Development of a wireless sensor unit for tunnel monitoring

Abstract

In this thesis we describe the development of a wireless sensor module for tunnel monitoring. The tunnel in question is a part of the London Underground system. Construction of a new tunnel beneath the existing tunnel is anticipated to cause quantifiable vertical displacement. To ensure safe operation of the tunnel during the construction activity, a real-time monitoring system has been created to measure vertical displacements along the critical zone near Highbury & Islington station. A geomechanical analysis, provided by a third party, is used to establish the allowable maximum displacement. A custom wireless sensor module was developed from off-the-shelf components. This module consists of a sensor device, microcontroller, ADC and RF transmitter. The integration of these components is described in detail. Deployment details and some preliminary results are presented.