Reduced models of swelling-induced bending of gel bars

The purpose of the paper is to present a class of reduced models borrowed from structural mechanics aimed at specifically describing swelling-induced bending deformations in a gel bar. A distinct bending pattern to be confirmed by an appropriate experimental setup is evidenced through the analysis of a plane stress–diffusion model. Moreover, a further reduced 1D stress–diffusion model driven by an integro-differential equation is derived. In particular, it is shown that there exists a range of the material parameters where the standard 1D diffusion equation holds.