Indexed on: 24 Nov '13Published on: 24 Nov '13Published in: Journal of the Brazilian Society of Mechanical Sciences and Engineering
In this paper, we revisit two orthotropic material models proposed in previous works and develop their expressions to obtain their elastic parameters via calibration with experimental data. Our purpose is to make these models available to the nonlinear finite element analysis of structural membranes. We describe the membrane kinematics as a geometrically exact thin shell, whose in-plane orthotropic character is introduced solely at the constitutive equation. Accordingly, small bending, transverse shear and compressive stiffnesses are always present due to the shell assumptions. A least-squares minimization problem is formulated and resolved for the obtaining of the elastic parameters. Stress–strain curves of physical stretch tests are used to this end. The two resulting models were implemented into a nonlinear finite element code and numerical simulations of the stretch tests are conducted to assess the performance of the scheme.