Anisotropic shear behavior of rock joint based on 3D printing technology

Topography is an important factor affecting the shear behavior of joint. Furthermore, there are certain connections between the anisotropy of topography and the anisotropy of shear behavior. In this study, 3D laser scanning technology and 3D printing technology were used to make molds for simulating the topography of natural joint. Then, the cement mortar samples with dimension of 100 mm×100 mm×150 mm were cast, and shear tests with different shear directions under different normal stresses were conducted. The results indicate that obvious anisotropy has been shown in the joint shear behavior, which is reflected in the peak shear strength and the corresponding shear displacement and shear strength parameters, respectively. In addition, the anisotropy of the peak shear strength do not present simple monotone to the normal stress under low normal stress. The shear strength parameters c and ϕ with different directions both show significant anisotropy, and the values of them have similar variation tendency. What's more, the results also indicate that the shear direction has a stronger influence on the cohesion by analyzing the discrepancy of cohesion and internal friction angle compared to 0°.