Seismic Performance Analyses Of The Piezoelectric Friction Damper Based On Intelligent Control Algorithms

With the development of'intelligent'technology,'intelligent'has been widelyinfiltrated into various sectors.Structural vibration control combining with the'intelligent'technology forms structural intelligent control.Generally,structuralintelligent control includes two aspects: first, intelligent control uses intelligentcontrol algorithm, marked with the use of control algorithm, such as fuzzy control,neural network control, genetic algorithm, etc; the second is intelligent controlsystems formed by smart drive or intelligent damping device, marked with the use ofintelligent materials or devices, such as piezoelectric materials, electrical/magneticrheological fluid, electric/magnetostrictive materials and shape memory materials, etc.In this paper, these two aspects are combined, that is to say the piezoelectric ceramicactuator combines with the friction damper, to form a smart damping device, andstudy the vibration resistance of this device.The main contents of this article have:(1) Use two types piezoelectric ceramic actuators separately combining with anordinary friction damper to form piezoelectric friction dampers. Some relatedexperiments are done to test the response time, the speed of response, output ability ofthe two piezoelectric ceramic actuators and the piezoelectric friction damper.Theexperimental result indicates that the response times of the two actuators are short, thespeeds of response are quick, output ability is slightly small; the response time ofpiezoelectric friction damper lags behind the response time of the actuators, and thepossible reasons causing this situation are analyzed.(2) The T-shaped core plate friction damper instead of ordinary friction dampercombines with the bigger piezoelectric ceramic actuator to form a piezoelectricfriction damper, which is installed in a steel frame structure. Some experiments aredone to study the hysteretic behavior of the damper in actual framework.Experimental results show that the damper's hysteresis curve is stable, full andhysteretic behavior is good, which indicates that the damper has a better energy dissipation performance.(3) A vibration isolation system is composed by the piezoelectric friction damperand rubber isolation pads, to study its seismic resistance effect on the structure underthe simulation with different intelligent control algorithms. Comparing the seismicresistance effect under different algorithms, the effect of fuzzy control is focused inthis paper. The simulation is based on the Bohai Sea JZ20-2MUQ offshore platformstructure, and the simulation results show the system can greatly reduce the vibrationresponse of offshore platform structures with obvious seismic resistance effect.Theseismic resistance effect of fuzzy control algorithm is close to active control algorithm,which shows the fuzzy control force can track the active optimal control force well,demonstrating the superiority compared with other control algorithm.(4) Propose two methods to optimize fuzzy control: neural networks, geneticalgorithms, since fuzzy control has a number of defects(eg. the determination ofmembership is difficult, the control rules rely on experts'experiences). The basicprinciples of neural network technology and genetic algorithm are introduced, andsome simulationes about fuzzy control optimized by genetic algorithm have beendone, the results show the optimized fuzzy control is more effective thannon-optimized fuzzy control.