A PLANE-STRESS SOFTENING PLASTICITY MODEL FOR ORTHOTROPIC MATERIALS

A plane stress model has been developed for quasi-brittle orthotropic materials. The theory of plasticity, which is adopted to describe the inelastic behaviour, utilizes modern algorithmic concepts, including a n implicit Euler backward return mapping scheme, a local Newton-Raphso n method and a consistent tangential stiffness matrix. The model is ca pable of predicting independent responses along the material axes. It features a tensile fracture energy and a compressive fracture energy, which are different for each material axis. A comparison between calcu lated and experimental results in masonry shear walls shows that a suc cessful implementation has been achieved. (C) 1997 John Wiley & Sons, Ltd.