GEOTECHNICAL INSTRUMENTATION FOR MONITORING TUNNELING/EXCAVATION OPERATIONS DART LIGHT RAIL TRANSIT SYSTEM DALLAS, TEXAS
Mark J. Farrow, P.E.1 & Terry W. Oswald, P.E.2
The DART light rail transit system will provide the public with quick and easy access to downtown Dallas' Central Business District (CBD). The majority of the 20-mile transit system will be above ground with ground level stations, including the CBD Transit-way Mall in downtown Dallas. A 3.5 mile section of the light rail system extending beneath Central Expressway, from Dallas' CBD to Mockingbird Lane, will consist of two subway tunnels (with an underground station), bored through the Austin Chalk Limestone at depths up to 130 feet.
A comprehensive geotechnical instrumentation monitoring system was installed for early detection of ground movement during tunneling activities and construction of DART’s light rail transit system.
Instrumentation for these projects included Inclinometers, Borehole Extensometers, Deep Benchmarks, Piezometers, Vibrating Wire Piezometers, Concrete Pressure Cells and Ground Load Cells. This paper presents an overview of the geotechnical instrumentation implemented for the DART projects.
