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The behavior of a woven E-glass–Vinylester composite in dry and seawater-saturated conditions was investigated for strain rates in the range of 0.001–100 s−1. Reliable data were obtained by conducting servo-hydraulic tests at high speed with DIC strain measurement. Issues related to inertial effects of the test system and controlling vibrational stress waves were resolved through a unique experimental setup and special attention to specimen geometry and fixturing. In addition, a rate-dependent constitutive model was adapted to characterize the elastic–viscoplastic response at various strain rates and validated by comparison to test data. The subject investigation demonstrates a viable methodology to identify strain rate sensitivities in high speed experiments and develop a representative material model for analysis of high rate phenomena. [ABSTRACT FROM AUTHOR]

Abstract: A progressive failure approach, applicable to woven polymer-based composites is developed and validated with experiments. Constitutive equations are formulated to characterize the mechanical response for fully non-linear, rate dependent, anisotropic behavior under dynamic loading. A mechanistic fiber failure theory is implemented, while a degradation model describes the stiffness reductions after failure. The approach is implemented in the Abaqus finite element code using a user material subroutine (UMAT) that defines the constitutive theory and implements the progressive failure methodology. The progressive failure approach is validated using basic tension and open hole tension experiments. The tests are performed using digital image correlation, which provides the complete non-uniform strain and displacement fields. The validation testing has included cases involving large deformations, where strains to failure are as high as 20%. The simulation results are in good agreement with experimental data. [Copyright &y& Elsevier]