横观各向同性岩石类材料的破坏准则

对岩石类材料，各向异性状态参数定义为材料微观结构偏张量与标准化的偏应力张量之间的联合不变量。通过在扩展的Lade-Duncan破坏准则内耦合各向异性状态参数，建立起了横观各向同性岩土类材料的破坏准则，并结合Tournemire页岩的三轴试验资料进行了验证工作。当加荷方向与材料沉积方向的夹角 在30°~60°范围时，预测出的岩石强度处于最小区域，从而达到了较好地对横观各向同性岩石的破坏强度进行合理预测的目的。

FAILURE CRITERION FOR TRANSVERSELY ISOTROPIC ROCK MATERIALS

For rock materials,a transversely isotropic failure criterion,established through the extended Lade-Duncan failure criterion incorporating an anisotropic state scalar parameter which is a joint invariant of deviatoric microstructure fabric tensor and a normalized deviatoric stress tensor,is verified by Tournemire shale triaxial compressive testing data.When the angle between the loading direction and principal direction of the transversely isotropic microstructure of rock material is changed from 30° to 60°,corresponding lower failure strengths are predicted,which is agreed with testing results.These predicting results show that the transversely isotropic failure criterion is reasonable.