Consequence of Slenderness for the Seismic Response of Rockable Bridges

Research has shown that the transient and partial footing separation can significantly reduce the seismic loading transmitted from the ground into structures. Therefore, allowing footing to rock becomes a possible low-damage design approach. Till now, experimental research on the dynamic of rockable bridges has been very limited. The present study aims to provide a better understanding of the consequence of slenderness on the dynamics of rockable bridges by conducting large-scale shake table tests. To limit the number of influence factors and to better explain the results, the footing was only allowed to rock on a rigid support, and pounding between adjacent bridge members was intentionally ignored. The results demonstrate the significant role of bridge slenderness in overall bridge responses. This bridge behaviour cannot be observed in the case of a commonly assumed fixed-base support since the slenderness effect cannot be activated.