Influence of spatially varying ground motions on the seismic responses of bridge structures with KDampers

KDamper has been applied to control the seismic responses of bridge structures very recently. However, previous studies considered its performance under uniform ground motions only, the influence of the inevitable spatially varying ground motions (SVGMs) is not yet explored. To address this issue, this study systematically investigates the seismic responses of a large-span bridge structure equipped with KDampers subjected to SVGMs. In particular, the analytical model of a classical bridge equipped with KDampers is developed, and the corresponding dynamic equations of motion are formulated. Subsequently, KDampers are optimized by minimizing the mean peak response of the bridge deck in the frequency domain. Finally, parametric analyses are performed to comprehensively evaluate the influence of SVGMs (including wave passage and coherency loss effects) on the seismic responses of the bridge in both the frequency and time domains. The analytical results reveal that the optimized KDampers are effective in reducing the displacement and absolute acceleration responses of the bridge. Moreover, the effectiveness of KDampers is more evident when SVGMs are considered as compared to the uniform ground motions. This research can contribute to an in-depth understanding of the control effectiveness of KDampers, especially for the cases considering SVGMs.