A clay is prone to shrinkage and cracking under evaporation, which can cause vast hazards in geotechnical and geo-environmental engineering. Knowledge of the coupled behavior of dynamic cracking and moisture-heat evolution is helpful for better understanding the mechanical performance of a clay under evaporation. An evaporation experiment was conducted on a clayey soil specimen in this study, accompanied by observation of shrinkage and cracking and monitoring of moisture-heat. In this way, the fully coupled behavior of shrinkage, cracking, and moisture-heat evolution of the clay under evaporation was investigated. The results show that the clay loses most of its water and achieves most of the shrinkage before the latter evaporation stage. Especially in the intermediate evaporation stage, the soil saturation has a quick reduction, the soil suction has a linear increase, and the soil temperature has a sharp rise. Because of this moisture-heat evolution, both the degree of the nonuniform shrinkage and the increased rate of the crack ratio and the crack depth reach the maximum values. Along with the crack developing downward and bringing new air-entry channels, the actual evaporation front also moves downward. The evaporation from the surface-exposed crack can significantly affect the moisture-heat evolution of the clay. The crack can develop further to the width and the depth owing to the nonuniform shrinkage existing at the different locations and the different depths of the clay. The nonuniform shrinkage may be attributed to the heterogeneity of the soil properties, the inhomogeneous evaporation environment, and the huge difference of moisture-heat characteristics of the clay.

粘土在蒸发下易于收缩和开裂，这可能在岩土工程和地球环境工程中造成巨大危害。了解动态开裂和湿热释放的耦合行为有助于更好地了解蒸发条件下粘土的机械性能。在这项研究中，在黏性土壤标本上进行了蒸发实验，同时观察了收缩和开裂并监测了湿热。通过这种方式，研究了蒸发条件下粘土的收缩，开裂和湿热演化的完全耦合行为。结果表明，粘土在随后的蒸发阶段之前损失了大部分水分，并实现了大部分收缩。特别是在中间蒸发阶段，土壤饱和度会迅速降低，土壤吸力呈线性增加，土壤温度急剧上升。由于这种湿热的发展，不均匀收缩的程度以及裂纹率和裂纹深度的增加率均达到最大值。随着裂缝向下发展并带来新的进气通道，实际的蒸发前沿也向下移动。从暴露在表面的裂缝中蒸发会显着影响粘土的湿热演化。由于存在于粘土的不同位置和不同深度处的不均匀收缩，裂纹可进一步扩展到宽度和深度。收缩不均匀可能归因于土壤性质的异质性，蒸发环境的不均匀性，