Reserch On Seismic Performance Of New Type Crimping Pec Column-steel Beam Composite Frame With Partial Self-centering Brs Energy-dissipating Connection

By adding PT strsnds and energy dissipating(ED)device to the main components,the self-centering structure can achieve self-centering,significantly reduce residual drift,alleviate structural damage process,and have good energy-dissipating capacity after the earthquake.However,the existing self-centering structure requires that the main components of the structure be in an elastic state,which will inevitably lead to excessive safety redundancy and high construction cost,thus limiting its application scope.In order to better achieve unification and harmonization in self-centering function,energy-dissipation and the safety redundancy of structure,the research group proposed the design idea of partial selfcentering connection with certain length PT strsnds and energy-dissipating device in the structure node area based on the existing concept of self-centering connection.Based on the research of the self-centering idea and the existing research results,in order to systematically study the seismic performance of new type crimping PEC column-steel beam composite frame with partial self-centering BRS energy-dissipating connection,a two –storey new type crimping PEC column-steel beam composite frame specimen with partial self-centering BRS energy-dissipating connection was taken as the research object.This paper tested the mechanical behavior of the specimen under the lateral cyclic loading,used the finite element software ABAQUS to completed validation,and consider layout of penetrating bolts,BRS plate hole size,axial force,column feet connection mode of 4 design parameters in finite element analysis to comprehensively study the influence law of the hysteretic behavior,lateral stiffness,energy-dissipation capacity,self-centering function and other seismic performance of the composite frame.Research results show that the set of the bolts and PT strsnds can improve the initial lateral stiffness of the specimen.Until the end of the loading,the bearing capacity of test specimen did not decline,the residual drift of the whole part,first layer and second layer of the specimen does not exceed 0.5% when interstory drift reaches the limit of 2% of frame structure at design basis earthquake level and the energy-dissipation capacity of the specimen increases significantly with the main components entering yielding,which indicates that the structure has good bearing capacity,self-centering function and energy-dissipation capacity.The overall force law of the test specimen is basically consistent with that of the simulated specimen,so the simulation is feasible.The specimen with the single-side arrangement of the bolt fails to achieve the predetermined design idea and the steel beam does not enter the pressure-bearing force state,while the bilateral arrangement of the bolts effectively realizes the predetermined design idea,before the joint angle reaches 2×10-2rad,the main components of the structure are basically in the elastic state,and the structure almost achieves completely self-centering.When the joint angle reaches 2×10-2rad,the specimen enters the pressure-bearing mode,the bearing capacity and energy-dissipation capacity are obviously improved,the lateral stiffness degradation speed is slowed down,and the selfcentering function is weaker than the specimen with single-sided arrangement of the bolts.Increasing the size of the front hole of the BRS plate makes the specimen enter the pressurebearing type mode later,so that the bearing capacity is reduced,and the mitigation effect on stiffness degradation is also small,but the self-centering function is better,and the energydissipation capacity is slightly reduced.Whether the axial force is applied to the top of the column has little effect on the seismic performance of the specimen.The fixed connection form of the column foot obviously enhances the lateral stiffness and bearing capacity of the structure.The development process of plasticity of the specimen is faster,the energydissipation capacity is obviously improved,and the self-centering function is weak.Through the analysis of the research results,it is suggested that the size of the long round hole of BRS connector can be reasonably selected according to the different design objectives,so that the structure can meet the corresponding requirements,and the organic unity of the structure's self-centering function,energy-dissipation capacity and safety redundancy can be achieved.