Distributed Brillouin Sensing for Geotechnical Infrastructure: Capabilities and Challenges

Abstract

Distributed Brillouin sensing has become a state-of-the-art tool for strain and temperature monitoring in concrete and geotechnical applications throughout the civil construction industry. While commercially available systems are steadily advancing in terms of spatial resolution and measurement length, end-users in field installations often put the focus on softer parameters like linearity or optical budget when evaluating the performance of the technology.
This paper addresses the implications of high spatial resolution to the accuracy of relative and absolute strain and temperature data from the perspective of the Brillouin optical frequency domain analysis (BOFDA) technology, and outlines the need for a clear definition and a standardization scheme to make the terms dynamic range and optical budget comparable between different instruments and technologies. Data from field applications in concrete pile monitoring is used to discuss the above aspects.