研究期間：10108~10207;Lately, modern bridge seismic design has been developed toward the seismic performance design on entire bridges as well as components thereof. Although it is easy to understand the performance regulations or goals in performance-based design, it is still an open issue if a bridge can achieve the performance goals under ultimate situation. In the past decade, a number of bridges suffered damage even collapse due to earthquakes, floods or debris flows in Taiwan. Some damaged bridges are still in service. Actually, the structural properties of these bridges which suffered from scouring or debris flows have changed with the change of the clear height of the piers. Therefore, it is also an open issue if these bridges can survive when the next extreme earthquake occurs. Recently, we have successfully developed the structural control technology by using sliding mode control for reducing the nonlinear behavior of structures under large earthquakes and the numerical analysis method by using Vector Form Intrinsic Finite Element (VFIFE) for simulating and predicting the ultimate condition of bridges under extreme ground motions. Based on the results, the ultimate analysis method and the structural control technology will be continuously developed to be applied to the bridges suffered from scouring or debris flows as well as the bridges with inclined decks. From the viewpoint of ultimate collapse, it is aimed to study the seismic performance and the ultimate failure mode of the target bridges with pounding effects and to clarify the failure sequence of the structural components, such as bearings, columns, and unseating prevention devices. According to the results of numerical simulations, the design of bearings and unseating prevention devices of bridges with pounding effects will be investigated. In addition, a hybrid optimum searching algorithm will be utilized to obtain the optimum parameters of the sliding surface in the sliding mode control. It is expected to improve the seismic performance of the floor-damaged bridges. Shaking table testing will be conducted for model bridges with semiactive control to clarify the practical implementation. Finally, the ultimate condition of the floor-damaged bridges with pounding effect and structural control will be examined by using the VFIFE.
