Design And Performance Study Of A Negative Stiffness Intelligent Impact Isolation Bearing

Seismic isolation and shock absorption control of building structure and anti explosion of building structure are an important part of the seismic resistance of building structure.Different from the use of traditional isolation bearing,the design of isolation device can actively change its mechanical characteristics to adapt to different loads.In view of the defects of the traditional isolation bearing,such as low isolation effect,poor adaptability,and unable to resist the impact load,this paper aims to solve the practical engineering problems,and develops a negative stiffness intelligent impact isolation bearing,which can make the structure meet the requirements of seismic fortification when encountering frequent earthquake or rare earthquake,and has a certain impact load resistance.In this paper,the dynamic mechanical properties of the negative stiffness intelligent impact isolation bearing are tested,and the corresponding dynamic mechanical model is established,and its parameters are identified.Finally,the active control simulation of the specific structure is carried out with this model.The main contents of this paper include:1.The theoretical study of the negative stiffness intelligent impact isolation bearing.This paper analyzes the basic isolation principle of the negative stiffness intelligent isolation bearing,analyzes the horizontal stiffness of the rubber isolation layer,the rubber limit layer and the magnetorheological elastomer layer in the negative stiffness intelligent isolation bearing,analyzes the generating mechanism of the negative stiffness of the negative stiffness platform and the lateral negative stiffness provided,establishes the theoretical formula of the output of the negative stiffness intelligent impact isolation bearing,and determines the output based on this The structural dimensions of rubber isolation layer,rubber limit layer,magnetorheological elastomer layer and negative stiffness platform are analyzed,and the basic theory of magnetic circuit is analyzed.2.Preparation and performance test of MR elastomer.The magnetorheological(MR)elastomer suitable for the negative stiffness intelligent shock isolation bearing was prepared by selecting the appropriate matrix.The shear storage modulus and loss factor of the MR elastomer under different strain and magnetic field strength were analyzed by experiments.3.The design and development of the negative stiffness intelligent impact isolation bearing.A kind of negative stiffness intelligent impact isolation bearing is designed and developed for different isolation targets.The finite element software ABAQUS is used to simulate and analyze the overall output of the designed isolation bearing,and ANSYS is used to simulate the magnetic field of the designed isolation bearing.The magnetic resistance of each part is calculated,and a full-scale negative stiffness intelligent impact isolation bearing is manufactured.4.Performance test and mechanical model of negative stiffness intelligent impact isolation bearing.The mechanical properties of the developed isolation bearing under different displacement and frequency conditions are tested,and the hysteretic curve and mechanical properties under different conditions of the negative stiffness intelligent impact isolation bearing are analyzed.The parametric representation of the dynamic mechanical model of the isolation bearing is written,and the parameters are identified by MATLAB software.5.The simulation of vibration control of building structure based on negative stiffness intelligent impact isolation bearing.Aiming at the simplified building structure,based on the dynamic mechanical model of the negative stiffness intelligent impact isolation bearing,the vibration control simulation of the building structure based on the negative stiffness intelligent impact isolation bearing is carried out.The results show that under different frequency spectrum and different intensity of earthquake,the displacement and acceleration response of the structure can be reduced more effectively than that of the non isolation and the traditional isolation.