A Temperature Controlled Triaxial Apparatus for Testing Unsaturated Soils

This paper describes a modified Bishop–Wesley triaxial apparatus for testing unsaturated soils at elevated temperatures. The suction is applied using the axis translation technique. The cell liquid temperature is controlled through a heating element, and a thermal sensor installed inside the triaxial cell. Experiments are carried out at temperatures up to 60°C. Potential difficulties in the use of the equipment are identified and solutions are discussed for their mitigation. The image-processing and the cell liquid measurement techniques are used to measure the overall volume change of the sample. The performance of these two techniques is reported.

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