Fiber Optics Geotechnical Instruments

Between 2012 and 2019, YieldPoint offered on a research and commercial basis the world’s highest resolution strain monitoring solution, using optical fiber for a much more detailed understanding of complex geomechanic phenomena in Mining or Civil projects. This innovative geotechnical monitoring solution is based on Rayleigh backscatter of light along a single standard telecom optical fiber. Four years of intensive Research and Development resulted in a combination of physical solutions and technical expertise that could be applied to the most complex problems in geomechanics. For example, YieldPoint was able to monitor the 3-D phenomena of shear deformation in rock, not only locating the exact depth of a shearing plane along a borehole in the rock but also determining the exact direction of that movement. YieldPoint could also accurately study multiple shear situations on systems several meters in length. 2 universities, one Canadian and one American, plus the Royal Military College and a large tunnel project in Australia have already taken advantage of this unique and progressive technology. YieldPoint was at inception of seminal work in this area but decided a few years ago to focus on digital instruments.

The standard optical products that YieldPoint has developed can be divided into three application categories:

The distribution of axial strain during a double shear test

Prof. Doug Milne at the University of Saskatchewan is using DOS technology to conduct monitoring of rebar in Potash mines. The UofS team have been installing optical reabars into underground potash mines where they expect the bolts to be subjected to interbed shearing.

An optical rebar installed in a US coal mine.