ABSTRACT
Many rubber-like materials and soft tissues exhibit a significant stiffening or hardening in their stress-strain curves at large strains. This chapter provides a brief review of some hyperelastic phenomenological constitutive models that have been proposed to model the strain stiffening effect and summarizes the advances in the solution of boundary-value problems that illustrate the utility of such models. The response of materials in some basic homogeneous deformations has been considered by Horgan & Saccomandi and by Horgan & Schwartz. In the authorative survey article on basic rubber elasticity, Gent has outlined the need for a satisfactory general treatment of networks under large deformations when the chains approach their fully stretched state. It has been demonstrated that the Gent model is amenable to explicit analytic solution for some basic problems of rubber elasticity involving nonhomogeneous deformations. The chapter also outlines generalizations of the Gent model to include thermoelasticity and material compressibility.
