Wheat field and Dominoes

Once perturbed, an alignment of identical slender elements can either oscillate around an equilibrium position and propagate waves (wheat field limit) or destabilise and propagate a shock (dominoes limit). In the wheat field limit, we show that two kinds of waves can be observed depending on the intensity of the forcing wind. In the dominoes limit we study the shape of the shock and show that its velocity only depends on the height of a domino and on the spacing between the different elements.