【摘要】 为准确预测建腔过程中泥岩夹层垮塌步距，保障盐穴储气库的稳定性，深入分析了泥岩夹层结构特征与力学特性，并建立夹层破断预测模型。通过对三水区盐矿布心组三段中亚段的泥岩夹层样品进行宏观分析与室内点载荷试验，发现：（1）泥岩夹层自上而下结构差异显著，上部结构致密，底部发育多角度裂隙（部分被盐岩充填），（2）据此将夹层划分为上部高强度泥岩与下部低强度泥岩，点载荷试验证实高强度泥岩的单轴抗压强度约为低强度泥岩的5.5倍；（3）在卤水浸泡下，高强度泥岩浸水初期（14 d内）软化效应显著，而浸泡后期强度趋于稳定，后期强度由夹层固有特性（高强度泥岩占比、夹层厚度）主导。基于上述特性，分析了泥岩夹层渐进破断机制，将其渐进破断过程划分为低强度泥岩破断、高强度泥岩破断及运营期破断三阶段。最终，建立综合考虑浸泡时间与夹层特性的断距预测公式。研究表明：（1）高强度泥岩占比大于临界值（约0.2）时，夹层易发生屈曲破断；（2）高强度泥岩占比较低时，则易出现非屈曲破坏。研究成果为盐穴储气库建腔过程中夹层垮塌预测与控制提供了理论依据。更多还原

【Abstract】 To accurately predict the collapse step distance of mudstone interlayers during cavern leaching and ensure the stability of salt cavern gas storage facilities, this study conducts an in-depth analysis of the structural characteristics and mechanical properties of mudstone interlayers, establishing a predictive model for interlayer fracture. Macroscopic analysis and point load tests on mudstone interlayer samples from Submember 3b of Member 3 of the Buxin Formation in the Sanshui District salt mine revealed the following:(1) the structural characteristics of the mudstone interlayer vary significantly from top to bottom, with the lower section developing multi-angle fractures(partially filled with salt rock), while the upper part remains dense;(2) consequently, the interlayer is categorized into an upper high-strength mudstone and a lower low-strength mudstone, with point load tests confirming that the uniaxial compressive strength of the high-strength mudstone is approximately 5.5 times that of the low-strength mudstone;(3) under brine soaking, the high-strength mudstone exhibits significant softening effects within the initial 14 days, after which its strength tends to stabilize; the long-term strength is primarily influenced by intrinsic interlayer characteristics, such as the proportion of high-strength mudstone and interlayer thickness. Based on these properties, the progressive fracture mechanism of the mudstone interlayer is revealed, which can be divided into three stages: low-strength mudstone fracture, high-strength mudstone fracture, and operational-stage fracture. Ultimately, a fracture distance prediction formula is established that comprehensively considers soaking time and interlayer characteristics(high-strength mudstone proportion and thickness). The study clarifies that:(1) buckling failure occurs in the interlayer when the high-strength mudstone proportion exceeds a critical value(approximately 0.2);(2) when the high-strength mudstone proportion is relatively low, non-buckling failure is more likely to occur. These research findings provide a theoretical basis for predicting and controlling interlayer collapse during the leaching of salt cavern gas storage facilities.更多还原