This study investigates the progressive failure analysis of a tapered thick composite plate. The governing differential equation of motion of the various tapered configurations of a thickness tapered reinforced composite plate are... more
This study investigates the progressive failure analysis of a tapered thick composite plate. The governing differential equation of motion of the various tapered configurations of a thickness tapered reinforced composite plate are presented in the finite element method using first order shear deformation theory. The failure analysis is carried out by considering the fact that the crack exits parallel to the fibers when the ply fails and the cracked ply is being replaced by a hypothetical ply that has no transverse stiffness, transverse tensile strength and shear strength. However, the longitudinal modulus and strength is considered to remain unchanged. First the local stress and strains in each ply is found out under various loading conditions. Then by employing the ply-by-ply stresses and strains in failure theories, the strength ratio is calculated. Multiplying the strength ratio to the applied load yields the load level of the failure of the first ply. Once the first ply failure load is evaluated, the stiffness of the damaged ply or plies is degraded and the actual load level of the previous failure is considered in further calculation. The strength ratios of the remaining undamaged plies are evaluated at each level of loadings. Thus the degraded stiffness of the tapered composite plate from first ply failure to last ply failure under various loading condition are investigated
