manfred Keuser, Thomas Braml (Universität der Bundeswehr, Germany)

Recent tasks and requirements to computer analysis of concrete structuresRadomír Pukl, Tereza Sajdlová, Jitka Mikolášková, Dobromil Pryl, Petr Kabele, Petr Havlásek (Červenka Consulting s. r. o., Czech Republic)

Modelling of Sentab type high pressure water pipes after deteriorationGyörgy L. Balázs, Olivér Czoboly, Éva Lublóy, Péter Zimmer (Budapest University of Technology and Economics, Hungary)

Assessment of durability of a bridge on Polish-Czech border constructed with the use of an incremental launching technologyMarek Salamak, Andrzej Radziecki, Stefan Pradelok (Silesian University of Technology, Poland)

Improved method of 3dD analysis of bridges with changes of structural systems aff ected by rheological phenomenaLukáš Kadlec, Vladimír Křístek (Technical University of Prague, Czech Republic)

15:45 – 16:05 Coff ee break

CONGRESS PROGRAMME

WEDNESDAY, 1 OCTOBER 2014

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CONGRESS PROGRAMME

WEDNESDAY, 1 OCTOBER 2014

16:05 – 18:00 SESSION W4: CONCERETE STRUCTURES CORRESPONDING TO PRESENT-DAY ECONOMIC CONDITIONS

Chairmen: Milan Kalný (Czech Republic), Paweł Hawryszkow (Poland)

Framework for life cycle assessment of engineering structuresHirut Grossberger, Konrad Bergmeister, Alfred Strauss(University of Natural Resources and Life Sciences, Austria)

Searching for environmentally friendly alkali-activated concrete for building elementsVlastimil Bílek, Vladimíra Tomalová, Libor Topolář, Luboš Pazdera, Libor Židek (ŽPSV a. s. Czech Republic)

Sustainability in tunneling – CO2 –balances derived from investigations concerning the brenner basis tunnel projectManfred Keuser, Konrad Bergmeister, Juliane Otto, Hannes Lückmann (Universität der Bundeswehr, Germany, Universität für Bodenkultur, Austria)

Rehabilitation of the main collector sewer in BudapestKálmán Koris, István Bódi (Budapest University of Technology and Economics, Hungary)

Applied methodology for calculating the Structural safety of tunnel linings exposed to fi reRuben Van Coile, Robby Caspeele, Alfred Strauss , Konrad Bergmeister,(University of Natural Resources and Life Sciences, Institute for Structural Engineering, Austria, University Ghent, Belgium)

Synthetic and steel fi bres in prestressed, precast long span beamsGábor Kovács, Károly Péter Juhász (ASA Építőipari Kft., Hungary)

Long-term deformation of SRC columnGyeong-Hee AN, Jin-Keun KIM (KAIST, Republic of Korea)

19:30 – 20:00 Transport to Ještěd

20:00 – 23:00 Social Evening – Ještěd, Liberec

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09:00 – 11:00 SESSION T1: ADVANCED STRUCTURAL SYSTEMS AND TECHNOLOGIES IN BUILDINGS, INDUSTRIAL AND WATER CONSTRUCTIONS

Chairmen: Radomír Pukl (Czech Republic), Marek Salamak (Poland)

Three or four-point bending tests for identifi cation of material characteristics of fi ber reinforced concreteMartin Kovář, Marek Foglar, Vladimír Křístek (Technical University of Prague, Czech Republic)

Strengthening of structures by TRC as a contribution to resource conservation using the example of columnsRegine Ortlepp (Leibniz Institute of Ecological Urban and Regional Development, Germany)

Eurocode design of composite concrete beamsJaroslav Navrátil (IDEA RS, s. r. o., Czech Republic)

Collection of experimental concrete test data for model calibration and validation + Comparison of concrete models based on a large collection of testsRoman Wendner, Jan Vorel, Marco Marcon, Gianluca Cusatis (Christian Doppler Laboratory LiCRoFast, Austria)

Shrinkage strain in thick concrete elementsJan L. Vítek, David Čítek, Jiří Kolísko (Metrostav a. s., Czech Republic)

Measurement of shrinkage on concrete specimensThomas Zimmermann, Alfred Strauss, David Lehký, Drahomír Novák(University of Natural Resources and Life Sciences, Institute for Structural Engineering, Austria, Brno University of Technology, Czech Republic, Vienna University of Technology, Austria)

Nonlinear analysis of Troja Bridge in PragueJan Červenka, Vladimír Červenka, Jan L. Vítek (Červenka Consulting s. r. o., Metrostav a. s., Czech Republic)

11:00 – 11:30 Morning buff et break

CONGRESS PROGRAMME

THURSDAY, 2 OCTOBER 2014

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CONGRESS PROGRAMME

THURSDAY, 2 OCTOBER 2014

11:30 – 13:15 SESSION T2: ADVANCED STRUCTURAL SYSTEMS AND TECHNOLOGIES IN BUILDINGS, INDUSTRIAL AND WATER CONSTRUCTIONS

Chairmen: Lukáš Vráblík (Czech Republic), Michal Števula (Czech Republic)

Precast sandwich panel – innovative way of construction Marina Alagušić, Ivana Banjad Pečur, Ivana Carević, Bojan Milovanović(Faculty of Civil Engineering, University of Zagreb, Croatia)

Destructive tests of pretensioned UHPC beams Jan Tichý, Jiří Kolísko, Milan Kalný (Skanska a. s., Pontex s. r. o., Czech Republic)

Shear cracks in the thin-wall pre-stressed element – numerical and experimental analysisJan Hamouz, Lukáš Vráblík (Technical University of Prague, Czech Republic)

First application of prestressed CFRP strips with gradient anchorage in strengthening post-tensioned concrete bridge in Szczercowska WieśRenata Kotynia, Julien Michels, Michal Staskiewicz, Christoph Czaderski, Masoud Motavalli (Lodz University of Technology, Poland)

Shear-friction behavior of traditional and self-consolidating concrete in reinforced precast elements with in-situ concrete overlayFlorian Junker, Klaus Holschemacher, Torsten Mueller (Leipzig University of Applied Sciences, Germany)

What’s new in creep of concrete in fi b model code 2010?Janusz Hołowaty (West Pomeranian University of Technology, Szczecin, Poland)

Reconstruction and strengthening of long viaduct made of prestressed lightweight concreteMarek Salamak, Bogusław Markocki (Silesian University of Technology, Poland)

13:15 – 13:30 Closing of the Congress

Bus to the Ještěd peak

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Social Evening at the JeštědWednesday, 1 October 2014, 20:00 – 23:00

The Congress dinner will be held on Wednesday, 1 October 2014 in an enchanting evening environment of the Ještěd hotel. The unusual structure – the Tower on the peak of Ještěd mountain near the city of Liberec, is both a  television tower and a hotel. The registered participants will be transported by bus and by a cable car to the Tower. A short lecture on this architectural monument will be presented after arrival. The organisers believe that the participants will enjoy the Tower and the complete evening program in the attractive atmosphere of the Ještěd peak.

The bus will leave the Regional Gallery in Liberec, Vítězná street (around the corner - see picture below) at 19:30. The bus will be marked by poster “CBS” and it will go to the lower station of the cable car to the peak Jested. The bus will wait next to the cable car station after the evening termination, as from 23:00. It will return you to the Regional Gallery in Liberec.Please remember the weather could be unstable and relatively cold as well during the evening. An umbrella may come in handy.

SOCIAL PROGRAMME

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Since the number of submitted abstracts has been greater than the places available for oral presentation, the Congress off ers the fl oor for poster presentations. There are together 10 exhibited posters in the Congress Poster Session. All of them are published in full extent in the Congress Proceedings.

LIST OF TECHNICAL POSTERS

P01

Experimental and theoretical fl ow of the forces in deep beams with cantileverKrystyna Nagrodzka-Godycka, Anna Knut, Kamila Zmuda-Baszczyn (Poland)

P02Experimental study on concrete with high modulus of elasticity for tall buildings Tianyuan Fan, Zongjin Li, Christopher Leung, Herbert Zheng (China)

P03Indirect determination of support reactions in concrete bridge elementsMarek Salamak, Piotr Klikowicz (Poland)

P04Optimization system Moravamont for construction in seismic conditionsŽivko P. Cuckić, Vesna Cuckic (Serbia)

P05Tensile characteristics and strength classes of FRCVáclav Ráček, Jan Vodička, Jiří Krátký (Czech Republic)

P06

Study on ultimate strength and failure mechanism of RC members due to interaction between torsion and other sectional forceRyohei Yanagida, Katsuki Kondo , Takahisa Okamoto (Japan)

P07Down the drain: Does surplus pour material have potential?Amy L. Bauman (USA)

P08Contenporary models for shrinkage in cement concreteJanusz Hołowaty (Poland)

P09Assessment of span precamber in prestressed concrete fl yover constructed on movable scaff oldingJan Biliszczuk, Robert Toczkiewicz (Poland)

P10Flexural stiff ness analysis of RC beams strengthened with FRP sheetsTomislav Brozović, Tomislav Kišiček, Goran Puž (Croatia)

POSTER SESSION

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SESSION W1 9:15–10:30

PORT DUNAVECSEPRACTICAL REUSE AND EXTENSION OF FORMER AUXILIARY STRUCTURES,(1571+890 – 1572+250 KM SECTION ON THE LEFT SIDE OF RIVER DANUBE) Gábor Alajos Molnár, Balázs Karkiss

Port DUNAVECSE is a heavy barge transferring harbour on Danube, being located section 1571+890 – 1572+250 km on the left side of the river. The main function of the structure is transferring heavy products and grain material from the barges to the land back and force. That is why the uniform load bearing capacity of the structure is 10k N/m2, and the point load bearing capacity is three pieces 60 tones crane and/or lorry. The structure has even more point load bearing capacity with special criterions.The foundation on both ends of the harbour is a high diameter pile group with common concrete head block on the top of them. Both pile groups contain four pieces 1500  mm diameter SOIL-MEC piles, and an 1800  mm high cast in situ concrete head block. The historical function of these pile groups were the auxiliary assembly structures of bridge Pentele. In order not to leave them to decay, we reused them for being part of a fi nal structure.The upper structure consist of two main beams, seven purlins, more than 100 m side beams, 86 pieces horizontal solid slab, 23 pieces vertical inbuilding moulding panels and high amount of cubic meter cast in situ concrete. The main beams consist of two parts; the fi rst is the more than 50 tones 80 pieces Y1860S7-12.5 strands prestressed precast beam, the second is the cast in situ upper part using the 23 pieces inbuilding moulding panels. The average weight of the seven non-prestressed precast purlins is 20 tones containing 1.2 tones reinforcement.Port DUNAVECSE has been already in use, and play important connection link between water and road transportation. The harbour was designed and assembled by KÉSZ Ltd.

SESSION W1 9:15–10:30

REALTIME MONITORING OF COMPRESSIVE-STRENGTH-DEVELOPMENT OF CONCRETEAlexander Reinisch, Wilko van der Meer

One of the future trends in building is to making processes more and more effi cient to save money and to archive a high level quality result.For optimising a process it is essential to measure the relevant parameters. Real-

ABSTRACTS

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time concrete strength monitoring is an effi cient instrument for optimising the building process, because the compressive strength development of concrete is one of the most relevant parameters in the construction process.The innovative real-time concrete monitoring system is a  combination of the state-of-the-art maturity method by de Vree and modern mobile communications technology.

SESSION W1 9:15–10:30

DYNAMIC BEHAVIOUR OF FOOTBRIDGES WITH CONCRETE DECKSPaweł Hawryszków

The paper concerns problems of the dynamic behaviour of footbridges. Results of dynamic investigations of footbridges equipped with concrete decks are presented in this paper and compared with dynamic responses of footbridges made of others structural materials.

SESSION W2 11:00–12:30

BEAUTY AS A FORM OF STRUCTURAL INFLUENCEJure Radić, Marija Kušter Marić, Jelena Bleiziff er

Bridges are dominant in space not only by their large dimensions, but also by number of  their users and service life; therefore, it is necessary to design not only durable and economical bridges, but also aesthetically pleasant structures. Several case studies of  recently built or designed bridges in Croatia, presented in the paper, confi rm that careful selection of structure form according to traffi c requirements and environment specifi cities can result in beautiful landmarks. Political decisions as well as environmental restriction and traffi c requirements can signifi cantly aff ect the development of the bridge design project. However, bridge engineering in itself is a key discipline in the process and if holistic approach to bridge design is used, the result is structure, which not only meets all requirements and constraints, but it is also aesthetically pleasant bridge well integrated into the natural environment, regardless of the selected bearing system type. This paper presents how various requirements and restrictions infl uence on bridge load-bearing system selection. Moreover, attractiveness of bridge type depends signifi cantly on context sensitive design, as it is shown in the paper.

ABSTRACTS

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SESSION W2 11:00–12:30

CABLE-STAYED FOOTBRIDGE WITH SEGMENTAL UHPC DECKMilan Kalný, Václav Kvasnička, Jan Komanec, Robert Brož, Petr Koukolík, Jan L. Vítek

Ongoing research and development of ultra-high performance concrete (UHPC) in the Czech Republic has been utilized in design and implementation of light-weight segmental deck of the cable-stayed footbridge over the Labe River in Celakovice with main span of  156  m. Detailing, design issues, construction method and effi ciency of using UHPC on  this large span lightweight bridge is described in the paper. The superstructure of the Celakovice footbridge was completed in the December 2013 and the bridge was opened for  the public in April 2014. Main advantages of this project is not only low maintenance and reasonable life cycle cost but also favourable initial cost which was achieved by the contractor Metrostav a.  s. due to combination of high-strength modern materials.

SESSION W2 11:00–12:30

PRESTRESSED CONCRETE CANTILEVER BEAM BRIDGES IN POLANDJan Biliszczuk, Hanna Onysyk, Robert Toczkiewicz

The transportation network in Poland has been intensively developed and modernized over the last years. Approximately 300 new road bridges are built annually. Among new structures, many consist of large spans exceeding 100 m, particularly when crossing wide rivers is inevitable. Cantilever concreting is primary method in case of erecting concrete beam structures. Origins of the applications of cantilever method are dated on 1960’s and within last 20 years has become common and for the time being is successfully used in construction of concrete bridges. In the paper, the largest post-tensioned concrete bridge structures in Poland erected by the use of cantilever concreting method are described. These are:❚ bridge along the A1 motorway over the Vistula River with a  span of 180  m

(the longest cantilevered span in Poland);❚ skewed bridge over the Oder River in Kędzierzyn-Koźle with a span of 140 m;❚ bridge over the Oder River in Brzeg Dolny with a span of 140 m;❚ bridge over the Bug River with span of 136 m.Structural confi guration and construction technology of described bridges are presented.

ABSTRACTS

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SESSION W2 11:00–12:30

NEW TROJA BRIDGE IN PRAGUE – STRUCTURE ANALYSIS DURING CONSTRUCTION PROCESSLukáš Vráblík, Jan Mukařovský, Jakub Růžička, Milan Šístek

The structure of the new Troja Bridge crosses the Vltava River on northern part of city centre. The bridge has two spans – the main span is crossing the river and is 200,4 m long and the side span is 40,4 m long. The main span is crossed over by steel network arch, which is extremely fl at (rise/span ratio is 1/10), and by the suspended concrete deck with tie. The side span is single span completely in situ cast prestressed concrete structure. Final structure behaviour and construction process of the bridge is very complex and diffi cult. It  was necessary to use lots of computational models for simulation and prediction of structure behaviour. The results from mathematical simulation were continuously compared with measurement results and computational models were continuously updated. The construction process is now almost fi nished.

SESSION W2 11:00–12:30

FIRST POST-TENSIONED CONCRETE BRIDGES IN POLANDJerzy Onysyk, Jan Biliszczuk

The paper presents structures of two densely ribbed bridges, externally and internally prestressed, built in the province of Lower Silesia in the 1950s. The pioneering structure containing external prestressing was designed in the Bridge Department at Wrocław University of Technology. Structural details of the form of the concrete spans and of the prestressing are introduced. The original design documentation has been preserved. The  paper provides assessment of the applied materials as well as of the static and structural solutions in the light of the sixty year long operation.

ABSTRACTS

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SESSION W3 14:00–15:35

SHAPING AND MATERIAL CHARACTERISTICS OF MOTORWAY VIADUCTS BUILT IN THE 1930SJerzy Onysyk, Wojciech Barcik

In the 1930s, numerous reinforced concrete viaducts with various static and structural systems were built along the A4 motorway between the cities of Wrocław and Legnica. First conclusions about these structures were drawn already after the spans had been lifted a  few dozens centimeters during the fi rst modernization of this section of the A4 motorway, in 1993÷1994, in order to improve the vertical clearance. Further conclusions can be drawn based on damage to one of the viaducts over the A4 motorway after following years of supervision. The destructive eff ect of precipitation water and humidity carried by the passing vehicles led to a threat of collapse. The paper presents the infl uence of the shape and of the quality of concrete on the durability of the piers in the context of the historical reinforced concrete. The following question is raised: are these structures intended for demolition despite their historic value?

SESSION W3 14:00–15:35

CHALLENGES IN THE ASSESSMENT OF EXISTING CONCRETE BRIDGESRoman Lenner, Manfred Keuser, Thomas Braml

It is well known that the ageing transportation infrastructure requires some attention. Many existing bridges exhibit signs of deterioration due to the increased traffi c intensity and due to ageing and their calculated performance according to the most current design codes is often considered as inadequate. The challenge is to allocate funds for maintaining the operational capacity of the existing networks. From the economic point of view, it makes sense to assess the load carrying capacity and the loading level in larger detail before an expensive and maybe unnecessary repair or replacement take place. Advanced methods of assessment often off er a solution. Reliability analysis and partial factor adjustment within the semi-probabilistic safety concept are particularly attractive for the re-calculation of resistance, the assessment of load eff ects and the evaluation of structural safety. The aim of this paper is to concentrate on particular aspects of resistance and load eff ect. This includes damage to concrete and reinforcement. Some of the traffi c stochastic models are studied in order to account for restricted better defi ned loading. The use of methods tailored to existing concrete bridges and better defi ned loading may often lead to a more economical solution and to an extended service life while providing the necessary structural safety.

ABSTRACTS

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SESSION W3 14:00–15:35

RECENT TASKS AND REQUIREMENTS TO COMPUTER ANALYSIS OF CONCRETE STRUCTURESRadomír Pukl, Tereza Sajdlová, Jitka Mikolášková, Dobromil Pryl, Petr Kabele, Petr Havlásek

Selected applications of nonlinear FEM analysis of existing and designed concrete structures are presented. Optimal solution strategies for selected civil engineering problems are proposed. Development of non-linear material models for non-traditional materials (fi bre reinforced concrete, ultra high performance concrete, advanced cementitious composites) and actions (fatigue) and their application to computer simulation of structures are discussed. Methods for an effi cient design of modern engineering structures based on the nonlinear computer analysis are described.

SESSION W3 14:00–15:35

MODELLING OF SENTAB TYPE HIGH PRESSURE WATER PIPES AFTER DETERIORATIONGyörgy L. Balázs, Olivér Attila Czoboly, Éva Lublóy, Péter Zimmer

In Hungary the production and application of the Sentab water pipes started in 1969. These pipes have a  very important part in the water supply system of Budapest and numerous other places. Overall 360  km Sentab type water pipes were installed in Hungary. In our research we analysed the production technology of the water pipes, to locate the main possible causes of the deterioration. We carried out non-destructive tests on uncovered Sentab water pipes that are still in use. We also carried out destructive tests on Sentab pipes that are out of use. In our research we analysed what kind of processes are the main causes of the deteriorations.We carried out fi nite element modelling of the Sentab type water pipe in order to determine the load bearing capacity of the pipe, in case some of threads of the spiral tendon were damaged. So we can estimate the residual load bearing capacity from the visual observation of the rust spot at the concrete surface.

ABSTRACTS

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SESSION W3 14:00–15:35

ASSESSMENT OF DURABILITY OF A BRIDGE ON POLISH-CZECH BORDER CONSTRUCTED WITH THE USE OF AN INCREMENTAL LAUNCHING TECHNOLOGYMarek Salamak, Andrzej Radziecki, Stefan Pradelok

A bridge going through the Olse Valley at the border of Poland and Czech Republic in Cieszyn and Český Těšín is one of the larger and older prestressed structures in Poland. Due to its size (700 m), the geometric complexity (vertical and horizontal arch) and construction technology (incremental launching) is observed with a special care since its commissioning. At the end of 2013, after more than twenty years of operation, additional measurements and detailed examinations of the structure were carried out. This paper presents the conclusions from those actions and experiences from the conducted so far observations. They relate mainly to changes in the geometry of the structure and the condition of the superstructure and accessories.

SESSION W3 14:00–15:35

IMPROVED METHOD OF 3D ANALYSIS OF BRIDGES WITH CHANGES OF STRUCTURAL SYSTEMS AFFECTED BY RHEOLOGICAL PHENOMENALukáš Kadlec, Vladimír Křístek, Jan L. Vítek

Due to increase of requirements on accuracy of structural analyses, practically applicable computational tools for reliable determination of the real structural performance of bridges are needed. A  method is proposed for the true full 3D analysis which can be applied to achieve the real spatial behaviour of concrete bridge structures taking into account rheological phenomena and changes of structural systems. Particularly, the eff ects of shear lag, shear performance of webs of box girders, warping torsion, warping of cross-sections, distortional eff ects, state of stresses in the singular regions, the real prestress loss, etc., can be correctly determined. The method combines conventional approaches (based on the elementary beamtype assumptions) for calculating the time development of the internal forces due to rheological phenomena and changes in the structural system during construction and routine commercial FEM software intended for calculating spatial shell structures. The method is capable to give the true 3D prediction of structure behaviour by using only commercially available software. The primary advantage of the proposed method is its ease of application which allows the true 3D performance to be determined from simple calculations.

ABSTRACTS

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SESSION W4 16:05–18:00

FRAMWORK FOR LIFECYCLE ASSESSMENT OF ENGINEERING STRUCTURESHirut Grossberger, Konrad Bergmeister, Alfred Strauss

The aim of this paper is to present a framework for time-dependent performance indicators of concrete structures and prediction methods. The lifecycle assessment framework incorporates establishment of effi cient and practical procedures for assessment the future deterioration and already performed and planned actions of inspection and maintenance over lifecycle cost of structures. For practical applicability of the lifecycle assessment framework; a case study was performed on one Austrian railway bridge.

SESSION W4 16:05–18:00

SEARCHING FOR ENVIRONMENTALLY FRIENDLY ALKALI-ACTIVATED CONCRETE FOR BUILDING ELEMENTSVlastimil Bílek, Vladimíra Tomalová, Libor Topolář, Luboš Pazdera, Libor Žídek

Alkali activated concretes (AACs) are considered to be an alternative to Portland cement concrete. They represent a promising building material. It is usually argued that they show high strength, good durability, and good resistance to aggressive agents etc. [1]. These properties were demonstrated not only in many academic papers (see for example [1]), but also in service in many diff erent applications in Belgium, Finland, the former USSR, China, Australia,… [1] On the other hand, AACs are not as usually applied as Portland Cement based concretes are. The practical applications make use of a special mixture composition whose setup is very far from the usual concrete designed from Portland Cement.The practical use of AACs has also been a  long-term topic of interest at ZPSV a.s. company. Some experimental elements have been produced from these concretes [2, 3]. Four rules have been followed : 1) AAC has to be simple to mix ( a minimum amount of compounds), 2) AAC has to be easy to place (self-compacting), 3) AAC has to bring some benefi cial properties and 4) AAC has to be economical. Self compacting AACs with w/c = 0.50 – 0.52 have

been found which fulfi ll the fi rst two rules and partly the third and fourth rules. The frost resistance and the price of the activator show poor properties, though. Mechanical properties and frost resistance can usually be enhanced by lowering the w/b ratio and air entraining. The problem is that common

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plasticizers act poorly in AAC; however, some convenient plasticizers have been found [4]. They allow for a lower w/b ratio towards 0.45 or 0.40.

The paper discusses higher strengths of AAC with a reduced w/b ratio depending on the curing regime, as well as volume exchanges and the development of cracks with the use of acoustic emission.

SESSION W4 16:05–18:00

SUSTAINABILITY IN TUNNELING – CO2-BALANCES DERIVED FROM INVESTIGATIONS CONCERNING THE BRENNER BASIS TUNNEL PROJECT Manfred Keuser, Konrad Bergmeister, Juliane Otto, Hannes Lückmann

Tunnels are important elements of our modern traffi c infrastructure. In addition to technical and economical aspects more and more sustainability and ecology are taken into account in the process of design and construction. The Brenner Basis Tunnel Company BBT SE pays special attention to these aspects. Some information about CO

2-balances of diff erent construction methods and of concrete concepts

which are used in tunnel constructions are presented in this paper. The data show that there is a considerable potential for the optimization of the CO

2-balances.

SESSION W4 16:05–18:00

REHABILITATION OF THE MAIN COLLECTOR SEWER IN BUDAPESTKálmán Koris, István Bódi

Cracks and concrete spalling damages were detected in section IV of the main collector sewer in Budapest. The sewer section in question runs in a  densely populated area of the city and it also passes very close to the Parlament building. To ensure the safe operation of the main collector sewer, a  detailed structural investigation of the aff ected section was carried out. The aim of the investigation was also to fi nd the most appropriate method for the strengthening. After the temporary shoring of the damaged channel section, in-situ inspections were carried out to record the damages, and the general condition of the sewer wall. Destructive and non-destructive material tests were also performed to obtain information about the strength of the concrete in the channel wall. Examination of possible load eff ects on the channel cross-section were analysed by nonlinear fi nite element simulation. The eff ect of the normal surface traffi c, as well as special

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load cases – representing the eff ect of nearby underground construction works – were analysed. According to the analyses, the damage of the sewer was caused by the nearby construction, mainly by the heavy construction traffi c, surface ground deposition and the high-pressure injection of cutoff wall anchors under the main collector sewer. For the refurbishment of the damaged sewer section, diff erent strengthening methods – including GRP and sprayed concrete lining – were considered. The eff ectiveness of diff erent strengthening methods was compared by fi nite element analysis.

SESSION W4 16:05–18:00

APPLIED METHODOLOGY FOR CALCULATING THE STRUCTURAL SAFETY OF TUNNEL LININGS EXPOSED TO FIRERuben Van Coile, Robby Caspeele, Alfred Strauss, Konrad Bergmeister, Luc Taerwe

The structural fi re safety of tunnels has been receiving a  lot of attention since many tunnels are key points in transportation networks. However, few studies focus on the reliability of the tunnel lining during fi re. Determining the reliability of the lining during fi re is important, since an optimization should be based on reliability considerations, taking into account not only the initial construction cost, but also the probability of failure in case of a fully developed fi re. In the presented study, this reliability of individual lining elements during fi re is investigated.

SESSION W4 16:05–18:00

SYNTHETIC AND STEEL FIBRES IN PRESTRESSED, PRECAST LONG SPAN BEAMSGábor Kovács, Károly Péter Juhász

Four large-scale, prismatic, T-shaped beams with 19  m span were produced without stirrups, but 2 with synthetic fi bres and 2 with steel fi bres. Four point bending tests were made to simulate the load bearing process of built-in beams. Three point shear tests were made in the uncracked ends of the beams to prove the shear resistance of FRC. The behaviour of beams made of synthetic and steel fi bre reinforced concrete was compared. Finite element calculation was made with the fi bre reinforced concrete and plain concrete as well. The material model was according to Eurocode and the eff ect of the fi bre was according to RILEM guideline. The numerical and real test load-defl ection results showed close correlation.

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SESSION W4 16:05–18:00

LONG-TERM DEFORMATION OF SRC COLUMNSGyeong-Hee An, Jin-Keun Kim

One of the main mechanisms for creep and shrinkage of concrete is the moisture diff usion. In steel-reinforced concrete (SRC) columns which have been widely applied to high-rise buildings, the wide-fl ange-steel obstructs the moisture diff usion. Therefore, the long-term shortening of the column is delayed due to the slower diff usion, which the existing models cannot refl ect on in predicting the shortening. In this study, an analysis method capable of considering the actual moisture diff usion is adopted. Also, the eff ects of wide-fl ange-steel geometry, column size, and cover depth on the long-term shortening are precisely demonstrated through parametric studies based on the analysis method. The analysis result of plain concrete column is compared with the existing model codes and modifi cation method is suggested for considering the eff ect of the wide-fl ange-steel. This research can give reasonable estimation for predicting long-term deformation of SRC column.

SESSION T1 09:00–11:00

THREE OR FOUR-POINT BENDING TESTS FOR IDENTIFICATION OF MATERIAL CHARACTERISTICS OF FIBER REINFORCED CONCRETEMartin Kovář, Vladimír Křístek, Marek Foglar, Adam Podstawka

Mechanical properties of fi ber reinforced concrete (FRC) are commonly tested on the beam-shaped specimens loaded by bending moment and by the corresponding shear force. The mechanical approach according to the RILEM recommendations, using the three-point bending test of notched specimens (dimensions of 150  ×  150  ×  550  mm, depth of the notch is 25  mm) to acquire fracture characteristics of FRC is assessed. The three-point bending on notched specimens clearly predefi nes the position of the initial crack which generally is not able to respect the actual fi ber distribution; therefore, this type of testing has necessarily higher scatter of the results due to statistically random distribution of fi bers. When the engineering approach according to Czech and German standards is used, the fracture characteristics of FRC are tested using the four-point bending tests. The specimens are beams, 150 × 150 × 700mm, with the span of 600 mm. No notch is used for the predefi nition of the position of the macro-crack. The specimen is loaded by four-point bending. The loading forces divide the span into thirds. The

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benefi t of the four-point bending test arrangement is the constant value of the bending moment with no shear force in the middle third of the specimen and thusly elimination of the eff ect of shear force. At the specimens without the notch, the macro-crack propagates at the weakest cross-section, i.e. at the cross-section with the smallest fi ber content or with unsuitable fi ber distribution. On hand of a simple testing example, the paper compares and discusses two diff erent layouts of testing of mechanical and fracture properties of FRC with respect to the scatter of obtained results.

SESSION T1 09:00–11:00

STRENGTHENING OF STRUCTURES BY TRC AS A CONTRIBUTION TO RESOURCE CONSERVATION USING THE EXAMPLE OF COLUMNSRegine Ortlepp

An extension of the useful economic life of buildings can considerably contribute to the preservation of the building stock. The postponed necessity of new building accounts therewith for an enlarged share in conserved resources. Especially the capacity of the static system to carry the estimated loads in the next decades decides often on the demolition or preservation of the complete building. Columns are important constructional-integrative elements of most buildings’ static systems. Because of their often small load bearing reserves a  subsequent strengthening is often unavoidable, if the structure should be conserved. The increase of the load carrying capacity of columns being reinforced with Textile Reinforced Concrete (TRC) is achieved by both the additional concrete layer and the confi nement eff ect of the textile reinforcement. The eff ectiveness of the confi nement rises with changing cross-sectional shape towards a circle.

SESSION T1 09:00–11:00

EUROCODE DESIGN OF COMPOSITE CONCRETE BEAMSJaroslav Navrátil, Lukáš Zvolánek

Composite concrete beams made of prefabricated prestressed or non-prestressed element and cast-in-place reinforced concrete slab became very popular in present-day civil engineering practice. Two concrete composite parts of beam are cast at diff erent times. Diff erent moduli of elasticity, consecutive load application, and diff erential creep and shrinkage cause unequal strains and stresses in two

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adjacent fi bers of construction joint. The requirement is to ensure that both parts act fully compositely, because the bending and shear designs of composite members are based on this assumption. Therefore the level of shear stresses at the interface between two parts must be limited. The objective of the paper is to review the methods for the calculation of shear stresses in construction joint, and to evaluate the infl uence of diff erent age of two concrete composite parts on the level of shear stresses. Calculation method alternative to Eurocode 2 method is proposed and tested. It is recommended to calculate the shear stress from diff erence of normal forces acting on sectional components in two neighboring sections of the element. It was observed that diff erential shrinkage of concrete components can signifi cantly aff ect the stress distribution. Numerical studies were performed based on real-life examples of composite beams.

SESSION T1 09:00–11:00

COLLECTION OF EXPERIMENTAL CONCRETE TEST DATA FOR MODEL CALIBRATION AND VALIDATIONRoman Wendner, Jan Vorel, Marco Marcon, Gianluca Cusatis

In order to calibrate and validate diff erent constitutive models which have been developed to describe behavior and failure of concrete, experimental data of suffi cient quality covering diff erent experimental setups are required. Unconfi ned and confi ned compressive tests, direct or indirect tension tests are desired to well calibrate concrete models. To  reproduce the damage evolution and the softening behavior, also post-peak data have to be acquired. This paper provides a comprehensive set of concrete test data, cast from the same batch in order to promote the application of advanced concrete models. Flexure tests of four sizes, confi ned and unconfi ned compression tests, as well as Brazilian splitting tests of fi ve sizes, and loading and unloading data included in the database (http://www.baunat.boku.ac.at/comprtest.html) are available for the model development, calibration, and validation. For all specimen sets, the nominal stress-strain curves and crack patterns are provided.

SESSION T1 09:00–11:00

SHRINKAGE STRAIN IN THICK CONCRETE ELEMENTSJan L. Vítek, David Čítek, Jiří Kolísko

Cracking can infl uence the durability of concrete structures. The research laser centre which is built close to Prague is an important building, where the client required almost complete elimination of cracking in massive walls and slabs.

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In order to verify the concrete technology and the effi ciency of reinforcement large scale elements were built before the start of construction. The strain measurements and numerical analyses were used for verifi cation that the stresses in concrete will be small enough that the cracks will not appear.

SESSION T1 09:00–11:00

MEASUREMENT OF SHRINKAGE ON CONCRETE SPECIMENSThomas Zimmermann, Alfred Strauss, David Lehký, Drahomír Novák

Shrinkage potential of a  concrete mixture is an important factor for hardened concrete as it is used as building material in engineering structures. All concrete shrinks, because of a  loss in volume. When concrete is exposed to its service environment it tends to reach equilibrium with that environment. If the environment is a dry atmosphere the exposed surface of the concrete loses water by evaporation. The rate of evaporation will depend on the relative humidity, temperature, w/c-ratio and the area of the exposed surface of the concrete among others. Concrete shrinkage can lead to cracking when free movement of structural members is restrained. After hardening, concrete begins to shrink as water not consumed by cement hydration leaves the system. This is known as drying shrinkage. Water above that necessary to hydrate cement is required for proper workability in the construction process. In general, the higher the additional water content, the higher the shrinkage potential. Concrete drying shrinkage can be measured in the laboratory e.g. according to the standard ASTM C157 or ONR 23303. In this contribution the shrinkage potential of two diff erent concrete strength classes (C40/50 and C50/60) are determined according to ONR 23303 as well as a novel technique by using laterally applied strain gauges. Experimental results of the two diff erent concrete strength classes are presented and discussed and the two diff erent measurement methods are compared to each other.

SESSION T1 09:00–11:00

NONLINER ANALYSIS OF TROJA BRIDGE IN PRAGUEJan Červenka, Jan L. Vítek, Vladimír Červenka

Nonlinear analysis was used to verify the extent of cracking and crack widths in the end segment of Troja Bridge in Prague. The bridge has a main span of 200.4 m, and it is a  simply supported bowstring-arch type bridge with two longitudinal

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pre-stressed steel-concrete chords. The deck slab is 36 m wide, and is composed of prefabricated cross-beams with cast in place concrete deck, which is pre-stressed in both longitudinal and transverse directions. The paper presents results from a nonlinear analysis, which consisted of the 3D model of 1/4 of the bridge including all concrete, steel elements as well as the cables. The analysis simulated the whole construction process, and its main objective was to verify the cracking in the massive concrete slabs above the supports at the bridge ends. The nonlinear analysis proved that the cracking would not be extensive, and the crack widths would remain in acceptable limits. This enabled the elimination of additional very short pre-stressing cables in these segments, which reduced the bridge cost as well as simplifi ed the construction process.

SESSION T2 11:30–13:15

PRECAST SANDWICH PANEL – INNOVATIVE WAY OF CONSTRUCTIONIvana Banjad Pečur, Bojan Milovanović, Ivana Carević, Marina Alagušić

In the period of Global crisis, construction industry is one of sectors that have suff ered the most. It is evident that new ideas, new approach in design of structures and the use of “green” construction materials together with environmental awareness will result with revival of construction market and economic recovery. Existing buildings are responsible for more than 40 % of global energy use, i.e. in Croatia 83 % of buildings consume from 150 to 200 kWh/m2/a just for heating. It’s obvious that future of civil engineering are, not only low-energy buildings, but whole low-energy cities.The construction sector consumes vast amount of natural resources and produces signifi cant quantity of construction and demolition waste (CDW). A proper CDW use leads to effi cient and eff ective use of natural resources and helps mitigate the environmental impacts to the Planet. The Waste Framework Directive requires Member States to take necessary measures to achieve a minimum target of 70 % (by weight) of recycling CDW by 2020. The fact that in most European countries disappointingly small percentage of CDW is being reused, illustrates the possibility of expanding a  construction market in Europe by reusing CDW for new ‘’green’’ materials. Concrete, as one of the most used construction materials, can be used to produce energy and resource effi cient products. Based on these facts, this paper represents one solution for the Period of Economic Recovery: ECO-SANDWICH® – an innovative ventilated prefabricated concrete wall panel with integrated Ecose® mineral wool insulation. It allows very low energy design and retrofi t of buildings, reuse and recycling of CDW (all in accordance with 6th and 7th Basic Requirement for Construction Works). It resulted

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from collaboration between academic community and construction industry and on principles of ‘’turnkey’’ construction provides user a  high quality, aff ordable, energy saving and aesthetically attractive concrete building.

SESSION T2 11:30–13:15

DESTRUCTIVE TESTS OF PRESTRESSED UHPC BEAMS Jan Tichý, Jiří Kolísko, Milan Kalný, Jan Komanec

The paper follows previous presentations on experiences with ultra-high performance concrete (UHPC) in the Czech Republic. After a series of laboratory tests and production trials in the Precast Plant of company Skanska a. s., several prestressed UHPC beams were manufactured. The last set of prestressed beams was stored over winter at a storage yard of the precast plant in Štětí. Two of these beams were destructively tested in February 2014. The other two beams are monitored for long-term changes under constant load. Description of the tests and their results are published in this paper. Concurrently Klokner Institute of the Czech Technical University performed a  number of accompanying tests. During the paper presentation a short video of destructive tests will be shown.

SESSION T2 11:30–13:15

SHEAR CRACKS IN THE THIN-WALLED PRESTRESSED ELEMENT – NUMERICAL AND EXPERIMENTAL ANALYSISJan Hamouz, Lukáš Vráblík

The thin-walled prestressed concrete beams enable to bridge relatively large span. These structures have advantages in economic and environmental way due to their thickness and lower consumption of materials. The normal stress caused by bending moments can be eff ectively eliminated by prestressing. However, the shear forces can cause unexpected cracks in the web if the straight cables (or unfavourable prestressing arrangement) are used. The principal tensile stress arises in the web of the thin-walled element. Eurocode 1992-2 for design of the concrete bridges introduces the direction-dependent tensile strength f

ctb in the informative appendix

QQ. This material characteristic reduces normal tensile strength fctm

due to the acting principal compressive stress. There is no term in the Model Code 2010 such a  direction-dependent tensile strength. The assessment of the arise of the shear cracks in the webs of beams only can be done by comparing acting principal tensile stress and tensile strength f

ctm. This paper is focused on the numerical analysis of the

simple structure and also on the experimental verifi cation of computation.

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SESSION T2 11:30–13:15

FIRST APPLICATION OF PRESTRESSED CFRP LAMINATES WITH GRADIENT ANCHORAGE IN STRENGTHENING POST-TENSIONED CONCRETE BRIDE IN SZCZERCOWSKA WIEŚRenata Kotynia, Julien Michels, Michal Staskiewicz, Christoph Czaderski, Masoud Motavalli

The TULCOEMPA project is Polish-Swiss collaboration between the Technical University of Lodz (TUL, Poland) and EMPA (Switzerland) in research and development of  innovative methods for structural strengthening of existing bridge infrastructure and  subsequent life-long monitoring using advanced wireless systems. The main aim of the project is a pioneer application of innovative strengthening system with prestressed carbon fi bre reinforced polymer (CFRP) laminates on an existing bridge over the Pilsia River in Szczercowska Wieś (central Poland). The second project goal is to integrate information and communication technologies (ICT) to support the eff ectiveness of this strengthening technique by continued long-term structural health monitoring (SHM) and environmental monitoring of the structure. The project involves laboratory tests of two girders and a fi eld application of the proposed strengthening technology.

SESSION T2 11:30–13:15

SHEAR-FRICTION BEHAVIOR OF TRADITIONAL AND SELF-CONSOLIDATING CONCRETE IN REINFORCED PRECAST ELEMENTS WITH IN-SITU CONCRETE OVERLAYFlorian Junker, Klaus Holschemacher, Torsten Mueller

Bonded and reinforced concrete overlays are widely used for precast elements which receive an in-situ overlay. The performance of such overlays relates mainly to the shear-friction behaviour provided by the shear-friction reinforcement. The regulations of  Eurocode 2 for shear at the interface between concrete cast at diff erent times eliminates the usage of Self-Consolidating Concrete (SCC) and shear-friction reinforcement (inclined against the direction of the interface shear force; α  > 90°). In this paper, the shear force transmission across an interface between concrete cast at diff erent times were studied. Here, SCC is used as substrate interface and lattice girders are used as shear-friction reinforcement. The lattice girders considering two diff erent bar diameters (5 and 7 mm) and diff erent

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arrangement of the lattice girder diagonals (in and against the direction of the interface shear force and both). Altogether ten full-scaled specimens were tested. For the  tests, the interface was placed as a “cold joint” with SCC placed in the bottom layer and allowed to cure for 7 days prior to the placement of the upper layer of the interface with traditional concrete. The major outcome of this study is that SCC provides a suffi cient roughness to activate the shear-friction mechanism. This study confi rms that the inclination of the shear-friction reinforcement in the direction to the interface shear force improves residual resistance after a slip.

SESSION T2 11:30–13:15

RECONSTRUCTION AND STRENGTHENING OF LONG VIADUCT MADE OF PRESTRESSED LIGHTWEIGHT CONCRETEMarek Salamak, Boguslaw Markocki

Viaduct made of prestressed lightweight concrete over the market square in Chorzow has been in operation for nearly 35 years. Although it is located within the main national road, the management of this large facility is at the discretion of the city whose budget is too small to carry out a full renovation of such a large and complicated viaduct. As the decision made in the 70s regarding the construction of the facility in the city center still raises emotions among the residents of the city, the deconstruction of the viaduct and restoration of the original function of the market square have been a subject of heated discussions for several years.

SESSION T2 11:30–13:15

WHAT’S NEW IN CREEP OF CONCRETE IN fi b MODEL CODE 2010? Janusz Hołowaty

Advances in concrete technology and the adoption of new materials have required the calibration of a new model for creep of concrete in fi b Model Code 2010, which has a wider range of concrete strengths. The main factors aff ecting the prediction of concrete creep are limited to code-type levels. To describe creep, a well-established concept for basic creep has been developed. In the paper, for the presentation and comparison of creep deformation, creep coeffi cients and creep function are used as the most common and comprehensive parameters for the time-dependent analysis of concrete structures. The fi b MC10 model for creep introduces improvements in the analysis and assessment of the time-dependent deformation of concrete structures. Comparison with previously used creep

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models allows it to be stated that MC10 generally gives even higher values of fi nal creep deformation than Eurocode 2.

POSTER SESSION

P01

EXPERIMENTAL AND THEORETICAL FLOW OF THE FORCES IN DEEP BEAMS WITH CANTILEVARKrystyna Nagrodzka-Godycka, Anna Knut, Kamila Zmuda-Baszczyn

This article presents the results of experimental research carried out on deep beams with cantilever which was loaded throughout the depth. The main deep beam was directly simply supported on the one side. On the other side the deep beam was suspended in another deep member situated at right angles. All deep beams created a spatial arrangement. The paper is focused on the analysis of the cracks morphology and fl ow of the internal forces in the cantilever deep beams. Experimental results in comparison with the theoretical as well as the current design recommendations were discussed.

P02

EXPERIMENTAL STUDY ON CONCRETE WITH HIGH MODULUS OF ELASTICITY FOR TALL BUILDINGS Tianyuan Fan, Zongjin Li, Christopher Leung, Herbert Zheng

A  new type of concrete, which contains volcanic aggregate, having both high strength and high modulus of elasticity has been developed for tall buildings, and its properties were characterized. The structural deformation of high-rise buildings under horizontal loading can be substantially reduced by using this type of concrete, thereby decreasing the cross-section area of the structural members and increasing the economic benefi ts, not to mention alleviating shrinkage and creeping problems of concrete. Uniaxial compression tests, dynamic and static elastic modulus tests were conducted to measure the mechanical properties of concrete specimens with diff erent types of coarse aggregate, fi ne aggregate as

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well as diff erent proportions of sand/coarse aggregate ratio. The eff ects of diff erent replacement ratios of cement by silica fume were also analyzed. The experimental results showed that the water/cement ratio was the key issue in determining the concrete stiff ness. Coarse and fi ne aggregate had signifi cant eff ects on modulus of elasticity but had limited eff ects on compressive strength. A higher proportion of silica fume led to a higher long-term elastic modulus, while a lower sand ratio did not contribute much to enhancing stiff ness. The concrete modulus, which increased dramatically at early ages, attained over 90 % of the 28-day value within seven days. A  particular concrete with the cylindrical compressive strength of 110 MPa and extremely high modulus of elasticity of 51.5 GPa was developed for tall buildings, without much additional cost.

P03

INDIRECT DETERMINATION OF SUPPORT REACTIONS IN CONCRETE BRIDGE ELEMENTSMarek Salamak, Piotr Klikowicz

Many bridges, which have recently been constructed, pretend to be iconic structures. It leads designers to fi nd more ambitious solutions and to design bridges with unique forms and structures. This complexity of the structure is one of the reasons of the Structure Health Monitoring systems evolution. Monitoring of support reactions and, in particular, its value amplitudes allow to validate design solutions and to detect unforeseen external infl uences like diff erential support settlements. This paper describes the phenomena leading to variety of support reactions occurrences such as: torsion of superstructure, diff erential support settlement, inappropriate bearing layout or the impact of mining on the land surface. The idea of determining the support reactions in bridge structures by measuring deformations in concrete bearing pads located directly under the bearings is presented.

P04

OPTIMIZATION SYSTEM MORAVAMONT FOR CONSTRUCTION IN SEISMIC CONDITIONS Živko P. Cuckić, Vesna Cuckić

Therefore, according to the proposed order of this project, by the usage of the new elements in the adhesion prestressing, it is possible to surmount these spans also in the beam prestressing system without post-tensioning which is the case

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in the IMS system. By the usage of prestressed hollow slabs on the pathway that have been used for quite a long time, as well as double ‘’P’’ slabs (by the usage of the universal prestressing on the pathway a quality monolithic joint is set up (by the reinforcement discharge from the above mentioned elements and a column). Apart from the technological calculation this joint is confi rmed both by structural analysis as well as a dynamic calculation according to the ‘Tower’ system for P +12 storey. Seismic infl uences are taken over by the canvases used in the panel system. All further research studies were carried out at the Institute of Seismology – IZIS in Skopje IZIS under the supervision of prof. Predrag Gavrilović.

P05

TENSILE CHARACTERISTICS AND STRENGTH CLASSES OF SFRCVáclav Ráček, Jan Vodička, Jiří Krátký

There is still small use of FRC (Fibre Reinforced Concrete) for FRC load structures, despite increase in its production. Interest of structural engineers and investors still increase in application of FRC load structures, which don´t only increase their safety and durability, but also brings economic eff ect. The main barrier is the absence of design and implementing standards.The paper includes extract from the prepared Czech standards (ČSN):a) Fibre Reinforced Concrete (FRC) – specifi cation, performance, production

and conformity ČSN 73 2450,b) Testing of fresh Fibre Reinforced Concrete (FRC) – ČSN 73 2451,c) Testing of hardened Fibre Reinforced Concrete (FRC) – ČSN 73 2452.Principles, which are included in standards, concern the assessment of fresh and hardened fi bre reinforced concrete, which results in classifi cation into FRC strength classes.The paper is dedicated to the tensile strengths of FRC, whose values must be stated in the characteristic strength class of FRC, because they characterize its advantages over plain concrete.The basis for determining characteristic tensile strengths of FRC is the dependence of F/δ recorded during the bending test on beams size of 150 × 150 × 700 mm (theoretical span of 600 mm), by the so-called four-point loading arrangement of beam. Diagram F/δ can also be called the diagram of resistance, in which are calculated characteristic tensile strengths for the agreed defl ections δ

t. Tensile

strengths are presented in ČSN 73 2450 in the strength classes of FRC.The paper contains the calculation procedure of the tensile strength classes in selected cross sections of the diagram of resistance F/δ, including picture of course of stress at the selected sections, that best describes the behaviour of FRC.

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P06

STUDY ON ULTIMATE STRENGTH AND FAILURE MECHANISM OF RC MEMBERS DUE TO INTERACTION BETWEEN TORSION AND OTHER SECTIONAL FORCERyohei Yanagida, Katsuki Kondo, Takahisa Okamoto

This paper analyses the ultimate strength and the cracking phenomena of reinforced concrete (RC) members subjected to bending, shear, and torsion as well as axial compressive force and torsion.The Great Hanshin Earthquake in 1995 destroyed a number of RC bridge piers of the Hanshin Expressway. According to photographic analysis of damaged RC piers, some were found with diagonal cracking and fl exural cracking formed together. This type of cracking pattern is found on RC members simultaneously subjected to bending, shear, and torsion, and the ultimate strength of RC members decreases remarkably by torsional moment. Although a  number of fracture mechanic studies resulting from failures caused by the Great Hanshin Earthquake have been reported, the eff ect of torsion on RC piers are yet uncertain. Thus, understanding the mechanism of torsion on RC structures is needed for the development of RC structures design. First, the eff ect of torsion on RC members simultaneously subjected to bending, shear, and torsion are studied experimentally for the purpose of examining cracking pattern and ultimate strength. Second, under the same loading condition, the cracking pattern, principal strains, and ultimate strength are analyzed by using a non-linear fi nite element approach. Finally, experimental and analytical investigation of RC members under torsion and axial compressive force are compared in order to understand the failure mechanism.

P07

DOWN THE DRAIN: DOES SURPLUS POUR MATERIAL HAVE POTENTIAL?Amy L. Bauman

In a typical concrete pour, the contractor will order 1 – 3% surplus, to adjust for spillage. This surplus generally goes back to the concrete company to be made into blocks. In  Massachusetts, it is illegal to pour excess concrete on site. We tested the idea of having a city keep a “concrete mould library”, where a certain number of moulds could be loaned to contractors willing and able to create useful products (further customized by local artisans, and bought back by the city at a  fraction of the usual cost). The initial idea was for a voluntary, cost-neutral,

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value add program, where forms are used only when/if there is excess concrete, a willing and able contractor, and a project spec that allows for participation. The study interviewed city recycling coordinators, parks and recreational employees, contractors, building material reuse centres, and aggregate companies. The hypothesis hoped for cost-neutrality for the contractor, cost savings for the city, lower carbon footprint for the project, and a  bit of fame for a  handful of artists. The results surprised us. The state environmental offi cial pointed out that it is illegal to pour excess on site anyway, so the issue is one ‘owned’ by the aggregate company. Concrete companies were quick to point out that concrete quickly loses its workability, and there is neither time nor expertise for a foundation pour team to set up intricate, artistically-embellished form pours. And then … the resulting item is now quite heavy, as foundational blocks are a  ton or more. What PSI standard would the items need to meet, and who provides quality control for the production? Who will move the items, and where will they be stored for future use? How would the municipality explain the lost business to existing contracts for park benches (which are more likely made from steel) and the like? It seemed as though our research would be poured into a  waste container1. The team continued to interview … the basic idea was novel and had broad appeal as new and collaborative. We conclude that smaller products with after-the-fact artistic touches are best. The concrete may be supplemented with shredded, recycled plastic (or wood) to make the resulting product lighter. We avoid designing products that require high quality control (complex forms, or  structural/paving blocks that need to meet PSI standards) and prefer products such as planters and modular raised bed building blocks. Finally, to avoid disruption of  municipal or state contracts, the idea would be marketed to building material reuse charities as a value-added product for sale to the public as “rescued concrete”.

P08

CONTEMPORARY MODELS FOR SHRINKAGE IN CEMENT CONCRETEJanusz Hołowaty

Contemporary models for shrinkage in cement concrete are generally used to express volume changes in concrete without external loads. The models are calibrated, using many years’ theoretical and experimental research works which tried to follow the development of concrete technology and allow for better estimation of this phenomenon. For practical application many modern models

1 One response, from a decades-old institional recycling network: “I don‘t think I can be of any help.  I think it‘s a nice idea, but I cannot believe there would be a positive benefi t: cost ratio for anyone involved.  Best, ML”

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are adjusted for initial parameters available at the design stage. Comparison of development over time and fi nal values of shrinkage strain for diff erent models indicate that the calculated results may diff er signifi cantly. Due to advances in concrete mixes and types of cements, contemporary models usually estimate higher values of fi nal shrinkage in ordinary concrete than the previously used models.

P09

ASSESSMENT OF SPAN PRECAMBER IN PRESTRESSED CONCRET E FLYOVER CONSTRUCTED ON MOVABLE SCAFFOLDINGJan Biliszczuk, Robert Toczkiewicz

Among the bridge structures constructed along the motorway ring road of Wrocław (Poland) there are several multi-span prestressed concrete viaducts with a  total length of few hundred meters. Erection of many structures at the same time resulted in the necessity for proper, optimal selection of the construction technology. A  movable scaff olding system (MSS) was used for the construction of the E1 fl yover of the Rędziński Bridge. This technology demands a  precise calculation of span precamber compensating defl ection infl uenced by the scaff olding deformability, post-tensioning and static scheme changes during span-by-span method of construction. Omission of those factors may result in deformation of the grade line profi le, reduce usability of the structure, and in some cases may also aff ect aesthetic perception of the bridge.

P10

FLEXURAL STIFFNESS ANALYSIS OF RC BEAMS STRENGTHENED WITH FRP SHEETSTomislav Brozović, Tomislav Kišiček, Goran Puž

In this study, theoretical analysis of fl exural stiff ness of the RC beams strengthened with FRP sheets is presented. Flexural static stiff ness of the simply supported beams loaded with distributed load was investigated. Static stiff ness of the beam was shown as a  function of external load and defl ection, hence the defl ection analysis model was calculated fi rst. Numerical defl ection analysis model of the RC beam strengthened with FRP is based on the curvature analysis of cross sections along beam axis, wherein the curvature of each cross section is determined from the three point bending moment – curvature diagram. The paper is completed with defl ection and stiff ness comparison of non strengthened and strengthened beam.

ABSTRACTS

C C C M E M B E R C O U N T R I E S

Central EuropeanCongress onConcrete Engineering

CCC 2015Preliminary Invitationand Call for Papers

HAINBURG 2015The 11th Central European Congress on Concrete Engineer ing

Innovative Concrete Technology in Practice

1 – 2 October 2015Hainburg, Austria

Host CCC AssociationAustrian Society for Construction Technology

www.CCC2015.atCongress website

Preliminary Invitation and Call for Papers

11th CCC-Congress Center

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