This study addresses the crack evolution law and shear behavior of weak muddy intercalations (WMIs) during wetting-drying cycles. The original crack images of WMI were processed; adjustments were made to overcome the reflective differences of crack on the surface of the WMI samples caused by the uneven surface and impurities, effectively distinguishing the crack and non-crack areas in the images of the WMI sample surface. In addition, the total length, average width, area ratio, and number of cracks were extracted as the index represents the crack condition of the WMI sample surface. Shear testing on surface of the WMI sample was used to analyze the shear properties for different wetting-drying cycles, and the relationships between crack propagation and shear properties in the wetting-drying cycles were considered. The results show that the wetting-drying cycles elongate crack on the surface of the WMI sample. The average widths of the cracks also increase, and a large number of new tensile cracks are generated. As a result, the crack degree increases with the wetting-drying cycles. Crack propagation could also weaken the WMI structure as the development of the crack may reduce the tight contact points between WMI particles, leading to decreased cohesion in the WMI. As for the shear behavior of the WMI, the shear strength may decline with the wetting-drying cycles but tends to stabilize after a certain number of cycles.

这项研究解决了干湿循环过程中弱泥泞夹层（WMI）的裂纹演化规律和剪切行为。处理了WMI的原始裂缝图像；进行了调整，以克服由于表面不平整和杂质造成的WMI样品表面裂纹的反射差异，从而有效地区分WMI样品表面图像中的裂纹和非裂纹区域。另外，提取总长度，平均宽度，面积比和裂纹数，因为该指标代表WMI样品表面的裂纹状态。使用WMI样品表面的剪切测试来分析不同干湿循环的剪切性能，并考虑了干湿循环中裂纹扩展与剪切性能之间的关系。结果表明，干湿循环延长了WMI样品表面的裂纹。裂纹的平均宽度也增加，并且产生大量新的拉伸裂纹。结果，裂纹程度随着干湿循环而增加。裂纹扩展还会削弱WMI结构，因为裂纹的发展可能会降低WMI粒子之间的紧密接触点，从而导致WMI内聚力降低。至于WMI的剪切行为，剪切强度可能会随着干湿循环而下降，但在一定次数的循环后趋于稳定。裂纹扩展还可能削弱WMI结构，因为裂纹的发展可能会降低WMI粒子之间的紧密接触点，从而导致WMI内聚力降低。至于WMI的剪切行为，剪切强度可能会随着干湿循环而下降，但在一定次数的循环后趋于稳定。裂纹扩展还可能削弱WMI结构，因为裂纹的发展可能会降低WMI粒子之间的紧密接触点，从而导致WMI内聚力降低。至于WMI的剪切行为，剪切强度可能会随着干湿循环而下降，但在一定次数的循环后趋于稳定。