Experimental investigation and field application of acoustic emission array for landslide monitoring

Landslide deformation monitoring is an important method for proactive disaster prevention. Acoustic emission (AE) equipment, comprising active waveguides (i.e., a steel tube with granular internal/external backfill), has become an optional monitoring technology for subsurface deformation in landslides. It is also challenging to develop novel AE monitoring equipment that can optimise technological applications and data interpretation. In this study, we developed an equipment named “AE array” with a newly designed assembly and a standardised structure, from which we developed a complete AE monitoring system. We then conducted an experimental investigation of the AE array using speed-controlled compression to explore the acoustic properties in response to deformation. The AE array was also used in the field to demonstrate its practical use and performance for landslide monitoring at a loess slope. The deformation–AE relationship was obtained and compared using data from the compression experiment and the field site. The AE array collectively monitored AE and an inclinometer within a borehole, which has practical applications and data validation advantages. A strong linear correlation was obtained between the cumulative displacement and AE data, independent of the length of the AE array. The complexity and variability of the field-based deformation–AE relationship have implications for potentially improving the performance of the AE array. Machine learning models should be considered to automatically quantify the dynamic deformation–AE relationship, which can provide a basis for landslide early warning systems.