Mechanics of mutable hierarchical composite cellular materials

摘要

Cellular structures having the internal volumes of the cells filled with fluids, fibres or other bulk materials are very common in nature. A remarkable example of composite solution is the hygroscopic keel tissue of the ice plant Delosperma nakurense. This tissue, specialized in promoting the mechanism for seed dispersal, reveals a cellular structure composed by elongated cells filled with a cellulosic swelling material. Upon hydrating, the filler adsorbs large amounts of water leading to a change in the cells' shape and effective stiffness.