In this paper, an overview of optical sensor development, testing and evaluation for several geotechnical monitoring
applications is presented. Additionally, sensor integration and data interpretation are addressed as key influences to the
overall success of the monitoring project. They should be taken into consideration already in the design stage.
Particular focus is given on strain sensor development to minimize the slippage of the fiber inside the protection. For the
first time, slippage progression monitoring by high spatially resolved Brillouin measurements is presented as a new tool
for sensor testing and evaluation for geotechnical projects.
The main findings of the study are that in a geotechnical monitoring project, special care has to be taken by choosing the
sensor slippage properties, longitudinal stiffness and robustness, as well as in the design of the sensor system itself
(fixation, gauge length and bond strength). With appropriate alignment of these factors, reasonable monitoring data can
be obtained, as shown in the applications proposed in this manuscript.