LAUSR

Abstract High velocity impact response of quasi-isotropic carbon fiber reinforced polymeric laminates cured from unidirectional plies is studied using finite element models. Rigid steel spheres are used as projectiles. The intraply meso-model originally proposed by Ladeveze (LMT-Cachan) for the ply behavior based on continuum damage mechanics, is extended in this paper to take into account ply fracture energies and in-situ strengths. Constitutive modeling relies on mesh size regularization (via Bazant-type crack-band/smeared-crack formulation), orthotropic material aligned mesh and element erosion. Three different types of post-peak degradation strategies are considered and compared in the paper: (a) damage rate bound model, and smeared-crack formulation based (b) linear and (c) exponential softening laws. Models (b) and (c) are original contributions. Intraply and interply damage models are implemented via user routines in LS-Dyna, for explicit dynamic analyses. The efficiency of the novel material models to predict high velocity impact response and to mitigate the mesh size effects is studied. Predictions from the developed models are validated by comparing with test data and numerical results from the literature, and demonstrated that the two new models based on smeared-crack formulation provide accurate results.