Behaviour of saturated sand under cyclic loading: Model approach with experimental validation

Abstract

This study presents a comparison between triaxial test results and constitutive model simulations for saturated sand subjected to a wide range of stress, relative density and both monotonic and cyclic loadings. This is a preliminary part of a project which is focussed on developing models for the behaviour of unsaturated soils under cyclic loading. There are currently limited experimental data of the cyclic behaviour of unsaturated soils due in part to the difficulty of controlling stress state, degree of initial saturation and uniformity of samples in experiments and their interpretation is challenging due to the mathematical complexity in constitutive models. This study attempts to bridge the abovementioned gap by creating an experimentally validated constitutive model for dynamic loading on saturated sand and then to extend this for unsaturated sands. The paper reports results from a series of monotonic triaxial tests and cyclic triaxial tests on saturated sand. Specimens of 100mm diameter, 200mm height and 54mm diameter, 110mm height have been prepared with different void ratios. These samples have been subjected to a wide range of deviatoric stress in both monotonic and cyclic tests. The results from these tests on saturated Sydney sand are presented and used to demonstrate the ability of the constitutive model. As the constitutive model has been developed for variable saturation demonstration of its success with saturated sand for which considerable data is available is the first stage in simulating the cyclic behaviour of the unsaturated sand.

Keywords

• saturated sand
• cyclic behaviour
• triaxial tests
• constitutive model