Valhalla, 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.“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 iconjds.com or call 800-836-5011.