卤水浸泡环境下盐岩剪切特性影响因素分析

为了解水溶造腔过程中盐岩在卤水浸泡环境中的剪切特性，设计了盐岩剪切特性影响因素的正交试验，研究了卤水浸泡时间、温度和加载速率对盐岩剪切特性的影响规律。试验结果表明，卤水浸泡会弱化盐岩的抗剪强度，卤水浸泡时间越长盐岩抗剪强度越低，但最终趋于稳定；卤水温度升高，加剧盐岩内部损伤，盐岩抗剪强度随之降低；经一定温度卤水浸泡后盐岩的抗剪强度随加载速率的增大而降低，且其延性特征也随浸泡时间、温度和加载速率的增大逐渐减弱。通过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盐岩抗剪强度的相对重要性比值构建判断矩阵，运用层次分析法计算出温度、加载速率和浸泡时间等影响因素的权值分别为0.397，0.340，0.263。极差分析和权值计算表明，盐岩剪切强度的影响因素主次关系依次为温度、加载速率和浸泡时间。

Analysis of influencing factors of salt rock’s shear characteristics in brine soak environment

In order to investigate the shear characteristics of salt rock in brine soak environment during the process of salt cavern building, an orthogonal experiment is designed to investigate the influences of brine soak time, temperature and loading rate on the shear properties of salt rock. The experimental results show that: brine soak weakens the shear strength of salt rock, and the longer the brine soak time is, the lower the shear strength of salt rock is, but the shear strength will be stabilized eventually; the increasing of brine temperature exacerbates internal damage of salt rock, which decreases shear strength; the shear strength of salt rock, soaked in a certain temperature brine, decreases with the increasing of loading rate. And the ductile characteristics of salt rock are gradually weakened with the increasing of soak time, temperature and loading rate. The binary linear regression is respectively conducted by any two factors, the relative importance ratio is used to build judgment matrix according to the standardized regression coefficients for salt rock’ shear strength, and weights of various factors are calculated by analytic hierarchy process. The weights of temperature, loading rate and soak time respectively are 0.397, 0.340, and 0.263. The results of range analysis and weights calculation show that the primary factor affecting the shear strength of rock salt is temperature, and the secondary factor is loading rate, followed by the soaking time.