Extruded Magnetic Shape Memory Alloy Dampers Mechanical Properties And Vibration Damping Design Method

Magnetic Shape Memory Alloy(MSMA),as a new type of intelligent material,has the same shape memory effect and super elasticity effect as the traditional temperature-controlled shape memory alloy.The main work and results of this paper are as follows:(1)Establishing a segmental linearized hyperelastic intrinsic model of MSMA.Based on the framework of classical plasticity theory,a segmental linearized intrinsic model is established to describe the MSMA hyperelasticity effect under different magnetic fields by introducing the volume fraction of martensite with stress selective orientation as an internal variable;combined with the experimental data in the literature,a logistic relationship function is proposed to describe the relationship between the critical stress of martensite reorientation and inverse reorientation and the magnetic field;using the established MSMA segmental linearized intrinsic model The MSMA hyperelasticity effect is simulated numerically,and the results are in good agreement with the experimental data in the literature.(2)Design the extruded MSMA damper.The mechanical calculation model of the extruded MSMA damper is derived by combining the force analysis of the extruded MSMA damper with the MSMA segmental linearized hyperelasticity intrinsic model;the finite element model of the damper is established with the help of ABAQUS software to verify the correctness of the mechanical calculation model;on the basis of the mechanical calculation model of the damper,the effects of the ambient magnetic field strength,the length and cross-sectional dimensions of the MSMA bar,the number of MSMA basic units,the contact surface friction coefficient and the height of the triangular slider section on the mechanical performance of the damper are analyzed.The effects of ambient magnetic field strength,length and cross-sectional dimensions of MSMA bars,number of MSMA basic units,contact surface friction coefficient and height of triangular slider cross-section on the mechanical properties of the damper were analyzed.(3)Analysis of vibration damping performance of extruded MSMA dampers.Propose a performance-based design method for extruded MSMA dampers;build a material ontology that can simulate extruded MSMA dampers in the Open Sees software platform.Based on the practice of viscous energy dissipation damping design for multi-story school buildings,the design of extruded MSMA dampers for multi-story school buildings was carried out,and the effects of the two damping design methods on structural performance were investigated under different characteristics of ground shaking(near-fault pulsed ground shaking,near-fault non-pulsed ground shaking and far-field shaking).The results show that compared with the viscous energy dissipation damping technology,the extruded MSMA damper damping design can more effectively improve the seismic performance and recoverable performance of the structure.