三轴压缩大理岩局部化变形的试验研究及其分岔行为

常规三轴压缩过程 ,岩石试件破坏常常是以狭窄剪切带形式存在的局部化变形为先导。结合常规三轴压缩试验 ,对大理岩破坏过程中局部化变形的发展过程进行研究 ,其结果表明 :岩石局部化变形分为三个阶段 ,即稳定阶段、稳定增长阶段和快速发展阶段 ;局部化变形在体积膨胀点之前开始稳定增长 ;达到一定程度后 ,岩石表现出短暂的应变硬化 ,岩石开始剪胀。最后应用对称性群论分岔理论对此过程中的滑移线等分岔现象进行了初步研究

Experimental studies on localization and bifurcation behaviors of a marble under triaxial compression

The failure of rock under triaxial compression is due to the localization of narrow shear band. Based on triaxial compression tests, local strains of a marble specimen are measured in present paper so as to study the development of the localization during the failure of specimens. Experimental results showed that the process of failure could be divided into three stages, that is steady stage, steady increase stage and quick development stage. The localization began to steadily increase before the volume of specimen dilated. When it accumulated to a higher degree, the specimen began to shear and dilate after a short time of strain hardening.A preliminary analysis of the bifurcation behaviors discussed above (sliding lines et al.) was conducted in the application of symmetric groups bifurcation theory.