Simulation of the cyclic loading and damage behavior of gypsum composites

Abstract

In this study, cellulose fiber reinforced gypsum based materials are investigated numerically and experimentally. This composite material is applied e.g., to sheath and brace timber frame wall elements. It shows a macroscopic response with pronounced strain softening. Due to its capability to dissipate high energy in cyclic loading and its pronounced damage tolerance, the specific material exhibits a high potential in seismically loaded structures. The finite element simulations of the homogenized fracture behavior and the strain localization are performed on the basis of the Plastic-Damage model proposed by Lubliner et al. [1] and Lee and Fenves [2] which have been applied mostly to quasi-brittle materials such as concrete, mortar or ceramics. The ABAQUS user subroutine of Rahman et al. [1] enables the simulation of these composites. A newly developed modification of this subroutine allows now to assign the subroutine to the structural level such as the softening zone and components subjected to tension threshold and tensioncompression loading. The input data are gained from quasi-static cyclic uniaxial tensile and compression experiments by applying parameter identification.