Experimental Study on Shear mechanism of Rock Discontinuities

本课题取得的主要成果如下：1。在恒定法向应力条件下对岩体结构面进行剪切试验后发现，结构面在高频区域的表面粗糙度比定义的表面粗糙度取决于正应力，其表面粗糙度是断裂的。随着剪切位移的推进，岩体结构面表面粗糙度的破坏发生在高频分量，并向低频分量发展。但在极限频率下，韧性的爬升取决于正应力。在一定位移下的抗剪强度取决于主要发生断裂的粗糙度成分的强度。在粗糙度发生爬升的情况下，抗剪强度保持不变。这对应于剩余强度。表面粗糙度的断裂不会发生，直到峰值抗剪强度出现。在峰值强度下，断口立即发育为一定程度的高频粗糙度。伴随剪切位移的正常扩张也取决于主要发生断裂的粗糙度分量，或粗糙度的极限爬坡频率。

Main results obtained in this project are following.1. It is observed that the surface roughness of discontinuities in the higher frequency region, than the defined one depend on the normal stress, are fractured, after the shear test of rock discontinuities under the condition of the constant normal stress.2. Progressing the shear displacement, the fracture of the surface roughness of rock discontinuities occurs in the high frequency components, and develops to the lower components. But the climb over the toughness occurs at the limit frequency depend on the normal stress.3. The shear strength at a certain displacement, depends on the strength of the roughness components, in which fracture is occurring mainly. In the case that the climb over the roughness occurs, the shear strength is kept constant. This corresponds to the residual strength.4. The fracture of the surface roughness does not occur, until the peak shear strength appears. At the peak strength, the fracture develops at once to the some extent of higher frequency roughness.5. The normal dilatation accompanied with the shear displacement, also depends on the roughness components in which fracture is occurring mainly, or the limit frequency of the climb over roughness.