Location: Thornton Tomasetti Office (120 Broadway)
Date and Time: Tuesday, May 06 - 5:00PM
Speaker: Robert LaMagna, P.E., Jin Park, P.E., and Arpana Sabu, P.E.
Abstract: The 207th Street Yard is a 45-acre storage and maintenance yard for New York City Transit subway line trains and equipment, located on Harlem River in Manhattan and is accessed by three tunnel portals as well as a flyover track that connects to an elevated transit line, connecting the rail yard to the subway system serving New York City. In response to the flooding during Superstorm Sandy in 2012, the Consultant designed flood mitigation and resiliency measures to protect the rail transportation system, including 3000’ of perimeter floodwalls, supplemental pump systems to control drainage, wall posts to receive and handle floodgate loadings, upgrade of communication systems, and protection of utilities passing through the floodwall limits. This presentation will focus on design challenges due to the active subsurface features: Tunnel portal floodgate supports, maintenance yard floodgate supports and deep foundations; buttress type floodwalls to supplement existing perimeter structures, pile cap and floodwall design to isolate subsurface effects from sensitive utilities. Design criteria will be reviewed and analysis methods described to support construction phase changes while maintaining design intent to protect the yard and transit system from storm surges.