POST-PEAK DEFORMATION AND FAILURE EXPERIMENTAL STUDY
OF ROCK-LIKE SPECIMENS WITH DIFFERENT INCLINATION
ANGLES PERSISTENT JOINTS
LI Shuchen1，WANG Lei1，2，LI Shucai1，HAN Jianxin1，3
(1. Geotechnical and Structural Engineering Research Center，Shandong University，Jinan，Shandong 250061，China；2. Institute of Engineering Corps，Three Lines，Xuzhou，Jiangsu 221004，China；3. School of Mathematic and Quantitative Economics，Shandong University of Finance and Economics，Jinan，Shandong 250014，China)
Abstract：The uniaxial compression test of pre-existing persistent jointed rock-like specimens is carried out by high stiffness servo control testing machine. Systematic researches on the relationship of post-peak stress-strain curve，failure form，strength after peak，the Poisson?s ratio after peak of rock masses with dip angles of persistent joints are performed. The results indicate that：(1) The post-peak stress-strain curves of specimens with joint inclination angle of 15°and complete specimens are basically the same，but the post-peak stress-strain curves of specimens with the joint inclination angle of 30°，40°，50° to 60° and complete specimens vary greatly. (2) Peak strength decreases with the increase of joint inclination angle，residual post-peak strength also generally increases as the joint angle increases. (3) Poisson?s ratio of jointed specimen increases with joint inclination angle increases，but the post-peak visual Poisson?s ratio becomes smaller in the phase of destruction with joint inclination angle increases. (4) The post-peak failure modes of specimen change with joint inclination angle. Specimens damage is splitting failure at the joint inclination angle of 15°，shear failure at the joint inclination angle of 50° and 60°， splitting and shear mixing model at the joint inclination angle of 30° and 40°. The research result can reflect mechanics，deformation and damage characteristics under uniaxial compressive loading in the phase of post-peak of rock masses with different dip angles pre-existing persistent joints.
2013, Vol. 32 
