Blast Loading Effects on an RC Slab-on-Girder Bridge Superstructure Using the Multi-Euler Domain Method

Recently, increasing terrorist threats on bridges have illustrated the vulnerabilities of this type of transportation infrastructure. Because of cost and safety constraints, it is impractical to obtain the complete structural response by testing a real bridge, so in recent years, a fully coupled fluid-structure interaction model, which still has several assumptions, was developed to simulate the blast wave propagation process and its interaction with the structure; this has become an advanced method to better analyze blast loading effects. However, because of the complicated computational algorithm and desktop computer resource limitations involved in using this model, it is not practical to simulate large structural responses, especially for long-span bridges. The purpose of this paper is to develop a multi-Euler domain method to solve the problems listed earlier. Both the verification of the method and its application for a RC composite slab-on-girder bridge proved its accuracy and efficiency. The blast-resistant capacity of three different detonation scenarios was investigated, including one above-deck detonation and two under-deck detonations, with different trinitrotoluene (TNT)-equivalent charge weights. This study established the dynamic performance and the damage mechanisms of the whole bridge and identified the critical blast event for this typical slab-on-girder bridge. The results and observations of this study provide a global understanding of protection strategies for highway bridges.