Lincoln Tunnel
Lincoln Tunnel Project Overview The Ferry Terminal at Pier 79 on Manhattan’s west side was constructed just 60 feet above the three tubes of the Lincoln tunnel. The project involved driving of pipe & sheet piles for the new ferry terminal and docking facilities. Some of the pipe piles were driven within 15 feet of…
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Dulles Airport Work 2003 The Automated People Mover project at Dulles International airport involved nearly two miles of tunneling. Large excavations were required for stations at the main terminal and the three mid-field terminals. The station at the main terminal involved a 50-foot cut and extensive underpinning of the terminal. Monitoring Requirements Monitor support of…
Read MoreRetaining Wall Failure
Castle Village Wall Failure 2005 When the Castle Village retaining wall failed, 41,000 cubic yards of rock, soil and trees slumped onto a major urban highway. The failure closed the highway and endangered nearby apartment buildings. The photo above shows the scale of the failure, some months later. The highway has been reopened, debris cleared,…
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LA Outfall Sewer Project Overview The Lower North Outfall Sewer served as one of Los Angeles’ primary wastewater tunnels for more than 70 years, but inspections revealed that the nine-mile long tunnel was at the point of failure at several locations. Corrosion had reduced the original 14-inch thick lining to just a few inches, and…
Read MoreBear Mountain Bridge
Bear Mountain Bridge Project Overview Bridge engineers added “helper” strands on this 1924 suspension bridge to counter load shedding by the main suspension cables. GEO-Instruments installed special strain gauges on the helper strands and anchors. These would be used to monitor the performance of the helper strands and to detect any further load shedding of…
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