Study On Seismic Performance Of Joints Of Prestressed Hybrid Assembled Concrete Frame

Assembly connection has the advantages of high construction speed and high engineering quality,but its application and promotion are restricted by the problems of low bearing capacity,poor energy consumption,insufficient ductility and small overall stiffness.In this paper,based on the existing research results of assembly joints at home and abroad,the following research is carried out:(1)Based on the optimization of prestressed direct assembly,a new type of prestressed hybrid connection of beam and column is designed.The upper and lower columns are connected by sleeve grouting.The bearing capacity of the joint is checked according to the formula.(2)In this paper,the finite element simulation is carried out for the prestressed composite assembled concrete frame joint,the cast-in-place concrete frame joint and the prestressed direct assembled concrete frame joint.The seismic performance of each joint is compared from hysteretic curve,skeleton curve,ductility,energy dissipation performance and stiffness.(3)The influence of three design parameters,namely,concrete strength,energy dissipation angle steel strength and thickness,on the seismic performance of prestressed hybrid fabricated frame joints is studied.(4)By using the pushover analysis module of SAP2000,the overall seismic performance of the prestressed hybrid assembled concrete joint frame is analyzed to verify that the overall frame meets the seismic code requirements.The main conclusions are as follows:(1)The prestressed composite assembled concrete frame joint has a full hysteretic curve;its seismic performance is greatly improved compared with the direct assembled joint,in which the energy consumption capacity is increased by 154.29%;the energy consumption capacity and ductility are better than the cast-in-place joint level,which are increased by 33.4% and 44.25% respectively,and the bearing capacity can reach the castin-place level,and the stiffness is slightly weaker than the cast-in-place joint.(2)For the prestressed composite fabricated concrete frame joints,increasing the strength of precast beam concrete can improve the seismic performance,increasing the strength of energy consuming angle steel has no obvious effect on the seismic performance,and increasing the thickness of energy consuming angle steel can significantly improve the seismic performance.(3)In the case of frequent earthquake and rare earthquake,the peak displacement and inter story displacement angle of three span six story frame with prestressed composite assembled concrete joint under uniform load and inverted triangle load meet the seismic code requirements.