考虑岩体强度各向异性的非线性单弱面破坏准则

Nonlinear Single-weak Plane Failure Criterion Considering Anisotropy of Rock Mass Strength

摘要:

提出一个新的、由节理面倾角引起的、岩体强度各向异性的、横观各向同性岩石的、非线性单弱面破坏准则。新准则建立在岩体两种不同的破坏模式基础之上：（1）滑移模式，即沿节理面滑移破坏；（2）非滑移破坏，即由岩石材料控制，与节理面无关。采用考虑节理面粗糙度的非线性强度准则描述滑移破坏模式的强度，确定该准则需要三个参数；采用可考虑由节理面倾角引起的岩石强度各向异性的Hoek-Brown准则描述非滑移破坏模式的强度，确定该准则需要四个参数。详细阐述各参数的取值方法，采用文献中的试验数据验证新准则的准确性，并与Jaeger单弱面理论的计算结果进行比较，验证新准则的试验数据包括岩石的不同围压条件及不同节理倾角。节理倾角对岩石强度的影响随着围压的增加而逐步降低。

Abstract:

A new nonlinear single-weak plane failure criterion is proposed, caused by the inclination angle of the joint plane, and considering the anisotropic in strength and isotropic in transverse view of rock mass. The new criterion is based on two different failure modes of rock masses: (1) sliding mode, that is, sliding failure along the joint plane, and (2) non-sliding failure, that is, controlled by the rock material, has nothing to do with the joint plane. The strength of the sliding failure mode is described by using a nonlinear strength criterion considering the roughness of the joint plane. Three parameters are required to determine this criterion. The strength of the non-sliding failure mode is described by using the Hoek-Brown criterion able to consider the anisotropy of rock strength caused by the inclination angle of the joint plane. Four parameters are required to determine this criterion. The methods for taking values of each parameter are elaborated in detail. The accuracy of the new criterion is verified by using the experimental data in the literature, and is compared with the calculation results of Jaeger simple-weak plane theory. The test data of the new criterion are verified including the different confining pressure conditions of rocks and different joint inclination angles. The influence of joint inclination angle on rock strength gradually decreases with the increase of confining pressure.