Seismic Performance Of Damage-Control Fuses And Fuse-equipped Structures

With the development of urbanization,a large number of casualty and social wealth are enriched in cities.One city will be faced with risks of seismic disasters,when a destructive earthquake occurs near it.The seismic safety and resilience of important buildings are significant for urban seismic prevention and disaster mitigation.Therefore,it is necessary to develop damage-control and function recoverable techniques for important structures after earthquakes.In this paper,the seismic damage-control fuse(hereafter:fuse)was taken as research object.The mechanical behavior of the fuse and the seismic performance of the fuse-equipped elements and structures were investigated by test,theoretical analysis and finite element simulation.The main work and conclusions are as follows:(1)The innovative damage-control fuses with flat type or special pre-bending configuration were proposed.The mechanical behavior of proposed fuses under cyclic loading was investigated by component testing and theoretical analysis.The effect of key parameters including slenderness ratios,pre-bending types and heights,on strength degradation,stiffness and axial deformation was analyzed.A mechanical model was proposed based on modified Gomes-Appleton model.(2)The damage-control and mechanical mechanism of steel beam-to-column joints with pre-bending fuses were studied.A test program,including two joints with out-plane pre-bending fuses and another two with in-plane pre-bending fuse,were carried out.The reasonable strength threshold was suggested by finite element parameter analysis.A mechanical model of fuse-equipped joints was proposed under analyzing on mechanical and deformed mechanism.(3)The influence of reinforced concrete slab on mechanical behavior of fuse-equipped joints was revealed from element level.A research program,including four specimens of fuse-equipped joints with slab and pre-bending fuses,was carried out by full-scale quasi-static test and finite element parameter analysis.The hysteretic behavior,strength degradation,damage-control and seismic performance were investigated.The design recommendation of reinforced concrete slab was suggested.(4)A hysteretic model of the fuse-spanned section was proposed for elasto-plastic analysis of fuse-equipped structures,and the influence of fuses on the damage-control of steel frame was revealed from structural level.A numerical model of fuse-equipped elements is proposed and verified,based on the configuration and working mechanism of the pre-bending fuses.The damage mechanism,deformation and failure mode of the innovative steel frame with fuses were studied by static and dynamic elasto-plastic time history analysis.The influence of different types of fuses,different strength thresholds and material strength of main component on damage-control was revealed.(5)The influences of fuses on the seismic damage-control of high-rise hybrid structures were revealed from structural level.The effect of fuses on the seismic response and damage-control of beam-wall joints was investigated by shaking table test of 1:10 large-scale high-rise hybrid structure with fuses.The protectiveness and designed rationality of fuses are verified.The research provides a basis for the design and application of seismic damage-control fuse and a reference for improving the damage-control performance and functional restoration of structures.