Damage analysis of prestressed small box-girder bridge under explosive vehicle load

Bridges are essential for regional traffic and economic development. Damage to a bridge due to terrorist attack or accidental explosion can cause severe losses and impacts on whole cities and regions. In order to analyse the response and failure of a small box-girder bridge under automobile explosion, explosion simulation tests on the deck and main girder at the bearing part, quarter span and half span were conducted. The explosion conditions for eight standard vehicles were then compared. It was found that damage to the bridge under explosive load was mainly along the longitudinal direction of the bridge, and the change of the explosion point along the longitudinal direction of the bridge significantly impacts the bridge deck breach. When the explosion occurs above the box girder, the response of the box girder is about 1.5–3.0 times that of the bridge deck. The damage to the superstructure of a prestressed small box-girder bridge under a typical vehicle explosive load is localised.