Development of Three-Dimensional Finite Element Method for Composite Materials Based on Damage Mechanics

A computer program of the three-dimensional finite element method for composite materials based on damage mechanics has been developed. There are many kinds of fracture pattern in composite materials. Especially, the progression of fracture caused by out-of-plane and shearing deformation is very complex. The effect of these fracture patterns on the mechanical behavior must be considered for the design and analysis of fracture behavior of composites. The consideration of damage mechanics has been introduced into the proposed program in order to treat above mentioned behaviors. A numerical procedure with new concept for the constitutive equation with damaged elements is introduced in this paper. As an example, the mechanical behavior of laminate under three point bending was analyzed by the developed computer program. The computational results concerning the fracture pattern agreed well with the experiments. Consequently, it can be recognized that our proposed program is very useful for structural design and analysis of mechanical behavior for composite structures.