Modelling desiccation cracking in a homogenous soil clay layer

Modelling desiccation cracking in a homogenous soil clay layer: Comparison between different hypotheses on constitutive behaviour

Jommi, C. (TU Delft Geo-engineering)
Valimberti, N. (Politecnico di Milano)
Tollenaar, Roderick N.
Della Vecchia, Gabriele (Politecnico di Milano)
van Paassen, L.A. (TU Delft Geo-engineering)

2016-09-12

Desiccation cracks are usually thought to start from the surface of an evaporating soil layer, and the available simplified models for crack initiation and propagation are based on this hypothesis. On the contrary, experimental results on a Dutch river clay showed that cracks in an evaporating soil layer may start and propagate below the surface, confirming earlier findings by other researchers. A simple one-dimensional model was set up to analyse the consequences of different hypotheses about the material behaviour on the crack onset in a homogenous soil layer undergoing surface drying. The results of the model show that dependence of the material behaviour on the rate of water content change is a necessary requirement for cracks to initiate below the surface. The conclusion suggests that, to properly understand cracking in an evaporating soil layer, an intrinsic time scale for the mechanical response must be accounted for, among all the other factors which were previously highlighted by other researchers. The key factor to predict crack onset below the surface is the dependence of the drying branch of the water retention curve of the compressible soil on the rate of drying, which would be justified by a rate dependent fabric evolution.

http://resolver.tudelft.nl/uuid:93991ba2-03bd-42cd-981f-58710d6369ae

https://doi.org/10.1051/e3sconf/20160908006

3rd European Conference on Unsaturated Soils – “E-UNSAT 2016” : Paris, France, September 14-16, 2016., 9

E3S Web of Conferences 9, 2267-1242, 9 (09006)

Institutional Repository

conference paper

© 2016 C. Jommi, N. Valimberti, Roderick N. Tollenaar, Gabriele Della Vecchia, L.A. van Paassen