A three-dimensional finite element analysis treating the nonlinear viscoelastic response of laminated composites is presented. The individual plies in the laminate are modeled using 20-node isoparametric solid elements. The transient creep compliance in the viscoelastic model is represented as an exponential series plus a steady-flow term, which allows for a simplification of the numerical procedure for handling hereditary effects. Time-dependent stress and strain distributions are calculated for unnotched and notched laminates subjected to tensile loading or bending.
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