结合金坛地下盐穴储气库工程,以腔体围岩实际受力状态为研究依据,进行了盐岩卸围压力学特性试验,得到了盐岩卸围压过程的应力-应变关系、变形特征及其规律。试验结果表明,在卸围压初始阶段,试样的轴向和径向应变增加相对缓慢,且应变值和围压基本呈线性,随着围压继续降低,轴向与径向应变值急剧增加;卸载曲线与加载曲线相比,在最大主应力σ1相等的条件下,当卸载围压达到与常规三轴压缩围压相对应值时,对应的轴向和径向应变值较三轴压缩时应变值要大,表明卸荷试验能引起试样更大的变形,卸荷产生的扩容量比加载时扩容量更大,更容易导致试样变形破坏;盐岩卸围压表现为塑性变形特征,与其他硬岩卸围压属脆性破坏有较大区别。研究结果对盐穴储气库工程的稳定性评价和注采气过程具有一定的指导意义和参考价值。 Combined with the underground salt cavern gas storage project in Jintan, based on the actual stress state of the surrounding rock cavity, the stress-strain relationship of salt rock unloading confining pressure was obtained and the deformation Features and their laws. The experimental results show that in the initial stage of unloading confining pressure, the axial and radial strain increase relatively slowly, and the strain and confining pressure are basically linear. As confining pressure continues to decrease, the axial and radial strain values ​​increase sharply ; Unloading curve compared with the loading curve, under the conditions of equal maximum principal stress σ1, when the unloading confining pressure reaches the corresponding value with the conventional triaxial compression confining pressure, the corresponding axial and radial strain values ​​are triaxial compression The larger the strain value, indicating that the unloading test can cause greater deformation of the sample, unloading generated capacity expansion than the larger capacity when loaded, more likely to cause deformation and failure of the sample; salt rock unloading confining pressure showed plastic deformation characteristics , With other hard rock unloading pressure brittle failure have a greater difference. The results of the study have certain guiding significance and reference value for the stability evaluation of salt cavern gas storage project and the process of gas injection.