Atlantic Avenue Viaduct Rehabilitation, Phase 1, Brooklyn, N.Y.
Most of the demolition and construction work associated with the first $93 million phase of the Atlantic Avenue Viaduct Rehabilitation project in Brooklyn, N.Y. transpired on weekends to minimize disruption to MTA Long Island Rail Road trains. Even so, Kiewit Constructors of Woodcliff Lake, N.J., completed the job five months ahead of schedule.
“We tried to accomplish a tremendous amount of work in a short period of time, with half of the viaduct open with live running trains and third rail,” says Wayne Thomas, area manager for transit and transportation for Kiewit Constructors.
Kiewit began the design-build project for MTA LIRR in March 2008 and substantially completed it in November 2009. LIRR President Helena Williams attributes much of the success to good management. Rehabilitating the 110-year-old, elevated, steel structure required replacing the longitudinal girders and cap beams, column and foundation repairs, and installing a new track structure.
“We got the viaduct ready for the next 100 years,” Williams says.
Structural engineer HNTB of New York developed a design concept in which the entire upper portion of the column was removed. Instead of bolted girder splices, the team introduced an in-span hinge to enhance constructability and geometry control.
Kiewit implemented a span-by-span construction approach with a system of temporary supports that transferred loads from the superstructure to existing supporting columns, allowing removal of half the superstructure, while the other half carried train traffic.
“We removed large sections of steel spans pulling everything out in one shot and putting everything back in in one shot,” says Kevin Thomlinson, chief program officer and head engineer on the project for LIRR.
The team met after each outage to discuss what went well and what could be improved. As a result, Kiewit finished the job in 30 rather than 36 weekends.
Kiewit tried to completed as much work ahead of the outages. As steel arrived from the fabricator, Kiewit “dressed the spans,” applying the ties, J-bolts and fiberglass walkways. At the viaduct, crews positioned supplies, predrilled holes, added bolts and prepared for the following weekend’s work.
Kiewit purchased a high-capacity, 100-ton crawler crane with a telescopic hydraulic boom that could make lifts while occupying only two lanes, leaving a third lane open to traffic.
Kiewit is now completing the project’s $77 million phase 2, funded with American Recovery and Reinvestment Act money. Williams says the early completion of phase one was key to using the stimulus dollars. Kiewit has applied the same principals to the second phase and has continued striving to shave time off the schedule.
“We continue to get better,” Thomas says. “We’re having similar, if not more successes.”
Developer/Owner: MTA Long Island Rail Road, Jamaica, N.Y.
General Contractor: Kiewit Constructors, Woodcliff Lake, N.J.*
Construction Manager: LiRo Engineers, Syosset, N.Y.
Structural Engineer: HNTB Corp., New York
*Submitted Project to New York Construction