Anisotropic Creep Test of Greenchist Under Uniaxial Compression

Abstract:

The uniaxial creep tests of green schist from auxiliary tunnel at Jinping second stage hydropower station were carried out.An analysis was made of the influence of relationship between axial loading orientation and bedding plane on instantaneous strain,stress strain relation,axial strain rate,time duration of transient creep phase and creep breach mechanism.The instantaneous strain increment when axial loading orientation is perpendicular to bedding plane is larger than that when parallel to bedding plane under the same lower stress level,while,the result is on the contrary under the same higher stress levels.The axial strain rate and time duration of transient creep phase when axial loading orientation is perpendicular to bedding plane is smaller than that when the parallel to bedding plane under the same stress level.Meanwhile,the stress strain relation curve has initial crack closing stage,elastic deformation stage,crack extending stage and post failure stage when axial loading orientation is perpendicular or parallel to bedding plane,and the creep failure patterns under two kinds of conditions are both brittle.

Key words:green chist; uniaxial compression; creep test; hydropower station; bedding