Compression induced intercellular shaping for some geometric cellular lattices

The wall perimeter fraction, which contact neighboring cells, was named com pression ratio (alpha). A zero compression ratio indicates maximum intercel lular (air) volume (nu (G), nu/nu) and neglectable contact among cells, whi le alpha =1 indicates complete adherence between neighboring cells and no V G in the lattice. The maximum intercellular air volume (,beta, nu/nu), when alpha =0, was 0.593 for triangular, 0.2146 fbr square and 0,0931 for hexag onal lattices. The equation alpha =1- (nu (G)/beta)(1/2) was derived to rel ate alpha, beta and nu (G) in the studied lattices. The relation (Ps=p/alph a) between cell turgor (PS) and the tissue aggregating pressure (p), define d as the compression to keep in place a layer of cells, was demonstrated us ing the compression ratio concept. Intercellular deformations of Ipomea bat atas L. roots obtained with pressure chamber were used to test alpha, nu (G ), p and Ps as a function of compression. Volumetric and transversal elasti c extensibilities and the lamella media tearing forces were obtained and a constancy was considered as a criteria of cellular shape stability.