Progressive failure of laminated composites with a hole under compressive loading based on micro-mechanics

This paper deals with progressive failure analysis of composites structure on the basis of the theory of micro-mechanics of failure (MMF). The MMF theory includes micro-scale stress amplification within each constituent material (fiber and matrix) and failure criteria for the judgment of the constituent failure. The unit cell model with the face-centered array distribution of carbon fibers is constructed to analyze the micro-scale stress amplification factors in the fiber and matrix. Noninteractive failure criteria are proposed to judge the failure of the fiber and matrix. During the process of loading, the constituents’ failure can be identified by the MMF failure criteria, and then the material properties degradation scheme is evaluated according to the failure modes of constituents and applied for each element to continue the progressive failure analysis for the composite materials. The user-defined material subroutine for the micro-scale stress amplification in the constituents, failure judgment of the constituents, and degradation of ply properties is developed using the Abaqus Fortran scripts. Micro-scale stress of the constituents is visualized for detailed analysis. The initial failure, subsequent propagation, final failure, and the strength of open-hole compression (OHC) structure of the carbon fiber-reinforced polymer composites are studied based on MMF theory. The ultimate load and failure behavior of the OHC structure obtained from both theoretical analysis and tests are compared and analyzed.