Modelling Fabric-Reinforced Membranes with the Discrete Element Method

A model for fabrics and fabric reinforced membranes is presented, in which the Discrete ElementMethod (DEM) is applied to a microstructure representation of fabrics on the yarn level. The unit cell is described by discrete mass points and rheological elements. Their assembly represents the relevant deformation mechanisms like crimp interchange, trellising or locking. Additional interaction mechanisms are implemented that account for a coating or embedding of the fabric. In the framework of a Discrete Element description the model is intrinsically dynamic since the equations of motion are solved numerically for every mass point using a predictor-corrector scheme, i.e. an explicit finite difference method. With this model the influences of different microscopic material features on the macroscopic system response are studied, preserving directly the information of the local microstructure deformation. All micromechanisms are implemented in a modular manner in order to make the model adaptable to materials that range from pure fabrics to fabric reinforced membranes. Numerical results are presented that demonstrate the plausibility of our approach.