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Fig. 1. Scheme explaining Bronswijk's (1988)(1989, 1990, 1991a, 1991b) model of soil layer shrinkage and cracking. (a) Shrinkage of elementary soil cube at initial layer thickness z and volume V = z3 as a result of subsidence 
z and lateral reduction of initial cube sides to x and y; the volume supplementing the reduced cube [i.e., parallelepiped: x x y x (z – z)] in lateral directions up to volume z x z x (z – z) is interpreted as a crack volume per one initial cube. (b) The initial soil layer composed from unconnected elementary cubes and the layer after shrinkage composed from corresponding parallelepipeds and crack volumes; arrows symbolize the continuation of the three shown cubes to the unlimited layer.
