An empirical stochastic model for the geometry of two-dimensional crack growth in soil (with Discussion)

A model is presented for the fragmentation of drying soil, based on the geo metry of two-dimensional crack growth. The model restricts itself to the fo rmation of two-dimensional cracks. The pertinent parameters used to generat e cracking patterns include those used to characterise crack growth develop ment as a random walk, fragmentation of peds above a certain size threshold and attraction of cracks within defined distances. A sensitivity analysis is carried out to examine the effect of varying these parameters on final c racking patterns. The variation of curvature and threshold to aggregate spl itting are shown to have significant effects. Simulations based on this mod el are illustrated, and compared with cracks in real soil. (C) 2000 Elsevie r Science B.V. All rights reserved.