Development of the impact force time-history for determining the responses of bridges subjected to ship collisions

摘要

Ship impact force is usually taken as an equivalent static force in current bridge design, which is, however, limited on effectively capturing the dynamic amplification effects. To this end, this work proposes a simplified analytical model for predicting the time-history of ship impact loading on bridges. To validate the FE modeling techniques used in capturing the impact loading, drop hammer impact tests are carried out using scaled steel boxes. Then FE models of 5 typical ships are developed and numerical simulations are conducted to generate the 45 benchmark impact force time-history curves which are used to determine the parameters introduced in the proposed simplified analytical model. The efficiency of the proposed model is evaluated by a case study involving two bridge models, as presented in this paper. It is shown that the proposed simplified analytical model is capable of predicting the time-history of impact loading with sufficient accuracy for ship-bridge collision events when the basic structural frequency of the bridge pier is within 3 Hz.