Numerical modelling of desiccation cracking in a restrained ring test

Abstract

Tensile cracking due to desiccation and fracture properties are of great importance in clay liners, earth dam engineering, waste contaminant systems, and mine tailings. This paper presents restrained shrinkage test results and analyses of consolidated desiccating soil, and compares results with numerical analyses using the computer program Universal Distinct Element Code (UDEC). The cohesive crack method was used as it is more appropriate than linear elastic fracture mechanics for soil cracking at high moisture contents with the likely presence of plasticity during fracture. The variation of the radial stresses on the inner ring with water content was used to model mode I cracking and gather fracture properties of the propagating crack. The model was validated on kaolin clay tested under restrained ring shrinkage and was compared with various test results and results from the literature. The test could be a valuable tool in determining fracture properties during desiccation.