Simulations of Concrete Response to Impact Loading Using Two Regularized Models
This paper focuses on a comparison of two regularized continuum models for concrete in the simulations of selected benchmarks of response to impact loading. Their overview is performed in the context of application in dynamics. The first one is the Hoffman viscoplastic consistency model, where the strain rate activates regularization. The second model is derived from the scalar damage theory enhanced by an averaging equation incorporating the Laplacian of an averaged strain measure. Both models are implemented in the FEAP package. The results of some standard wave propagation tests are discussed, considering discretization sensitivity and predicted failure modes. Three examples are presented: the direct tension of a plain and reinforced concrete bar, the split test of a cylinder, and the four-point bending of a reinforced concrete beam. The ability of both models to simulate impact loading is assessed.
Keywordsdynamics, viscoplasticity, damage, concrete, regularization, finite element method,
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