Seismic Reduction Analysis Of Isolated Structure Basedd On Frog Leaping Fuzzy Algorithm Under Near Fault Earthquake

How to improve the safety of structures under the action of earthquake is a hot topic in civil engineering research.Base isolation can effectively reduce the response of the structure under the earthquake,but the displacement of the isolation layer will increase obviously under the earthquake,especially under the attacked of near-fault ground motion.This paper takes the seismic isolation structure as the research object,combines piezoelectric friction dampers with the base isolation layer,and uses the proposed leapfrog-fuzzy control strategy to adjust the output voltage of the piezoelectric friction dampers in real time to better reduce the vibration of the seismic isolation structure.The main research contents are as follows:(1)According to the working characteristics of the variable friction damper,a semi-active control strategy based on the shuffled frog leaping algorithm and fuzzy control is proposed to control the piezoelectric friction damper,and input the speed and displacement of the isolation layer into the fuzzy controller.The frog leaping algorithm is used to optimize the fuzzy control rules and output the control voltage to realize the real-time adjustment of the control force of the piezoelectric friction damper.(2)Establish the mechanical model of the piezoelectric variable friction damper and the seismic isolation support,and the theoretical analysis model of the seismic isolation structure.According to the seismic characteristics,select the pulse type,non-pulse type and far field ground motion,and use the proposed leapfrog-Fuzzy control strategy for seismic analysis of isolated structures.(3)Carry out the seismic reduction analysis of the seismic isolation structure,and compare the seismic reduction effects of the leapfrog-fuzzy control strategy under the action of different types of earthquakes.The results show that the proposed leapfrog-fuzzy control strategy can reduce the displacement of the isolation layer and the acceleration response of the top layer,and it has good adaptability under the action of earthquakes of different intensities.