Title Experimental Study on Shear Characteristic of Filling Rock Joints Under Constant Normal Load Conditions

摘要

Cubic saw-tooth specimens are made by using cement mortar filled with material. Considering the effects of different factors stress on the mechanical properties of rock, three factors are considered in this paper: three kinds of filling degrees (0,0.5,1), three kinds of asperity angles (25°,40°, 55°), two kinds of filling material(white cement, gypsum). The direct shear test is carried out under different normal stresses (30kN,50 kN,80 kN,120 kN). The results indicated that, when the normal stress is low, the peak shear strength of white cement filling and gypsum filling no obvious difference. The peak shear strength for filled joints decreases with the increase of filling degree. The asperity angle is in direct proportion to the peak shear strength. Besides, the normal stress is in direct proportion to the peak shear strength. In addition, three factors (filling degree, asperity angles and filling material) play an important role in the failure mode.