Experimental Studies on Dissolution Properties of Rock Salt Under Triaxial Deviator Stress

Using self-developed testing machine of three-axis rock salt solubility, salt solubility test was done in partial triaxial stress conditions. Tests show that the dissolution characteristics of rock salt under triaxial stress have changed significantly, Rock salt dissolution rate decreases first and then increases with the intensifying of stress on condition that flow and dissolution time are steady, The quality of dissolved salt raises with the extension of time. After a qualitative analysis of test results showed that: In the elastic stage, the axial stress takes the compression effect on the sample. It allows to reduce the crack of rock salt samples and the crack through. At the same time confining pressure can inhibit the expansion of micro-crack specimens, so that slowly reduce the salt dissolution rate. When the sample into the plastic stage, with the development growth of rock salt specimen crack, dissolution rate increased constant, the conclusion which is shown as salt dissolution velocity that has a close relationship with the triaxial stress of the sample and the crack propagation,has been reached.