The application of distributed optical strain sensing to measure the strain distribution of ground support members

FACETS

Nicholas Vlachopoulos¹  Bradley Forbes²  Andrew J. Hyett³ 

[1] Department of Civil Engineering, Royal Military College of Canada, Kingston, ON K7K 7B4, Canada.;Geological Sciences and Geological Engineering Department, Queen’s University, Kingston, ON K7L 3N6, Canada.;YieldPoint Inc., Kingston, ON K7M 4W9, Canada.;

关键词: distributed optical strain sensing;    ground support;    rock bolt;    cable bolt;    strain measurement;   

DOI  :  10.1139/facets-2017-0093

来源: DOAJ

【 摘 要 】

A distributed optical strain-sensing technique is presented as a solution for measuring the strain distribution along ground support members used in tunnelling and mining works. The technique employs a Rayleigh optical frequency domain reflectometry technology, which measures strain at a spatial resolution of 0.65 mm along the length of a standard optical fiber. A rationale for selecting this technology as a potential monitoring technique for ground support elements over alternative commercially available technologies is discussed. The development of a technique to couple optical fiber sensors with rock bolt, umbrella arch, and cable bolt support members is also demonstrated. A robust laboratory investigation of such optically instrumented support members demonstrated the capability of the technique to capture the expected in situ support behaviour in the form of coaxial, lateral, and shear loading arrangements as would be anticipated in the field. Moreover, the micro-scale data obtained by this optical sensing technique are shown to provide unprecedented insight into the local/micro-scale geomechanistic complexities associated with the bearing capacity of ground support members, especially when compared with data obtained by discrete strain-sensing technologies.

【 授权许可】

Unknown