Laboratory investigations of the thermal strain of frozen soils, using fiber-optic strain gauges based on Bragg gratings

Abstract

Measurements of the thermal deformations of frozen soil samples were performed in the cold laboratory in temperature range from 0 °C to −12 °C. Fiber Bragg Gratings strain and temperature sensors were used to measure the deformation and temperature inside the samples. A number of tests with the samples prepared from Kaolin and Cambrian clay saturated with fresh water, and prepared from fine and silt sand saturated with fresh or saline water, are performed. Thermal deformations of the samples are analyzed depending on the cyclic changes of their temperature.