Structural Seismic Response Fuzzy Control Considering Optimal Actuator Placement

Earthquake is one of the main natural disasters faced by human society.It's a common issue for the people worldwide to improve the seismic performance of building structures in order to reduce the damage caused by earthquakes to human society.Increasing structural vibration control theories raised provide new methods for improving the seismic performance of structures which have been proved to be effective.Therefore,it is of great significance to study the seismic response control of structures and develop the vibration control theory for improving the seismic performance of structures.From the perspective of economy,actuators are only arranged on some floors of the structure,which makes it difficult to obtain the optimal actuator placement,and the actuator placement has a significant impact on the vibration control effect of the structure.Therefore,it is necessary to study the optimal actuator placement.When a structure is subjected to earthquake,the structural parameters often change,which makes the classical control algorithm relying on specific structural parameters difficult to apply.Fuzzy control does not depend on specific structural parameters,and can make control force according to structural response,which makes it highly suitable for structural seismic response control.However,in the design of fuzzy controller,the selection of membership function and control rules depends on human experience,and it is difficult to obtain the best control effect.Concerning the problems above,the following research work has been carried out in this paper:(1)Actuators based on single-order modal strain energy criterion can only well control the vibration of a certain mode of the structure.In view of this shortcoming,this paper considers the influences of different modes,and proposes an optimal actuator placement criterion based on comprehensive modal strain energy,which is applied to the optimal actuator placement of Benchmark model.(2)Based on Benchmark model,the distribution of structural modal strain energy is analyzed,and the relationship between the number of actuators and control effect is analyzed from the energy point of view.The number of actuators is optimized to reduce the number of actuators needed for vibration control.(3)In view of the shortcomings of membership functions and control rules selection of fuzzy control,this paper combines fuzzy control with genetic algorithm,and puts forward the optimization criterion of fuzzy control which combines the root mean square of displacement response and the root mean square of acceleration response.The membership functions and control rules of fuzzy control are optimized by genetic algorithm.(4)According to the optimal arrangement of actuators and the optimal result of fuzzy control,the fuzzy control simulation of structural seismic response is carried out with four kinds of seismic waves as input respectively.The control effect of fuzzy control on structural seismic response is studied,and the effectiveness of the optimization criterion of fuzzy control proposed in this paper is verified.The simulation results of structural seismic response control show that the actuators optimized based on the actuator optimal placement criterion proposed in this paper can achieve better control effect than the actuators without optimal placement,which verifies the effectiveness of the actuator placement criterion based on comprehensive modal strain energy proposed in this paper.According to the fuzzy control optimization criterion proposed in this paper,the fuzzy controller is optimized by genetic algorithm.The fuzzy controller can effectively reduce the seismic response of the structure under the input of different seismic waves,and can achieve better control effect than the unoptimized fuzzy control,which shows that the optimization criterion of the fuzzy control proposed in this paper is effective.