Research On Seismic Performance Of Fabricated Concrete Structures Based On Beam End Hinge And Y-Shaped Eccentric Bracing

The concrete beams and columns in prefabricated concrete structures are prefabricated in the factory and dryly connected and assembled on site.This structural form combines the advantages of green concept and building industrialization,but under rare earthquake action,its lateral stiffness and seismic performance are low,which is not conducive to its use in high-rise buildings.The Y-shaped eccentric support structure has good lateral stiffness,energy dissipation ability,and recoverable performance,and can dissipate seismic energy through plastic deformation of the energy dissipation section.Introducing Y-shaped eccentric braces in prefabricated concrete structures can effectively improve their lateral stiffness,seismic performance,and post earthquake functional recovery ability.However,the bending deformation of concrete beams and columns under rare earthquakes can lead to additional opening and closing effects at the supporting frame nodes,and the connection nodes between the energy dissipation section and the frame beam will also fail prematurely,resulting in insufficient energy dissipation of the energy dissipation section.Therefore,this article proposes a prefabricated concrete structure based on embedded steel and Y-shaped eccentric support,and conducts research on prefabricated concrete hinge beams and prefabricated concrete beam energy dissipation segment composite nodes based on bending shear separation,respectively,to clarify the corresponding failure modes,ultimate bearing capacity,strain analysis,and other research.The main research work is as follows:(1)Read relevant literature and address the issues of opening and closing effects and premature failure of frame beam and energy dissipation section nodes when introducing eccentric support in prefabricated concrete structures.Research is conducted on a type of prefabricated concrete articulated beam and energy dissipation section frame beam composite node based on bending shear separation,and the research content and technical roadmap of this article are introduced.(2)To weaken the adverse effects of the opening and closing effects between prefabricated beams and columns and supports,a prefabricated concrete articulated beam based on embedded steel is proposed based on flexible connection method.Design and manufacture hinged beam specimens with embedded channel steel and angle steel,and conduct bending performance tests to analyze their load-deflection curves,strain analysis,bearing capacity,and other performance.Based on experiments,finite element software is used for fitting correction and parameterization analysis.(3)In response to the problem of excessive damage to the connection nodes between frame beams and energy dissipation sections under rare earthquakes,the length,cross-sectional area,and post earthquake recovery performance of pre embedded shear keys are considered in the design and production of components for bending shear separation composite joints,and seismic performance tests are conducted.Study the failure mode,hysteresis performance,stiffness degradation,energy dissipation capacity,and strain distribution of bending shear separated composite joints.(4)In order to study the application of the above bending shear separated composite nodes and hinged beams in Y-shaped eccentrically braced frames,two related frame structural models were constructed using finite element software,using rigid beam connections and hinged beam connections,respectively.Perform cyclic loading on two frame models under frequent,fortified,and rare earthquakes,and compare the final concrete damage,stress magnitude,and hysteresis curve performance of the two frame models.