The effects of wetting-drying (W-D) cycles on the desiccation-induced cracking of a fat clay (CH) as well as the role of soil suction in the evolution of soil strength, were investigated. Cylindrical block soil samples (50 mm in diameter and 100 mm in height) compacted to a dry density of 1.3 Mg/m³, were subjected to 3 stages of drying at a temperature of 22 ± 2 °C, the first of which had an initial water content of 25%. Three parallel samples were retrieved and tested for unconfined compressive strength (UCS) and surface fracture characteristics at moisture content levels ranging from 13% to 25%. Analyses of images of crack patterns obtained using stereological software, indicate that the pattern of increases in UCS with decreasing moisture content induced by drying, is strongly affected by the intensity of cracks on the samples. Desiccation cracking only occurred in the 2nd and 3rd stages of soil drying. During the first stage of drying, the stress-strain curve of the soil exhibited increase in slope with decreasing water content. This implies the domination of suction at the initial stages. The number of crack segments observed on samples, increases with W-D cycles, thus decreasing soil brittleness. However, increase in W-D cycles does not significantly affect the soil water retention characteristics. These findings illustrate the significant role played by soil suction in strengthening soils against the degradation effects of cracks during the early stages of drying. As drying proceeds, the proliferation of cracks eventually reduces soil strength as soil suction is overcome. Therefore, in developing structures on clayey soils that will be subjected to seasonal changes in moisture content, assessments of the balance of the effects of suction and soil desiccation cracking should be made.

研究了干湿循环（WD）对干燥引起的脂肪黏土（CH）开裂的影响，以及土壤吸力在土壤强度演变中的作用。圆柱状土壤样品（直径50毫米，高度100毫米）压实至干密度为1.3 Mg / m ³进行3阶段的干燥，温度为22±2℃，第一阶段的初始含水量为25％。取回了三个平行样品，并测试了水分含量在13％至25％范围内的无侧限抗压强度（UCS）和表面断裂特性。使用立体软件获得的裂纹图案图像的分析表明，UCS随干燥引起的水分含量降低而增加的模式，受到样品上裂纹强度的强烈影响。干燥开裂仅发生在土壤干燥的第二和第三阶段。在干燥的第一阶段，土壤的应力-应变曲线显示出随着水分含量的降低而增加的斜率。这意味着在初始阶段吸力占主导地位。随WD循环的增加，样品上观察到的裂纹片段数量增加，从而降低了土壤脆性。但是，WD循环的增加不会显着影响土壤保水特性。这些发现表明，在干燥的早期阶段，土壤吸力在增强土壤抵抗裂缝的降解作用方面发挥了重要作用。随着干燥的进行，裂缝的扩散最终会克服土壤吸力而降低土壤强度。因此，在粘土质土壤上开发的结构中，水分含量会随季节变化而变化，应评估吸力和土壤干燥开裂效果的平衡。WD循环的增加不会显着影响土壤保水特性。这些发现表明，在干燥的早期阶段，土壤吸力在增强土壤抵抗裂缝的降解作用方面发挥了重要作用。随着干燥的进行，裂缝的扩散最终会克服土壤吸力而降低土壤强度。因此，在粘土质土壤上开发的结构中，随着水分含量的季节性变化，应评估吸力和土壤干燥开裂效果的平衡。WD循环的增加不会显着影响土壤保水特性。这些发现表明，在干燥的早期阶段，土壤吸力在增强土壤抵抗裂缝的降解作用方面发挥了重要作用。随着干燥的进行，裂缝的扩散最终会克服土壤吸力而降低土壤强度。因此，在粘土质土壤上开发的结构中，随着水分含量的季节性变化，应评估吸力和土壤干燥开裂效果的平衡。由于克服了土壤吸力，裂缝的扩散最终降低了土壤强度。因此，在粘土质土壤上开发的结构中，随着水分含量的季节性变化，应评估吸力和土壤干燥开裂效果的平衡。由于克服了土壤吸力，裂缝的扩散最终降低了土壤强度。因此，在粘土质土壤上开发的结构中，随着水分含量的季节性变化，应评估吸力和土壤干燥开裂效果的平衡。