Performance of an acoustic emission monitoring system to detect subsurface ground deformations at Flat Cliffs, North Yorkshire, UK

This paper describes the performance of an innovative acoustic emission subsurface slope displacement monitoring system installed in a large coastal landslide complex at Flat Cliffs, North Yorkshire, northeast England. Cliff instability is indicated by repeat deformation of an access road that serves a settlement of about 50 houses. As part of an extensive ground investigation, a sensor that can quantify acoustic emission was installed adjacent to a standard inclinometer, and continuous monitoring of acoustic emission has since taken place. The acoustic sensor has detected periods of slope deformation that are confirmed by manual surveys of the inclinometer. Performance is demonstrated using time series of acoustic measurements compared with ground deformations and triggering rainfall events.