GEO-Instruments Application Notes

A 210 ft span in the middle of a 1,000 ft retaining wall collapsed onto a major urban highway, closing the northbound travel lanes with over 41,000 cubic yards of rock, soil and trees. Following the emergency response to stabilize the slump and reopen travel lanes, a long term solution to the wall collapse was needed. A decision was made to excavate the failed section and rebuild with a Bin Wall; however, there were serious concerns regarding the stability of the remaining sections of wall during this process. All parties realized early on that a wall movement early warning system was crucial to the safe execution of this project. Geo-Instruments worked with the project geotechnical engineer to develop an automated monitoring system providing real time monitoring of the remaining walls.

A deep excavation at Dulles International Airport was needed in order to build a new terminal related infrastructure, and to facilitate tunneling operations connecting to the main terminal. In order to allow safe construction to continue inside the excavation, Airport management required that the support of the excavation system be monitored for movements with In Place Inclinometers.
Geo-Instruments supplied over 450 vertical IPI sensors, installed in over 40 inclinometer casings, connected to 6 remote dataloggers. Data is collected for the loggers hourly by a Geo-Instruments server, processed and displayed on a project website for the concerned parties to view. Real time e-mail alarms can also be accommodated in this system.