World Trade Center - Vehicle Security Center

The joint venture between Nicholson Construction Company and EE Cruz retained GEI as a consultant to design and engineer portions of the new facility. The owner is the Port Authority of New York and New Jersey.

The work consists of constructing a perimeter foundation wall and tying into the existing Liberty Street slurry wall of the existing WTC West Bathtub. The perimeter walls tie into the northwest and northeast corners of the existing Liberty Street slurry wall. The wall is a combination of slurry walls, jet-grout cut-off wall, and secant pile wall.

After construction of the slurry wall, excavation will involve removal of 150,000 cubic yard of soil, 50,000 cubic yards of miscellaneous construction debris from the former Deutshe Bank site, and 13,500 cubic yards of rock.

Most of the slurry wall is supported with tiebacks. Along one wall, tiebacks cannot be used where timber piles support the adjacent historic high rise structure. Along that section, the slurry wall is supported with T-panels and buttresses with continuous reinforcement across the joints.

GEI worked with the JV to address changes in panel layout and conflicts with existing subsurface structures.

The new slurry wall intersected several tiebacks under tension supporting a section of the West Bathtub. GEI designed a resupport system for the existing slurry wall panel to temporarily support the panel during construction and excavation.

GEI designed four temporary and four permanent truss members to span 32 feet between the T-panels and buttresses. GEI engineered the connection between the trusses and buttresses to provide a constructible solution to accommodate deviations in the slurry wall installation.

To minimize risk for the JV and improve production during excavation phase, GEI designed recessed tieback anchors with design loads up to 750 kips. GEI provided design modifications to the internal wales to accommodate the recessed anchors.

Adjacent historic building required building protection for the duration of the project. GEI designed 25-foot tall building protection to act as a screen to deflect soil, mud, and debris.

PANYNJ required the JV to perform borings and obtain rock cores at each panel location. GEI provided field observation for rock coring before construction.

A pedestrian walkway crosses the active construction site. GEI designed bifurcated reinforcing cages to be used in low overhead areas.

GEI developed three-dimensional computer models to evaluate clearance between adjacent tiebacks, existing tiebacks, and existing subsurface structures.