Fast two-scale computational model for progressive damage analysis of fiber reinforced composites

A fast two-scale finite element framework based on refined finite beam models for progressive damage analysis (PDA) of fiber reinforced composite is presented. The framework consists of a macroscale model to define the structural-level components, interfaced with a second sub-scale model at the fiber-matrix level. Refined finite beam elements are based on Carrera Unified Formulation (CUF), a hierarchical formulation which offers a procedure to obtain refined structural theories that account for variable kinematic description. The representative volume element (RVE) at the subscale is modeled with real material, e.g., fiber and matrix with details about packing and heterogeneity. Component-Wise approach (CW), an extension of refined beam kinematics based on Lagrange-type polynomials is used to model the constituents in the subscale. Each constituent in the subscale is modeled by the same finite element in the framework of the CW. The energy based crack band theory (CBT) is implemented within the subscale constitutive laws to predict the damage propagation in individual constituents. The communication between the two scales is achieved through the exchange of strain, stress and stiffness tensor at every integration point in the macroscale model. The efficiency of the framework is derived from the ability of CUF models to provide accurate three-dimensional displacement and stress fields at a reduced computational cost (approximately one order of magnitude of degrees of freedom less as compared to standard 3D brick elements). Numerical predictions are validated against the experimental results.