Fibre Optic Monitoring in Geotechnics–Towards Safer Piles, Embankments, Dams, and Pipelines

Distributed Fibre Optic Sensing (DFOS) is increasingly applicable in civil and geotechnical engineering to monitor the structural performance during construction and operation. The technology allows for continuous measurement of strain, displacement, vibration, and temperature over the entire length of the sensor – which can extend to tens of kilometres. This makes DFOS technology particularly suitable for monitoring long (linear) geotechnical structures. However, this approach is not plug-and-play. In fact, each project requires an individual design in terms of selecting the sensor and interrogator parameters, installation procedure, compensation methodology, algorithms, and data visualisation techniques to facilitate engineering interpretation. This is why a better understanding of the possibilities and limitations of DFOS, based on practical examples and lessons learned, is of great importance to the industry community. The article briefly discusses four geotechnical cases, where different monolithic sensors were applied to monitor the concrete pile, road embankment, earth dam, and gas pipeline by measuring various physical quantities.

Keywords: Distributed fibre optic sensing, Monolithic sensors, Geotechnical monitoring, Pile load tests, Embankment, Dam, Pipeline.