化学溶液及其水压作用下单裂纹灰岩破裂的细观试验

采用岩石破裂全过程的细观力学试验系统进行了化学溶液及其水压力作用下单裂纹灰岩压缩破裂试验。通过电镜扫描、X衍射、水质分析等分析方法，对岩石微观形貌、矿物成分等进行研究。采用数字显微系统，对其压缩破裂过程进行实时观测和记录，得到了岩石破裂过程的细观图像；探讨了蒸馏水、不同pH值的0.1 mol/L Na2SO4溶液及其水压力作用对单裂纹灰岩变形和强度特性的影响。研究表明，受化学侵蚀后岩石的结构及成分均发生了不同程度的变化，导致其非均质性增加，而强度、弹性模量等降低，其力学性质劣化的程度与岩石中矿物成分的变化程度相关；孔隙水压的作用改变了岩石内部裂隙面和颗粒间的受力状态，加速了岩石裂纹的扩展，降低了岩石强度，水化学溶液及其水压作用使得岩石的破裂形式变得更为复杂。

Meso-mechanical experimental study of meso-fraeturing process of limestone under coupled chemical corrosion and water pressure

An experiment of pre-existing flaw limestone fracturing process is conduced under uniaxial compression in order to investigate the behavior of rock fracturing under chemical corrosion and water pressure with a new meso-mechanical testing system. Analysis the varieties of limestone’s micro-structure and composition under chemical corrosion by SEM, X-ray diffraction, water quality analysis etc.. The meso-fracturing process of rock is real-time observed and recorded using the microscope. The mechanical behavior of specimens under chemical corrosion and water pressure are studied. The researches indicate that: under chemical corrosion, the micro-structure and mineral composition have changed differently, which increase the nonhomogeneity, and degrade the strength and modulus of elasticity. The degradation of mechanical property is related to the variety of mineral amount. Water pressure changes the loading state of crack and mineral grains, which increase the velocity of crack propagation, and reduce rock strength. So the fracturing behavior under chemical corrosion and water pressure becomes more complicate.