Engineering analysis of a critical RC straight girder bridge under contact blast in reducing dynamic impact and failure using the FEM-SPH coupling and non-Explosive Reactive Armour

Worldwide terrorist activities have been increasing rapidly, particularly over infrastructure, which strongly demands the identification of failure modes, dynamic response, risk assessment and prevention. Research has continuously improved the shaped charge and ballistic-resistant performance of the structures. Literature updates show that the right material choice may help to achieve the goal. Therefore, the present study selects an existing 20.4 m full RC straight highway girder bridge, over which one layer of the steel-based non-Explosive Reactive Armour (nERA) has been wrapped as protective material using surface-to-surface contact to explore its effect on reducing failure mode and dynamic response of the bridge under contact blast using computer simulation through the coupling of the Finite Element Method (FEM) and Smoothed Particles Hydrodynamics (SPH). In addition, 54 explosives have been applied over the top surface of the approach slab, the earth's surface at footing level enclosed by both abutments and the top and bottom surfaces of the deck. Specifically, the analysis concentrates on the Damaged contours and shock wave propagations, Damaged contours and particle formation, Effective plastic strain (EPS), Direct damage-reduction of the bridge, and Failure modes. Finally, the effect of the nERA is significantly positive in reducing failure mode and improving the dynamic response.