Non-linear elastic model incorporating temperature effects

Abstract

The objective of this paper is to present a non-linear elastic model, considering temperature effects, that engineers can readily use to predict the mechanical behaviours of soils in geotechnical applications. Instead of using hyperbolic and exponential models, a non-linear equation is first formatted to describe the tangent moduli for saturated clays by introducing only one additional parameter (i.e. p). By extending the non-linear equation, a new simplified nonlinear elastic model is obtained that is capable of capturing well the stress-strain relationship of saturated clays at room temperature. Thereafter, based on experimental results, the relationships between cohesion, internal friction angle, index, tangent bulk modulus and temperature are developed and incorporated in the non-linear elastic model. A revised semi-regression method is also developed to determine the relationship between the additional model parameter p and temperature. In this model, all of the eight parameters for the model have clear physical meanings and could be readily obtained by performing temperature-controlled triaxial tests. The accuracy and general applicability of the proposed method was checked by comparing its predictions with experimental results on saturated clay under various stress-path and temperature conditions as well as existing solutions proposed elsewhere.