Matric Suction and Deformation Behavior of Unbound Granular Base (UGB) Materials under Constant and Variable Cell Pressure

Abstract

In the laboratory, generally cyclic triaxial tests are performed either with a constant confining pressure (CCP) or with a variable confining pressure (VCP). CCP and VCP tests are commonly assumed to deliver similar test results as long as the average cell pressure is the same. However, this assumption is based on the limited number of test data in the literature. Therefore, this study is designed to evaluate the effect of stress paths (i.e. CCP & VCP) on the matric suction and deformation behavior of unbound granular base (UGB) materials. A series of cyclic triaxial tests with different stress path are performed to isolate the effect of stress path on the deformation behavior of UGB materials. The evaluation of matric suction and the mechanical behavior of the UGB materials under different stress path are systematically studied.