为了揭示水浸泥岩基底内排土场边坡失稳机理，采用室内试验探究了泥岩弱层抗剪强度参数随含水率的损伤演化规律，结合数值计算软件分析了含水率对内排土场边坡位移、滑移破坏特征及安全系数的响应特征。结果表明：随着泥岩弱层含水率的增加，黏聚力和内摩擦角呈非线性减小的二次函数分布规律；边坡最大水平位移、最大垂直位移和最大剪应变与含水率均呈正相关关系，边坡以水平运动为主，主要呈现沿排土场基底接触面的滑移破坏；边坡安全系数与含水率呈负相关关系，为保证边坡稳定，泥岩弱层含水率不超过30%。

In order to reveal the instability mechanism of waste dump slope in water soaked mudstone base, the damage evolution law of shear strength parameters of weak mudstone layer with water content is explored by indoor test. Combined with numerical calculation software, the response characteristics of water content to displacement, sliding failure characteristics and safety factor of waste dump slope are analyzed. The results show that with the increase of water content in weak mudstone layer, the distribution law of cohesion and internal friction angle decreases nonlinearly; the maximum horizontal displacement, maximum vertical displacement and maximum shear strain of the slope are positively correlated with the water content. The slope is dominated by horizontal movement, mainly showing sliding failure along the contact surface of the waste dump base; the safety factor of the slope is negatively correlated with the water content. In order to ensure the stability of the slope, it is recommended that the water content of the weak layer of mudstone should not exceed 30%.