Title: Comparative Study of Concrete Constitutive Models for Predicting Blast Response

Author(s): James W. Wesevich, David D. Bogosian, Barry L. Bingham, Johan Magnusson, and Alexander P. Christiansen

Publication: Symposium Paper

Volume: 281

Issue:

Appears on pages(s): 1-18

Keywords: concrete, constitutive, model, blast, deflection, slab, response, shock, tube, test

DOI: 10.14359/51683609

Date: 12/27/2011

Abstract:
The robustness of concrete constitutive material models in explicit finite element codes is typically measured by their ability to match peak dynamic and permanent displacements of a reinforced concrete specimen. In a series of recent shock tube experiments, reinforced concrete slabs were subjected to simulated blast loads. Applied pressure histories were recorded in these tests, as were peak and residual displacements. This paper evaluates the Concrete Damage Model (Material 72, Release 3) and the Continuous Surface Cap Model (Material 159) within LS-DYNA (Version 971), as well as the Applied Engineering Cap model (AEC-3I) in DYNA3D. The results indicate some variation in predicted damage and failure modes between the three material models, but overall, all three models produced satisfactory comparisons to the test with regard to peak positive deflection (i.e., within a factor of 2 of the measured response). A surprising outcome is that the inclusion of rate-dependent material properties actually increased the error in the predicted response. In terms of predicting crack patterns, the AEC-3I model appears to be preferable, whereas MAT72R3 is preferred for predicting peak deflection. Overall, MAT159 was the most consistent predictor and the least sensitive to variations in the rate dependent properties of concrete.