Numerical analysis of foam-protected RC members under blast loads

Abstract

Due to the threat of terrorist activities worldwide, research on the protection of building structures from the effects of explosions is critical in order to avoid catastrophic damage to buildings. Protecting our infrastructures means protecting lives. Metallic foam is an economical, light-weight and recyclable material used as a sacrificial cladding to protect structures. Its efficient energy absorption enables metallic foam to mitigate the blast energy acting on the protected structure. This paper describes our numerical investigation of the protective performance of metallic foam cladding on reinforced concrete (RC) structural members using LS-DYNA. In the numerical model, Modified Honeycomb (Material 126) from the LS-DYNA material library was used to represent the aluminium foam while Continuous Surface Cap Model (Material 159) was selected to model the behaviour of concrete. The numerical model was validated by field blast testing results. Using the validated numerical model, parametric studies were conducted to assess the influence of different foam properties on the pressure-impulse (P-I) diagrams of the foam-protected RC slabs. The influence of the thickness of the RC members was also investigated. The derived P-I diagrams will prove useful in the preliminary design of the foam cladding on RC members.