Soft sedimentary rocks undergo deterioration due to weathering induced by dry–wet cycles in a process known as slaking. To investigate the effect of the initial water content and shear stress on the immersion-induced creep deformation and strength characteristics of gravelly mudstone (slaking index = 1 and 2), creep tests were conducted using a modified direct-shear-test apparatus under different creep-stress ratios. Crushed mudstone with different degrees of compaction and initial water content was subjected to immersion under the creep-shear-stress conditions. After the creep shear and vertical displacements stabilized, a monotonic shear loading was applied. During creep immersion, the increment in the creep-shear displacement increases as the creep-stress ratio increases and the initial water content and/or degree of compaction decrease. Retaining a high initial water content in crushed mudstone is recommended to maintain its shear-stress stability. Under the same density, the peak shear strength decreased with an increase in the increment of the creep-shear displacement during creep immersion. The results indicate that the occurrence of immersion-induced creep deformation in addition to slaking can result in the deterioration of slope stability.

由于干湿循环引起的风化作用，软沉积岩会发生退化，这一过程被称为熟化过程。为了研究初始含水量和剪切应力对碎石泥岩（熟化指数 = 1 和 2）浸入蠕变变形和强度特性的影响，在不同蠕变条件下使用改进的直接剪切试验装置进行蠕变试验。 - 压力比率。将不同压实度和初始含水量的碎泥岩在蠕变-剪切-应力条件下进行浸泡。在蠕变剪切和垂直位移稳定后，施加单调剪切载荷。在蠕变浸泡期间，蠕变剪切位移的增量随着蠕变应力比的增加和初始含水量和/或压实度的降低而增加。建议在碎泥岩中保持较高的初始含水量，以保持其剪切应力稳定性。在相同密度下，峰值剪切强度随着蠕变浸泡过程中蠕变剪切位移增量的增加而降低。研究结果表明，除了熟化外，浸没引起的蠕变变形会导致边坡稳定性的恶化。