Experimental Research On The Seismic Profermances Of A Precast Composite Frame With New Steel Plate Energy Dissipation Device

The development of assembled buildings can not only improve the quality and efficiency of constructions,but also reduce labor and achieve energy conservation.In the transformation and upgrading process of the construction industry in China,the research and practice of precast structures have developed rapidly in recent years.However,the precast structures still have problems like complicated joint structure,inconvenient construction and insufficient applicability,which counteract the merits of building industrialization.To address the above problems,this research proposes a precast composite frame structures with new steel plate energy-dissipation device.Through the pseudo-static tests and numerical analysis,the seismic performance of the system is researched.The main work and conclusions are as follows:(1)The current application status of precast concrete frame structure is summarized firstly.Through the literature review,the new frame joint forms of precast structure and metal dampers are classied and summarized.A steel-concrete composite frame structure is proposed,in which metal damper is introduced into the composite frame to form a precast energy-dissipating system.(2)Based on the preliminary experimental results of duplex assembled I-shaped steel panel dampers,an improved shear plate damper which is convenient for modularization is proposed.Cyclic loading test of the new damper is conducted.The experimental results including hysteresis curve,skeleton curve,energy dissipation and failure mode are analyzed to verify the hysteretic performance of the damper.It is showed that the new steel plate damper has the characteristics of large initial stiffness,good ductility and strong energy dissipation ability.(3)The finite element analysis software ABAQUS is used to numerically simulate the damper.And the accuracy of the model is verified by comparing it with the results of the experiment.Parametric analysis of the width-to-height ratio,weakening area and energydissipating element spacing is carried out,and the recommended range of values for the key parameters in the design of the new dampers are proposed.(4)In order to study the seismic performance of the composite frame equipped with damper,a half-scale precast composite frame is designed and fabricated,and the specimen is conducted under pseudo-static test.The experimental results including failure mode,hysteresis curve,skeleton curve,strength,ductility,stiffness degradation and energy dissipation ability are analyzed to evaluate the seismic performance of the frame-damper specimen from multiple perspectives.The results indicate that the position of the plastic hinge of the frame can be accurately controlled by weakening the flange of the beam;the energy dissipation system does not fully exert its ductility due to local connection breakage of the beam span,so reasonable construction measures should be taken to place the damper in the frame.(5)OpenSees is used to conduct numerical analysis of the frame-damper specimen,and the analysis results are compared to the measured results to prove the accuracy of the finite element model.Parametric analysis based on established model is conducted,leading to the following conclusions: setting dampers in the frame can effectively improve the initial stiffness,yield load,bearing and energy dissipation ability of the overall structure;when the beam members connected to the dampers use steel beams,the structural system have the best ductility and energy dissipation capacity.Through the above research work,this research analyzes the seismic performance of a precast composite frame equipped with energy dissipation device from both aspects of component and structure.Some basic experimental data and finite element calculation method are provided,laying the foundation for the further research and application of this structural system.