深部岩体强度准则

提出一种新的适用于深部岩体的强度准则,该准则考虑深部岩体的拉伸破坏,同时考虑深部岩体的剪胀和剪缩破坏,其破坏面可以是闭合的也可以是张开的,而且与RMR岩体地质力学分类指标建立联系.深部岩体准则中的参数均有明确的物理意义,可以很容易通过实验确定或通过RMR岩体地质力学分类确定.该准则不仅可考虑所有应力分量对材料破坏的影响,而且可反映深部岩体的受力特点.最后,将新准则与实验结果进行比较,从而验证了新准则的有效性.

STRENGTH CRITERIA OF DEEP ROCK MASS

The most distinguished difference between deep and shallow levels is the so-called high geostress.The failure mode of the shallow rock mass is brittle failure.The failure modes of the deep rock mass may be brittle failure or ductile failure that depend on the property of rock mass and the geostress state.Mohr-Coulomb criterion,Hoek-Brown criterion,Druck-Prager criterion and unified strength criterion are suitable for brittle failure of the shallow rock mass.A new strength criterion,which is applicable to deep rock mass,is proposed.The new strength criterion,in which the effect of intermediate principal stress is considered,can consider the brittle failure and ductile failure of the deep rock mass.Moreover,the new strength criterion that is relative to the rock mass rating(RMR) classification can be applied to the research of the tensile failure of deep rock mass.All the parameters have clear physical concept,which can be conveniently determined by experiments or RMR in the presented criterion.Finally,in order to examine the proposed strength criterion,the comparison between the present strength criterion and the experimental data is performed.It is shown that the presented strength criterion is in good agreement with the experimental results.