Numerical Modeling of Desiccation Cracking Using the Cohesive Crack Method

Abstract

With the advent of climate change, it is thought that desiccation cracking of soil will lead to increases in damage to buried infrastructure. Desiccation cracking is a complex phenomenon that historically has been very difficult to model either numerically or analytically. Therefore, there is a need for knowledge on such models to be advanced rapidly. This paper discusses the introduction of cohesive cracks to model fracture attributable to desiccation. The cohesive crack method does not have the limitations of linear elastic fracture mechanics, namely, that an initial notch must be present and that the bulk material must behave in a linear elastic manner. This paper describes how the cohesive crack method has been successfully used to model laboratory desiccation tests of a clay soil. It is shown that, in addition to the tensile strength, the magnitude of fracture energy specified for the material has an impact on crack propagation. The cohesive crack method is proposed as a tool for the numerical modeling of desiccation cracking in many diverse fields.