Desiccation Cracking Behavior of a Clayey Soil with Different Compaction States

Desiccation cracks have an important effect on engineering mechanical properties of clayey soil. This paper investigated the soil desiccation cracking behavior response to various compaction states. We performed desiccation tests on soil specimens with different compaction water contents and dry densities in a constant temperature chamber. The evolution of typical crack parameters during drying, as well as the crack width distribution after drying, was monitored and quantitatively analysed using image processing methods. The findings reveal that the cracking water content where soil cracking occurs decreases with increasing compaction water content or initial dry density. An increase in either compaction water content or initial dry density is correlated with a decreasing trend in surface crack ratio. Meanwhile, average crack width and total crack length exhibit similar variations. The microstructure of soil compacted at various compaction states plays a critical role in its cracking behavior. It should be noted that soil specimens at high compaction water contents or high dry densities may still develop some cracks with wide widths, despite having low average crack widths and surface crack ratios. This strongly affects the permeability of the soil.