Research tools for direct shear of geomaterials contact surfaces with strain softening constitutive characteristics is more limited

based on FLAC

strain softening constitutive contact element models is achieved in this paper. Using this element models

the direct shear tests are simulated; the relationships between the shear strength parameters evolution for contact elements and the formal features of shear stress-displacement curves are deeply studied. The progressive failure process of the contact surfaces and the variation characteristics of the internal shear stress are reproduced in the simulation results. The studies have shown that the variation of the friction angle has a major impact on the formal features of shear stress-displacement curves.