Three Point Construction Successfully Completes First Ever Front Steer Microtunneling Project in the USA with Icon Tunnel Systems

Laurel, MD – Three Point Construction Inc., of Mechanicsville, MD has successfully completed the first ever Front Steer Microtunneling project in the USA with a Bohrtec BM400L machine from Icon Tunnel Systems.

Three Point Construction Inc. was contracted by C.J. Miller of Hampsted, MD as the tunneling subcontractor for a difficult utility project located at the Applied Physics Laboratory at Johns Hopkins University. As part of the work Three Point had to install a 200LF, 42 inch diameter steel casing that would accommodate a large duct bank with 24 individual conduits for a new high speed communications system. Having already completed work on this project gave the contractor a direct knowledge of the soil conditions that would be encountered. At the location of the bore the conditions were going to be very hard schist with a high content of silica and hard quartz.

“This bore would had to be extremely accurate because we have to maintain a minimum distance beneath existing utilities such as two water lines, a gas main, numerous communications duct banks, the main electrical feed to the campus, two causeway footings and the root systems of two oak trees” says Mike Boyd, President of Three Point Construction, Inc. “With only inches to spare on either side of the 42 inch steel casing in the receiving pit due to an existing duct bank and building footing, accuracy and precision on line and grade were paramount,” Boyd continues.

Due to the difficult nature of the project, Three Point decided to do some homework and research a variety of trenchless alternatives to conventional auger boring. Three Point had past experience on several jobs with Pilot Tube Microtunneling Systems rented from ICON, but they also knew it was only designed for use is soft, displaceable soil and not hard ground conditions. “The pilot tube system would not have penetrated the soil due to its density and the presence of quartz,” says Boyd. “In addition, the manual steering and lag head would not have been precise enough to hit the target. We then considered using a tunnel boring attachment as the only other viable alternative.”

Three-Point1However, it was ultimately decided that the tunnel boring attachment would not be feasible due to the amount of time for setup and dismantle. The size of the tunnel boring attachment would also prove to be an issue as Three Point would need a crane for the installation and dismantle process. “The crane required to make the lift would have been costly and there was also no room to set it up”, says Mike.

Running out of ideas, Three Point then contacted ICON Tunnel Systems for possible alternative solutions. Due to the hard soil conditions and extremely tight line and grade tolerances required, ICON recommended the Front Steer Microtunneling System from Bohrtec. The Front Steer System makes it possible for the contractor to excavate the soil while establishing the line and grade instead of displacing it like the Pilot Tube/PTMT method. Employing a full cutting face, a pilot tube theodolite guidance system with CCTV monitor, and an illuminated LED target directly behind the cutting head, the operator maintains constant control of line and grade.

As the Front Steer Boring Unit is advanced in the ground, the operator can see the position of the cutting head with respect to the intended line and grade at all times and make any necessary corrections to maintain that line and grade. On this particular project, ICON recommended that the 16 inch diameter Front Steer System be used to establish the exact line and grade and then the contractor would follow with his conventional American Augers Boring Machine to install the required 42 inch diameter steel casing.

Several successful Front Steer Microtunneling projects had already been completed in Europe in varied ground conditions but not yet in the United States. This was a concern of the contractor, but with the proven track record on several projects in Europe, specifications that met the project’s needs, and a company like ICON backing them up, Three Point quickly approved the Front Steer System for use on his project. According to Boyd, “This was the only system that we believed could deliver the accuracy required for the job in these soil conditions.”

Rob-and-Dan-Front-SteerICON was able to quickly mobilize the required equipment and coordinated with all parties on every step of the delivery, setup, and operation. “Because of the critical nature of the project, we flew in Bohrtec’s Lead Operator/Field Engineer for the Front Steer System, Stefan Janssen from Germany to provide training and support,” says David Crandall, Vice President of Icon Tunnel Systems. “We also had Dan Paster, our National Guided Auger Boring Consultant and Operator, as well as Rob Langenbach, Operations Manager and Chief Operator for ICON on site with Three Point.”

By the time Stefan arrived on site, the Bohrtec BM400L and Front Steer System had been delivered and assembled, taking ICON and the Three Point crew only one day.

From the beginning, crews from ICON and Three Point worked seamlessly throughout the entire operation. The Front Steer System was powered and driven through the ground by one of Bohrtec’s smaller long frame machines, the BM400L, with 100 tons of jacking force and approximately 14,500 foot-pounds of torque. Roughly halfway through the drive the system encountered two separate locations containing solid quartz rock ranging from 6 to 8 feet in length each time. “The Front Steer went right through the rock,” claimed Boyd. “Typically when you hit rock like that with another boring system, it will completely destroy the head. The Front Steer was in great shape when it arrived at the receiving pit.”

The Front Steer arrived successfully at the receiving pit/existing manhole within 1/10 of one inch of line and grade, without disrupting or damaging the various utilities and other obstacles that were near the bore path. Production and excavating rates reached an average of 13.5 feet per hour, keeping Three Point way ahead of schedule. “Our operators were able to constantly monitor the exact position of the Front Steer Boring Unit using an illuminated LED target, theodolite camera and CCTV monitor. This technology allows the operator to make corrections to the intended line and grade as needed in real time similar to conventional computer-controlled, laser-guided microtunneling with half the headaches and half the equipment,” says Crandall.

Three Point then upsized and completed the bore by following the line and grade established by the Front Steer with their American Auger boring machine pushing 42 inch steel casings with large augers inside.

Three Point was able to successfully finish the 42 inch casing bore following the Front Steer within a matter of two days including setup of his machine. The total project, including the Front Steer operation, was completed two weeks ahead of schedule and under budget. “We could not have done this job without Icon,” says Boyd. “Once we understood the system and process, we had total confidence that the end result would be a success.”

ICON Tunnel Systems has steadily grown in technology and expertise to become a full-service company and industry-leader in Pilot Tube Guided Auger Boring and Front Steer Microtunneling for the trenchless construction of pipelines, sewers, and other various underground utilities. ICON Tunnel Systems has the in-house resources to handle projects of any size in any location across North America and provides a comprehensive line of services that include consulting, design, engineering, manufacturing, distribution, leasing and equipment rentals.

Cambridge Case Study

PullingHeadAssemblyPilot Tube Guided Auger Boring Takes on Horizontal Directional Drilling (HDD)
by ICON Tunnel Systems, Kleinfelder/S E A and Brierley Associates, LLC

Trenchless pipe installation such as Pilot Tube Guided Auger Boring is quickly becoming a popular way to install pipe as an open cut alternative. This method minimizes disruptions and costs, while proving to be an effective way to install pipe.

Pilot Tube Guided Auger Boring was developed in Germany by Dr. Peter Uffman of Bohrtec for the installation of trenchless house connection sewer pipes. The technology was later developed further to install mainline sanitary sewer pipes on line and grade over 300’ from manhole to manhole as an alternative to expensive tunnel boring machines.

For years, pilot tube machines have been installing steel, clay and other types of jacking pipes, but we are now seeing these systems expanding their role into High Density Polyethylene (HDPE) and other pullback pipe installations. Pilot tube machines can now install multiple types and sizes of pipe on one project while still achieving the pinpoint like accuracy for which they are known.

A recent project in Cambridge, MA highlights the pilot tube machines’ application versatility by installing HDPE and Hobas pipe as well as the benefits over Horizontal Directional Drilling (HDD) for this particular project.

The Project:
The Cambridge Park Drive Drainage Improvement project is one aspect of the Massachusetts Water Resources Authority’s (MWRA) long term combined sewer overflow control plan for the Boston Harbor clean-up. This project was a key element of the Alewife Sewer Separation Project that will separate the combined sanitary wastewater and storm water infrastructure in the West Cambridge portion of the city.

Construction of this project will provide significant environmental benefits by eliminating the existing combined sewer outfall near the city’s public drinking water supply, minimize flooding in West Cambridge, protect Fresh Pond Reservoir from flood waters, and will reduce the discharge of pollutants to the Little River, which is tributary to the Alewife Brook, Mystic River, and Boston Harbor.

This project involves the construction of approximately 3,000’ of a new 8’ by 4’ box culvert that crosses several large business parcels and nine rail crossings, two of which are active high speed commuter rails. The box culvert will convey the newly separated storm water to a new storm water wetland basin where pollutants found in storm water will be treated by native vegetation and aquatic plants, detention, soil infiltration, and evaporation/transpiration before being discharged into the Little River.

Existing utilities of water, sewer, electric, gas and telecommunications all crossed the area of the new wetland basin and needed to be relocated as one of the first phases of work. The existing utilities cross the reservation and the Little River, both above and below-grade.

A soil investigation that included 17 test bores drilled to depths of 18’ to 37’ below ground surface found the following soil from ground surface down; fill, organic deposits, marine sand and marine clay. Engineers determined that the marine clay soil located approximately 8.3 feet below the river bed would be suitable for pipe installation.

Project Challenges:
Trenchless design engineers at SEA/Kleinfelder and Brierley Associates, LLC originally designed the Little River crossing as a horizontal directions drilling (HDD) installation. However, after the project was bid and awarded, the property owners on either side of the HDD crossing had concerns of construction disruption such as the considerable construction footprint needed for the HDD staging areas, and the extensive pipe laydown areas and drill path set up that would impact business operations and employee parking. As a result of prolonged and unsuccessful easement negotiations, a change of ownership for the property intended as the laydown area, as well as a new accelerated completion deadline by the property owner at the other end of the HDD, the project team realized that another construction method was needed.
The risk of frac-out was also a concern. HDD uses drilling fluids (drill mud) during the drilling and reaming procedure that are pumped at a high pressure through the drilling tools in order to transport/remove soil cuttings back to the receiving pit and to cool the drill bit, reamer and tracking system. Frac-out can be caused at times when the drill mud is being pumped at a high pressure while drilling in looser soil that cannot contain these pressures. When frac-out occurs, drilling fluids get injected into the surrounding soils/environment and possibly other surrounding utilities. To avoid this problem using HDD at the Cambridge project, operators would need to install the pipe at a depth sufficient to contain the drill fluid pressure, yet not so deep that the integrity of the HDPE pipe would be compromised by the ground pressure, also known as buckling. The minimum depth below the bottom of the river to avoid frac-out, as determined by the design engineers, was approximately 29ft.
HDD also required a 12.5’ offset between parallel bores to minimize cross-hole disturbance and drill fluid contamination.

These challenges lead the city, consultant team and the contractor to search for an alternative method for pipe installation. This portion of the project essentially became a design/build entity. The team would need to redesign the utilities crossing portion of the project in order to keep the project on budget and within the new constraints.

BoringUtility Installation Solution:
Engineering consultants Kleinfelder/SEA Consultants of Cambridge, MWH Americas Inc. of Boston and Brierley Associates, LLC, of Manchester, NH evaluated the possibility of Pilot Tube Guided Auger Boring as an alternative utility installation method for the project. After meeting with ICON Tunnel Systems regarding the Pilot Tube system and capabilities, the engineers developed an HDD/Pilot Tube comparison spec table.

Pilot Tube Equipment:
The pilot tube machine required for the project was a Bohrtec BM600LS (265 tons jacking force and 22,500 ft-lbs torque) powered by a 75 Kilowatt Hydraulic Power Unit and Theodolite guidance system. Other equipment required included 5.5” O.D. double wall pilot tube rods, bentonite lubrication system for pilot tube rods, 16.5” O.D. casings and augers and a 38.3” O.D. hydraulic powered extension kit for the 36” I.D. Hobas jacking pipe. ICON supplied a 250psi bentonite mixing pump and 3,000psi-high pressure water pump station for jetting. For the HDPE pipe installations, a 4” pulling adapter designed and manufactured by ICON Tunnel Systems and an 8” pulling adapter/expander cone designed and manufactured by Bohrtec were also required. For the 8” HDPE line, NSTAR Gas, the local utilities provider, required that the forces acting on the pipe did not exceed a certain threshold. A special sensor was selected by the consulting team to monitor the forces being placed on the HDPE pipe during installation. The sensor system used was a Tensi Trak unit manufactured by Digital Controls Inc.

The utilities that would be installed consisted of three (3) 4” HDPE lines for AT&T Telecommunications, one (1) 8” HDPE line for NStar Gas and a 36” Hobas line for NStar Electric. Each drive would be 430 feet in length. The three (3) 4” HDPE lines were first to be installed followed by the 8” HDPE line and finally the 36” Hobas pipe. The invert of the largest pipe was approximately 23 feet below surface grades surrounding the river.

BoringImage2Installation Process:
The installation process consisted of constructing two pits, a jacking pit and receiving pit. The jacking pit was 26’L x 20’W x 24’D in size where the Pilot Tube machine would be positioned and the receiving pit was 20’L x 20’W x 20’D in size.

4” and 8” HDPE Installations:
These installations were completed using a two phase method. Once the pilot tube machine was assembled in the jacking pit, the contractor, P. Gioioso & Sons, Inc. of Hyde Park, MA along with ICON Tunnel Systems would start the pilot bores. Once the pilot bores reached the receiving pit successfully on line and grade, the team would then remove the pilot head and replace it with the pulling adapter which was attached to the HDPE pipe. A Tensi Trak sensor unit was used when pulling back the 8” HDPE pipe. As the pipe was pulled into place the pilot tube rods were removed in the jacking pit. Both the 4” and 8” pipe used fusible pulling heads supplied by POLY-CAM, Inc. out of Anoka, MN.

The 8” pulling adapter/expander that was used has three water jets in front of the cone and a single bentonite port located in the back. The water jets assist in loosening the soil ahead of the expansion cone. This reduces the pulling forces acting on the pilots, adapter and the pipe. The bentonite is used to lubricate the outside of the pipe and bore path reducing skin friction.

Sensor Tracking Results:
Monitoring the forces placed on the HDPE pipe during installation was essential because if the pilot tube system exerts too much pulling force on the pipe it could elongate which reduces the wall thickness. If this should happen, would reject the pipe and the team would have to perform another installation, wasting valuable time and money.

The force threshold proved by for the HDPE pipe was 18,000lbs. During the pullback process, the forces maxed around 7,000 to 8,000 lbs, well below the threshold.

36” Hobas Pipe Installation:
Installation of the 36” Hobas pipe required the team to perform the traditional Pilot Tube Three Phase installation. They first established the pilot bore successfully on line and grade. They then attached the 16.5” auger head to the last pilot tube to expand the bore path diameter. The 16.5” steel casings with augers would follow the auger head until it reach the receiving pit. The team attached the 38.3” Hydraulic Extension kit to the last 16.5” steel casing to increase the bore diameter to its final size. The 36” I.D. Hobas product pipe would follow the 38.6” Hydraulic Extension kit on line and grade to the reception pit. The 36” Hobas pipe installation is one of the longest for this size and type of pipe to date using this process of installation.

What was Learned on the Cambridge Project:
• The project footprint was reduced by using Pilot Tube Guided Auger Boring.

• 5 pipes can be installed in close proximity out of one pit using Pilot Tube Guided Auger Boring. (3) 4” HDPE, (1) 8” HDPE and (1) 36” Hobas pipe.

• Installation of various types and sizes of pullback and jacking pipes (HDPE and Hobas) can be installed successfully on line and grade using one method and machine (Bohrtec BM600LS) instead of multiple methods and machines to accomplish this same task.

• Pilot Tube Guided Auger Boring reduced the risk of frac-out under the river versus HDD on this project.

• Given the success of the pullback installations on this job, we can safely say the Pilot Tube Guided Auger Boring process is a 100% field proven method for the successful installation of HDPE or other plastic pullback pipe for that matter.

Typically, projects that require HDPE pipe to be installed are designed with the HDD method of installation. By converting the project to the Pilot Tube Method, the team was able to meet their worksite constraints set by the property owners and achieve a successful installation of HDPE pipe with a bullet like line and grade accuracy without the fear of frac-out due to the specialized Pilot Tube Guided Auger Boring equipment used and supplied.

Parties Involved:
This project was undertaken by the Cambridge Department of Public Works (CDPW), in coordination with the Massachusetts Water Resource Authority and MA Department of Conservation and Recreation. Engineering consultants were John J. Struzziery, P.E.,Kleinfelder/S EA Consultants of Cambridge; MWH Americas Inc. of Boston; Nick Strater, P.G., Brierley Associates, LLC, of Manchester, NH; and the Bioengineering Group of Salem, MA. The general contractor for the project was P. Gioioso & Sons, Inc. of Hyde Park, MA and the Pilot Tube equipment and operators were provided by Daniel Paster and Andreu Kerry, ICON Tunnel Systems, East Brunswick, NJ. Ph: 800-836-5011

Trenchless Construction Completes One of the First Pilot Tube Projects in Washington State with the Help of ICON

Sedro-Woolley-1Sedro-Woolley, WA – Trenchless Construction Services L.L.C., of Arlington, WA has successfully completed one of the first pilot tube projects in Washington State using ICON’s slide rail system and Bohrtec BM400LS pilot tube micro-tunneling machine.

Sedro-Woolley, a small quaint logging town in Washington State has recently begun increasing their trenchless pipe installation program due its proven success. Trenchless pipe installation minimizes disruptions and costs, while proving to be an effective way to install pipe.

Giordano-Icon-3Trenchless Construction Services L.L.C. a trenchless pipe installation and replacement construction company was the general contractor for the $3.5 million dollar Sedro-Wooley SR9 Township trenchless sanitary sewer improvement project. Trenchless was responsible for installing 14 manholes and 3,400 lineal feet of 15 inch diameter and 24 inch diameter gravity sewer pipes at a .16% grade. Trenchless methods were required for this project because the pipe was to be placed under and adjacent to State Highway Route 20 and State Highway Route 9. “These methods were used because of a lack of detour options to maintain traffic flow,” says John Gustafson, Owner/ Manager of Trenchless Construction Services L.L.C. “The soil conditions, as well as the accuracy of pilot tube micro-tunneling, also made it the preferred method for the 15 inch and 24 inch portions of the project.”

Pilot tube micro-tunneling, also referred to as guided auger boring, was introduced in the 1990s for the installation of small diameter sewer pipes and water lines. Guided auger boring systems are similar to micro-tunneling systems with the addition of a guidance system. This accurate guidance system consists of a camera-mounted theodolite to ensure a high accuracy of the line and grade. “We choose the Bohrtec guided auger machine because we knew it would give us bullet like accuracy,” says Gustafson.

Sedro-Woolley-5Prior to construction, Trenchless sponsored a meeting with engineers, sub-contractors and Trenchless employees in order to get everyone on the same page. ICON, the New Jersey-based slide rail system manufacturer and Bohrtec pilot tube distributor and Mission Clay, the No Dig clay pipe manufacturer both made presentations of their products. “Our goal was to make sure all parties had a clear view of the project scope as well as the products we were going to use,” says Gustafson. “This was very beneficial as everyone was able to ask questions and get direct answers from the manufacturers.”

This project would require a total of six jacking pits in which Trenchless would place the pilot tube boring machine to jack the sewer pipe between manholes. These jacking pits were dug using a hydraulic excavator weighing 54,000 lbs.

Trenchless used ICON’s slide rail system to shore the six jacking pits, which were 11 feet wide by 20 feet long by 14 feet deep. This slide rail system is designed and built to withstand the jacking forces of the Bohrtec BM 400LS pilot tube machine.

“ICON’s slide rail system is very easy to install, which saved us a tremendous amount of time,” says Gustafson. “The slide rail system reduces setup time and is substantial enough to withstand the forces of the BM 400LS.”
This slide rail system also features temporary sheeting, which allows the contractor to extract small sheeting panels rather than large shoring panels to create an opening for the pipe installation.

The Bohrtec BM 400LS, with a jacking force of 150 tons and 75 tons of pull back force, can perform guided drillings in one, two or three phase procedures such as pilot drilling, reamer drilling with steel protective piping; alternative reamer drilling with pushing of product pipes at the same time and drilling with welded steel pipes.

Trenchless first performed the three-phase guided drilling installation with the 24 inch diameter clay pipe. The three-phase procedure consists of installing the pilot tube to secure an accurate line and grade. When the pilot tube reaches the receiving shaft, a 16 inch casing with an auger inside is connected to the last section of pilot tube in the jacking pit. The 16 inch casing with auger is jacked into place as the soil is extracted, following the pilot tubes. Once the casings and augers reach the receiving pit, a reamer is attached to the 16 inch casings. This reamer enlarges the bore hole to that required for the 24 inch clay pipe. The 24 inch clay pipe is then jacked to the receiving pit, following the 16 inch casings and reamer.

Trenchless then moved on to the next phase of the project, which was installing the 15 inch diameter pipe. Trenchless would only use the two- phase procedure for this installation. “We were able to jack the clay pipe after the initial pilot tube drilling with the casings because of the smaller pipe diameter,” says Gustafson.

Trenchless purchased the 15 inch pipe auger and casings for the project and rented the larger auger and casings for the 24 inch pipe from ICON. “ICON was instrumental in securing the tooling and special equipment required for the specific pipe sizes on the project,” continues Gustafson. “ICON’s personnel were always available for consultation and visited the project during construction to assure us that we were using the recommended procedures.”
Trenchless was able to complete this first-of-a-kind project for Washington State within the allotted time and avoided equipment malfunction delays. “ICON is a very customer focused, professional and knowledgeable company,” says Gustafson. “Their support and service is top notch. I look forward to a continued relationship with ICON in the future.”

Since 1999, Trenchless Construction Services, L.L.C. has grown to 20 employees and offers horizontal directional drilling, micro-tunneling, pipe ramming and a number of trenchless pipe replacement processes such as pipe reaming, pipe bursting and slip lining. Trenchless is licensed in Washington, Oregon, Idaho, Montana and Alaska.

For more information on Trenchless Construction Services, L.L.C., please call 360-474-0123.

Since 1982, ICON has steadily grown in technology and expertise to become a full-service trench shoring and pilot tube guided boring company and industry-leader in underground construction projects. ICON has the in-house resources to handle projects of any size in any location and provides a comprehensive line of services that include consulting, design, engineering, manufacturing and distribution, leasing and equipment rentals.

ICON’s Transformer Slide Rail Provides Strength and Versatility for Shoring Tunnel Access Shafts

ICON-Transformer-Rail-1East Brunswick, New Jersey – ICON Tunnel Systems, North America’s leading trench shoring and pilot tube guided auger boring sales and service company, now offers their newly designed Transformer Slide Rail System to trenchless contractors as an alternative shoring solution to sheet and shore tunnel access shafts for auger boring, microtunneling, pipe jacking and pipe ramming projects.

“We’ve designed this new rail system for the changing and always challenging trenchless industry,” says David Crandall, Vice President of ICON Tunnel Systems. “Every trenchless road, highway, railway or environmental crossing project requires a safe trench shoring pit to work in, but each job varies and may require different dimensions. This is why we have designed our Transformer Slide Rail System to be a modular sheeting system that can change along with the requirements for the project,” continues Crandall. “The Transformer Rail is the newest addition to our slide rail shoring systems and is 30-40% stronger, which allows for larger clearances and increased working room for auger boring machines and large pipe diameters. The new design also decreases the amount of repairs and maintenance needed by approximately 50% when compared to previous designs.”

ICON’s Transformer Slide Rail is designed to be used in some of the most extreme soil conditions, up to a maximum depth of 36’ in C60 soil. The rail is equipped to handle slide rail panels in lengths ranging from 9.84’ to 20.50’ and with heights of 4’ and 8’. Transformer Slide Rail lengths are available in 14’, 18’ and 26’. The 14’ and 18’ rails will be offered in a double rail configuration. The 26’ rail will be offered in both double and triple rail configurations for shoring deep shafts and trenches.

ICON-Transformer-Rail-2“We designed the Transformer Rail to also handle three different types of bracing with one great rail including; fixed rail, roller rail and angled raker bracing. This is made possible by simply having to change the hardware fittings, not the rail,” says Crandall.

Roller Rail Bracing will allow the contractor to move the bracing cart up and down the face of the Transformer Rail when needed in order to provide large clearances for pipes, culverts, structures or for an easier removal of the cross braces during a re-bracing procedure for open clear-span designs.

Fixed Rail Bracing will allow the contractor to plan ahead before the start of an installation and pin the bracing into specific locations along the face of the Transformer Rail. This ensures a proper assembly and perfect installation of the bracing every time.

Angled Raker Bracing allows the contractor to remove all horizontal cross bracing in the way of the work to be done, providing a large open clear span for bridge piers or large tanks. This type of bracing is ideal for use when “Re-Bracing” with Steel Tie-Back beams are not a viable option.

The competitively priced Transformer Rail System is manufactured at ICON’s headquarters in East Brunswick, NJ. The rails are made out of high grade 50 KSI steel with reinforced headers, pounding plates and ICON’s special impact design. This allows the Transformer Rail to last for 10 to 15 years with minimal maintenance. In addition, a 6 point inspection process that ICON has developed over the years is required with all new equipment, ensuring high-quality manufacturing at all times.

ICON will also supply consulting services for the project. If required, site specific engineering with shop drawings, paper calculations and P.E. Stamp for newly purchased or rented slide rail systems in all 50 states is also available.

Since 1982, ICON has steadily increased their market share and product offerings to become a full-service trench shoring and pilot tube guided boring company and industry leader in underground construction projects. ICON has the in-house resources to handle projects of any size across North America and provide a comprehensive line of services that include consulting, design, engineering, manufacturing and distribution, as well as the ability to lease or rent equipment.

S.E.W. Uses ICON’s Triple Slide Rail System on One of the World’s Largest UV Water Treatment Plants

SEW-004Valhalla, NY – S.E.W. Construction, a joint venture between Skanska U.S.A. Civil Northeast, Inc., ECCO III Enterprises, Inc. of Yonkers, NY and J.F. White Contracting from Framingham, MA. is currently working on one of the world’s largest water treatment plants. The project involves installing approximately 10,000 linear feet of encased pipe that ranges in outside diameters from 48 to 144 inches.

This $1.4 billion UV water treatment plant, scheduled for completion in 2012 will provide 90% of the drinking water for New York City. The UV plant contains 56 UV treatment units, which can each process 40 million gallons of water per day using multiple UV lamps. UV lamps are used to disinfect the water as opposed to using chemicals. UV treatment is becoming the preferred water treatment method because of its ability to disinfect water faster than other methods like chlorination and it’s also more cost efficient.

A section of the massive pipeline required 9-foot diameter, 20-foot long prestressed concrete cylinder pipes (PCCP) to be installed in a very confined and deep section of the project. S.E.W. contacted ICON of East Brunswick, NJ, to design and provide a triple slide rail system that would be able to handle a maximum depth of 25 feet below ground level and over 30 feet in width.

Slide rail systems have become the preferred shoring method for contractors for long runs of larger-diameter pipelines by proving to cut time and labor costs versus conventional steel sheeting methods.SEW-4bays“Installation of a slide rail system requires a smaller crew with components put in place and removed by an excavator,” says David Crandall, Vice President of ICON. “Modular beam and plate design provides flexibility and optimum use on a variety of jobs. There is no need for interior walers or beams, thus allowing for more working room and ease while digging. Slide rail systems also allow multiple operations to be performed simultaneously to expedite work. We find slide rail systems can lower shoring costs from 30 to 60 percent compared to conventional systems.”

“Because the contractor would install 20-foot sections of concrete pipe,” says Crandall. “We had to design the system accordingly by using 20.50-foot-long lining plates for the required horizontal clearance and strong triple rail with large bracing for the 15-foot cantilever required under the bottom brace of the system. This would offer the pipe crew the proper clearance.”

The 20-foot long sections of concrete pipe were set into the trench by a 275-ton crane. The weight from this crane added load and deflection to the side walls of the slide rail system. ICON’s slide rail system was able to handle this high ground pressure from the crane due to the design of the 5-inch thick wall panels manufactured from high grade 50 steel.

“ICON is no stranger to large concrete pipe jobs,” says Richard Odierna, New York Shoring Consultant for ICON. “The section of the slide rail system itself was a six-bay, triple slide rail trench that was 130 feet long, 32 feet wide, and 20 feet deep and was designed in combination with benching and sloping to handle the overburden that would be encountered in certain areas. We also supplied the contractor with extra rail pairs for handling curves and turns in the pipe run.”

Site-specific engineering drawings, calculations and New York Professional Engineered (PE) stamps were submitted by ICON for approval though D.H. Charles Engineering of Santa Rosa, CA.

SEW completed the 9-foot OD concrete pipe installation in late summer of 2009. “Compared with other systems considered for this project, ICON’s slide rail system proved to be the best not only from an engineering standpoint but field technical support as well. If the need arises, I wouldn’t think twice if given a choice to use this system again,” says Mark Giordano, Superintendent for SEW Construction.

Since 1982, ICON has steadily grown in technology and expertise to become a full-service trench shoring and pilot tube guided boring company and industry-leader in underground construction projects. ICON has the in-house resources to handle projects of any size in any location and provides a comprehensive line of services that include consulting, design, engineering, manufacturing and distribution, leasing and equipment rentals.

For more information about ICON and their products, please visit or call 800-836-5011.

Bancker Construction Overcomes Tough Challenges with Pilot Tube Microtunneling in Queens, NY

Bancker-Pepsi-Bohrtec-BM-600LSQueens, NY – Bancker Construction of Islandia, NY successfully completed the installation of two 6” HDPE sewer pipes under the PepsiCo bottling plant foundation using pilot tube microtunneling technology while incorporating a new Pull Back Expander from ICON Tunnel Systems. The new Pull Back Expander is specifically designed to attach to the pilot rods and pull the HDPE pipe back into the pilot hole.

Over the past 5 decades, Bancker has completed numerous sewer line installs. This project however was not your typical installation. The PepsiCo bottling plant had a failing 40 year-old cast iron sewer line located under the plant floor that needed to be replaced. Project Engineers determined that HDPE pipe would be used to replace the sewer line because the size and strength of this pipe met the project’s specifications.

In addition to the plant floor, the two new sewer lines would run under a number of other rooms such as a storage room, refrigeration room and the lab, which happens to be one of the most sensitive areas in the plant. Throughout the construction, the plant was required to stay operational.

“There were many factors to take into consideration while planning this project,” says Charlie Madsen, Vice President of Bancker Construction. “In addition to the new sewer lines needing to be installed in a timely manner without disrupting plant operations, we had to pay close attention to air quality due to the sensitive nature of the bottling process.”

Bancker determined that open cut construction to install the new sewer line was not an option, as it would cause too many disruptions and create too much dust and debris inside the plant. Directional drilling was ruled out due to its lack of accuracy, large site layout and the vibration from tooling that could have potentially disrupted the lab and bottling equipment. They then turned to ICON Tunnel Systems and their pilot tube microtunneling technology as the sewer pipe installation method.

Bancker-Pepsi2“Pilot tube guided auger boring has proven itself over the years to be one of the most accurate methods for installing gravity sewer pipes on line and grade,” states David Crandall, Vice President of ICON Tunnel Systems. “Typically, pilot tube guided auger boring machines jack clay or steel pipe once the initial drive is made. Since this project called for HDPE pipe, we recommended our new Pull Back Expander attachment. This attachment allows us to successfully make the initial bore on line and grade, then pull HDPE pipe back through the bore instead of jacking it. HDPE pipe is typically pulled through the bore as opposed to jacking it with a machine on long drives, as jacking would potentially damage or even destroy the pipe.”

“Another aspect of the project that made pilot tube microtunneling and the Pull Back Expander ideal were the soil conditions and pipe size,” says Dan Paster, National Guided Auger Boring Consultant for ICON Tunnel Systems. “The soil was soft and sandy with trace amounts of gravel and small cobbles, which allowed for further displacement of the soil by the Pull Back Expander after the initial pilot tube install. What this meant was no spoils had to be removed or dealt with during the installation process.”

The microtunnel drives would not be an easy task for Bancker and ICON. They would first excavate the jacking pits outside of the building, next to the foundation walls. The jacking pits were 20’ long x 10’ wide x 8’ deep and shored with Bancker’s ICON steel trench box. ICON Tunnel Systems supplied the Bohrtec BM600LS guided auger boring machine, which was then placed in the jacking pit with the theodolite guidance system.

For the first drive, Bancker hand excavated the 4’ x 4’ tie-in pit, which was 107LF inside the plant from the jacking pit. “The tie-in point was located in the actual bottling section of the plant,” says Madsen. “There was very little room in this particular section of the plant, so storing equipment, HDPE pipe and creating a true receiving pit was not an option.”

To solve the tie-in point issue, Bancker was permitted to excavate a receiving pit in the refrigeration room, which was located between the jacking pit and tie-in point.

Bancker and ICON made the initial drive on line and grade from the jacking pit, through the receiving pit and into the tie-in point. Once the pilot tube reached the tie-in point, they reversed the pilot tube back to the receiving pit. The next step of the drive called for the removal of the pilot tube head and attaching the Pull Back Expander to the front of the pilot rod. “The Pull Back Expander is threaded at the attachment end like a pilot tube head,” says Paster. “Removal of the pilot head and attaching the Pull Back Expander only takes a few minutes.”

Banker-Large-Double-Wall-Pilot-with-Head-in-ClampThey then proceeded with jacking a short portion of the HDPE pipe between the receiving pit and tie-in point. “Because the length from the receiving pit to the tie-in point was under 20’, we were able to successfully jack the HDPE pipe into place,” says Madsen.

The team then attached another HDPE pipe to the head of the Pull Back Expander and successfully pulled the HDPE pipe to the jacking pit. Bancker then fused both pipes together in the receiving pit.

The second drive also used the Pull Back Expander but was located at a different section of the building with a much shorter distance of 76LF.

With both drives, there were a number of existing utilities in the way such as a main water line, roof drainage lines, electrical lines and old brick and cement foundation piles.

“The accuracy of the pilot tube system was crucial as it kept the bores on line and grade though out the project,” says Madsen. “It also allowed us to stay exactly 3’ under the concrete foundation, which eliminated vibrations and heaves in the concrete while boring. In addition, both the pilot tube and Pull Back Expander attachment displaced very little soil during the project. This allowed us to speed up the installation process and finish ahead of schedule as we did not have to deal with removing spoils.”

Since 1982, ICON has steadily grown in technology and expertise to become a full-service trench shoring and pilot tube guided boring company and industry-leader in underground construction projects. ICON has the in-house resources to handle projects of any size in any location across North America and provide a comprehensive line of services that include consulting, design, engineering, manufacturing and distribution, leasing and equipment rentals.

For more information about ICON Equipment, ICON Tunnel Systems and their products, please visit or call 800-836-5011