双剪双参数统一强度准则改进式及其应用
( 福州大学 土木建筑工程学院,福州 350002)
摘 要: 通过应力莫尔圆分析发现,现有的双剪双参数统一强度准则在形式上可看成是对具有直线型强度包络线的Mohr-Coulomb强度准则的改进,适用于对具有线性强度包络线的岩石作力学分析。对具有抛物线型强度包络线的岩石,通过对现有的双剪双参数统一强度准则作相应的非线性化处理,导出了具有该类型强度包络线的双剪双参数统一强度准则改进式,改进式可用于对承受高压的硬岩和软岩作强度分析。另外,还应用改进式对静水压力条件下圆形巷道围岩作了弹塑性分析。
关键字: 双剪双参数统一强度准则;抛物线型强度包络线;巷道围岩;弹塑性分析
( School of Civil Engineering and Architecture,
Fuzhou University, Fuzhou 350002, China)
Abstract: The Mohr circle comparisons show that the two-parameter twin shear unified failure criterion used now has the linear type of the failure envelope as the same as the Mohr-Coulomb strength theory, and it is applicable to the rock with the linear type of the failure envelope. For rock with the parabolic form of the failure envelope, the nonlinear improved expression of the two-parameter twin shear unified failure criterion was given out, and this improved failure criterion could be used to analyze the hard rock bearing high pressure and the soft rock which failure envelopes usually take the form of parabolic. In spite of the above work, the elasto-plastic analysis with this new improved failure criterion is applied to the wall rock around the tunnel with circular cross-section under the static hydraulic pressures.
Key words: two-parameter twin shear unified failure criterion; parabolic failure envelope; wall rock around tunnel; elasto-plastic analysis