A Study for Degradation of Joint Asperity

Shear behavior of joint plane has been investigated by considering the level of normal stresses and initial surface roughness. For research about degradation in estimated joint planes, this study has been measured by performing the multi-stage shear test in which applied normal stress level has been increased stepwise. Specimens in used the test have been composed by three rock type, gneiss, granite and shale, under the Ai- 20 level. After the shear test, the asperity variation each rock type has been measured and influence of normal stress and initial surface roughness on sequential shear test has been analyzed.