Visco-Plastic Constitutive Equation of ETFE Film - Examination on the Stress- Strain relationships of Uniaxial and Biaxial Tensile Deformation

This paper presents an examination of the validity of a viscoplastic constitutive equation combining kinematic hardening creep theory and nonlinear kinematic hardening theory in order to describe the viscoplastic behavior of ETFE film. A viscoplastic constitutive equation compared with experiment al results for stress-strain relationship of the film, as it pertains to strain rate dependence and the plastic region. And then, the stress-strain relationship in annealed film was also investigated to determine post-yield structural behavior.