Formation of drying crack patterns in soils: a deterministic approach

Abstract

Soils, as well as most of deformable multiphase porous materials, are likely to suffer from desiccation cracking, leading to the formation of regular crack patterns affecting their permeability. The ensuing crack spacing has often been related to a concept sometimes called ''sequential infilling'': it is assumed that desiccation cracks are formed by successive generations. However, such a concept does not consider the pattern of a simultaneous crack formation at a given moment. Using our desiccation cracking test results and their numerical simulation, we propose a consistent explanation for the formation of desiccation crack patterns in soils. We show that the ''sequential infilling'' concept is suitable only when the position of the crack(s) clearly stems from the stress field. To derive an estimate of the desiccation crack spacing, the overall energy of the system needs to be considered. Statistical variability should be superimposed on the mean deterministic conditions discussed here.

Modeling soil desiccation cracking by analytical and numerical approaches

“…First, primary cracks are developed dividing the soil surface into cells, and then subsequent drying tends to subdivide these cells in the form of secondary and tertiary crack families. In addition, the crack patterns observed experimentally by Peron et al showed that the crack network formation can result from the combination of two processes, “sequential infilling” and “simultaneous growing,” since the cracks tend to appear either successively or simultaneously. The sequential infilling occurs to create different families of cracks, but the simultaneous growing can occur within each family.…”

“…The sequential infilling occurs to create different families of cracks, but the simultaneous growing can occur within each family. The “sequential infilling” concept for desiccation cracking should be invoked only when cells of an intact material with a reduced, well‐defined size can be individualized . The initiation of crack is influenced by the two major factors: stress distribution and presence of flaws .…”

“…The "sequential infilling" concept for desiccation cracking should be invoked only when cells of an intact material with a reduced, well-defined size can be individualized. 34 The initiation of crack is influenced by the two major factors: stress distribution and presence of flaws. 28 Therefore, the simultaneous propagation can occur in the long specimens with few flaws.…”

“…Moreover, using desiccation cracking test results and numerical simulation, Peron et al proposed a consistent explanation for the formation of desiccation crack patterns in soils. The authors gave an estimation of desiccation crack spacing by calculating the overall energy of the system.…”

Strain Localization and Shear Band Propagation in Ductile Materials

“…2 The proposed explanation for the crack patterns shown in Figure 2 relies on the fact that the fracture network has formed during the plastic evolution of a ductile homogeneously deformed material. Other explanations may be related to bonding of an external layer to a rigid substrate (Peron et al, 2013), or to surface instability (Destrade and Merodio, 2011;Boulogne et al, 2015), or to instabilities occurring during shear (Destrade et al, 2008;Ciarletta et al, 2013). initiated with pioneering works by Hill (1962), Nadai (1950), Mandel (1962), Prager (1954), Rice (1977), Thomas (1961), and developed -from theoretical point of view -into two principal directions, namely, the dissection of the specific constitutive features responsible for strain localization in different materials (for instance, as related to the microstructure, Danas and Ponte Castaneda, 2012;Bacigalupo and Gambarotta, 2013;Tvergaard, 2014) and the struggle for the overcoming of difficulties connected with numerical approaches [reviews have been given by Needleman and Tvergaard (1983) and Petryk (1997)].…”