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M-2 TRENCHLESS TECHNOLOGY SPECIAL SUPPLEMENT www.trenchlessonline.com

Features6 MANAGING

MICROTUNNELING RISKSMicrotunneling projects have a track record of having a higher than normal rate of claims and extra costs. This mixed record has resulted in a gradual but definite trend on the part of owners and their design consultants to supplement standard bid documents with special provisions in order to minimize the risk of project failure and significant claims. By John Parnass and Kimberlie Staheli

10 THREADING THE NEEDLEDLB uses an innovative solution to overcome the challenges of a mixed-ground alignment to complete a project in Lynchburg, Va.

12 TECHNICAL PAPER: MICROTUNNELING IN GRAVEL, COBBLES AND BOULDERSPerhaps the most challenging ground condition for microtunneling is a full face of wet, cohesionless, high permeability gravel with cobbles and boulders (GCB). This paper discusses the challenges of microtunneling in gravel, cobbles and boulders and potential solutions to mitigate risk. By Steven Hunt and Don Del Nero

16 BREAKING NEW GROUNDWard and Burke and Munro Ltd. team to bring microtunneling to Ontario.By Theresa Erskine

18 MICROTUNNELING FOR THE FUTUREAurora, Colo., builds new Tollgate Creek Interceptor to provide adequate sewer capacity to serve a growing population.

20 MICROTUNNELING ACHIEVEMENT AWARDJames Kwong of Yogi Kwong Engineers will receive the Microtunneling Achievement Award for Engineering Excellence at the Colorado School of Mines Microtunneling Short Course Feb. 12-14 in Golden, Colo. By Jim Rush

22 PILOT TUBE MICROTUNNELING A WIN IN KENTUCKYMidwest Mole recently completed the Shively Interceptor project for the Louisville-Jefferson County Metropolitan Sewer District, representing one of the large pilot tube projects in the United States to date. By Jim Rush

24 TAKING MICROTUNNELING TO NEW HEIGHTSRecent innovations have expanded microtunneling technology into the pipeline and mining sectors. By Werner Burger, Diana Pfeff, Benjamin Künstle and Dr. Gerhard Lang

26 CRITICAL MASS.New England sees an increase in the use of fiberglass pipe.

Departments28 JOB LOG

A look at some of the recently completed and current microtunneling jobs in North America.

31 PRODUCTSInnovative new products available in the market are showcased.

32 DIRECTORYA who’s who of microtunneling manufacturers, suppliers and contractors.

Table of Contents

On The CoverFrank Coluccio Construction Co. recently completed the final drive of the Beachwalk WWPS to Ala Moana Park project in Honolulu. The fifth and final drive included the first double-curve microtunnel drive, as well as the longest drive length for a curved drive, completed in the United States and Canada. See page 4 for details.

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Publisher Bernard P. Krzys

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Steven R. Kramer, P.E. HNTB, Washington, D.C.

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Just as we were closing this issue in October, Frank Coluccio Construction Co. (FCCC) completed tunneling on the final drive of the

highly anticipated Beachwalk WWPS to Ala Moana Park project in Honolulu. The fifth and final drive included the first double-curve microtunnel drive, as well as the longest drive length for a curved drive, completed in the United States and Canada.

The entire $37.1 million project involved five 72-in. microtunnel drives totaling 5,800 lf, and construction of five shafts to a depth of 55 ft. FCCC used a Rasa DH-1800 microtunnel boring machine and a guidance system from Tokyo Keiki Engineers to complete all drives. Ancillary microtunnel equipment was provided by Microtunneling Inc. The final, multiple-curve drive totaled 1,241 lf. Each shaft location had its own unique set of challenges. Several locations had multiple entities, which dictated where construction needed to take place. Coluccio successfully met the needs of each entity, as well as that of the client, the City and County of Honolulu.

Coluccio chief estimator Don Bergman credits teamwork on the part of the FCCC crews for the success of this challenging project. “Microtunneling, when it gets to the this level of difficulty is as much art as it is science, and our lead microtunnel technician, Rene Inasanto, and the tunnel crew drove the machine to perfection. They did a great job of anticipating problems and keeping the project on track.”

He also credited the City and County of Honolulu Department of Design and Construction (DDC) for their willingness to think outside of the box on this project. Bergman also credited the project design team headed by R.M. Towill Engineers for their leadership on the overall design, and particularly Yogi Kwong Engineers, which led the microtunneling design and geotechnical effort. “One thing that was very helpful is that the geotechnical data provided at the time of the bid was very characteristic of what we actually encountered,” Bergman said. “There weren’t any surprises with regards to the

soils.” Construction management on this groundbreaking project was administered by Aecom Engineers.

The project began near the Ala Wai Elementary School and concluded at the east entrance of the Ala Moana Beach Park. This large pressure line will connect to dual 36-in. pressure lines and convey wastewater from the Beachwalk Pump Station to the existing 69-in. gravity line in Ala Moana Beach Park. The project was designed to replace temporary pipelines that were installed after a massive pipeline break in 2006.

Upon completion, the shafts will be converted to permanent man/equipment shafts to enable future inspection and maintenance access to the line. Coluccio recognized the parties involved in the project, including the City and County of Honolulu, Yogi Kwong, R.M. Towill, Aecom, Rasa, Tokyo Keiko and Microtunneling Inc.

The Beachwalk project drew attention as the first project to be designed and bid as a curved microtunnel in the United States, although Northeast Remsco completed the first curved microtunnel drive for the Metropolitan District Commission in Hartford, Conn., in 2010 in place of what had originally been designed as an open-cut installation. We will provide a more detailed article in a future issue of Trenchless Technology.

Honolulu will remain very active for microtunneling over the next couple of years with upcoming projects that include the Honolulu Seawater Air Conditioning project that includes more than 8,000 ft of microtunneling, and the next phase of the Ala Moana sewer project, which involves 15,000 ft of microtunneling. As part of that project, a Herrenknecht VSM shaft drilling machine will be installing 10-m diameter shafts to depths of 100 ft.

Regards,

Jim RushEditor

M-4 TRENCHLESS TECHNOLOGY SPECIAL SUPPLEMENT

North American Microtunneling 2012 Industry Review

First Double-Curve Microtunnel Completed in United States

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Course DirectorsTimothy CossLevent Ozdemir

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While there have been many successful microtunneling jobs completed in the Unit-ed States since the method

was introduced here in the 1980s, mi-crotunneling projects still have a track record of having a higher than normal rate of claims and extra costs. This mixed record has resulted in a gradual but defi-nite trend on the part of owners and their design consultants to supplement standard bid documents with special provisions in order to minimize the risk of project failure and significant claims.

This article describes this growing trend in regards to three key parts of these supplemental contract provisions: bidder qualifications, geotechnical base-lines and equipment specifications.

I. The Early YearsIn the early years, it was fairly com-

mon for owners and consultants to use a traditional approach to bidding jobs involving microtunnel boring machines (MTBMs). At first, many of the projects had performance specifications, based on the traditional approach that the con-tractor bears responsibility for its means and methods and thus ought to select the MTBM that it believes is best suited to the ground conditions indicated in the contract. In addition, subsurface

conditions were indicated primarily by boring logs. If some form of geotechni-cal report was used at all, it was not a baseline report but rather a data report that summarized the boring logs.

This traditional approach began to show its weakness early in the history of microtunneling in the United States. This was due in part to the fact that MTBM equipment has inherent limitations. While it can operate successfully in many soils under high groundwater head, it is also constrained by the fact that:

• The power of the MTBM is limited by its smaller size.

• The face of the MTBM typically can’t be accessed to change cutters or re-move obstructions.

• The contractors tended to use the MTBM heads and machines that were the most economical to obtain rather than design or procure a ma-chine to suit a particular job.

• Soft ground cutterheads on MTBMs tended to get “gravel bound” in soils containing cobbles and gravel.

• Abrasive soils tended to cause ex-treme wear on the face and slurry equipment and reduce overcut.

Due to these challenges, it became ap-parent that relying on the traditional ap-

proach to bidding MTBM jobs needed to be re-examined. With increasing frequency, jobs failed due to differing site condition (DSC) disputes. In claims and litigation, owners began to have to pay settlements because of alleged ambiguities and incon-sistencies in the contract documents.

For example, a specification based on the traditional “let the contractor pick its means and methods” school of thought would be paired in the contract docu-ments with an array of geotechnical bor-ings that did not fully represent the site geotechnical conditions. The contrac-tor would argue that the borings failed to warn of the existence of cobbles or boulders because none were encoun-tered in the drilling. On the other hand, the owner would argue that “everyone knows” cobbles and other obstructions might be present and that the contrac-tor was required to select an MTBM suit-ed to those conditions. This led to many costly disputes and failed jobs.

II. Emergence of New Approach

Due to these issues, some owners are using more innovative methods such as design-build and GC/CM. The City of Portland, Ore., for example, has built extensive MTBM jobs using a best value procurement method where compen-

Managing Microtunneling RisksRevising Contracting Strategies to Help Maximize Successful Outcomes

By John Parnass and Kimberlie Staheli

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sation is based on cost plus fee. These alternative approaches should be (in the authors’ opinions) the wave of the future of the trenchless industry. For the moment, however, we will focus on the most common approach still in use to-day: design-bid-build. The new approach we are about to summarize is based on design-bid-build bidding.

There are three foundations to the new approach being used more com-monly by owners compared to years ago: A) more effective use of specifica-tions to establish minimum require-ments for equipment, B) more effective use of bidder qualifications and C) more effective use of geotechnical baselines.

A. Equipment Specifications. During design of the microtunneling

project, we are increasingly seeing own-ers and trenchless design consultants se-lect the type of microtunneling machine that is best suited to the geotechnical conditions on the project. Generally speaking, the new approach to MTBM equipment is two-fold.

First, when the trenchless design con-sultant has concluded that certain types of MTBMs will be the most successful and certain types of cutterheads and associated equipment are believed to be necessary for success, the specifica-tion will establish mandatory minimum requirements. While this is a departure from the “hands off” approach of prior years, it addresses the unique risks asso-ciated with MTBM jobs and is therefore worth considering on any such job.

Second, when the trenchless design consultant establishes that certain cut-terheads will likely fail in the anticipat-ed ground conditions, the specification will be written to prohibit the use of specific machines – expressly. The most typical example is to prohibit the use of an underpowered soft ground head on an MTBM when the trenchless design consultant is aware of the presence of gravel, cobbles and boulders in the for-mation through which the microtunnel will progress.

An example of what such a specifica-tion would outline follows:

TYPE - Slurry Microtunneling – not manufacturer specific

DIMENSIONS - Minimum base diameter, such as a 48-in. machine

POWER- Large motor to provide cutterhead rotation

- Minimum torque requirements

CUTTERHEAD - Combination cutter with both rock cutters, bullet bits, and drag picks

- Small face openings limiting size of rock that can get ingested

- Reinforced periphery to protect overcut

- Aggressive cutters to handle cobbles/boulders

CRUSHER CONE- Carbide crushing bars- Hard facing on crushing chamber

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By John Parnass and Kimberlie Staheli

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B. Qualifications. Bidder qualification itself is not

novel and has been used for years on MTBM jobs. For instance, many MTBM bid invitations require the low bidder to have certain key personnel (i.e., MTBM operator) and certain company previous success in tunneling mini-mum distances through similar ground conditions. These filters have been – and continue to be – useful. Laws vary from state to state on how to qualify bidders with some states allowing pre-qualification. However, the following assumes that bidders will be screened at the time of bid as part of bidder re-sponsibility review.

What is new is a focus on the low bidder’s equipment. We have seen a growing desire on the part of owners to confirm, as part of the bidder quali-fication review, that the low bidder in fact possesses or plans to acquire the MTBM equipment specified in the con-tract. The advantage to vetting this is-sue as part of the bid award process is obvious. It prevents the awkward and risky situation of awarding the contract to a low bidder on faith that it will mobilize the specified equip-ment – only to discover months into the job, when shedding the contractor becomes more difficult, that it has no intent to bring the specified MTBM.

C. Baselines. In the past, soils information was more

often than not presented merely in bor-ing logs and the occasional geotechnical data report (GDR). This approach some-times proved ineffective, largely because the borings and other data were often capable of being read in various ways and therefore did not yield a single un-ambiguous contract “indication” for use in conjunction with the DSC clause of the contract.

The rising use of baselines, whether set forth in the specification or in a true geotechnical baseline report (GBR), is a positive development but carries with it a new set of challenges. Do not assume that just because you have asked your consultant to prepare a baseline in a specification or in a true GBR that you will in fact be provided with an effective baseline. From the authors’ standpoint, the main challenges in the development of an effective baseline appear to be as follows:

1. Murky Baselines. The GBR is a le-gal contractual document. As a re-sult, you can expect the courts to interpret the baseline language in accordance with well-established rules of contract interpretation. One of those rules is that if con-tract language can be reasonably read to mean two different things, then the contract might be ambigu-ous. An ambiguous contract, in turn, might well be construed against the drafter (i.e., owner). Accordingly, it is imperative that baselines be clear, precise and free of mumbo-jumbo or soft language. Effective use of “defined terms” helps to remove ambiguity.

2. Unnecessary Baselines. Consider whether the proposed baseline really makes a difference to the success of the tunnel drive or the bid price. With MTBM jobs, for example, why dwell on the groundwater head or permeabil-ity along the alignment? Baselines for abrasivity, for example, may not have true meaning if the base-line cannot be correlated to actual machine wear. In addition, it may not be effective to simply specify the number of boulders that will be encountered if not all boulders will necessarily stop the forward progress of the MTBM.

3. Baselines That Can’t Be Adminis-tered. We have seen cobble base-lines on MTBM jobs where the bid-ders are instructed to assume that “20 cobbles will be encountered” along the alignment (or words to that effect). However, most MTBMs larger than 36 in. are capable of and (if the specification is written cor-rectly) are required to crush and ingest a high quantity of cobbles. Once the cobbles are crushed into small particles, it is impossible to “count” the number of in situ cob-bles truly encountered by the ma-chine from analyzing the spoils or the drive records and thus leads to disputes.

4. Establishing Precedence. If a base-line is used, its precedence in re-lation to the underlying data or summaries of the data should be clarified.

III. Final ThoughtsThis article is based on the more

than 35 combined years of experi-ence the authors – a lawyer and an engineer – have had in representing owners on MTBM projects. We want to close with two cautionary notes and a war story.

First, the cautionary notes:

1. Our intent is not to provide tips for transferring unfair amounts of risk to contractors. Rather, our pur-pose has been to take our collec-tive 35-plus years of experience in planning, inspecting and litigating MTBM projects and summarize the main issues that should be consid-ered to maximize success. After all, we are optimists and cling to the belief that everyone in the project, on whatever side, wants to avoid a failed project.

2. Every project is unique. There is no such thing as a canned set of speci-fications or risk factors and associ-ated solutions. We can only offer general suggestions in an article of this length.

Now the war story. To us, it illustrates this point: while a well written set of contract documents tailored to the spe-cial challenges of MTBMs can’t change human nature, they can give owners an easier way out of a sticky situation com-pared to years past.

Not long ago, we assisted an owner on an MTBM project. The glacial till soils were known to be cobbly and abrasive. We knew that a standard soft-ground MTBM without any rock cutters would likely get stuck in such conditions, largely due to the fact that the machine face gets gravel bound when the volume of cobbly material exceeds the torque capacity of the MTBM and its ability to crush and in-gest the material.

Based on this, the owner had us write the MTBM specification in a certain way. We a) prohibited the contractor from using a soft ground cutterhead and b) required the use of a combination cut-terhead with rock cutters and bullet bits. Plus, we required the contractor to keep the machine face openings small in order to limit the amount of material entering the crusher cone.


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The lesson? You can’t write any contract good enough to control the way folks will behave if they are de-termined not to follow the contract, but you can write the contract to 1) maximize the chance of success with a contractor who will play by the rules (which the authors believe to be the vast majority of contractors)

and 2) provide a way out of a sticky situation with the occasional one who will not.

John Parnass, J.D., is a partner with Davis Wright Tremaine LLP, Seattle, and Kimberlie Staheli, Ph.D., P.E., is president of Staheli Trenchless Consultants, Seattle.

In other words, we wanted to avoid this from happening:

by requiring use of a cutterhead that looks like this:

After bid opening (but before authorizing the low bidder to proceed), we required a submittal of the specific MTBM the low bid-der intended to bring to the job. We wanted to match the submittal to the specification in order to verify the low bidder’s capability to bring the required equipment.

The submittal we received, however, de-picted a soft ground cuttinghead on the MTBM, which the low bidder then vehement-ly argued was really a combination cutter-head MTBM. The contractor helpfully offered to mobilize a true combination cutterhead in exchange for a costly change order. The own-er considered this offer and then terminated the low bidder for convenience.


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The James River Interceptor Divi-sion 4 project in Lynchburg, Va., is part of the city’s program to reduce combined sewer over-

flows and improve water quality in the river and its tributaries. But this particular section of the interceptor had a unique problem: about half of the alignment tra-versed soft ground while the other half went through rock. While the change in geology can be dealt with easily enough, the change in geology occurred under-neath railroad tracks, and a change in the alignment was not a possibility.

The solution: use conventional shield tunneling to construct the soft ground portion, then use a motorized small bor-ing unit (SBU) to build the rock tunnel and meet in the middle. This novel ap-proach allowed a successful completion to the project.

Project BackgroundBy the close of the 19th century,

Lynchburg was prosperous enough to follow the lead of urban centers like Bos-ton and San Francisco in the construc-tion of sanitary sewer systems. When the city’s sewer system was first built more than 100 years ago, it was among the finest in the nation, utilizing state-of-the-art technology. Unfortunately, the “state-of-the-art” at the time was to pipe sewage away from densely populated ar-eas ... and into the nearest waterway. As a result, most of Lynchburg’s untreated sewage eventually made its way down-stream into the James River.

By the mid-20th century the short-comings of this approach were apparent, and cities like Lynchburg began building treatment plants to reduce pollution to waterways. In conjunction with the con-

struction of Lynchburg’s treatment plant, which was completed in 1955, a series of interceptors were constructed to connect the city’s 21 drainage basins to the plant. However, these interceptors were de-signed as combined sewers to accommo-date both sanitary and stormwater flows, so during heavy rains untreated sewage can still find its way into the waterways.

To address these overflows, Lynchburg has embarked on a mandated program to build separate sanitary and storm water pipes so that the system is not inundated during rain events. Additionally, the city has rehabilitated more than 100,000 ft of sewer lines and inspected more than a quarter-million ft of underground pipes using special CCTV cameras.

Since agreeing to the Special Order is-sued by the State Water Control Board in 1994, the City of Lynchburg has pro-gressed toward its goal of improving wa-

After terminating its drive within a soft ground tunnel, the Robbins SBU-M, was extracted through the liner plate.

Threading the NeedleVirginia Contractor Uses Innovative Solution to Overcome Challenges

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ter quality. Since Lynchburg’s CSO work began, 102 of the original 132 overflow points have been eliminated, leaving 30 points to be closed in the future. The net result has been a 78 percent reduction in the volume of combined sewer over-flow into the surrounding waterways.

James River InterceptorLynchburg’s largest and longest inter-

ceptor sewer is the James River Intercep-tor. The interceptor is 7 miles long and, at its largest, is 7 ft in diameter. The intercep-tor spans from the Wastewater Treatment Plant along the James River all the way to VES Road, just below Reusens Dam. The construction of the new interceptor was broken into six different divisions. The to-tal cost of construction, which involves multiple installation techniques, is esti-mated to be more than $60 million. When completed, this larger interceptor will eliminate approximately 130 overflow events per year from the James River, and will close four CSO points forever.

The new James River Interceptor in-cludes:

Division 1: Completed in February 2009, this project was located along Concord Turnpike from the Wastewater Treatment Plant upstream to Winston Ridge Road.

Division 2: This project was con-structed by Thalle Construction from Hillsborough, N.C., and was completed in June 2011.

Division 3A: This project, located from the Carter Glass Bridge to 9th Street, was awarded to Thalle Construction and was scheduled to begin in August 2012 and be completed in December 2012. The project encompasses work along Jeffer-son Street and Washington Street.

Division 3B: This project will run through Riverfront Park and is currently under design. Construction dates for Divison 3B have not been determined. This is the last of the James River Inter-ceptor projects.

Division 4: This project is approxi-mately 3,000 ft long and has two tun-nels, the longest of which is over 1,000 ft long under seven sets of railroad tracks. Tunneling on this Division was complet-ed this summer by DLB Construction. Cleanup work is ongoing.

Division 5: This project is located upstream of Griffin Pipe and has been

awarded to Thalle Construction. Con-struction began in July of 2011. Divi-sion 5 work includes installing ap-proximately 4,330 ft of 36-in. diameter gravity sewer interceptor and replac-ing an undersized 24- to 30-in. sanitary sewer line. This project was expected to be completed in September 2012.

Division 6: This project was con-structed by Thalle Construction and completed in July 2011.

Threading the NeedleThe construction of Division 4, built

by DLB Inc. with joint venture partner Webb Construction Co., included a tricky section in which the alignment included a change of geology under-neath railroad tracks. Because stop-ping train traffic to build a pit in the middle of the railroad right of way was not an option, an innovative solution was needed. Interestingly, the tunnel went underneath the tracks – both CSX and Norfolk Southern – for most of its alignment.

The plan was to build pits at either side of the tunnel alignment, launching a conventional 60-in. Akkerman tunneling shield from one pit to mine through the soft ground portion and erect liner plate tunnel. Once the shield reached the end of its run, the machine was disassembled and the shield left in place. From the op-posite pit, DLB used a 54-in. Robbins SBU-M, rented from The Robbins Com-pany, to mine through the rock portion of the tunnel. Rock strength ranged up to more than 20,000 psi.

“We knew our options were limited, so after some discussions with our joint venture partner, we came up with this approach,” said Clyde Roberts, field su-perintendent for DLB. “Once we were able to do some explorato-ry drilling we found that more than 400 ft of the alignment was solid rock, with the other 700-plus ft soft ground. So we decided to use both soft ground and hard rock equipment.”

To aid in soft ground tunneling, chemical grout-ing was used to stabilize a 300-ft section along the railroad alignment to help reduce settlement and cut off ground water flows. Grout holes were drilling

in 3-ft increments and greatly assisted tunneling, Roberts said.

The SBU-M is a modified auger boring system that uses an in-shield motorized cuttinghead to provide torque for cut-ting rock, using the auger boring frame at the pit for thrust. The SBU-M has an articulated cuttinghead for steering in conjunction with a laser. This steering system allows for accuracy of ½ in. over a 500 ft bore. This was particularly im-portant on this project.

“With ID of the liner plate at 59 in. and the OD of the SBU at 56 in., there was very little room for error,” said Kenny Clever, SBU Manager for The Robbins Company. “We had to the bull’s eye to have enough clearance to get inside the tunnel.”

When it reached its destination, it bored into the soft ground tunnel where the SBU was disassembled and pulled through the liner plate tunnel using cables and winches. “We hit the target ¼ in. high and 5/8 in. to the left,” Roberts said.

One of the keys to success, Roberts said, was getting the steering set up properly. “There was some discussion of driving both headings simultaneously to save time,” he said. “But in our opinion it is harder to hit a moving target, so we finished the soft ground tunnel and had a survey log the coordinates to give us an accurate target for the rock drive.”

This article was written by TT staff.

DLB used a 54-in. Robbins SBU-M, rented from The

Robbins Company, to mine a rock tunnel in Lynchburg, Va.

U191_10-11.indd 11 11/1/2012 10:34:22 AM


Perhaps the most challenging ground condition for micro-tunneling is a full face of wet, cohesionless, high permeabil-

ity gravel with cobbles and boulders

(GCB). This ground condition increas-es the risk of potential impacts such as: a jammed excavation chamber (see Figure 1); high torque and microtun-nel boring machine (MTBM) stalling;

excessive overmining resulting in lost ground settlement damage or sink-holes; significant MTBM advance rate reductions; excessive abrasion damage to cutters, cutterhead, rock crusher, in-


TECHNICAL PAPERMicrotunneling in Gravel, Cobbles and BouldersBy Steven Hunt and Don Del Nero

FIGURE 1MTBM choked with gravel and cobbles

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take ports, and slurry mucking system; and impact vibration damage to MTBM gears and bearings. The risk of these potential impacts may make microtun-neling inadvisable, but at least neces-sitate use of special measures to help make microtunneling more manage-able. Comments on the challenges of microtunneling in GCB and potential solutions to mitigate risk are discussed below.

Groundwater ConditionsWet, cohesionless, high permeability

GCB tends to cause several important geotechnical challenges. This ground condition has one of the lowest standup times possible. As the groundwater head increases, the standup time decreases and challenges of providing face stabil-ity increase. Unbalanced heads as small as 1 m (0.1 bar) can cause flowing ground and overmining. Overmining or ingesting more ground than displaced by the MTBM and jacked pipe tends to cause excessive settlements and exces-sive flow of ground into the excavation chamber.

In order to apply an effective face pressure when tunneling in open grav-el or GCB, the subsurface investigation program and geotechnical instrumen-tation should adequately indicate the range in permeability expected and groundwater pressure to be resisted. In many cases, too few piezometers are in-stalled and permeability tests performed to adequately predict groundwater con-ditions along the entire alignment.

Face Pressure and MTBM Slurry

Presuming that permeability and groundwater head are adequately known, the next challenge is to apply an effective face pressure that mini-mizes overmining. To be effective, the face pressure must be at least equal to the groundwater pressure at invert plus a component for active earth pressure. This is a very difficult task in very high permeability ground, which can gener-ally be assumed to be ground with a permeability of 10-2 cm/sec or more. Counterbalancing the water pressure can be readily achieved by pressurizing the excavation chamber to the required level regardless of the slurry mixture be-ing used.

Prevention of flowing ground and overmining is much more difficult. The muck conveyance slurry must have sufficient viscosity and other proper-ties to form a “filter cake” at the head-ing. A thorough discussion of slurries for microtunneling and recommenda-tions for slurry properties for various soil types are given in a 2011 paper by Boyce et al [1].

The muck conveyance slurry for mi-crotunneling in gravel with less than 10 percent fines (< 10 percent passing the No. 200 sieve), should not be wa-ter/soil-only slurry. If the slurry is too thin and a filter cake is not formed, the slurry will excessively flow into the ground and only provide resistance from seepage pressure. Adequate pres-sure to resist ground flow will not de-velop. While water/soil slurry may be suitable for microtunneling in clayey or silty ground, it is not suitable in high permeability, cohesionless soils with less than 10 percent fines. A properly

designed bentonite slurry or bentonite-polymer-additive slurry should be used when microtunneling in high permea-bility gravel to mitigate risk of overmin-ing, a jammed excavation chamber and a stalled MTBM.

Cutterhead OpeningThe cutterhead opening ratio (COR),

which is the percentage of open area on the cutterhead, and size and distri-bution of openings from the center are critically important considerations for microtunneling in GCB. MTBMs typically have CORs ranging from 20 to more than 50 percent. Larger CORs are desired in cohesive soils (firm or slow raveling ground) and smaller CORs in cohesionless soils (flowing or fast ravel-ing ground).

Where the ground has sufficiently low permeability, no active groundwa-ter head and sufficient strength to be stable in an open-face condition, a larg-er COR is also desired in GCB with a

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clast volume ratio less than 2-3 percent (clast volume ratio is the total volume of cobbles and boulders as a percent-age of excavated volume). Larger cut-terhead openings increase the size of clasts that can be passed and minimize the amount of cobble and boulder fracturing required by cutters to be passable into the excavation chamber. While a larger COR helps reduce cut-ter and cutterhead wear and damage, it may increase rock crusher wear since more commutation energy must be ex-pended to reduce rock clasts to gravel size for flow through intake ports and slurry-muck pumping. A larger COR also helps prevent clay clogging at the cutterhead opening.

In high-permeability GCB with a meter or more of groundwater head resulting in potentially flowing or fast raveling ground, a smaller COR is like-ly needed to help reduce the flow of ground into the MTBM chamber and thereby reduce the risk of excessive torque and stalling. The use of thick bentonite slurry or bentonite slurry with polymer or fiber additives may be suitable for small pockets of gravel or high permeability ground, but may not be sufficient to prevent the excavation chamber from getting jammed with excessive cobbles and boulders. Fur-thermore, use of a smaller COR helps reduce dependence on the slurry mix design and ability to rapidly adjust it in changing ground conditions.

Considerable energy is required to crush cobbles and boulders to gravel size for passage through intake ports, slurry lines, elbows, valves and pumps to a separation plant. MTBMs have limited power and torque for use in turning the cutterhead and in crush-ing rocks within the excavation cham-ber. In GCB, the volume of cobbles and boulders that enter the chamber must be limited to reduce the com-mutation energy demand and prevent excessive torque and stalling.

Based on experience from several projects, Hunt and Del Nero 2012 [2] suggested cutterhead opening ratio limits for clast volume ratios ranging from 10 to greater than 40 percent. Where the clast volume ratio exceeds 10 percent, CORs should be reduced to 25 percent or less and may need to be in the range of 10 to 20 per-cent. Where the ground permeabil-

ity is higher, the risk that bentonite slurry will be thick enough is lower and as a result, the COR should be lower (closer to 10 percent). Where the ground permeability is lower, the risk that the bentonite slurry viscos-ity is inadequate is lower and the COR may be higher (closer to 20 percent). Cutterhead opening size and configu-ration should be optimized for the size, distribution, and geometry of the clasts anticipated and the range of soil matrix conditions expected. For instance, if the clasts tend to be planar, then several smaller openings may not be the best geometry even though the cutterhead opening ratio is suitable.

MTBM TorqueThe thrust and torque required for an

MTBM to effectively advance through GCB is dependent on many factors in-cluding: soil density; clast volume ratios; clast sizes and strengths; energy required to fracture, pluck and crush clasts; muck flow friction in the MTBM chamber; in-takes and slurry mucking system; and friction between the ground and MTBM and jacked pipe. GCB with higher den-sity or that is weakly cemented tends to increase the torque required to cut, pluck and pass cobbles and boulders. As the clast volume ratio increases, the torque required increases. In addition to clast volume ratios, the size and un-confined compressive strength of the clasts also influences torque demand. A boulder will generally require more torque to cut and pluck than scattered cobbles for the same clast volume ratio. Torque spikes above that required for general excavation will result when the cutters impact boulders at the face. The sustained energy and torque required to cut and fracture or pluck clasts at the heading increases as the unconfined compressive strength of the rock in-creases [2].

After cobbles and boulders are par-tially cut, plucked and passed into the MTBM excavation chamber, the energy required to crush the clasts to a gravel size for slurry mucking is very high and increases with both increasing clast vol-ume ratio and increasing unconfined compressive strength of the clasts. Torque spikes may also occur when a large, high strength clast is engaged by the rock crusher.

The friction of the slurry and muck rotating through the MTBM crusher and flowing to intake ports is much higher than normal when boring in GCB. It increases as the clast volume ratio increases. Higher friction and resistance to muck flow also results in higher torque demand. Use of an appropriately designed bentonite or bentonite-polymer-additive slurry helps lubricate the muck and to reduce the muck resistance to flow and torque de-mand. In addition to reducing friction, the bentonite also helps to reduce abra-sive wear of the rock crusher, intakes and slurry mucking system [3].

When microtunneling in GCB with a clast volume ratio greater than 10 per-cent, the selected MTBM should be pro-vided with the highest torque available from manufacturers for the excavated diameter and anticipated speed. MTBM upsizing via “skinning up” should not be allowed. Specifying or at least strongly suggesting use of the maximum avail-able torque for the planned excavated diameter is strongly recommended to help reduce the risk of stalling in this ground condition.

Abrasion and WearAnother potential consequence of

using water/soil-only conveyance slur-ry in ground with a gravel matrix and cobbles and boulders is excessive abra-sion, cutter impact damage and wear. GCB muck within water/soil slurry without bentonite is much more abra-sive than in bentonite slurry. A more abrasive slurry results in higher MTBM torque and higher rates of wear of the rock crusher bars and arms, the cham-ber slurry intake ports, the slurry pump and slurry return lines, particularly at pipe bends. Severe intake port wear from crushed GCB may cause MTBM slurry lines to become jammed and ad-vance stopped.

When clast volume ratios are in the range of approximately 3 to 10 percent within a gravel matrix, measures such as use of engineered bentonite-polymer-additive slurry and cutterhead opening ratio reduction are likely needed. When clast volume ratios exceed 10 percent and very abrasive gravel and clasts are expected, microtunneling should be avoided unless special measures are provided to manage the abrasion and stalling risks. These measures might


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include: a combination head with disk cutters; cutterhead and crusher armor-ing; use of bentonite-polymer-additive slurry; use of larger intake ports and slurry lines; use of intake port surface hardening; and minimum TBM cutter-head torque requirements.

Summary of Potential Mitigation Measures for Microtunneling in GCB

The risks of microtunneling in GCB can be mitigated by a variety of poten-tial measures. To microtunnel in high-permeability gravel and to reduce risk of choking and stalling along with the risk of severe overmining and sinkholes, the flow of ground through the cutterhead into the excavation chamber must be restricted to a rate that the rock crusher and slurry mucking system can handle by one or more of the following methods:

• Pre-excavation grouting to reduce permeability and increase strength.

• Use of an engineered bentonite-poly-mer-additive conveyance slurry (not water/soil slurry) that is thick enough to form a “filter cake.”

• Application of a slurry pressure at the face equal to at least the groundwater pressure and estimated active earth pressure.

• Reduction of cutterhead opening sizes and cutterhead opening ratio to less than normal.

• Utilize a MTBM that is not upsized and has the maximum torque avail-able from manufacturers for that di-ameter.

These and other special measures discussed above should help make microtunneling in GCB more man-ageable and minimize the risk of get-

ting stuck or encountering severe impacts.

Steven Hunt, P.E., and Don Del Nero, P.E., C.D.T., are with CH2M HILL.

ReferencesBoyce G., Wolski M., Zavitz R. & Camp

C. 2011. Chemistry And Physics Behind Microtunnel Slurries, Proceedings of North American No-Dig 2011, NASTT, paper A-2-01, (2011.6) 10p.

Hunt S.W. & Del Nero, 2011. Mi-crotunneling in Cobbles and Boul-ders. Microtunneling Short Course, Colorado School of Mines, Golden, CO. 36p.

Milligan G.W.E., 2000. “Lubrication and soil conditioning in pipe jacking and microtunnelling”. Tunnels & Tun-nelling International, July 2000, pp. 22-24.


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Ontario is Canada’s most populous region, with 40 per-cent of Canadians calling the province home. In fact, 7.6 percent of all Canadians live in Ontario’s capital, Toronto – a city that saw a 4.5 percent population

growth between 2006 and 2011.Ontario’s population boom has put severe strain on its aging

existing infrastructure, and has also created a huge demand for new services. So it’s hardly surprising someone saw an opportu-nity, and seized it.

Enter Ward and Burke Microtunnelling , a new Canadian sub-sidiary of Ward and Burke Construction, a company boasting seven years of successful microtunneling projects across Ireland and the United Kingdom. They’re on a mission to bring micro-tunneling to Ontario on a large scale, in collaboration with infra-structure manufacturer Munro Ltd. of Utopia, ON, about 60 miles north of Toronto.

The First ForayWard and Burke’s first project in Ontario came about because

of almost impossible tunneling conditions. They were tasked with installing a new 1,200-mm (48-in.) sanitary sewer tunnel running directly under an existing 1,800-mm (72-in.) concrete pressure pipe water transmission line and an existing creek at Gore Road, in Brampton, ON. Because of the presence of ground-water, cohesionless ground and the 1.5-m clearance between the two lines, settlement to the transmission line was a real threat and traditional open-face tunneling methods were not suitable.

“There really was no other way to do this project,” says John Grennan of Ward and Burke Microtunnelling. “We got the call.”

Drive lengths of 170 m (558 ft) and 150 m (492 ft) in depths ranging between 8 and 11 m (26 and 36 ft) were completed in a four-week period using a Herrenknecht AVN 1200 owned and operated by Ward and Burke.

While working on Gore Road, the company was called to help a watermain project under Avenue Road – a major artery in the heart of downtown Toronto. The existing watermain was constructed between 1915 and 1923 and carries up to 50 million liters per day, distributing water to reservoirs across the city. With the volume of traffic on a road that connects the downtown core with the province’s busiest commuter route, Highway 401, disruption due to construction using open-cut methods was causing serious, fre-quent and vocal complaints from residents and commuters alike. And in a dense, urban environment like Toronto, existing services – including natural gas, telephone, electricity, telecommunications and sewer lines – make open excavation impractical. Finally, the

glacial till geology and high levels of groundwater in and around Toronto make the terrain difficult to work with at the best of times. All challenges microtunneling can tackle with greater ease than open-cut and open-face tunneling methods.

Again, microtunneling was carried out using a Herrenknecht AVN 1200 TBM. The first drive took place on Avenue Road, tun-neling 70 m (230 ft) south toward Chaplin Crescent and the second on Oriole Parkway, tunneling 270 m (886 ft) west under Chaplin Crescent to Avenue Road. Both tunnels were construct-ed in saturated sands with an average depth of 11 m (36 ft).

With the Avenue Road project under way, Ward and Burke got an emergency call for a 100-m project on Lawrence Avenue in Toronto’s east end. The snowball effect was beginning.

Taking It Truly LocalOn those first three Ontario projects, Ward and Burke had

to import the pipe from its parent company’s regular source in Ireland, a costly effort fraught with logistical hoops to jump through. There was no local supplier to turn to, because until now, microtunneling in Ontario was rare at best.

Breaking New GroundWard and Burke, Munro Team to Bring Microtunneling to Ontario

By Theresa Erskine

Ward and Burke’s projects in Ontario include two 318-m (1,040-ft) parallel tunnels, 0.5 m apart, at

Pearson International Airport.

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But during the Gore Road project, Mario Recchia, Technical Director at Munro Ltd., and Gerry Mulhearn, Executive Direc-tor at the Ontario Concrete Pipe Association (OCPA), stopped by for a site visit. Recchia knew his company could meet Ward and Burke’s needs, based on Munro’s experience engineering and manufacturing one of the broadest product line portfolios in the industry, ranging from sanitary and stormwater pipe to freshwater pipelines, bridge components, engineered precast and tunnel lining segments.

“There’s quite a lot of engineering required for microtunnel-ing pipe and reinforced jacking pipe,” says Grennan. “We give Munro the internal diameter and external diameter, the desired length and the jacking forces. They do the structural design and manufacture the pipe specifically for our project and our equip-ment. We always push concrete pipe instead of steel, fiberglass or polymer-concrete. It’s strong in compression, provides joints with good seals, and it’s fast to install.”

On their first collaborative project, the two companies set a new pipe-jacking record in Canada. The project was to construct two new jet fuel lines needed for Toronto’s Pearson International Airport, Canada’s largest and busiest airport. The microtunneling was part of a larger project that included the construction of a rail offloading terminal and a new storage tank system, complete with delivery pipeline to the airport. The system will accommo-date the delivery of aviation fuel by railcar directly into a system dedicated to supplying Pearson with up to 100 percent of its fuel needs for the foreseeable future.

Based on the required tunnel length and diameter of the jet fuel line, Ward and Burke determined that the tunnel lining pipes had to be 1,200-mm ID. The outside diameter of the jack-ing pipe was based on the standard dimensions of the Herren-knecht MTBM used on the job. The reinforcement requirements based on the required wall thickness and loading conditions were calculated by Munro Ltd. engineers, and the pipe was man-ufactured to these specifications by Munro in its 470,000-sq ft (44,000-sq m) state-of-the-art manufacturing facility.

This special design requirement necessitated retooling at Munro Ltd. The pipe for the Pearson project was hydrostati-cally tested in the manufacturing process to ensure it met the design requirements and tunnel boring conditions. The steel band was coated with a red epoxy coating to prevent corro-sion in the ground.

An important feature with the microtunneling system is the ability to lubricate the 25-mm (1-in.) overcut annulus created by the MTBM. Munro Ltd. manufactured special pipes with three lubrication ports, installed every 15 m, in the tunnel alignment. These ports allowed Ward and Burke to effectively lubricate the overcut annulus throughout the drives. The lubrication prevents ground closure, settlement and minimizes skin friction on the pipe. Once the tunnel is complete, the ports in these pipes can be used to grout the annulus.

Two 318-m (1,040-ft) parallel tunnels, 0.5 m apart, were in-stalled at Pearson International Airport. The proximity of the two parallel tunnels is a record in Canada, but most impressively the project caused zero disruption to airport operations or local traf-fic and commerce. In fact, the only visible evidence of the major infrastructure project was a small jobsite right next to Terminal 3 – a launch tunnel shaft, tunneling control room to operate TBM, a separation unit to screen soil fines from suspension, and the stock of microtunneling pipe itself.

“We had to go under and over 45 services on the Pearson project, including through a large number of abandoned duct banks formerly used to house underground electrical services,” says Grennan. “The project team – the general contractor and the management group – was very happy with the result and surprised by the lack of disruption.”

Continued CollaborationThe two companies also seem happy about the results of their

collaboration. In a 15-month period, over 25 microtunnels, ranging in length from 25 to 400 m (82 to 1,312 ft) and ranging in diameter from 600 to 1800 mm (24 to 72 in.), have been installed with a 100 percent success rate. Up next? They are currently working on a proj-ect in Waterloo, ON (hometown of Blackberry inventors Research in Motion, or RIM), a project that will run under Highway 400 in Barrie, ON – the first time a microtunnel will pass under a 400-series highway in Ontario – and further afield projects in Calgary, AB.

“We’re educating municipalities and consultants about the fact they now have choices,” says Grennan. “Before, there was no local vendor for microtunneling, so it wasn’t cost effective. Now they have that opportunity, and can take advantage of all the benefits microtunneling has to offer in terms of speed of construction, reduced disruption and increased environmental responsibility.”

Theresa Erskine, MBA, P.Eng., is director of marketing for Munro Ltd.


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Over the last 20 years, the population of Aurora, Colo., has steadily been on the rise, increasing to about 332,000

from 236,000 in 1992. This rapid increase in population required that the city up-grade its water and sewer infrastructure to keep pace with growing demands, as well as plan for future needs. As a result, the city has initiated large infrastructure proj-ects that have included about 4,500 ft of microtunneling within the last five years.

In 2007, the city began the mammoth Prairie Waters Project, a $653 million water supply project that involved the installation of 34 miles of 60-in. diameter pipeline – just over 2,000 ft of which was microtunneled. Tunneling on that project was completed in October 2009 [North American Microtunneling, 2010, p. 26-27]. On the collections side, the city commissioned a Collection System Service Plan that included a hydraulic capacity analysis of the system. The re-sult: key segments of the collection sys-tem were at or nearing capacity.

City planners first turned their attention to the existing Tollgate Creek Interceptor,

the most critical interceptor in need of upsizing. The Tollgate Creek Interceptor runs from the Tollgate Creek drainage ba-sin to the Sand Creek Interceptor, which then conveys flows to the Metro Wastewa-ter Reclamation District’s Robert W. Hite Wastewater Treatment Plant. City planners decided to build a new, larger intercep-tor parallel to the existing interceptor to handle additional capacity and allow for the existing interceptor to be taken offline and rehabilitated in the future.

Phased ConstructionThe new Tollgate Creek Interceptor

was divided into four phases. Phase I was installed primarily by direct bury in 1996. The PVC pipe ranged from 42- to 48-in. in diameter with a length of approximately 6,000 ft. Phase II was installed primarily by direct bury in 2007, although the installa-tion included a short 200-ft section of jack-and-bore. The PVC pipe size was 30-in. with a length of approximately 9,000 ft. Phase III was installed in 2010. The PVC pipe size was 36-in. with a total length of 6,000 ft. This project included three 66-in. microtun-nels for major roadway and creek crossings.

Phase IV was installed beginning in April 2011 and is on pace for completion in November 2012. The fiberglass-reinforced pipe was 42-in. in diameter with a total length of approximately 10,000 ft – 5,000 ft was installed by direct bury, 2,500 ft by microtunnelling and 2,500 ft by tunnel boring machine (TBM). The tunnels were driven with 54-in. diameter Permalok steel casing in which 42-in. Hobas carrier pipe was placed. The microtunnel drives var-ied in length from 200 to 740 ft. The TBM drives varied in length from 300 to 700 ft.

Selecting the MethodHaving gained experience with micro-

tunneling through the Prairie Waters proj-ect, Aurora Water engaged contractors in selecting the construction methods for the new Tollgate Creek Interceptor. “We did not dictate the installation methods, but rather gave contractors the option to bid to their strengths,” said Swirvine Nyirenda, P.E., Senior Project Manager for Aurora Water. “Additionally, we discussed each reach with contractors during the bid process to help determine the opti-mum way of approaching the work.”

Microtunneling for the FutureAurora, Colo., Builds Sewer Capacity to Serve Growing Population

Of the roughly 5,000 ft of

pipeline installed

trenchlessly, about half was

built using a 54-in. Akkerman

TBM, and the other half was built using an Akkerman SL

51 (skinned up to 54-in.)

microtunneling system.

U191_18-19.indd 18 11/1/2012 10:36:05 AM

ated how much ground treatment and dewatering would be necessary to use a TBM, compared to running our micro-tunneling system.”

Tippets said that careful monitoring of the slurry returns was key to suc-cessful microtunneling. “Not only did the ground change from manhole to manhole, but also within each reach,” he said. “We constantly tweaked the system

to be able to handle the different soil materials. I don’t think we went more than 10 ft before the soil changed again.”

When the project is completed the city will divert flows into the new in-terceptor, allowing the old interceptor to be repaired and ensuring the long-term needs of the growing population.

This article was written by TT staff.

While Aurora Water allowed options for each approved construction method – open cut, microtunneling, TBM tunneling – plan-ners worked with Phase 4 designer CDM Smith to develop an appropriate framework for construction. “Each option was engi-neered so that when the contractor select-ed an installation method, there were con-ditions in the contract appropriate for that specific method,” Nyirenda said.

Aurora Water used a low-bid procurement method, but used a prequalification process in which bidders were approved based on the experience of the company and the per-sonnel who would be assigned to the job site. A geotechnical baseline report (GBR) was also used within the contract documents as a way to reduce contingencies in the bids.

Trenchless construction methods were not as prevalent in the early phases of the project, which were located in less devel-oped areas of the city. In Phase 4, about half of the 10,000 ft of pipeline was installed us-ing tunneling or microtunneling techniques.

“One of the overriding factors for select-ing the construction method was whether we had a major roadway or major creek crossing – if we did, we used trenchless,” Nyirenda said. “In this phase we were ap-proaching a more developed part of the city, and that meant we just didn’t have enough room to construct a 30-ft deep pipeline with traditional open cut.”

Digging DeepThe project was awarded to BT Construc-

tion of Henderson, Colo., an experienced trenchless contractor that performed micro-tunneling work on the Prairie Waters project. Of the roughly 5,000 ft of pipeline installed trenchlessly, about half was built using a 54-in. Akkerman TBM, and the other half was built using an Akkerman SL 51 (skinned up to 54-in.) microtunneling system. Both tun-neling machines installed 54-in. Permalok steel casing. Wyo-Ben provided the bentonite and additives, Derrick provided the slurry separation equipment, Microtunneling Inc. provided the intermediate jacking stations and auxiliary equipment.

Because of the soil variability, Aurora Wa-ter and with its consultant, CDM Smith, and the contractor, examined each manhole-to-manhole reach to determine optimum con-struction technique. “We made the determi-nation whether to use the TBM based on soil type,” said Brenden Tippets, Project Manager for BT Construction. “In areas where we had wet, running sands, we typically used slurry microtunneling. In areas where we had clay-stone, we used a TBM. Basically we evalu-


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If there is a challenging trenchless proj-ect in Hawaii, there’s a good chance that James Kwong will have played a role in its design. Kwong’s list of proj-

ects spans an impressive array of trench-less work in Hawaii – and across the globe.

His trenchless resume includes design on the Nimitz Highway Reconstructed Sewer Project (Trenchless Technology Project of the Year for New Installation in 2001) and Fort Kamehameha WWTP Ocean Outfall Extension-Microtunneling Segment (Trenchless Technology Project of the Year for New Installation Runner-Up in 2003) … and that’s just for starters.

His most recent work includes the Beachwalk Force Main project in Hono-lulu. This recently completed microtunnel-ing project marked the first time a curved drive was designed in the United States, and marks the longest curved drive and the first double-curve drive completed in the United States. The curved portion of the project was completed in October 2012.

But as an engineer, Kwong isn’t focused on setting records or pushing new tech-nologies. He is focused on building proj-ects efficiently and economically while meeting the needs of his clients. In his case, however, several of his projects had unique needs that have resulted in expanding the horizons of trenchless construction.

For his work, Kwong, principal of Yogi Kwong Engineers LLC in Honolulu, is the recipient of the Microtunneling Achieve-ment Award for Engineering Excellence. The award will be given at the Colorado School of Mines Microtunneling Short Course, Feb. 12-14, 2013, in Golden, Colo.

“James has been the go to guy on the Hawaiian Islands working on his second decade in the business,” said Tim Coss, president of Microtunneling Inc. and Mi-crotunneling Short Course director. “He has been involved in highly complex projects where pushing the envelope seems a routine matter. While mainland microtunneling projects remain very scarce, Hawaii’s huge appetite and James steady hand make it look so easy.”

BackgroundKwong was born and raised in Hong

Kong, which at that time was still a Brit-ish colony. As was customary, he went to England for advanced studies in 1973, earning a bachelor’s degree in geology from Queen Mary College at the Univer-sity of London. From there he went on to earn a master’s degree through complet-ing a course in engineering geology and geotechnics at the University of Leeds, which gave him an initial background in soil mechanics and rock mechanics.

Kwong continued his studies by earn-ing his Ph.D. on part-time basis while working for Maunsell Consultants Asia. Working under the tutelage of Dr. John Endicott, Kwong earned field experience while working on his thesis related to the engineering geology and geotechnical properties of weathered rock and slope stability. Included in his projects for Maun-sell (now part of Aecom) was a highway tunnel routing feasibility project in his na-tive Hong Kong.

After settling in Canada, Kwong served on a number of projects involving land-slide evaluation in North America and

Asia. Eventually, his attendance of a con-ference in Hawaii provided the twist of fate that expanded his career path to-ward the underground.

“At that time I met with the owner of a firm (Geolabs) that wanted me to join them in Hawaii … and he would usually call in the middle of the Canadian win-ter,” Kwong said. “Eventually they were looking for someone to help with a sew-er tunnel investigation, and I couldn’t pass up the opportunity.”

The real kicker for the deal was the fact that Kwong would be working alongside Dr. Ed Cording, longtime professor at the University of Illinois and among the world’s preeminent geotechnical engineers, and Dr. Jim Mahar, a University of Illinois prod-uct who has forged his own legacy in the field of geotechnical engineering.

“I wanted to learn from those two very good tunnel engineers, so I made the move to Honolulu,” Kwong said. “It turned out to be a blessing, and I learned a lot from them. I was very fortunate to have very good mentors early in my career.”

The project, the Makiki to Palolo Sewer Relief Project Increment 2, involved tun-neling in volcanic deposits with marine

Microtunneling Achievement Award:James Kwong, P.E.,Yogi Kwong Engineers

James Kwong of Yogi Kwong Engineers LLC will receive the Microtunneling Achievement Award for Engineering Excellence at the Colorado School of

Mines’ Microtunneling Short Course, Feb. 12-14, 2013, in Golden, Colo.

By Jim Rush

U191_20-21.indd 20 11/1/2012 10:36:28 AM


sediments laced with boulders, corals, sands and gravels – a geologic potpourri that would test the meddle of any under-ground engineer. “The geology was ex-tremely complex and it was a very good learning experience – both in terms of investigation and in developing a geotech-nical baseline report,” Kwong said.

Kwong, Cording and Mahar presented a paper on that project – “Tunneling In-vestigation in a Highly Complex. Marine-Volcanic Sequence, Honolulu, Hawaii” – at the fifth International Symposium on Tun-neling in London in 1988. That conference also turned out to be fateful for Kwong.

“It was there that I first saw a microtun-neling system – an Iseki – and saw pre-sentations about projects that had been done,” Kwong said. “I saw that this system had potential in Honolulu because of the high groundwater table, complex ground conditions and congested utility corridor.”

Microtunneling in HawaiiIt wasn’t until the 1990s that micro-

tunneling made its way to Hawaii, with Westcon among the first to complete a project as part of a runway crossing in Honolulu. Frank Coluccio Construction Co. completed one of the first major mi-crotunneling projects in Hawaii as part of a value engineering proposal shortly thereafter. One of the first major projects designed as a microtunnel was the Nim-itz Highway Reconstructed Sewer Proj-ect in Honolulu, designed by Woodward Clyde Consultants (now URS).

The design of the $21 million project be-gan in 1996 with construction completed in May 2001. The project involved 7,145 ft of 48-in. microtunneling through complex geology, including fill beyond the city’s original shoreline, within a dense urban environment and amid a maze of utilities. Contaminated soils, work below the water table and traffic mitigation issues made this project an ideal candidate for microtunnel-ing. The project was awarded the Trench-less Technology Project of the Year for New Installation in 2001. “One of the key chal-lenges for that project was utilities we dealt with,” Kwong said. “Additionally we had to work at night to avoid traffic, and limiting construction noise was also an issue.”

Soon after that project showed the merits of microtunneling, another proj-ect pushed the boundaries even further. In 2003, Frank Coluccio Construction Co. completed the Fort Kamehameha WWTP Ocean Outfall Extension for the U.S. Navy,

which earned Trenchless Technology Proj-ect of the Year for New Installation Run-ner-Up distinction in 2003.

The project was designed to lengthen an existing outfall near the entrance of Pearl Harbor, and necessitated the con-struction of a jacking pit in the open ocean. “A lot of people said that project could not be built,” said Kwong, who was involved in the microtunneling design. “We had to persuade the Navy that the method was proven and could work.”

Another challenge to the project was the geology. “The alignment passed un-der a protected reef with soft compress-ible soils, and we were not permitted to perform ground improvement due to en-vironmental concerns,” he said.

The most recent project to keep Hawaii on the forefront of the microtunneling in-dustry is the Beachwalk WWPS to Ala Mo-ana Park project in Honolulu. The project involved five 72-in. drives totaling 5,800 lf, including the first ‘s’ curve microtunnel-ing completed to date in the United States.

A combination of environmental fac-tors and existing obstacles led to the de-sign of the ‘s’ curve. “We were building the pipeline around a historic canal and pro-tected trees that would have made it very difficult to get environmental approval,” Kwong said. “We also had to deal with two bridges, a section of very narrow ease-ment and two major entrances to Waikiki. Since we couldn’t sink a shaft in the canal or take the bridges out of service, the only way to build it was with a curved drive.”

Kwong said that the contractor, Frank Coluccion Construction Co., was equipped with a state-of-the-art Rasa ma-chine that provided the requisite power, as well as interjack stations and a lubrica-tion system for the outside of the pipe string to keep jacking forces manageable. The project was the second curved drive completed in the United States, and could open the door as owners and engineers see the method as proven. “Straight drives are preferable,” he said. “But curved drives can be done if there are no other options.”

Forging AheadKwong says that for microtunneling to

increase in market share, it must become more cost competitive with other meth-ods. That can include reducing the number of shafts (by using curved drives or longer drives) and improving efficiency in survey-ing that slow production. “There is good po-tential for combining some of the available

concepts and technologies to make micro-tunneling even more cost effective,” he said.

One improvement in the market he has seen is in the equipment. Although some of the machines that were introduced 20 years ago are still active – and effective – new machines offer increased power and reliability. Case in point: the Rasa ma-chine for the final drive of the Beachwalk project powered through an unexpected zone of basaltic cobbles. “The machine ran thought part of a buried stream but was able to go through the rock with-out loss of production,” Kwong said. “If we had been stuck under the canal, that would have been a show-stopper.”

As for other owners, Kwong says it is important to pick a qualified team to lead a microtunneling project, including the designer, construction manager and con-tractor. “This is very sophisticated work and you need people to make sure every-thing is set up,” Kwong said. “You need to put a lot of thought into feasibility and design phase, as well as bid documents and GBR. It is a small cost upfront com-pared to what can happen if something goes wrong in construction.”

Jim Rush is editor of Trenchless Technology and TBM: Tunnel Business Magazine.

Fort Kamehameha WWTP Ocean Outfall Extension for the U.S.

Navy was designed to lengthen an existing outfall near the

entrance of Pearl Harbor, and necessitated the construction of a jacking pit in the open ocean.

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Project WIN (Waterway Im-provements Now), is part of Louisville-Jefferson County Metropolitan Sewer District’s

(MSD) response to a federal consent decree to improve its sewer system and reduce overflows into local wa-terways. The $850 million program is well under way and on track to meet its 2024 deadline.

As part of the program, MSD recently built the Shively Interceptor, which in-volved building a gravity-flow sewer to replace an aging forcemain. The force-main tied into five undersized pump stations that created bottlenecks with-in the system. Additionally, the pump stations were subject to mechanical failures and power outages that would contribute to overflows.

To build the new interceptor, MSD turned to pilot tube microtunneling,

which proved to be a win for WIN as it allowed the old main to be replaced with the least amount of impact on resi-dents. Qk4 provided design services for MSD on the project.

In June 2010, MSD awarded a con-tract to MAC Construction for $10.5 million to build approximately 21,000 lf of new interceptor and decommission the five pump stations. About half of the pipeline length was designed to be built using the pilot tube microtunnel-ing method (also referred to as guided boring method). This part of the project was subcontracted to trenchless spe-cialist contractor Midwest Mole from Indianapolis. Midwest Mole started the project in November 2010 and finished in April 2012.

“Open-cut was considered, but at the depths and soil conditions for this project, it would have necessitated full

road/right-of-way reconstruction, as well access problems for homeowners,” said Greg Powell, P.E., MSD’s construction engineer.

Although the district had limited ex-perience with microtunneling, it proved to be the best fit to deal with the issues of the depth of the interceptor, high water table, sandy soils and densely populated residential neighborhoods. The pilot tube microtunneling portion of the contract involved the installation of 10,678 lf of vitrified clay pipe (VCP) of various sizes, including 4,437 ft of 15-in. VCP, 4,280 lf of 18-in. VCP, 733 lf of 21-in. VCP and 1,228 ft of 27-in. VCP. The project is among the believed to be the third-largest pilot tube project complet-ed in the United States.

The trenchless crossings required the construction of two 12-ft diameter secant pile shafts, one 14-ft square inter-

Pilot Tube Microtunneling a WIN in KentuckyMassive Project Helps Upgrade Sewer System By Jim Rush

The Shively Interceptor project included more than 10,000 ft of pilot tube microtunneling.

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nally braced sheet pile cell, and thirty-four 9-ft diameter shafts ranging from 17 to 35 ft deep. The soil conditions consist-ed of loose, medium dense, coarse sands below the water table and to loose, fine sand above the water table.

Because the new interceptor was gravity flow and needed to tie in to two existing points within the system, a grade change of less than 13 vertical ft over the entire alignment was required. This flat grade meant that a precision in-stallation method like pilot tube micro-tunneling was needed.

“With gravity sewers, typically the more slope you have, the better,” said Joe Butor, Vice President of Engineering for Midwest Mole. “This project was so flat it did not meet 10 States Standards and required special approval.”

How It WorksPilot tube microtunneling can be lik-

ened to a hybrid of microtunneling, di-rectional drilling and auger boring. It in-corporates the laser guided accuracy of microtunneling, the steering mechanism of a directional drill, and a spoil removal system of an auger boring machine.

Like conventional microtunneling, a jacking shaft and reception shaft must be constructed for pilot tube tunnel-ing. Once the jacking frame is aligned using standard survey techniques, the operator then begins the installation of the 1-m long pilot tube sections. The pi-lot tube, about 4 in. OD for the Shively project, is basically a hollow tube with a slant-faced steering head, like that of a directional drill.

The head is equipped with a lighted target that, together with a theodolite calibrated for the desired line and grade in the jacking shaft, provide steering with an accuracy of within 0.1 in. The operator continually steers the pilot tube into the crosshairs of the target until reaching the reception pit. The in-stallation of the pilot tube involves no excavation; soils around the pilot tube are displaced. Bentonite can be added as each section of pilot tube passes through a seal at the jacking shaft.

Upon completion of the pilot tube, a hole-enlargement casing with auger is attached to the end of the pilot string. As each 1-m long segment of casing is jacked in, a section of pilot tube is pushed out into the reception shaft. Af-ter the casing has been jacked into place

and the spoil removed, sections of car-rier pipe are jacked in and the casing re-moved. Following the installation of the pilot tube, Midwest Mole installed 11-in. auger casings to enlarge the hole. The final step was to install product pipe, which was jacked into place behind a cuttinghead that is sized based on the diameter of the pipe installed. In this case, crews Akkerman Powered Cutting Heads to install the product pipe.

Getting the Job DoneFor the Shively project, MAC Construc-

tion subbed out construction of the drilled shafts and secant pile shafts to ABE Enterprises. In advance of tunneling, ABE completed the shafts, which were then covered them with road plates round-abouts constructed to maintain traffic flow in the largely residential work area.

For tunneling, Midwest Mole used an Akkerman 4812 and Akkerman 308 de-pending on the diameter and required thrust. Additional equipment included a Vermeer mud mixing plant and benton-ite and additives from Wyo-Ben. Can Clay was the VCP supplier.

Ground conditions consisted of loose, medium-grained sand below the watertable, and loose, fine-grained sands above the wa-tertable. In areas below the watertable, Mid-west Mole installed PVC drain pipes into the shaft beneath the access area, and de-watered the pit using submersible pumps.

Since sands are more problematic than cohesive soils, the bentonite pro-gram became all the more important in building the project, Butor said.

“Most people are aware that it is im-portant to have a bentonite program, but in order for it to be successful, you need a detailed plan: what you are mixing, how you are mixing it, at what ratios, how you are injecting it,” Butor said. “You also need to be monitoring what you are injecting and making adjustments as needed. It is also important to make sure that the crew understands what needs to be done and assign responsibilities.”

In the end, pilot tube microtunneling proved to be a good choice for the con-ditions. “The overall performance was excellent,” Powell said. “For the length of runs, soil conditions and relatively flat gradients, having excellent grade control was imperative and the pilot tube meth-od provided that important control for the constraints we were dealing with.”

Finally, teamwork played a big role in the successful completion of the proj-ect. “With two crews running for over 16 months, the pipe supplier (Can Clay), equipment manufacturer (Akkerman) and project team (MSD, Midwest Mole, MAC) had to tackle this monumental undertak-ing as a team to ensure success,” Butor said.

Jim Rush is editor of Trenchless Technology and TBM: Tunnel Business Magazine.

The depth of the interceptor would have necessitated

closing roads in the residential project area if constructed

with open-cut methods.

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Modern trenchless technology enables pipelines to be built over large distances, with a reduced number of shafts,

low risk of settlement and minimum impact on the environment. Tunneling equipment manufacturer Herrenknecht, which has more than 25 years of expe-rience worldwide in the areas of pipe jacking and segmental lining tunnels, has developed two innovative methods based on established microtunneling technology for the pipeline and mining industry: Direct Pipe and Boxhole drill-ing technology.

Direct Pipe for Pipeline Installation

The Direct Pipe method has been de-signed for trenchless installation of pre-fabricated steel pipelines. It combines microtunneling technology with newly developed thruster technology, the so-called Pipe Thruster. Direct Pipe incor-porates the advantages of microtunnel-ing, which reduces risk of frack outs in difficult ground conditions compared to horizontal directional drilling (HDD). The Pipe Thruster generates the thrust for the operation similar to the jacking frame in a standard pipe jacking opera-tion. It originally has been developed as pipe assist tool for the pullback of the pipe in a standard HDD operation.

The Pipe Thruster embraces the pre-fabricated and laid out pipeline and pushes it into the ground in strokes of 5 m each. The requisite bore hole is ex-

cavated by a slurry microtunneling ma-chine (AVN), which is mounted at the front of the pipeline (Figure 1). Prior to launching the machine, it is positioned at the requisite access angle in front of the launch seal. The pipeline is welded to the conical rear section of the ma-chine and mounted on rollers behind the launch pit. The clamping unit of the Pipe Thruster embraces the pipeline and thrusts it into the ground along with the machine. The current maximum pipe-line diameter that can be clamped is 60 in. OD (1,524 mm). The forces to be an-chored depend on the pipeline access angle and the maximum thrust force to be applied.

Installation of Coated Gas Pipelines

Since 2007 more than 18 pipeline projects have been successfully com-pleted in Europe and the United States using the Direct Pipe method. After passing elaborate quality load tests conducted on test pipes with various coating materials to ensure that the Pipe Thruster does not pose a risk of damaging the coating of the pipes, ap-proval was given from a Dutch-German gas supplier for utilizing the Direct Pipe method for pipeline installation. A to-tal of six crossings were then realized in the Netherlands – between 360 and 1,400 m in length – crossing rivers, rail-ways lines and archaeological sites. The project was part of the approximately 500-km long North-South Route of 48-

in. OD (1,220 mm) pipe for transport-ing gas throughout the Netherlands. The most challenging crossing was a 1,400-m long section, which represents the longest pipeline ever installed by Direct Pipe to date. In a geology of sand, gravel and clay two Herrenknecht Pipe Thrust-ers HK500PT pushed the 48-in. pipeline into the ground with a maximum daily advance rate of 230 m. In the meantime, Direct Pipe has proven itself in several gas pipeline projects, including the crossing of I-70 in Florida (August 2010) and a recent conductor pipe installation in Jersey City, N.J. In addition to Europe and The United States, installations are planned for Canada and Thailand.

Allowing fast installation rates, the Di-rect Pipe method is an alternative to HDD and standard microtunneling: The high installation reliability in difficult (perme-able) soils – compared to HDD – as well as the economic advantage over conven-tional pipe jacking translates into consid-erable competitiveness of this method.

Boxhole Boring Machine: New Technology for Creating Slot Holes

A large number of vertical or inclined small-diameter slot holes need to be excavated in many underground mines worldwide. To this aim, Herrenknecht has developed and built a new Boxhole Boring Machine (BBM). This concept is also based on the well-proven pipe jack-ing technology, targeting a high safety standard, minimal drift dimension, high

Taking Microtunneling to New HeightsRecent Innovations Expand Microtunneling Technology into Pipeline and Mining Sectors By Werner Burger, Diana Pfeff, Benjamin Künstle and Dr. Gerhard Lang

FIGURE 1Direct Pipe river crossing, view from shaft with Pipe Thruster.

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mobility and flexibility. Higher produc-tion rates can be achieved using the BBM, resulting in significant time savings compared to conventional drill-and-blast excavations. The faster and more safely slot holes can be constructed, the earlier the actual production in the mine can start or be continued.

The BBM was developed for construc-tion of vertical and inclined slot holes (± 30° from vertical) with a diameter of up to 1.5 m and a length of (maximum) 60 m in hard rock formations. During develop-ment, the focus was mainly on increased safety due to a remotely operated ma-chine, higher productivity and optimum machine mobility. Quick relocation of the BBM and minimum space requirements were also key factors of the design.

For transporting the BBM, a compact crawler unit provides a high degree of flexibility in confined underground con-ditions. A modular design allows opera-tion even in tight spatial conditions. The jacking frame with the boring unit, cable drum and power pack can be positioned separately (Figure 2).

In the production area, the jacking frame is adjusted to its correct position and aligned toward the requisite boring angle. To stabilize the system and trans-fer the operational thrust and torque loads into the rock, the jacking frame is braced against the floor and the back. The thrust forces are transferred from the jacking frame to the machine cutter-head via steel thrust pipes similar to hor-izontal pipe jacking operation (Figure 3). The cutterhead is designed for hard rock geologies of 180 MPa (26,000 psi) and more and fitted with multiple-row carbide cutters. Different cutterhead

variants equipped with various cutter tools can be used as an alternative.

A funnel directs the excavated cut-tings through the boring machine and the thrust pipes to the material chute on the jacking frame where they slide into a skip for transporting.

After each meter of exaction, the op-eration process will be stopped tempo-rarily. A clamping system holds the pipe string and the boring machine in place in order to install and connect the next thrust pipe. Once the required boring distance been reached, the boring unit is retracted. The thrust pipes are removed one by one until the boring unit is com-pletely pulled back. The BBM is fully remote-controlled, also the crawler for relocating the BBM is remote-controlled, so the operator remains in a safe work-ing area during boring and transport.

BBM Application in Australia

Mancala Pty Ltd., providing special-ized services for the Australian mining and construction industry, ordered a Herrenknecht BBM1100 in October 2010. In early 2011, the prototype was tested in the small Clara Mine close to the Herrenknecht factory in southern Germany. Vertical and inclined test slot holes with a diameter of 1.1 m and a length of 9 m were successfully drilled and showed that production rates of 9 m within 5 hours could be achieved in challenging rock conditions with a UCS of up to 250 MPa (36,000 psi). During this period, valuable data was collected in order to optimize operational param-eters and handling details.

After commissioning in Australia in September 2011, the BBM was transport-ed to the Cadia East Underground Mine, located 260 km (160 miles) west of Syd-ney. Gold and copper deposits cover an area 2.5 km in length, 600 m wide and up to 1.9 km deep. During the test run three vertical operations with a length of approximately 18 m were success-fully bored in fractured and blocky rock formations with a UCS of up to 200 MPa (29,000 psi). From November 2011 to June 2012, the Herrenknecht BBM1100 was in operation at a depth of approxi-mately 1,000 m at the production level for developing the draw points, making it a key component in development of the mine. It realized more than 40 slot holes with an average length of 16.5 m and an average advance rate of 1.5 m/h. The op-erator succeeded in realizing up to three slot holes a week in single-shift operation (including setup, boring and transport preparation). Now the BBM1100 is em-ployed in the Broken Hill Mine in New South Wales for constructing vertical and inclined slot holes. Because of the suc-cessful results and upcoming mine inter-est the customer already ordered two fur-ther Herrenknecht BBMs, which will be commissioned in early 2013.

Werner Burger is chief engineer, Diana Pfeff is product manager for Direct Pipe, Benjamin Künstle is a member of the mining applications team, and Dr. Gerhard Lang is business development manager for Herrenknecht AG, based in Schwanua, Germany.


FIGURE 2The modular design of the Boxhole Boring Machine allows operation even in tight spatial conditions.

FIGURE 3BBM system overview: vertical slot hole construction based on the horizontal pipe jacking operation.

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Highlighted by recent major projects in Massachusetts, the New England region has recently seen an increase

in installations of centrifugally cast, fiberglass-reinforced polymer mortar (CCFRPM) pipe for microtunneling and pilot tube microtunneling projects. One project involved pilot tube auger boring under a river to install 430 ft of 36-in. diameter CCFRPM pipe to contain elec-trical conduits, while another project consisted of microtunneling four runs of 48- and 57-in. diameter CCFRPM pipe at distances up to 837 ft.

Pilot Tube Tunneling in Cambridge

Construction of the $14 million Cam-bridge Park Drive Drainage Improve-

ments project eliminated a combined sewer outfall near the public drinking water supply in Cambridge, Mass., mini-mized flooding in West Cambridge, and reduced the discharge of pollutants into the Little River. Part of the project in-volved relocating five utilities in order to build a wetland basin. The utilities cross-ing the Little River needed replacement using a suitable trenchless method, ac-cording to a technical paper by John J. Struzziery, P.E., of the engineering firm of Kleinfelder, Cambridge, and Nick Strater, P.G., of Brierly Associates LLC, Manchester, N.H.

Horizontal directional drilling (HDD) was originally designed and bid as the preferred means of relocating the utili-ties for the river crossing. After the bid, however, the proposed length of the

HDD bore could not be accommodated due to adjacent property restrictions that prevented the city from obtaining the needed rights of entry.

After a detailed review of alternative trenchless methods, pilot-tube guided auger boring (PTAB) was selected. The five utility crossings ranged in diam-eter from 4 to 36 in. The most challeng-ing reach involved a 430-ft crossing for electrical conduit with 36-in. diameter HOBAS pipe – a feat which people con-nected with the project believe set a new world record for the PTAB method.

The general contractor, P. Gioioso & Sons, Inc., Hyde Park, Mass., subcontract-ed the trenchless crossings to Icon Tun-nel Systems, East Brunswick, N.J.

The PTAB method is a multi-stage pro-cess that begins with jacking a series of


Critical Mass.New England Sees an Increase in the Use of Fiberglass Pipe

U191_26-27.indd 26 11/1/2012 10:37:27 AM


pilot tube rods through the ground from a launching pit toward a receiving pit. The pilot tube rods and tube head sim-ply displace the soil so no soil removal is required until later. “For guidance, the 5.5-in. diameter pilot tube uses a the-odolite camera that is mounted on the ground, or on the shaft along with the jacking machine,” said David Crandall, vice president of Icon.

Once the pilot tube reaches the re-ceiving pit, the line and grade for the bore are established. The next step is to jack in 16.5-in. temporary augers and casings. “Your pilot rods are removed as you’re jacking,” said Crandall. “As the casings and augers advance through the ground simultaneously, the pilot rods are removed and taken out through the re-ception pit until the casings reach the reception pit. Now the 16.5-in. casings and augers are in the ground following the path of the line and grade.”

On the Cambridge project, Icon next attached a larger reaming extension kit to the pipe string in the jacking pit. A direct hydraulic drive motor was lo-cated inside the extension to excavate the overcut. The overcut of dirt was brought in through the extension, and then pushed back through the casings toward the reception pit.

The 36-in. HOBAS pipe fits behind the extension using a jacking ring. “The only things inside the pipe at that point were the hydraulic lines, the water lines or bentonite lines that go directly to the back of the extension,” said Crandall. “At this point you’re just loading in your HO-BAS pipe and pushing it forward. As the extension advances through the ground, the casings are removed in the recep-tion pit. When your HOBAS pipe reaches the other side, your job is done.”

According to John Struzziery, se-nior program manager for Kleinfelder, CCFRPM pipe was specified for this project because of its thermal proper-ties – it does not conduct heat well. Six high-voltage electrical conduits were grouted inside the HOBAS pipe. “The HOBAS pipe provides insulation around the electrical conduits, so that heat doesn’t escape beyond the casing,” said Struzziery.

Largest Public Works Project for Brookline

In Brookline, Mass., CCFRPM pipe was used on the Lower Beacon Street Sewer

Separation Phase II project. According to BETA Group’s website, the Town of Brookline engaged BETA to oversee and manage the construction of this $18.1 million, two-phase sewer separation project located in the easternmost ur-banized areas of the town. The majority of the project is located along the con-gested Beacon Street corridor and ad-joining neighborhood streets. This is the largest public works project ever com-missioned by the town and is a joint and cooperative effort between the Town of Brookline and the Massachusetts Water Resources Authority (MWRA) as part of their Long-Term Combined Sewer Over-flow (CSO) Control Plan.

The primary purpose of the project is to separate sanitary flows from an exist-ing 110-year-old combined brick sewer system by installing new large-diameter sewers that connect directly into the MWRA facilities. The existing combined sewer was then converted to a dedicat-ed conduit for transporting storm drain-age to the Charles River. Project benefits will reduce the amount of storm-related flows entering the MWRA system, there-by reducing transport and treatment costs as well as MWRA CSO discharges to the Charles River.

Only HOBAS Pipe was specified for the project and was utilized for the six microtunneling runs on the project. P. Gioioso & Sons Inc. was again the gener-al contractor and subcontracted the mi-crotunneling to Michels Corp., Browns-ville, Wis.

The tunnel varied in depth to the pipe invert from 20 to 35 ft. Michels used two Akkerman microtunneling machines to bore through varied ground conditions including boulders, gravel, sand, silt and clay. The machines jacked 10-ft sections of 48- and 57-in. diameter Hobas pipe into place. A 57-in. diameter pipe with an allowable capacity of 425 U.S. tons at a specified factor of safety of three was installed on a 498-ft run, while the 48-in. diameter pipe with an allowable capac-ity of 350 U.S. tons at a specified safety factor of three was installed in three runs of 837, 639 and 529 ft.

Principals involved in the project agreed that there were no significant problems with the microtunneling and the HOBAS pipe went into place just as expected.

Acceptance and use of HOBAS CCFRPM pipe has grown in the New England region, not only for microtun-neling, but also for sliplining, direct bury and above-ground projects. With the varied installation methods, corrosion resistance and long service life, more projects are likely on the horizon.

This article was contributed by HOBAS Pipe USA.

The most challenging reach of the Cambridge Park Drive Drainage Improvements was a 430-foot-long crossing for

electrical conduit and utilized 36-inch diameter HOBAS pipe.

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ALABAMAThomasvilleRaw Water Intake Vadnais Corp.

Vadnais Corp. completed the Raw Water Intake project in June 2012. The project was for the City of Thomasville. Permalok steel casing was utilized. The project con-sisted of one 30-in. diameter drive of 255 lf. The jacking shaft was 85 ft deep. There was a water retrieval in the Alabama River, which used a crane, a barge and divers in order to locate and retrieve the MTBM as it came into the river.

CALIFORNIACoronaSanta Ana River Interceptor (SARI) James W. Fowler Co.

James W. Fowler Co. is completing the San-ta Ana River Interceptor (SARI) Relocation – SARI Mainline (Including Metering Station) Project for Orange County’s flood control division. Crews will use a Herrenknecht AVN 2000D for this $8.8 million project.

The project includes: 4,000 ft of 101.5-in. OD microtunnel done in four drives with installation of 2,900 ft of 84-in. ID reinforced concrete pipe and 1,100 ft of 99.5-in. ID steel casing. Drive lengths are Drive 1 – 1,567 ft; Drive 2 – 622 ft; Drive 3 – 1,089 ft; Drive 4 – 650 ft. Drive 1 is a compound curve and will be the first uti-lization of the Jackcontrol hydraulic joint and real-time monitoring system in North America. Drive 2 will also have a curve uti-lizing the Jackcontrol hydraulic joint and real-time monitoring system. Mixed face conditions with cobbles and boulders be-low the groundwater table are expected. W.A. Rasic Construction is the general contractor. Tetra Tech is the engineer. Tun-neling on the first drive was expected to begin by mid-November.

La MiradaI-5 Widening Relocation Vadnais Corp.

Vadnais Corp. completed the I-5 Widen-ing Relocation for Chevron Pipeline Co. in March 2012. The project consisted of two side-by-side 36-in. steel casing tunnels 385 ft long each. The tunnels were used to relocate fuel and oil pipelines. Vadnais used an Iseki TC600. The ground conditions were a mix-ture of clays and silts. The project was con-structed in ground water at a depth of 25 ft.

Los AngelesPenmar Water Quality Improvement Project - Phase 1 Vadnais Corp.

Vadnais Corp. completed this project for the City of Los Angeles in November

2011. The ground conditions consisted mainly of sand and silt. Vadnais used an Iseki TCC800 to push 148 lf of 42-in. Per-malok steel casing.

VistaWatson Way Upsizing and RealignmentJames W. Fowler Co.

James W. Fowler is preparing for this $5.7 million project for the Buena Sanita-tion District. Crews will use a Soltau RVS 600 to install 2,580 ft of 53-in. OD micro-tunnel done in three drives with installa-tion of 42-in. ID reinforced concrete pipe. Drives lengths are Drive 1 - 466 ft, Drive 2 - 1,736 ft and Drive 378 ft. Drive 2 in-cludes a curve. Ground conditions will be mixed face conditions with granitic mate-rial above the groundwater table. The en-gineer is Psomas. Tunneling is scheduled to begin in December 2012 and the proj-ect will be completed in July 2013.

Santa MonicaSanta Monica Low Flow Diversion Upgrades Package 3 Vadnais Corp.

Vadnais Corp. completed this project in May 2012. Vadnais used a Soltau RVS 600 to install Permalok steel casing. The drive was 60 lf with a depth of approximately 25 ft in sand and clay conditions.

COLORADODenverCentral Park Boulevard ConduitVadnais Corp.

Vadnais Corp. completed the Conduit 151 Central Park Boulevard from Smith Road to I-70 for Denver Water in May 2012. The project consisted of two drives totaling 1,231 lf. The first drive was 906 lf under I-70; the second drive was 325 lf under UPPR. Permalok steel casing was used at a depth of approximately 20-25 ft. Vadnais Corp. used a Herrenknecht AVN 800 to complete the project.

DenverDIA ImprovementsVadnais Corp.

Vadnais Corp. is constructing the Den-ver International Airport STRP EWP B Storm Sewer for Kiewit Building Group Inc. The engineer is Jviation of Denver. It is a single tunnel drive of 1,629 lf of 66-in. ID RCP. Two intermediate jacking sta-tions will be utilized on this drive. The launch shaft is approximately 18 ft deep and the reception shaft is approximately 52 ft deep. Tunneling is through stiff to very stiff sandy clay. Groundwater is not anticipated. The work is being performed adjacent to the DIA Main Terminal be-

neath heavily trafficked roads. Tunneling activities occur nearby critical FAA com-munication cables and an active 102-in. ID Storm Sewer. The MTBM deployed is a Herrenknecht AVN1500TB with an 82.5-in. OD. Bid value of $4,400,000. The tun-nel work will be completed by Dec. 15, 2012.

CONNECTICUTHartfordGrandby Street Area Sewer Separation Project 2/5Bradshaw Construction Corp.

Bradshaw Construction Corp. recently completed 2,550 ft of pipe jacking as part of a sewer separation project. The project includes the installation of 910 ft of 60-in. RCP and 1,500 ft of 48-in. RCP via microtun-neling, and 145 ft of 42-in. RCP with a con-ventional TBM. The work was performed under Granby Street in northwest Hartford, between Burlington Street and Branford Street. The soil conditions consisted primar-ily of extremely soft silts and clays below the ground water table. Information: Doug Piper, [email protected]

FLORIDAHialeahNW 170th Street 36-in. Water MainBradshaw Construction Corp.

Bradshaw Construction Corp. has suc-cessfully completed construction of a 520-lf tunnel under I-75 along NW 170th St. The tunnel was constructed by micro-tunnel below the water table through limestone. The installed 52.5-in. steel cas-ing was threaded with a 36-in. DIP as the final product. Information: Michael Gib-son, [email protected].

JacksonvilleRoyal Lakes Housing ProjectHuxted Tunneling

Huxted Tunneling completed Jackson-ville’s first microtunneling project as part of 10,000-ft new force main as part of the Royal Lakes Housing Community expan-sion. Huxted used its Iseki Unclemole to drive 275 ft of 42-in. steel casing under SR 115. Mixed ground conditions included clays, silts, gravels, cobbles and boulders. The owner is Jacksonville Electrical Au-thority (JEA). J.B. Coxwell Contracting was the general contractor.

MiamiMDC Thermal Plant Interconnection ProjectBradshaw Construction Corp.

Bradshaw Construction Corp. has be-gun construction on twin chilled water lines for Miami-Dade County and BGA

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Inc. This general contract includes ap-proximately 1,890 lf of 24-in. ductile iron chilled waterline, of which 840 lf will be in 30-in. steel casing installed in four microtunnels. The project also includes sitework, restoration and construction of a taxi stand. Information: Mike Wanhatalo, [email protected]

INDIANA IndianapolisCastleton Relief Sewer Project – Phase IBradshaw Construction Corp.

Bradshaw Construction Corp. has com-pleted construction of a 2,740-ft long relief sewer in Indianapolis. The pipeline consists of 42-in. RCP installed by pipe jacking, mined utilizing a microtunnel boring machine. The downstream tie-in was made in 71st Street at its intersec-tion with Crittenden Avenue. From there the tunnel continued north along Critten-den and then east below Riverwood Park, along the north side of Howland Ditch, concluding on the east side of the Key-stone Avenue bridge. Geologic conditions consist of sands below the groundwater table with cobbles and boulders. The proj-

ect also included the installation of six manholes and a tie-in to the existing sys-tem. This project was completed in May 2012. Information: Todd Brown, [email protected]

MARYLANDBaltimoreImprovements to Herring Run Interceptors – Phase ICruz Contractors LLC

Cruz is constructing the Improvements to Herring Run Interceptors – Phase I project for the City of Baltimore with a contract price of $11.7 million. The project will be carried out in two phas-es. Phase 1 consists of the installation of 4,120 lf of sanitary sewers ranging be-tween 8 and 54 in. Of the 4,120 lf, 2,500 lf is to be microtunneled. Work is about 50 percent complete.

White MarshI-95 Express Toll Lanes, MD 43 InterchangeBradshaw Construction Corp.

Bradshaw Construction Corp. recently completed 460 ft of pipe jacking as part

of the I-95/MD 43 interchange project. The project included the installation of 460 ft of 90-in. steel casing via microtun-neling for the 54-in. RCP carrier pipe that forms a portion of the White Marsh Run Interceptor. The work was performed un-der I-95 northeast of Baltimore. The soil conditions consisted primarily of clays, silts and sands below the ground water table. Information: Doug Piper, [email protected]

MASSACHUSETTSBrooklineLower Beacon Street Sewer Separation, Phase 2 Michels

The Lower Beacon Street Sewer Separa-tion, Phase 2 project is a sewer and storm drain separation project in Brookline. The $24 million project, funded by the Massachusetts Water Resource Author-ity (MWRA), included a total of 4,290 lf was installed with GBM and slurry MTBM microtunneling systems in 11 drives and 13 shafts (five jacking shafts, five receiv-ing shafts and three combination jacking and receiving shafts) that ranged from

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20-30 ft. below the street level. Michels used Akkerman MTBM SL 52.5 and SL 60 equipment systems for traditional slurry microtunneling runs. Encountered soil conditions included clay, sand, and silt of-ten with a high water table. The longest drive was 837 lf.

NEW JERSEYCarteretTurnpike Sanitary Sewer CrossingCruz Contractors LLC

Cruz Contractors LLC is building the $2.2 million Turnpike Sanitary Sewer Crossing project for the Borough of Cart-eret. The project generally consists of mi-crotunnel installation of approximately 760 lf of 30-in. sanitary sewer interceptor in a 48-in. casing under the New Jersey Turnpike, installation of approximately 155 lf of 8-, 21- and 30-in. gravity sewers in the adjacent area, and lining an exist-ing 24-in. sanitary sewer. Work is about 10 percent complete.

Weehawken18th Street Pumping Station CSO Force Main and OutfallCruz Contractors LLC

Cruz Contractors LLC is constructing the 18th Street Pumping Station CSO Force Main and Outfall with a contract price of $3.6 million. The work includes the installation of approximately 270 lf of 48-in. forcemain using open-cut exca-vation and approximately 290 lf of 48-in. forcemain to be installed in a 66-in. micro-tunneled casing. Work is about 50 percent complete.

NEW YORKNew YorkMTA CrossingsCruz Contractors LLC

Cruz Contractors LLC was hired by Tu-tor Perini to install 2,200 lf of 48-in. RCP by microtunneling for 15 crossings under the MTA railroad in Queens. This sub-contact is valued at $6.9 million. Work is about 50 percent complete.

Staten IslandRichmond Valley Road Sanitary and Storm SewersCruz Contractors LLC

This project for the City of New York Department of Design and Construction Division of Infrastructure involves the construction of 1,400 lf of 12-in. RCP sanitary sewer in direct-jacked 30-in. steel sleeve. The project consists of two drives of 800 lf and 600 lf with a maximum depth of 40 ft. Soil consists of silty sand. The project also includes one 900-ft drive

of 36-in. RCP sanitary sewer with a maxi-mum depth of 42 ft, also in silty sand. The overall contract value is $21,895,780 with microtunneling valued at $4,800,000. Cruz expects to start the project in Octo-ber and finish by mid-2014.

Staten IslandWoodrow Road Sanitary and Storm SewersCruz Contractors LLC

This project for the City of New York Department of Design and Construction Division of Infrastructure involves the construction of 1,800 lf 42-in. RCP sani-tary sewer in three drives of 600 lf each in clay/silty material at depths of up to 45 ft. Crews are using a Herrenknecht 1000. The total contract value is $11.9 million with microtunneling valued at $2.4 million. Cruz began the project in March and expect to be finished by June 2014. The project is currently 33 per-cent complete.

NORTH CAROLINARaleighCrabtree Basin Wastewater Conveyance Improvements – Phase 1Bradshaw Construction Corp.

Bradshaw Construction Corp. is start-ing construction on three tunnels totaling 660 ft by pipejacking 60- and 72-in. Ho-bas pipe behind microtunnel boring ma-chines. The tunnels cross under existing pipelines and roadways. Subsurface condi-tions range from hard granite to loose allu-vium below the water table. Information: Eric Eisold; [email protected].

OHIOAkronMassillon Road SewerMichels Tunneling

Michels Tunneling installed 42-in. and 48-in. sewer pipe for the City of Akron as part of the Massillon Road Sewer project. The project included seven 35-ft deep shafts and six tunnel runs totaling 4,253 ft — 1,328 ft of 48-in. tunnel and 2,925 ft of 42-in. tunnel. Tunnel runs ranged from 300 ft to more than 1,000 ft. The project is part of a major upgrade to the sanitary sewer system in Akron.

ClevelandEuclid Creek Tunnel Vadnais Corp.

Vadnais Corp. is working on the Euclid Creek Tunnel project for the Northeast Ohio Regional Sewer District. As of Oc-tober 2012, Vadnais Corp. has completed three 42-in. diameter drives of 629, 845 and 629 lf. Hobas pipe is installed using

a Herrenknecht AVN 800. In 2013, Vadnais Corp. will install approximately 237 lf of 72-in. Hobas pipe using a Soltau RVS 600.

RHODE ISLANDProvidenceWoonasquatucket CSO InterceptorSuper Excavators Inc.

Super Excavators Inc. is preparing to begin the microtunneling on the Woon-asquatucket CSO Interceptor Project (Contract No. 303.03C) for the Narragan-sett Bay Commission. Super Excavators is the microtunneling subcontractor for the general contractor, Barletta Heavy/Shank/Balfour Beatty JV.

Microtunneling consists of 3,980 lf of 72-in. diameter pipe, 2,072 lf of 60-in. di-ameter pipe, 1,540 lf of 54-in. diameter pipe, 3,350 lf of 48-in. diameter pipe, 788 lf of 42-in. diameter pipe, 120 lf of 36-in. di-ameter pipe and 608 lf of 30-in. diameter pipe. All the tunneling will be performed using Akkerman MTBMs of various size

Personnel on the project include: Proj-ect Supervisor: Brian Strane; Project Man-ager: Shawn Stockwell; Tunnel Superinten-dent: Nate Wiedmeyer.

The value of the microtunneling work is $14.8 million. Jacobs is the engineer for the project in association with CH2M HILL and GRA.

TEXASHoustonHillcroft Avenue WaterlineVadnais Corp.

Vadnais Corp. used a Soltau RVS 600 to complete a 42-in. waterline along Hillcroft Avenue for the City of Houston. The proj-ect involved the installation of 325 lf of 60-in. Permalok steel casing under High-way US 90A and the UPPR tracks. The ground conditions were mainly dense clay. The project was completed in Octo-ber 2012.

VIRGINIAFairfaxI-66 Sanitary Sewer CrossingBradshaw Construction Corp.

Bradshaw Construction Corp. is pre-paring to install 330 ft of 60-in. steel cas-ing and 18-in. sewer pipe as part of the I-66 Sanitary Sewer Crossing project. The casing will be installed by pipe jack-ing, mined utilizing a microtunnel bor-ing machine. The ground conditions are predominantly sand and silt below the ground water table; however, some rock will also likely be encountered. Work for this project began in early August 2012. Information: Elliott Bradshaw, [email protected].

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North American Microtunneling ProductsAKKERMAN MICROTUNNELING SYSTEMS

Akkerman microtunneling systems are a fusion of high productivity, dependability and accuracy for gravity flow pipelines requiring exact line and grade in poor soil conditions. Standard MTBMs are avail-able from 30- to 74-in. OD and can be fitted with increase kits to accommodate larger pipe diameters. Akkerman MTBMs feature a project-appropriate cutterhead for precise ground excavation. Akkerman control containers, the information center for all microtunneling functions, house the control console, motor controls for slurry pumps, MTBM drive motor and bulkhead panel. The Akkerman line of keyhole jacking frames allows customers to operate a high-capacity jacking frame out of a minimal launch shaft. Collectively, keyhole jacking frames operate out of a 16- to 24-ft shaft and feature 800 to 1,200 tons of thrust capacity at 8,000 psi.

EZEBREAK MICRO-BLASTERThe revolutionary Micro-Blaster IIx3 System allows users to break rock and concrete in almost any location

quickly and economically. Extremely portable, weighing only 20 lbs, the system requires only 5/16-in. diameter drilled holes 10- to 16-in. deep, further saving time and equipment costs. Utilizing proprietary cartridge tech-nology, the system is capable of breaking competent material from a few hundred to several thousand pounds. Used by builders, excavators, landscapers, rural landowners, rescue personnel and mine workers, Micro-Blaster Systems solve difficult demolition problems quickly and easily. Micro-Blaster systems are exempted from Cana-dian and U.S. Federal Blasting Regulations and do not require licensing in most locations. Available in single head versions for smaller projects.

HAYWARD BAKER GEOTECHNICAL CONSTRUCTIONHayward Baker, a North American leader in geotechnical construction and a member of the world-

wide Keller Group of companies, has decades of experience with the full range of geotechnical con-struction techniques to solve a variety of microtunneling issues. Jet grouting and soil mixing stabilize soft soils prior to tunneling. Jet grouting and soil mixing create tangent or secant pile shafts for tunnel access. Jet grouting, chemical grouting and cement grouting stabilize soils around break-ins and break-outs and control groundwater. Anchors, shotcrete and grouting techniques stabilize tunnel liners. Compaction grouting densifies loose soil under tunnel alignments, and helps relevel MTBMs. Fracture grouting, chemical grouting and compaction grouting control settlement of overlying structures dur-ing tunnel boring. Whatever the size of the project, Hayward Baker has the experience and technology to provide an innovative, robust and cost-effective solution.

HOBAS PIPE USA Hobas Pipe USA has been manufacturing centrifugally cast, fiberglass-reinforced, polymer mortar (CCFRPM) pipe

at its Houston plant since 1987, and recently expanded its diameter range. It now offers pipes ranging from 18 to 126 in. in diameter, with capabilities to produce even larger sizes. The expansion includes a 120-in. diameter that will be supplied to the City of Houston’s Northside Sewer Relief Tunnel, Area 5, which will be used to rehabilitate over a mile of existing 132-in. monolithic concrete. CCFRPM is inherently corrosion resistant and lasts 100 years or more. Applica-tions include storm and sanitary sewers, potable water, force mains, outfalls, industrial effluents and other corrosive environments. Hobas is ideal for virtually every installation method including open cut, sliplining, jacking, microtunnel-ing, two-pass tunnel, casing carrier and above ground. Hobas is ISO 9001 and 14001 certified and exceeds the product standards for sanitary sewer pipe.

MUNRO LTD. MICROTUNNELING PIPE Munro Ltd. now offers microtunneling pipe designed specifically to suit MTBMs and ground conditions.

The pipe is ideally suited as a tunnel liner or for direct conveyance of fluids. Pipes join together easily with gasketed joints. Pipes with lubrication ports can be provided to lubricate the overcut annulus during pipe drives. Once the tunnel is complete, the lubrication ports can be used to grout the annulus. Provide the in-ternal diameter and external diameter, jacking forces and loading conditions and Munro Ltd. will design the pipe to suit the application.

VERMEER AXIS BORING SYSTEMUnderground contractors now have a new option for the trenchless installation of critical grade water and

sewer lines. The AXIS guided boring system from Vermeer is a pit-launched, laser-guided tool to install 10- to 14-in. pipe. The system can achieve pinpoint, on-grade accuracy and has the ability to install pipe up to up to 350 ft in length, ideal for manhole-to-manhole applications. Spoil is removed from the cutterhead via a vacuum excavation system, thus keeping the pit clean. The system can either push or pull the product pipe into place, providing flex-ibility in the type of product installed. The AXIS system is made up of four main components — the power unit, rack, vacuum pump and vacuum tank. Various setup configurations can be used to adjust the machine’s footprint based on jobsite and transport characteristics.

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CONTRACTORSBradshaw Construction Corp. Lester M. Bradshaw, President Eric Eisold, Area Mgr. 173 West Liberty Rd.. Eldersburg, MD 21784 United States 410-970-8300 [email protected] www.bradshawcc.com Large Diameter Tunneling, Microtunneling, Pipe Jacking, Shafts, Tunneling-Large Diameter

BRH-Garver ConstructionPeck Boswell, President Phil Reed, VP Estimating 7600 S. Santa Fe, Bldg. A-1East Houston, TX [email protected]

BTrenchless9885 Emporia St. Henderson, CO 80640-8459303-286-0202www.BTrenchless.com

Carp-SecaStephen Leius77 Bloomfield Ave.Staten Island, NY [email protected]

Cruz Contractors LLC Dominic Pillari, Chief Project Mgr. 952 Holmdel Rd. Holmdel, NJ 07733 732-946-8400 [email protected] www.cruzcontractors.com Pipe Jacking, Microtunneling, Shafts, Pipe Jacking, Shafts

D’Agostini & Sons 15801 23 Mile Road Macomb, MI 48042 586-781-5800

ECIRoss Johnson, VP PO Box 7095 St. Paul, MN 55107657-298-9111 [email protected] www.eandci.com Grouting, Dewatering, Microtunneling, Shafts, Demolition

E E Cruz & Co. Inc.Edward Cruz 952 Holmdel Rd., Cruz PlazaHolmdel, NJ 07733732-946-9700www.eeccruz.com

EIC Associates 140 Mountain Ave., Suite 303 Springfield, NJ 07081 973-315-0200www.eicassociates.com

Frank Coluccio Construction Co. Don Bergman, Cheif Estimator Bill Austell, Senior Estimator/PM 9600 Martin Luther King Way South Seattle, WA 98118-5693 United States 206-722-5306 [email protected] www.coluccio.com Grouting, Shafts, Pipe Jacking, Microtunneling, Dewatering, Auger Boring, Relining, Tunnel Linings, Tunnel Support, Jet Grouting, Large Diameter Tunneling, Drilling, Shafts, Microtunneling, Pipe Jacking , Tunneling-Large Diameter

Horizontal Boring & Tunneling Co. Brent L. Moore, President505 S. River Ave. PO Box 429 Exeter, NE 68351 United States 402-266-5347 [email protected] Auger Boring , Tunneling-Large Diameter, Pipe Jacking, Microtunneling, Auger Boring, Large Diameter Tunneling, Drilling, Microtunneling, Pipe Jacking , Grouting, Grouting

Huxted TunnelingSteve Caneen, President3208 17th St.East Palmetto, FL 34221941-722-6613scaneen@huxtedtunneling.comwww.huxtedtunneling.com

Iowa TrenchlessJason ClarkPO Box 846, 222 SE 12th St.Panora, IA [email protected]

James W. Fowler Co.John Fowler, VP Sondra Jamison, Marketing Manager PO Box 489 Dallas, OR 97338 USA 503-623-5373 [email protected] www.jwfowler.com Large Diameter Tunneling Tunnel Linings Relining Auger Boring Microtunneling Pipe Jacking Shafts Tunneling-Large Diameter

Jay Dee Contractors Inc Tom DiPonio3881 Schoolcraft Rd. Livonia, MI 48150 USA 734-591-3400 www.jaydeecontr.com Large Diameter Tunneling, Large Diameter Shaft Drilling, Dewatering, Microtunneling, Pipe Jacking, Shafts, Tunneling-Large Diameter

JR Cruz Corp.Evarett Cruz Jr., P.E.675 Line Rd.Aberdeen, NJ [email protected]

Kiewit Construction Co 1000 Kiewit Plaza Suite E200 Omaha, NE 68131 402-346-8535 www.kiewit.com Drilling, Tunneling-Large Diameter, Shafts, Pipe Jacking, Microtunneling, Relining, Tunnel Linings, Tunnel Support, Large Diameter Shaft Drilling, Raise Bore, Jet Grouting, Slurry Wall, Ground Freezing & Dewatering, Large Diameter Tunneling, Grouting

Lametti & Sons Inc. Guy Larson, VP PO Box 375 Hugo, MN 55038 United States 651-426-1380 [email protected] www.lametti.com Auger Boring , Relining, Seals, Auger Boring, Dewatering, Microtunneling, Pipe Jacking, Shafts, Tunneling-Large Diameter, Tunnel Linings, Tunnel Support, Large Diameter Shaft Drilling, Grouting, Pipe Jacking , Dewatering, Microtunneling, Drilling, Large Diameter Tunneling, Grouting, Design/Build, Cost Estimation

Michels Tunneling Ray Post 16500 W. Rogers Dr. New Berlin, WI 53151 United States 262-814-0100 www.michels.com Pipe Jacking , Microtunneling, Shafts, Drilling, Large Diameter Tunneling, Large Diameter Shaft Drilling

Midwest Mole Dan Liotti, PE, President Jason Miller, VP 2460 N Graham Av. Indianapolis, IN 46218 USA 317-545-1335 [email protected] www.midwestmole.com Large Diameter Tunneling, Relining, Microtunneling, Pipe Jacking, Tunneling-Large Diameter, Other

Nada Pacific Corp.P.O. Box 8 Caruthers, CA 93609 559-864-8850 www.nadapacific.com

Northeast Remsco Construction Inc. Alberto Solana, Sr. VP Engineering Richard Palmer, Tunneling Manager 1433 Route 34 South Building B Farmingdale, NJ 07727 United States 732-557-6100 [email protected] www.superna.com Large Diameter Tunneling, Divers, Auger Boring, Microtunneling, Pipe Jacking, Grouting

Northwest Boring Co. Inc.Don Gonzales13248 NE 177th Pl. Woodinville, WA [email protected] Boring , Rock Drilling , Pipe Jacking , Pipe Ramming , Microtunneling

Southland Contracting, Inc. 616A Shelby Rd. Fort Worth, TX 76140 USA 817-293-4263 [email protected] www.scitunneling.com Drilling, Tunneling-Large Diameter, Shafts, Pipe Jacking, Microtunneling, Dewatering, Divers, Large Diameter Shaft Drilling, Jet Grouting, Ground Freezing & Dewatering, Large Diameter Tunneling, Grouting

Super Excavators Inc.Pete Schraufnagel, VP N59 W 14601 Bobolink Ave. Menomonee Falls, WI 53951262-252-3200 [email protected] Boring , Microtunneling, Tunneling-Large Diameter, Sliplining, Pipe Ramming , Pipe Jacking , Grouting, Pipe Bursting/Splitting , Pipe Fusion , Shafts

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Taisei Corporation Alan Hobelman, VP of US Office Tsutomu Segawa, General Manager 6261 Katella Ave. Irvine, CA 90630 USA 714-886-1530 [email protected] www.taisei.co.jp Tunneling-Large Diameter, Shafts, Pipe Jacking, Microtunneling, Demolition, Tunnel Linings, Tunnel Support, Large Diameter Shaft Drilling, Jet Grouting, Slurry Wall, Ground Freezing & Dewatering, Large Diameter Tunneling, Tunnel Inspections, Design/Build

Triad Engineering & Contracting Co.Clifford Kassouf Phil Kassouf7575 Northfield Road Walton Hills, OH [email protected] www.triad-engineering.com Large Diameter Tunneling, Large Diameter Shaft Drilling, Tunnel Support , Tunnel Linings , Auger Boring, Dewatering, Pipe Jacking, Shafts, Grouting

Vadnais Corp.Paul Vadnais, PresidentDan Schitea, VP2130 La Mirada Drive Vista, CA [email protected] Microtunneling

Walter C. Smith Co., Inc.Ben Genco, Administrative Assistant849 Osmun Circe Clovis, CA [email protected] Boring , Pipe Jacking , Pipe Ramming , Tunneling-Large Diameter, Microtunneling

Willco Far West Frank Willden, CEO 3435 W. 500 S. Salt Lake City, UT 84104 United States 801-886-2111 [email protected] www.willcofarwest.com Auger Boring , Pipe Jacking , Microtunneling, Drilling, Large Diameter Tunneling

BORING MACHINE MANUFACTURERS/SUPPLIERSAkkerman Inc. Steve Garbisch, Sales & Leasing Robin Lorenzen, Sales & Leasing

58256 266th St. Brownsdale, MN 55918 United States 800-533-0386 Fax: 507-567-2605 [email protected] www.akkerman.com Pipe Jacking, Microtunneling, Large Diameter Tunneling, Microtunneling Systems/Equipment, Tunnel Boring Machines, Used/Rental Equipment, Machine Service/Repair

American Augers Inc.PO Box 814West Salem, OH 44287419-869-7107www.americanaugers.comGuided Boring Equipment, Mud Systems

Barbco315 Pekin Ave., SEEast Canton, OH [email protected] Boring, Microtunneling Systems/Equipment, Used/Rental Equipment, Tunnel Boring Machines

Herrenknecht Tunnelling Systems USA Inc. 1221 29th St. NW Ste. DAuburn, WA 98001253-833-7366jbrockway@herrenknecht-usa.comwww.herrenknecht.deCutters, Microtunneling Systems/Equipment, Used/Rental Equipment, Survey/Guidance Instrumentation

Icon Equipment Distributors Inc.Brian Crandall300 Ryders LaneEast Brunswick, NJ 08816800-836-5011b.crandall@iconjds.comwww.iconjds.comMicrotunneling Systems/Equipment, Guided Boring Equipment, Used/Rental Equipment

Michael Byrne Mfg.Jim Weist1855 Earth Boring Rd., PO Box 444Mansfield, OH [email protected] Bits, Used/Rental Equipment, Guided Boring Equipment, Microtunneling Systems/Equipment, Engineering/Design

Microtunneling Inc.Timothy R. CossPO Box 7367 Boulder, CO 80306303-444-2650timcoss@microtunneling.comwww.microtunneling.comCutters, Pipe-Polymer Concrete, Mud Recycling, Locators, Mud Systems, Microtunneling Systems/Equipment, Lubrication, Solids Control/Separation, Disputes Review, Education/Research, General Consulting

TBM Exchange International Peter J. Tarkoy 17 Everett St. Sherborn, MA 1770 United States 508-650-3600 [email protected] www.tbmexchange.com Cutters, Microtunneling Systems/Equipment, Tunnel Boring Machines, Used/Rental Equipment

Technicore Underground Corp. Tony DiMillo, President Lynn Jackson, VP

102 Bales Dr East PO Box 93089 Newmarket, ON L3Y 8K3 Canada 905-898-4889 [email protected] www.technicore.ca Grouting, Pipe Jacking , Microtunneling, Shafts, Drilling, Drills & Rigs, Microtunneling Systems/Equipment, Tunnel Boring Machines, Tunnel Linings

The Robbins Company29100 Hall St.Solon, OH [email protected] Boring, Tunneling Products, Tunnel Boring Machines

Vermeer1210 Vermeer Rd. EastPella, IA [email protected] Boring Systems


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ADVERTISER PAGE

Barbco . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M-7WWW.BARBCO.COM

Benjamin Media Resource Center . . . . . . . . . . . M-3 WWW.BENJAMINMEDIA.COM/BOOK-STORE

BMI Buyer’s Guide . . . . . . . . . . . . . . . . . . . . . . . M-34 WWW.BMI-BUYERSGUIDE.COM

Bradshaw Construction Corp . . . . . . . . . . . . . . M-33 WWW.BRADSHAWCC.COM

Brierley Associates LLC . . . . . . . . . . . . . . . . . . M-13 WWW.BRIERLEYASSOCIATES.COM

Brierley Associates LLC . . . . . . . . . . . . . . . . . . M-34 WWW.BRIERLEYASSOCIATES.COM

KingKong Tools . . . . . . . . . . . . . . . . . . . . . . . . . M-17 WWW.KINGKONG-TOOLS.COM

ADVERTISER PAGE

2013 Microtunneling Short Course . . . . . . . . . . . M-5 WWW.MICROTUNNELING.COM

Microtunneling, Inc . . . . . . . . . . . . . . . . BACK COVERWWW.MICROTUNNELING.COM

NASTT’s 2013 No-Dig Show . . . . . . . . . . . . . . . M-35 WWW.NODIGSHOW.COM

Northeast Remsco Construction Inc . . . . . . . . . M-31 WWW.NORTHEASTREMSCO.COM

Permalok Corp . . . . . . . . . . . . . . . . . . . . . . . . . . M-19 WWW.PERMALOK.COM

U .S . Composite Pipe South, LLC (USCPS) . . . . . M-9 WWW.FLOWTITEPIPE.COM

Ward & Burke Construction Limited . . . . . . . . . M-15 WWW.WARDAND BURKE.COM


w w w . t u n n e l i n g o n l i n e . c o m

U191_32-36.indd 34 11/1/2012 4:35:22 PM

U191_32-36.indd 35 11/1/2012 4:35:24 PM

CONGRATULATIONS to Frank Coluccio Construction

OWNERCity and County of Honolulu

PROJECT Beachwalk Force Main phase 1

Longest Curved Microtunneling Project and the First Compound Curve Drive in the US. 1,225 feet

Microtunneling Engineering by Yogi Kwong EngineersMachine by Rasa Industries

Guidance by Tokyo KeikiAncillary Equipment by Microtunneling, Inc.

5 Drives Totaling 5,800 feet x 81.6”/85” OD Pipe

U191_32-36.indd 36 11/1/2012 4:35:25 PM

Documents

U191 1-5.indd 1 11/1/2012 10:33:32 AM · • The face of the MTBM typically can’t be accessed to change cutters or re-move obstructions. • The contractors tended to use the MTBM