Research On Seismic Performance Of Fabricated Concrete Frame With Energy Dissipation Connector

Fabricated concrete structure is widely researched and applied in practical engineering in recent decades,as it is in accordance with the development trend of the building industrialization in China.The connection between the beam and the column in a frame is the key factor on the mechanical property of the whole building.Assembling the ductile connectors in the fabricated concrete frame has been a dominant trend,which is widely researched in the performance-based seismic design method.Assembling the ductile connectors in the beamcolumn joint of the fabricated concrete frame could help control the damage mechanism of the structure,which could concentrate the damage of the structure into the ductile connectors and prevent the main structural members from damage.In this thesis,a kind of slippage-free energy dissipation connector(SFDC)is proposed,which is assembled in the beam-column joint of the concrete frame and used as ductile connectors.The SFDC is composed of energy dissipation steel bars and adjustable composite rebar connectors,which could prevent the SFDC from slippage in the beam-column joint.The experimental study and finite element analysis on the mechanism of the SFDC and SFDC-reinforcement concrete frame(SFDC-RCF)is conducted.The main contents of the thesis are listed as below:(1)The common constructions and the problems of the existed fabricated concrete frame is summarized.The mechanical properties of the beam-column joint in the precast concrete frame with Dywidag ductile connectors(DPCF)is analyzed.The concept of the SFDC-RCF is proposed.(2)Low-cycle reversed loading tests on the SFDC is conducted.The mechanical properties,hysteretic performance,axial stiffness and energy dissipation capacity are analyzed,respectively.(3)Low-cycle reversed loading test on the SFDC-RCF is conducted.The damage and fracture mode are observed.The mechanical properties such as the skeleton curves,energy dissipation capacity,ductility,etc.are analyzed,respectively.The seismic performance of the SFDC-RCF is studied.(4)It is found in the test that the clearance at the beam-column joint surface of SFDC-RCF increases with the increase of loading displacement.This thesis analyzes this phenomenon in detail.The mechanism of gradually increasing gap is revealed.The inevitability of this phenomenon in ductile joints containing energy-dissipating steel bars is also confirmed.The measure for improving the SFDC-RCF is also proposed.(5)The finite element analysis on the SFDC-FCF is conducted by OpenSees.The loading protocol of the model is same as that in the experiment.The simulation results are compared with the test results.The reliability of SFDC-RCF joint is verified.Finally,the parameters that affect the performance of the joints are selected for parameter analysis.