NONLINEAR MICRO-MECHANICAL MODEL FOR PLAIN WOVEN FABRIC

The warp yarns and weft yarns of plain woven fabric which,being the principalaxes of material of fabric,are orthogonal in the original configuration,but are obliquely crossedin the deformed configuration in general.The orthotropic constitutive model is unsuitable forfabric.In the oblique principal axes system the relations between loaded stress vectors and stresstensor are investigated,the stress fields of micro-weaving structures of fabric due to pure shearare carefully studied and,finally,a nonlinear micro-mechanical model for plain woven fabric isproposed.This model can accurately describe the nonlinear mechanical behavior of fabric observedm experimeuts.Under the assumption of small deformation and linearity of mechanical propertiesof fabric the model will degenerate into the existing linear model.