NUMERICAL INVESTAGATION OF THE MECHANISMS OF DESICCATION CRACKING IN FINE-GRAINED SOILS

Numerical simulations for desiccation shrinking and cracking in fine-grained soil, based on Distinct Lattice Spring Model by using a new developed micro mechanism, are performed. Negative pore water pressure and air entry value during drying are accountted for through a new introduced suction force constitutive law which describes the mechanical process of desiccation. Drying cracking of heterogeneous soil can be expressed by failure of the suction force at different time and different position where pore draining to dry is happening. The parameters obtained from free drying simulation are used to model the process of constrained drying. Comparisons are made between the simulation results and experimental data highlighting the capability of the model. A good agreement between simulation and exprimental presentation has been reached. In addition, the influences of random ratio and particle size are discussed in this paper as well.