Research On Seismic Performance Of New Multi-stage Energy-dissipating Self-centering Steel Structure Joint

Aiming at the problem of large residual deformation and difficult repair after the earthquake of traditional structures,Academician Lu Xilin of Tongji University has put forward the anti-seismic design concept of "recoverable functional city",to design a structure that does not damage or only quickly repairs damage during an earthquake.Based on this design concept,this paper proposes a new hidden staged energy dissipation damper and a self-resetting steel frame joint based on the damper.The purpose is to use the energy dissipation damper to control the seismic response of the structure,reduce the residual deformation of the structure through the self-reset device,and provide new ideas for the earthquake resistance of the middle and high-rise buildings.The main research work and conclusions of this article are as follows:(1)This paper proposes a new hidden staged energy dissipation damper and a self-resetting steel frame node based on the damper,and applies for related patents.(2)The finite element simulation was used to study the energy dissipation performance of the damper,and it was proved that it has a staged energy dissipation effect and good energy dissipation capability.(3)Sort out and derive the seismic design methods and formulas of self-resetting steel frame structures,and use the formulas to explain the amount of slip at the nodes of self-resetting structures and the conditions under which resetting occurs.(4)ABAQUS was used to establish a new type of energy-consuming self-resetting steel structure node model and ordinary steel structure node model,and analyze the mechanical properties of the hysteretic curve,skeleton curve,stiffness degradation curve and energy consumption coefficient curve of the two types of nodes.The conclusion shows that the new energy dissipation node proposed in this paper has the ability to improve the residual deformation of the structure,increase the structural rigidity and bearing capacity.(5)The influence of the initial prestress size,the number of prestressed steel bars,the energy dissipation soft steel damper material and the position of resetting ribs on the seismic performance of the joint specimen are analyzed.The conclusion shows that the larger the prestress value and the more prestressed steel bars,the greater the bearing capacity of the node,and the better the self-reset effect;the material of the soft steel damper will affect the energy consumption stage and energy dissipation capacity of the node The stress bars are still self-resetting on the neutral surface of the beam,and can save space and prevent the beam flange from buckling instability.