化学腐蚀下花岗岩三轴压缩力学特性试验

摘要

利用岩石三轴测试系统对3种不同pH化学溶液浸泡后的花岗岩进行三轴压缩试验，探讨不同pH化学溶液对花岗岩力学特性的腐蚀效应，获得不同化学溶液对花岗岩强度和变形特性的影响规律。并通过测量3种溶液浸泡过程中各溶液的pH变化以及浸泡岩样的质量变化分析化学溶液对岩石的腐蚀程度。研究结果表明：不同pH化学溶液对花岗岩力学性质的影响不同，pH为10溶液浸泡后的花岗岩三轴压缩强度最高，pH为13溶液浸泡后的花岗岩三轴压缩强度次之，pH 为7溶液浸泡后的花岗岩三轴压缩强度最低，且花岗岩的凝聚力随差浸泡溶液的 pH 增加而增加，而内摩擦角随着 pH 增加而减少，并进一步分析化学溶液对花岗岩强度的腐蚀机理。室内试验结果可为构建花岗岩化学腐蚀条件下本构模型提供重要的试验资料。%A rock triaxial testing was used to conduct triaxial compression tests on the granites samples which were soaked in three chemical solutions with different pH. The effect of chemical solutions on the mechanical properties of granites was studied. The influence of chemical solutions on strength and deformation properties of granites was investigated. The corrosion degree was evaluated by measuring the variation of pH for three solutions and the variation of mass of soaked samples. The results show that the effects of three solutions on the mechanical properties of granite are different. The triaxial strength of granite is the highest in the case of pH=10, followed by that of pH=13 and it is lowest with pH=7. The cohesion of granite increases with the increase of pH of the solution, and the friction angle decreases with the increase of pH. Furthermore, the chemical erosion mechanism on the strength of granite was analyzed. Results obtained from laboratory tests could provide experimental data for the constitutive modeling of granite with chemical corrosion.