projects
Dulles Airport
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 MoreReconstruction of Retaining Wall
Reconstruction of a Failed Retaining Wall 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. Image courtesy of Michael Minn The photo above, taken some months later, shows the scale of the failure.…
Read MoreLA Outfall Sewer
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…
Read More