Foundation Wall Stabilization Completed At Ground Zero 7/8/02
When the 110-story Two WTC collapsed last Sept. 11, it not only crushed the uppermost 20 ft of the reinforced concrete section of wall, it caused the lower 50 ft to bulge in toward Ground Zero, as much as 4.5 ft at the walls top.
The bulge was discovered as debris, which was supporting the 3-ft-thick wall, was removed in preparation for the installation of rows of tieback anchors. The first anchors in the crushed zone went in in March, from the top down (ENR 4/1 p. 14).