Model Test And Theoretical Analysis On The Seismic Response Of Space Truss Structure Control Based On SMA

Shape memory alloy(SMA) is a new functional material, which has many uniquematerial performance, such as the super elastic effect, shape memory effect, high damping andmodulus properties, use its special mechanical behavior and physical properties, make itbecome the control device is applied to the structural vibration control in engineering field,will certainly show obvious advantages and broad prospects, the research analysis of vibrationcontrol of structure on the application of SMA, laying a solid theoretical foundation for thepromotion and application of SMA of this kind of intelligent material, will produce theenormous economic benefits and social benefits.In this paper, by using the SMA elastic performance and shape memory propertiesunique, developed SMA passive, active/passive hybrid control system based on control theory,proposed and strategies, and the computer simulation and shaking table test is conducted. Themain work and research contents include:(1)Using the computer and servo controlled material testing machine, the mechanicalproperties of the 13 groups of 52 austenitic and 10 group of 30 martensitic shape memoryalloy materials were performed in, through changing main parameters, the stcurrent, loadingamplitude, loading rate, cycle number and diameter, studying the restoring forcecharacteristics of shape memory alloy materials, results show that the loading the amplitudeand loading rate is an important parameter affecting the austenitic material characteristic ofrestoring force, current and load amplitude is the main factor affecting the restoring forcecharacteristics of martensitic materials.(2)Based on the material test and numerical analysis results, the Brinson constitutivemodel as the foundation, by using the computer simulation method, the loading rate andloading amplitude factor were led in, we put forward 3 kinds of high precision, piecewiselinear shape memory alloy restoring force constitutive model, and determine the main featuresof the constitutive model of value, provide experimental and theoretical basis for furtherresearch.(3) Using genetic algorithm to optimize the BP neural network, the nonlinearconstitutive model of shape memory alloy material with prediction function, high precisionand suitable for the dynamic response is established. Aiming at the vibration control theorystudy and engineering application are concerned, using genetic algorithm to optimize designthe controlled space truss structure, studying on the effect of control optimization on the spacetruss structure of the location system and set the number of shape memory alloy, to realize thewhole optimization control of space truss structures.(4)Using the Matlab language programming, the system computer simulation programof space truss structures under earthquake is not controlled, the shape memory alloy control isset of random and optimization setting was designed, according to the characteristics ofmartensitic shape memory alloy, Mamdani fuzzy control, fuzzy Sugeno control and thecontrol strategy were studied, put forward a kind of new the control strategy, the triggerswitch control strategy, using Matlab language, design the simulation analysis program ofspace truss structure with trigger switch control strategy, considering the genetic algorithmand the control strategy, further optimize the space truss structure of the control scheme, thecontrol effect is good.(5) Application of vibration control in engineering as the background, design andproduction of 1 2 span 3 storey space truss model structure, research and development of 1new shape memory alloy wire control device and the electric heating power system, and itsintegration in the space truss structure model, choose 3 kinds of seismic waves and 3EL-Centro different acceleration peak value, the use of passive and active / passive hybridcontrol method, are not installed, installation, installation of stochastic optimization of shapememory alloy control system under 36 different conditions of space truss structure modelshaking table test, at the same time the corresponding finite element simulation analysis, thetest control system development and the proposed control method is effective and applicable.The results show that, under normal circumstances, the use of shape memory alloy passivecontrol system, earthquake acceleration response of the model structure can be reduced bymore than 20%, the interlayer displacement can be reduced about 30%; the use of shapememory alloy active / passive control, seismic acceleration response of the model structurecan be reduced by more than 30%, the interlayer displacement can be reduced about 45%,show that the proposed control method is better, and it has good application value.