11th Avenue Extension in Hudson Yards

LOCATION:

New York City, New York

subsurface conditions::

Urban fill overlying a mixture of medium dense sands and silts becoming till of varying thickness over bedrock at about 30 feet depth

size and solutions:

6,000 square feet of jet grouting, 57 micropiles and 87 tiebacks

partners:

Owner: Amtrak 
General Contractor: Tutor Perini Corporation

project snapshot:

Nicholson created a support of excavation down to bedrock with jet grout walls internally reinforced with micropiles and supported with three levels of tiebacks beneath the 11th Avenue six lane viaduct in New York City. The overall work area was limited because of the main Hudson Yards commercial development site access road, allowing access to only half of the area at a time.  All of the work was completed in only 15 feet of headroom, operating 24 hours a day and adjacent to live railway yard tracks.

11th Avenue Extension in Hudson Yards