岩石材料局部化渐进剪切破坏特性及模型分析

Model Analysis on Localized Progressive Failure of Rock Material

为研究岩石材料局部化渐进剪切破坏过程和机制,利用RMT-150C岩石力学多功能试验机,对典型岩样进行三轴压缩试验,分析了岩石全应力应变过程,重点探讨应力软化、残余应力稳定2个峰后阶段,研究了岩石的破坏形式及机理.结果表明,应力在峰后阶段呈现渐进式跌落,并逐渐趋于稳定而达到残余强度.同时,基于局部化剪切带的形成过程,依据岩石应变软化机制,构建能模拟岩石渐进剪切破坏的力学模型.最后,对所建立的模型进行试验验证,模型计算与试验结果吻合较好,证明了该模型的合理性.

Triaxial compression experiment was carried out to investigate localized progressive failure mechanism of rock material by rock mechanics test equipment RMT-150C. Based on the experimental results, the complete stress-strain relation was analyzed, post-peak tow phases of stress-strain curve were discussed, and the failure mechanism of rock material was studied. The results show that the stress at post-peak stage occur a progressive fall, tend to stability and reach the residual strength. At the same time, the model which can simulate the process of strain softening and localize progressive failure is established, in virtue of the formation process and mechanism of localization shear zone. Finally, the results calculated through aboved model agree well with the experimental results,which prove the model is reasonable.