Optimization Analysis Of Seismic Response Of Space Truss Structures Based On SMA Damper

With the development of the national economy,there have many characteristics of the space structure of the building,and the spatial structure of the seismic and vibration requirements are higher.Only relying on the structure itself is difficult to resist the external earthquake.Usually the structure need to add shock absorber system Reduce the vibration response of them.In recent years,the application of intelligent materials and the development of vibration control theory have provided a new way for structural vibration control.In this paper,a vibration control system of space rod structure based on shape memory alloy is proposed by using the superelasticity of shape memory alloy.The shaking system is optimized by shark algorithm and simulated by shaking table.The main contents of the paper are:(1)The mechanical performance test of 12 groups of 48 austenitic shape memory alloys was carried out by using computer servo control material testing machine.Through changing the main test parameters such as loading amplitude,loading rate,cycle number and diameter,we studied the mechanical properties of shape memory alloy.The results show that the loading amplitude and loading rate are the main parameters that affect the mechanical properties of austenitic materials.At the same time,based on the shape memory alloy property test we established the rate related constitutive model of the shape memory alloys.(2)Based on the artificial fish swarm algorithm,the SMA constitutive model described in this paper is used to optimize the position and quantity of SMA wire in a space bar structure.Through the MATLAB language to analyse the seismic response and study the effect of the damping control before and after the optimization of the space bar structure.The results shows that utilizing the artificial fish swarm algorithm tooptimize the SMA damping system,the global convergence efficiency is high and the robustness is strong.After optimization,the displacement of the space rod structure under earthquake excitation is reduced by 54.85%.The effect is obvious.(3)A 2-span 3-layer spatial structure model was designed and fabricated,and the SMA damping system was integrated into the spatial model structure.Four kinds of arrangement schemes were arranged without arrangement,random arrangement,genetic optimization and artificial fish swarm optimization,and the model of the space bar model simulated seismic shaking table test.The results show that the average displacement of the interlayer displacement can be reduced by 35.4% and the acceleration can be reduced by 23.5% on average when the genetic algorithm is used to optimize the control effect.However,the control scheme is optimized by the fish swarm algorithm.Among them the interlayer displacement can be reduced by 41.7%,the acceleration can be reduced by 29.7% on average level.The results show that the SMA damping control system proposed in this paper can effectively reduce the seismic response of the space bar structure.The optimization method of artificial fish swarm optimization has obvious effact,and the optimization effect of interlayer displacement and acceleration is improved by 17.9% and 26.4%.The proposed SMA damping control system and optimization method is effective and feasible for further research and application of reference.