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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.
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Received: 05 November 2012
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2013, Vol. 32 
