Geo-Instruments – Support of Excavation Monitoring: What’s in the toolbox?Geo-Instruments –

Presented by: Emma Migneault

Excavations in urban environments require monitoring systems not only to verify that the support of excavation operates within design parameters, but also for managing risk to adjacent infrastructure. Instrumentation systems chosen for the necessary structural and geotechnical monitoring must be considered by what data will best allow for objective decision making over the course of the project. Once that is understood, the selection process can further narrow down sensor and system choice by additional factors such as installation considerations, site conditions and required frequency of data. Understanding all options for instrumentation, or what we can call the ‘toolbox’ of available monitoring systems, will allow for the optimal choice of implemented systems.

Instruments often used to monitor support of excavation systems include Automated Motorized Total Stations (AMTS), Tiltmeters, Shape Arrays, Piezometers and Strain Gauges. Options for monitoring of adjacent structures include AMTS, Crackmeters, hydrostatic level cells, Vibration monitors and pre- and post-construction survey. Taking into account the data deliverable needed, and the particulars of the monitoring system, the instrumentation program can provide design validation or early warning of trending movement.