Abstract:To improve the seismic performances of bridges with very tall piers in high seismicity area, design concept of the bridge with very tall piers, which is composed mainly of concrete-filled steel tubular (CFST) columns and energy dissipating mild steel plates (EDMSP), is proposed based on the principle of earthquake restorable structures. Trial design of a bridge with the proposed innovative composite box section tall piers is carried out based on a typical continuous rigid frame highway bridge with tall RC box section piers. The static and seismic performances of the bridge according to fundamental loading combination and E2 level seismic action are analyzed respectively. The seismic performance of the designed bridge under E2 level seismic action is compared with the bridge with conventional RC box section piers. The results show that: (a) under fundamental loading combination, the bridge with innovative composite box section piers can well meet the requirements of structural strength and stability; (b) under E2 level seismic action, the conventional designed bridge experiences medium damage in the piers, while only the replaceable EDMSP elements of the innovative designed bridge undergo plastic deformation, indicating the innovative designed bridge is earthquake restorable; (c) the seismic displacement responses of the innovative designed bridge is significantly smaller than that of the conventional designed bridge under E2 level seismic action.