三轴应力作用下岩盐溶蚀特性试验研究

通过大量的三轴应力作用下岩盐溶蚀特性试验，对岩盐溶蚀特性进行了研究，结果表明，对于岩盐溶解速率来说，三轴应力作用的影响不可忽略；采用宏观溶解速率（即溶蚀质量）与围压、塑性体应变和溶解时间之间的关系来定量描述三轴应力作用下岩盐溶解速率的变化，并在试验的基础上获得了宏观溶解速率与围压、塑性体应变和溶解时间之间的关系表达式；在相同的溶解时间、塑性体应变条件下，不同围压下岩盐试样溶蚀前后的形态差异较明显，应力影响质量变化较大，且随着围压的增加，试样溶蚀后形态的变化越小，应力影响质量越小；揭示了三轴应力作用下岩盐溶蚀特性变化机制，得出三轴应力作用下岩盐溶解速率变化与不同围压下表面裂纹的发育与扩展有着直接的联系。该研究成果为进一步研究岩盐应力-溶解耦合机制奠定了试验依据以及理论基础。

Experimental study of rock salt dissolving characteristics under triaxial stress

Through a lot of tests under triaxial stress,rock salt dissolving characteristics have been studied.The results show that the influence of triaxial stress on rock salt dissolving velocity can not be ignored;the relationships between macro dissolving velocity(can be equal to dissolved mass in tests) and confining pressure,plastic volumetric strain and dissolving time,can be used to quantitatively describe the variation of rock salt dissolving velocity under the effect of triaxial stress according to the test data;the numerical expressions between macro dissolving velocity and confining pressure,plastic volumetric strain and dissolving time,are obtained;at the same dissolving time and plastic volumetric strain condition,under the different confining pressures,the obvious difference between the shape of rock salt sample before and after dissolved exists;dissolved mass with stress effect changes greatly,and with increased confining pressure,dissolved mass with stress effect on the variation for the shape decreases;the obtained mechanism of rock salt dissolving characteristics under triaxial stress is that the direct relationship between rock salt dissolving velocity under triaxial stress and development of surface cracks under different confining pressures is obtained.The achieved results can provide a foundation for the further analyses of coupled stress-dissolving mechanism of rock salt.