Simulation of the mechanical behavior and damage in components made of strain softening cellulose fiber reinforced gypsum materials

Cellulose fiber reinforced gypsum based materials are gaining increasing importance in the building industry. The non-combustible panel material is produced in thicknesses of 10–40 mm and with a fiber content of about 20 vol.%. The fiber orientation in the composite is predominantly random planar. A major application for the panels is sheathing and bracing of timber frame wall elements. The material exhibits a macroscopic response that resembles that of a ductile material with pronounced strain softening. These material characteristics, which deliver high energy dissipation especially during reversed cyclic loading, are advantageous for seismically loaded structures. In this paper the homogenized fracture behavior for this material is described for the first time for static and quasi-static cyclic loading using a Plastic-Damage model proposed by [J. Lubliner, J. Oliver, S. Oller, E. Oñate, Int. J. Solids and Structures 25, 3 (1989), 229–326, J. Lee, G. L. Fenves, J. Eng. Mech. 124, 8 (1998), 892–900]. This model is primarily used to simulate quasi-brittle materials such as concrete, rock, mortar and ceramics. The model input parameters such as tensile strength and fracture energy are obtained from uniaxial test results. The numerical simulations have been performed with ABAQUS. The different features and parameters of the applied Plastic-Damage model are discussed with respect to their capability to describe the behavior of cellulose fiber reinforced gypsum.