A Novel Approach to Surface Strain Measurement for Cylindrical Rock Specimens Under Uniaxial Compression Using Distributed Fibre Optic Sensor Technology

This study proposes a novel approach to surface strain measurement for cylindrical rock specimens subjected to uniaxial compression using distributed fibre optic sensing technology. The capability and accuracy of this approach in measuring the full-field strain distribution of a rock specimen have been verified by a series of uniaxial compressive strength (UCS) tests on cylindrical specimens of aluminium alloy, sandstone, and granite. By analysing the experimental results, this new approach also has the potential of being utilized to detect the potential failure locations and sequence through strain localization zone variations and estimation of the development of crack opening displacement and rock fracturing characteristics during the loading and unloading process. Detailed installation procedures are provided for this study for assistance in the use of this new approach. The boundary issue of fibre measurements is identified, and solved by extending the bonding length of the measuring fibre.

Automated summary

A novel approach utilizing distributed fibre optic sensing technology for surface strain measurement on cylindrical rock specimens under uniaxial compression is proposed. The approach has been validated for accuracy through UCS tests on various materials and shows potential for detecting failure locations and crack development characteristics. Detailed installation procedures and resolution of boundary issues for fibre measurements are provided in the study.