Soft interlayers are distiuctive geological units that serve as semi-permeable layers that regulate water flow and chemical transport in the subsurface. However, their hydrogeolocial characteristics are still poorly understood due to its unique sedimentary features. Duo to the low-permeability of Permian Maokou soft interlayers, water contents remain invariable and cause continuous weakening effect to its shear strength. Series of ring-shear creep tests are conducted to study the effect of water contents on ring-shear rheological properties. According to the experimental results, the instantaneous shear strain modulus is closely affected by water content, normal stress, and duration of test. Besides, the long-term shear strength and residual shear strength are close to each other when the normal stress is relatively small. But the strength reduction factor from the residual shear strength to the long-term shear strength should be considered under high normal stresses. Furthermore, the long-term cohesion and friction angle are obtained by fitting the long-term shear strength values under different normal stresses. An exponential function relation exists between the two long-term shear strength parameters and water contents. Finally, based on the analysis of the SEM (scanning electron microscope) results, it can be concluded that the effect of water content on rheology properties is mainly caused by lubrication, expansion of particles of samples in water. Micro-holes and cracks on failure surfaces also exhibit ductile failure characteristics.

软夹层是显着的地质单元，作为半渗透层，调节地下的水流和化学物质传输。然而，由于其独特的沉积特征，它们的水文地质特征仍然知之甚少。. 由于二叠系茅口软夹层渗透率低，含水量保持不变，对其抗剪强度产生持续减弱作用。进行了一系列环剪切蠕变试验，以研究含水量对环剪切流变特性的影响。根据实验结果，瞬时剪切应变模量受含水量、法向应力和试验持续时间的影响很大。此外，当正应力较小时，长期抗剪强度和残余抗剪强度接近。但在高正应力下应考虑从残余剪切强度到长期剪切强度的强度折减系数。此外，通过拟合不同法向应力下的长期剪切强度值，得到长期内聚力和摩擦角。两个长期剪切强度参数和含水量之间存在指数函数关系。最后，基于对SEM（扫描电子显微镜）结果的分析，可以得出结论，水分含量对流变性能的影响主要是由润滑，样品颗粒在水中的膨胀。破坏面上的微孔和裂纹也表现出延性破坏特征。