Study On Seismic Behavior Of Prestressed Assembly Frame Joints With Additional Angle Steel

Assembled concrete frame structure has the characteristics of short construction period,stable quality,flexible space arrangement,energy saving and environmental protection,etc.It meets the requirements of green building and civilized construction in China,and is a new type of structure vigorously promoted by the state.In the earthquake,the unreliable connection of the beam-column joints is the main factor leading to the unsatisfactory seismic performance of assembled concrete frame structure.It is of great practical significance for the future development and application of this kind of structure to develop more secure and stable fabricated concrete frame joints with good seismic performance,which is also a hot spot in the research of prefabricated assembly technology.In this paper,the ABAQUS software is used to simulate the seismic behavior of joints in existing prestressed concrete frames with additional angle steel.On this basis,the seismic performance of joints and side joints in the additional angle steel pre-stressed assembly frame and its influencing factors are analyzed by using ABAQUS software.The specific research contents and conclusions are as follows:(1)The research status of assembled concrete frame joints at home and abroad is summarized and analyzed.The seismic mechanism of reinforced concrete frame joints is systematically expounded.The seismic behavior of the additional angle steel prestressed assembly frame joints studied in this paper is introduced in detail.(2)ABAQUS software is used to simulate the joints in the additional angle steel pre-stressed assembly frame,and the simulation results are compared with the test results.It is found that within the allowable range of errors,the two agree well,which verifies the reliability of the finite element analysis method adopted in this paper.(3)Using ABAQUS software to compare and analyze the seismic performance of joints and side joints in the additional angle steel pre-stressed assembly frame and the corresponding joints and side joints in the cast-in-place frame.The results show that the joints and side joints in the additional angle steel pre-stressed assembly frame have good seismic performance and self-recovery ability.(4)Using ABAQUS software to analyze the parameters of joints and side joints in the additional angle steel pre-stressed assembly frame.The results show that increasing the axial compression ratio,effective prestress and concrete strength grade in a certainrange is beneficial to improve the bearing capacity of the joint,while the increase of the ratio of ordinary longitudinal reinforcement in beams and the ratio of ordinary longitudinal reinforcement in columns has no obvious effect on the bearing capacity of the joints.