SHEAR TEST OF JOINT AND ANALYSIS OF MORPHOLOGY CHARACTERISTIC EVOLUTION OF JOINT SURFACE
(1. School of Resources and Safety Engineering，Central South University，Changsha，Hunan 410083，China；
2. Kunming Prospecting and Design Institute of China Non-ferrous Metals Industry，Kunming，Yunnan 650051，China)
Abstract：The morphology of joint surface is one of the key factors affecting shear strength of joint. Relationships between morphology of joint surface and shear strength of joint are studied experimentally. Shear tests of natural rock joint under different normal stresses are conducted with RYL–600 rock shear-rheological instrument，and the relationships between shear stress and shear displacement under different normal stresses are obtained. Topographical measurements are carried out prior to and after shear tests with TALYSURF CLI 2000；3D scanning images of joint surface are obtained. Relationships between shear strength of joint under different normal stresses and morphology characteristic evolution of joint surface is analyzed. The weighted average of the mean profile angles of rock joint surface is firstly computed. It is found that the peak shear strength increases with normal stress；and the average of the mean profile angles decreases with the increase in the number of times of shear tests. It is shown that the shear strength of joint is concerned with normal stress and weighted average of mean profile angles of joint surface.
2011, Vol. 30 
