Modeling soil desiccation cracking by analytical and numerical approaches

Amade Pouya (1) , Thi Dong Vo (2) , Sahar Hemmati (1) , Anh Minh A.M. Tang (3)

1 navier umr 8205 - Laboratoire Navier
2 IFSTTAR - Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux
3 cermes - Géotechnique

An energy approach is proposed as a complement to the stress approach commonly considered for investigating soil desiccation cracking. The elastic strain energies before and after crack initiation are estimated by both numerical and analytical solutions. The energy released by cracking is then compared with the fracture energy to discuss crack initiation conditions. This leads to combined energy and stress conditions for crack initiation following Leguillon's theory. An approximate analytical solution is derived from a variational formulation of the porous elastic body equations. A cohesive zone model and finite element code are used to simulate crack propagation in an unsaturated porous body. This analysis shows that the energy criterion is reached before the stress criterion, and this can explain unstable crack propagation at the beginning. The approximate analytical solution allows predicting correctly the crack depth and opening in its initiation stage.

Mots clés: energy criterion; cohesive zone model.; desiccation cracks; crack initiation; crack propagation

Domaines: Géotechnique

Amade Pouya, Thi Dong Vo, Sahar Hemmati, Anh Minh A.M. Tang. Modeling soil desiccation cracking by analytical and numerical approaches. International Journal for Numerical and Analytical Methods in Geomechanics, 2019, 43 (3), pp.738-763. ⟨10.1002/nag.2887⟩. ⟨hal-02130377⟩