Fig. 3.

Configurations selected by a homogeneous substrate attached to a Winkler foundation. In (a) we show the first four neutral curves, illustrating the cellular compression, $\xi =-12T\left(1-{\nu }^2\right)$, required to buckle the substrate as a function of foundation stiffness, η. In (b)–(f) we illustrate the eigenmode corresponding to the lowest value of T for various η, as indicated in (a). Dark blue (resp. red) colouring represents unit downward (resp. upward) buckling. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)