%0 Journal Article
%T A custom acoustic emission monitoring system for harsh environments: application to freezing-induced damage in alpine rock-walls
%A L. Girard
%A J. Beutel
%A S. Gruber
%A J. Hunziker
%J Geoscientific Instrumentation, Methods and Data Systems Discussions
%D 2012
%I Copernicus Publications
%R 10.5194/gid-2-267-2012
%X We present a custom acoustic emission (AE) monitoring system designed to perform long-term measurements on high-alpine rock-walls. AE monitoring is a common technique for characterizing damage evolution in solid materials. The system is based on a two-channel AE sensor node (AE-node) integrated into a Wireless Sensor Network (WSN) customized for operation in harsh environments. This wireless architecture offers flexibility in the deployment of AE-nodes at any position of the rock-wall that needs to be monitored, within a range of a few hundred meters from a core station connected to the internet. The system achieves near real-time data delivery and allows the user to remotely control the AE detection threshold. In order to protect AE sensors and capture acoustic signals from specific depths of the rock-wall, a special casing was developed. The monitoring system is completed by two probes that measure rock temperature and liquid water content, both probes being also integrated into the WSN. We report a first deployment of the monitoring system on a rock-wall at Jungfraujoch, 3500 m a.s.l., Switzerland. While this first deployment of the monitoring system aims to support fundamental research on processes that damage rock under cold climate, the system could serve a number of other applications, including rock-fall hazard surveillance or structural monitoring of concrete structures.
%U http://www.geosci-instrum-method-data-syst-discuss.net/2/267/2012/gid-2-267-2012.pdf