Desiccation-induced cracking and curling in clay soils are common phenomena that significantly affect their mechanical and hydraulic properties. These processes result from the rearrangement of soil particles due to moisture loss, leading to volumetric shrinkage and crack formation. This paper provides a comprehensive review of the mechanisms and patterns of cracking and curling in clay soils during desiccation, with an emphasis on the role of capillary pressure and tensile strength in controlling these behaviors. The review integrates findings from field observations, laboratory experiments, established theories, and numerical modeling approaches. A systematic summary of experimental methodologies used to investigate these phenomena is presented, highlighting the importance of fracture mechanics in understanding the crack propagation process. The paper discusses the influence of plasticity characteristics of clay soils on desiccation cracking and identifies key areas for future research, including the need for further in-situ experiments and more advanced numerical studies.

The mapping of failure that uses acoustic emission (AE) is an advanced approach when tracking the location of cracks in rock materials under progressive stress. However, attenuation of the acoustic wave significantly affects the identification of the acoustic source. The isotropic attenuation model suggests a constant attenuation in all rock material directions, which provides unrealistic failure mapping for anisotropic rocks. This study investigated the impact of high attenuation on the mapping failure of a composite (sandstone–shale–sandstone), intact sandstone, and shale specimens that used AE under axile stress. The results proved that wave attenuation is the primary obstacle when obtaining a compatible failure map to the real specimen failure. Multiple setups of AE sensors were implemented to quantify the attenuation values for a wave that propagated across composite joints and shale bedding planes. The amplitude and energy attenuation (EA) values increased by 85% and 47%, respectively, when the bedding plane of the shale was from 0° to 90°, which reflected anisotropic behavior. The energy and amplitude reduction reached 99% and 39%, respectively, by propagating across a single joint. In addition, behind a double joint, no signal was received. However, the application of a load perpendicular to the joint interface improved the acoustical–wave characteristics. Therefore, when the rock material anisotropy was increased, there was lower accuracy when mapping specimen failure, because the attenuation varied at each angle between the source and sensor. In addition, the EA method suggested in this study presented hits location more precisely compared with the P-velocity (Vp) method. These findings could contribute to the development of an anisotropic attenuation model for field and laboratory application of AE.

Shear modulus (G) is one of the most important parameters in geotechnical design to ensure adequate margin of safety is maintained in the design of constructions such as buildings. There is a direct relationship between the shear modulus and shear wave velocity (Vs) which can get easily from Seismic methods. Some of Seismic methods have shortages which make electrical method much attractive for example, there is no interfere with external factors like noise in electrical technique. This paper, shows the relationship between electrical resistivity and Young’s modulus (E) using regression equation to get shear modulus. From the latter, shear wave velocity can easy to determine. Soil density and Poisson’s ratio was taken as an exact value depending on the profile of the soil to determine shear wave velocity and shear modulus respectively. This paper illustrates a good relationship between Young’s modulus and electrical resistivity. Correlation equation between shear wave velocity and N-value was predicted to represent Malaysia’s soil and the result was strongly close to previous soil equations of several countries.