三轴应力作用下岩盐溶解速率影响因素分析

利用自行研制的三轴岩盐溶解试验机，实现在三轴应力条件下岩盐试样溶解试验。进行三轴应力条件下溶液浓度、温度、流量以及偏应力4个因素相互耦合状态的岩盐溶解速率正交试验，研究各个因素对岩盐溶解速率的影响规律。对任意两个影响因素分别进行二元线性回归，根据其标准回归系数对岩盐溶解速率相对重要性比值构建判断矩阵，运用层次分析法计算各个影响因素的权值。研究结果表明，岩盐溶解速率随着浓度增大迅速降低，随着温度升高而增大，随着流量增大缓慢增加，但变化并不明显；随着偏应力增大先减小，后缓慢增大。极差分析和权值计算结果表明，岩盐溶解速率影响因素主次关系依次为浓度、温度、流量和偏应力。4个因素对岩盐溶解速率影响权值大小依次为0.570、0.384、0.048、0.005，其中浓度和温度两个影响因素权重占到95%。

Analysis of factors influencing rock salt dissolution rate under triaxial stress effect

Rock salt sample dissolution tests under on the condition of triaxial stress with self-designed triaxial testing machine, rock salt dissolution rate orthogonal experiment under the mutual coupling of concentration, temperature, flow and deviatoric stress under the condition of triaxial stress, are carried out. Various factors influencing rock salt dissolution rate are studied. Any two factors are the binary linear regression, the relative importance ratio according to the standardized regression coefficients for rock salt dissolution rate to build judgment matrix; analytic hierarchy process is used to calculate weights of various factors. The results show that: Rock salt dissolution rate decreased rapidly with the concentration increasing. Dissolution rate increases with the temperature rising. Dissolution rate increases slowly with the flow increasing and did not change significantly. Dissolution rate decreases first and then slowly increases with increasing deviatoric stress. Range analysis and weights calculation show that primary and secondary factors affecting the rock salt dissolution rate are concentration, temperature, flow and the deviatoric stress. The weights of concentration, temperature, flow and the equivalent stress affecting the dissolution rate are 0.570, 0.384, 0.048, 0.005 respectively; the weights of the two factors, concentration and temperature, account for 95%.