Listening for deterioration and failure: Towards smart geotechnical infrastructure

Global change is accelerating the rate of deterioration of geotechnical infrastructure systems. There is an urgent need for monitoring strategies that can be used to assess existing, ageing infrastructure through retrofitting sensors at discrete locations to detect and provide early warning of limit state failures. This paper describes a novel approach for smart geotechnical infrastructure that ‘listens’ to acoustic emission (AE) generated by geotechnical asset deterioration and failure. AE rates generated by geotechnical systems have been proven to be proportional to deformation rates. AE is becoming an accepted monitoring technology for geotechnical applications; however, challenges still exist to develop widely applicable AE interpretation strategies. This paper places AE geotechnical monitoring in a smart infrastructure context and presents: the key factors influencing AE propagation and attenuation in buried structural elements; techniques for quantifying AE parameters; and AE interpretation frameworks for extracting information and knowledge on the deformation and strength behaviour of geotechnical infrastructure systems. AE interpretation strategies for exemplar applications (e.g. slopes, pile foundations and buried pipelines) are developed and demonstrated through element- and large-scale experiments and field trials.