Comprehensive optimal control on seismic response of a single-tower self-anchored suspension bridge

Earthquake may cause severe damage to all kinds of bridge such as the falling down of the girder; therefore, effective measures should be employed to control the seismic displacement. In this paper, the method of comprehensive optimal control, combined with analytic hierarchy process, is employed to investigate the seismic response control of the Nanjing Jiangxinzhou Bridge, which is a single-tower self-anchored suspension bridge (SSSB). Also, 3-dimensional nonlinear seismic response analyses are conducted. Three types of practical connection measures for seismic response control of SSSB are investigated, and the optimal parameters of the connection devices are achieved by this method. Results show that both the elastic connection devices and the dampers with rational parameters can reduce the seismic displacement of the bridge effectively, but the elastic connection devices will increase the seismic force of the tower. When all factors are considered, the optimal measure is by using the elastic connection devices and the dampers together. These results can provide references for seismic response control of SSSBs.