GWFMM model for bi-modulus orthotropic materials: Application to mechanical analysis of 4D-C/C composites

This paper proposes a new constitutive model named general weighted flexibility matrix (GWFMM) material model for the analysis of structures made of bi-modulus orthotropic material in complex three-dimensional stress state. The material properties of the GWFMM model are assigned according to the positive-negative signs and magnitudes of the principal material stresses. General analysis modules of the orthotropic materials with different moduli of elasticity in tension and compression are developed. Comparing with Bert's model for laminated materials, GWFMM model can obtain more accurate mechanical response of structures in complex three-dimensional stress states.