Effect of temperature on behaviour of red clay-structure interface

This study presents the results of an experimental investigation conducted to assess the temperature effects on shear stress-strain behaviour and shear strength parameters of red clay and its interface with the geostructure under different normal stresses (50, 100, 200, and 400 kPa). A modified direct shear test apparatus, capable of handling temperatures up to 50 degrees C, was used in this study. The experimental program includes shearing the red clay and red clay-structure interface at different temperatures (2, 15, 38 degrees C) and after subjecting it to different heating-cooling cycles. The test results in this study and the previous studies in the literature indicated that the temperature has insignificant effects on the friction angle of clay and clay-structure interface. However, the temperature effect on the cohesion of clay and the adhesion between the clay and structure depends on the normal stress level and history. A new conceptual understanding for the possible temperature effect on the clay-structure interface was introduced in this study and it was used to interpret the different interface test results in the literature.