Semi-Active Control with Photostrictive Actuator for Railway Bridges Based on Adaptive Fuzzy Control Algorithm

To reduce the large displacement of both bearing and girder in regard to seismically isolated railway bridges after the earthquake, the photostrictive actuator (PA) was used as a control device, and the adaptive fuzzy control algorithm (AFCA) was designed based on the Lyapunov stability theory. Combined with the clipped optimal control algorithm (COCA), Matlab program of AFCA & COCA semi-active control algorithm for PA was developed. The uncontrolled bridges and bridges controlled by LRB were contrastively analyzed by using AFCA & COCA semi-active control algorithm and AFCA active control algorithm, respectively. The results indicate that the AFCA & COCA semi-active control strategy and AFCA active control strategy can effectively reduce seismic responses of both uncontrolled bridges and bridges controlled by LRB. The semi-active control strategy and active control strategy can effectively reduce the large displacement of both bearing and girder for seismically isolated bridges. The control force curve of semi-active control strategy is in good agreement with the curve of active control strategy, and the control light intensity applied to the top or left and the bottom or right of PA are within the admissible range.