Seismic performance of skewed bridges with simultaneous effects of pounding and supporting soil

摘要

Some of the factors that are known to significantly affect the seismic response of bridges include bridge pounding and the influence of the supporting soil. For skewed bridges, the skew angle is another crucial factor. Although some studies on this topic have been done, most have been numerical. Experimental work has been scarce. Furthermore, none has considered the factors simultaneously. This study aims to bridge this gap in knowledge by conducting shake table experiments on a straight, 30 degrees, and 45 degrees bridge considering bridge-abutment pounding and soil support, separately and simultaneously. In most cases, the effects of pounding and soil support simultaneously can be seen as a combination of the effects of each factor separately. However, with a 45 degrees skew angle, when pounding and supporting soil were considered separately, the bending moments near the base of the piers were increased compared to the idealised fixed base case without considering pounding. When both factors were considered simultaneously, the opposite was observed. In addition, in the transverse direction, the relative displacement of the girder would always be significantly underestimated if the assumption of fixed base and no pounding was adopted.