Study on softening constitutive model of Malan loess

Abstract

In this paper, based on the uniaxial compression tests, consolidated undrained shear tests, consolidation drainage shear tests of Malan loess with different water contents, and based on understanding deeply of peculiar physico-mechanical property of Malan loess, the properties and physical meanings of stress-strain curves of Malan loess were analyzed, and softening constitutive model of Malan loess was proposed. The model can be used to describe accurately stress-strain of Malan loess which axial strain was lower than 5%-6%, and disclosed mechanical behavior of Malan loess under lower strain, and it also provided theoretical basis for further study on other mechanical properties of Malan loess. At the same time, variations of parameters from softening constitutive were analyzed. It was shown that parameters a and b were all functions of water contents (ω) and confining pressures (σ3), which had some certain change patterns.