Abstract : Wireless Sensor Network - Based Tunnel Monitoring ∗

In this paper we describe the development and deployment of a wireless sensor network (WSN) to monitor a train tunnel during adjacent construction activity. The tunnel in question is a part of the London Underground system. Construction of tunnels beneath the existing tunnel is expected to cause deformations. The expected deformation values were determined by a detailed geotechnical analysis. A real-time monitoring system, comprising of 18 sensing units and a base-station, was installed along the critical zone of the tunnel to measure the deformations. The sensing units report their data to the base-station at periodic intervals. The system was used for making continuous measurements for a period of 72 days. This window of time covered the period during which the tunnel boring machine (TBM) was active near the critical zone. The deployed WSN provided accurate data for measuring the displacements and this is corroborated from the tunnel contractor’s data.