ANALYSIS OF SHEAR ZONE DEFORMATION BEHAVIOR IN COARSE-GRAINED SOIL BY LARGE SCALE DIRECT SHEAR TEST

The large scale direct shear test system includes overlaying rings that are the important component of shear box. Multiple sets of shear surfaces can be formed according to the structure of coarse-grained soil, which can reflect shear deformation characteristics clearly. In order to analyze the influence of coarse granules composed of hard rock material on the strength and deformation, the large scale direct shear test is made on coarse-grained soil. The coarse grain lithology is granite. The paper analyzes experiment laws and particle motion of the hard rock coarse-grained soil and finds that granitic coarse grains have a significant impact on the strength and deformation. Because of their hard rock lithology, granitic particles are not easy to be broken. In fact they mainly do the position adjustment and rolling motion. Staircase of shear displacement emerges in shear zone under low axial stress. Nevertheless, shear displacement in shear zone manifestations linear variation and more apparent dilatancy effect under high axial stress. The coarse-grained soil has high shear strength and stability after shearing failure. The results provides certain reference for engineering construction.