Computational Modeling of Damage and Failures in Composite Laminates

Abstract

Abstract This chapter is intended to provide an overview of issues that are important in the computational modeling of progressive damage and failure in fiber‐reinforced composite laminates. Owing to space limitations, the discussion mainly focuses on those models and methods that have been effectively used by the authors to address this particular class of problems, with references given to other viable models and methods. Topics covered in this chapter are as follows. An introduction and overview of fiber‐reinforced composite laminates, with emphasis on the multiscale nature of this class of materials, is presented in Section 1. Section 2 contains an overview of mathematical models that are commonly used to represent the mechanical behavior of composite laminates. These models constitute a natural hierarchy of models ranging from the simplest two‐dimensional plate model that only represents in‐plane behavior to a fully three‐dimensional layerwise model that includes discrete layer transverse shear and transverse normal effects. In Section 3, an overview of damage and failure models that have been used for composite laminates is presented. Discussion of the coupling between the macroscale and the microscale is presented in Section 4. This micro/macro coupling is achieved through the processes of homogenization and localization . Homogenization is the process of determining homogeneous anisotropic material properties that effectively represent the average behavior of the heterogeneous fiber/matrix composite material. Localization is the process of determining the microscopic distribution of stress and strain based on a known macroscopic solution. These topics are discussed in the context of both infinitesimal and finite deformation. Finally, Section 5 is devoted to the description of possible approaches for the modeling of progressive damage. In particular, the discussion focuses on the application of continuum damage mechanics to the homogenized material description used for individual composite laminae. This particular methodology is chosen on the basis of its computational practicality coupled with its ability to describe stiffness reduction to a level of accuracy that is sufficient for a large class of problems. The last section, Section 6 (new with this volume), is concerned with the use of simultaneous, multiple laminate models in simulating progressive damage and global collapse of laminates subjected to combined bending and transverse shear deformation.