This study addresses the influence of spatial variation of ground movements at the pier support and abutments on the bridge responses with non-linear bearings. To focus on this influence factor the spatially varying ground motions caused by incident waves of a Ricker waveform with single dominant frequency propagating into the bridge site of a shallow-trapezoidal valley are chosen. The considered parameters are: the incident angle and the dominant frequency of the incoming waves. The investigation reveals that although girder responses with movable abutments and without abutment impediment are similar, a neglect of the abutment impediment and an assumption of fixed abutments can underestimate not only pounding forces at the ends of bridge girders, but also shear forces at the bearing supports. Inclined incident waves must not necessarily produce larger bridge responses, because vertically propagating waves cause also spatially varying ground excitation, and their almost equal large amplitudes can cause larger structural responses. |
