An almost impossible task needed to be completed for the Manhattan West construction project – build a plaza over the busiest set of railroad tracks in the busiest city in America, without bringing traffic to a screeching halt. This dauting task was simplified by using a precast concrete design. Jersey Precast Corporation, a Mid-Atlantic Precast Association producer member, was a partner in the project, which received honors.
The Manhattan West project, located over the tracks leading into Penn Station in Manhattan borough, New York City involved erecting a massive platform over the rail tracks leading into Penn Station without disrupting the 55 rail lines that ran constantly underneath.
Along with not stopping traffic, a key component of the project was finding a way to span the 240 feet without installing intermediate steel columns, which would be too close to the rails to be safe. The structure also needed to be highly fire resistant. The project designer achieved all these high-performance goals using massive precast concrete spans in a segmental box and lift design. Due to the strength of precast concrete, no additional supports were needed. Since precast concrete is noncombustible, no fireproofing was necessary.
A total of 612 precast concrete pieces were manufactured at the Jersey Precast facility in Hamilton, N.J. Each piece weighed roughly 56 tons. They were delivered into Manhattan by trucks over the course of five months, where the erection crew assembled them overnight when there is minimal train traffic. In the end, all were thrilled that the project was successfully completed without interrupting rail service. This is one example of using a newer construction technique to achieve project goals.