A new strategy for restraining seismic response of highway bridges

In order to solve the difficult problem that traditional fuzzy logic control (FLC) strategy shows dissatisfactory control effect when facing different control objectives and load actions, this paper proposes a variable universe-based self-adaptive fuzzy control strategy (VAFC) theory. This strategy improves the performance of the FLC strategy by adjusting the universe of FLC input and output variables online, and designs the self-adaptive law of output universe based on Lyapunov function. This paper introduces modified clipped-optimal (MCO) into VAFC active control strategy and puts forward VAFC/MCO semi-active control strategy. In this paper, seismic responses of three-span continuous girder bridge under the control of VAFC/MCO, FLC/MCO and LQG/MCO are analyzed respectively, and the results show that the VAFC/MCO strategy has more significant seismic reduction effects than the FLC/MCO and LQG/MCO strategies do.