Research On The Seismic Performance Of Precast Reinforced Concrete Beam-column Connection With Frictional Artificial Plastic Hinge

Precast concrete structures can offer several advantages such as environmental friendliness,high material utilization,construction efficiency,and guaranteed quality.Nevertheless,the precast concrete connections are not integrally poured,resulting in the poor seismic behavior of the prefabricated structure.In order to ameliorate the integrity and connection performance of the prefabricated structures,researchers have proposed many solutions.The replaceable energy-dissipating element is one of the implementation methods of the recoverable functional structure.In the recoverable functional structures,the structural function can be easily restore by replacing the damaged energy-dissipating elements after the earthquake.However,the currently proposed replaceable energy dissipation connections exist problems such as complex configuration and imperfect performance.In this paper,a replaceable Frictional Artificial Plastic Hinge(FAPH)was proposed to connect the prefabricated concrete members.To investigate the seismic performance of FAPH,the experiment of a precast beam-column connection with FAPH and a cast-in-situ beam-column connection was carried out.Moreover,the finite element model(FEM)was calibrated and employed to perform parametric analyses,and the theoretical analysis was conducted based on the experimental research and numerical analysis.Finally,the FAPH device was optimized and its bearing capacity calculation formulas were proposed.The main research works of this paper are as follows:(1)In this paper,a prefabricated concrete beam-column connection with FAPH and a cast-in-situ concrete beam-column connection were manufactured in this paper.The failure mode of specimens and the seismic performance in terms of hysteresis performance,bearing capacity and deformation capacity,energy dissipation capacity and strain distribution were studied and recorded.The test results show that the beam-column connection with FAPH has higher ultimate bearing capacity,energy dissipation capacity and ductility compared with cast-in-place concrete beam-column connection.(2)The ABAQUS finite element software was utilized to simulate the FAPH beam-column connection.The stress cloud diagram and hysteresis curve of the numerical simulation were compared with the experimental results.On the basis of verified numerical model,the further parameter analysis of the FAPH beam-column connection was carried out.The parameters include axial compression ratio,friction coefficient,bolt preload of pin and initial clearance between lug-hole and pin.The friction coefficient and bolt preload of pin have significant influence on the seismic performance of the beam-column connection with FAPH.(3)Based on the experimental and numerical analysis,the frictional artificial plastic hinge was optimized to further improve the bearing capacity and energy dissipation capacity of it.And the seismic performance of precast beam-column connection with optimized FAPH was studied by ABAQUS.Subsequently,based on the working mechanism of the FAPH device,referring to the specifications and mechanical formulas,the calculation formulas of the bending and shear bearing capacity of the frictional energy-consuming artificial plastic hinge device were given.