Finite Element Analysis And Experimental Study On Active Vibration Control Of Single-layer Reticulated Shell

With the development of society, the latticed shell is applied more widely, so under the earthquake and wind loads, the vibration control problem of latticed shell has become more and more prominent and urgent.Piezoelectric material has the performance of the direct and converse piezoelectric effect ,. can be used as sensor and actuator. In long-span spacial steel structure how to make full use of piezoelectric materials active control of piezoelectric effect has already become an important research hotspot. In order to control vibration of the latticed shell by piezoelectric materials,a study is made on the finite element analysis and the shaking table test of the single layer latticed shell active vibration control by finite element analysis and vibrating table tests methods,the main research work is as follows:(1) The finite element analysis is done in the 9 kinds of single-layer kay witter latticed shell which has the span of 25m,35m,45m and the rise-to-span ratios of 1/3,1/4,1/5 by ANSYS12.0. Seismic wave is executed the quantifying analysis to seismic wave by fourier transformed in this paper and the model of quantitative analysis is also established. This paper analyzes the 54 species of conditions to horizontal earthquake effect of Lanzhou seismic waves, EL-Centro seismic waves and Taft seismic waves. Structure vibration response laws and dynamic characteristics are obtained.(2) Piezoelectric actuators active rods was designed and manufactured which has already obtained a invention practical patent.The dynamic and driving characteristic tests are carried on the 8 piezoelectric actuators , vibration frequency of piezoelectric actuators is analyzed,and the major factors of drive performance are discussed,and the relations between the driving voltage and the gain driving force are analyzed.The test results show that piezoelectric actuator has linear driving performance , with frequencies in the approximate range of 5 to 50 hertz,so it can applied to the active control in civil engineering structure(3) Piezoelectric active control strategies of single-layer spherical lattice shell is analyzed , and the finite element equations of Piezoelectric active rods are calculated.This paper establishes the finite element equations of the K8 single-layer spherical lattice shell which assemble piezoelectric active rods,and also introduces independent modal control algorithm. The results show that the modal control is applicable to the piezoelectric active control of the single-layer spherical lattice shell.(4) The K6 single-layer spherical lattice shell model which assemble piezoelectric active rods is designed and made. The numerical analysis and the earthquake simulating shaking table test are performed which contains 58 species conditions. The numerical simulation results and experimental results are analyzed,and the main influence factors on control effect of piezoelectric active rods is discussed. The results show that the piezoelectric drive can effectively restrain the vibration response of the single-layer kay witter latticed shell.This paper shows that making sufficiently used of piezoelectric materials superior properties, reasonable application of the active control strategies in the space steel and active vibration control by using piezoelectric class driver is important theoretical significance to resolve vibration and dynamic instability problems in long-span spacial steel structure. It is widly prospect of application and practical value.