Effect of simultaneous spatial near-source ground excitation and soil on the pounding response of bridge girders

The study addresses the influence of the characteristic of the near-source Kobe earthquake, the spatially varying ground motions, and the soil-structure interaction on the pounding response of two adjacent bridge frames. For the simulation of the non-uniform ground excitation of the bridge piers the Japanese design spectrum for soft soil is used. The numerical result of the investigation of the simplified model reveals that -depending on the ratio of the natural frequencies of the two adjacent structures- soft soil can cause a strong amplification of the pounding forces on structures. When their natural frequencies are close to each other non-uniform ground motions may significantly increase the relative structural responses. The result of the finite-element and boundary-element model confirms the significant effect of the spatial ground excitation and the soil-structure interactio