Behaviour and frequency characteristics of acoustic emissions from sandy ground under model pile penetration

Abstract

Acoustic emission (AE) testing is regarded as an effective non-destructive technique and is capable of detecting micro-level defects inside a material. In the field of civil engineering, the acoustic emission technique has been widely applied to the studies of steelwork, concrete, and composite materials. However, the geophysical investigations of the application of acoustic emission, dealing with porous granular media, are comparatively limited. In this study, the acoustic emission testing is implemented in a model pile system to investigate subsoil behaviour subjected to pile penetration. The results reveal that the tendency of acoustic emission settlement and load settlement shows high similarity. In addition, the detected acoustic emission signals are studied in the frequency domain using fast Fourier transformation. Higher frequency acoustic emission signals (>100 kHz) are interpreted to be associated with sand particle crushing, which provides a new insight to evaluate the feature of sand grain crushing. Furthermore, the distinction of acoustic emission characteristics observed among different pile penetration sequences demonstrates the effect of ground density on the subsoil behaviour. The results obtained in this paper are beneficial to further clarify the bearing mechanism of pile foundations and also to provide useful information on the fundamental characteristics of acoustic emission signals originating from stressed granular soils, that can be extended to other acoustic emission-based field investigations. tine methodology for process monitoring since only the end condi-

Relationship between acoustic emission and energy dissipation: a DEM study of soil–structure interaction

“…For slope monitoring applications, relationships between measured AE and slope deformation behaviour have been quantified, enabling early warning of accelerating slope movements and failure [13,40,48,49]. For pile monitoring applications, relationships between measured AE and load-displacement behaviour are developed [34][35][36]. For buried pipe monitoring, relationships between AE activity and pipe displacement in uplift and differential ground motion experiments have been established [50,52].…”

Acoustic Emission Sensing of Pipe–Soil Interaction: Full-Scale Pipelines Subjected to Differential Ground Movements

“…Koerner et al 1976;Koerner et al 1978;Koerner et al 1981;Koerner et al 1984;Mitchell and Romeril 1984;Tanimoto and Tanaka 1986;Garga and Chichibu 1990;Shiotani and Ohtsu 1999). Recent advances have been made in the interpretation of soil/structure interaction behavior from AE measurements using physical modelling and field experiments for slope instability (Smith et al 2014;Smith and Dixon 2015;Dixon et al 2015a;Dixon et al 2015b;Michlmayr et al 2017;Smith et al 2017a;Berg et al 2018;Dixon et al 2018) and pile loading (Mao et al 2015;Mao et al 2016;Mao et al 2018) applications.…”