Experimental Evaluation of Shear Strength of Kaolin Clay under Cyclic and Noncyclic Thermal Loading

The soil response to daily temperature variation imposed by an energy pile is critical for estimating the energy pile's capacity and serviceability. It is, therefore, necessary to determine the temperature-induced effects on mechanical properties of soils. This article presents the results of an experimental study on the effects of thermal loading on shear strength of reconstituted kaolin clay. The study was performed using a triaxial testing apparatus capable of applying thermal loading. Different cyclic and noncyclic thermal loadings, with temperatures ranging between 24 degrees C and 34 degrees C, were applied. In addition, two theoretical mechanisms defining force distribution at the interparticle level were used to analyze the shearing behavior of clay under thermal loading. Both experimental and theoretical results indicate that the influence of temperature variation on the shear strength of clay is primarily controlled by stress state and stress history.