Numerical Modelling For Reinforced Concrete Response to Blast Load: Understanding The Demands On Material Models

Abstract

Synopsis : Numerical modelling is nowadays commonly employed in the analysis of concrete structures subjected to extreme dynamic loadings such as blast. Sophisticated material models, particularly concrete, are available in commercial codes and they are often applied in their default settings in a diverse range of modelling applications. However, the mechanisms governing different load response scenarios can be characteristically different and as such the actual demands on specific aspects of a material model differ. It is therefore not surprising that a well-calibrated material model may exhibit satisfactory performance in many applications but behave unfavourably in certain other cases. Modelling the response of reinforced concrete structures to blast load presents such an important scenario in which the demands on the concrete material model are considerably different from high-pressure scenarios for example high-velocity impact or penetration. This paper stems from an initial modelling undertaking in association with the Blind Blast Contest organised by the ACI Committee 370, and extends to a detailed scrutiny of the demands on the concrete material model in terms of preserving a realistic representation of the tension/shear behaviour and the implications in a reinforced concrete response environment. Targeted modifications are proposed which demonstrate satisfactory results in terms of rectifying the identified shortcomings and ensuring more robust simulation of reinforced concrete response to blast loading.