Experimental Study On Seismic Performance Of Precast Reinforced Concrete Socket Type Beam And Column Joints

With the great support to the development of prefabricated structure in our country,the prefabricated structure has a broad development prospect.Based on the research status at home and abroad,and on the basis of the previous research group,this paper innovatively designed a new type of precast reinforced concrete steel sleeve joint,and carried out theoretical and experimental research on the seismic performance index of steel sleeve connection beam-column joint.The main work of this paper and the conclusions are as follows:(1)Read the literature and research results of prefabricated beam-column joints,frame joints and steel sleeve joint at home and abroad,and describe in detail the structural form,size,reinforcement,advantages and installation process and process of the sleeve joint designed in this paper.In this paper,the main purpose of the test and the main data content recorded and measured in the process of the test are introduced in detail,and the production of joint specimens,the test scheme,the loading device and the content of the measurement are described in detail;(2)this paper design a common node and five prefabricated reinforced concrete cast-in-situ socket type beam-column node and T test,extract the node of the hysteresis curves,skeleton curves,strength degradation and stifness degradation,ductility,energy dissipation and strain changes,the shear bearing capacity of the shear deformation,residual deformation and force of prestressed steel as a result,Through the analysis of the longitudinal reinforcement of the beam,the thickness of the stiffening rib,the prestress and whether the column steel sleeve has side plate or not,and the comparison with the ordinary cast-in-place specimens,the results show that the socked joints have high bearing capacity,good ductility,strong deformation resistance and excellent deformation recovery ability.In addition,the ability of the new joints to resist shear failure in the energy dissipation and the core area of the joints is almost equal to that of the cast-in-place joints.The nodes studied in this paper are innovated and improved on the design idea of ordinary steel sleeve,such as the improvement of the connection mode of the nodes,and the use of high-strength bolts to j oin the nodes makes the connection more reliable,and it is also more convenient for disassembly and replacement in the future.In addition,the application of prestress in the normal section of the beam also makes the joints have better overall performance,can better resist the earthquake damage;(3)The finite element software ABAQUS was used to carry out numerical simulation analysis on precast assembled steel sleeve connected reinforced concrete joint specimens.The simulation results were compared with the test results,and the following conclusions were drawn:on the one hand,the failure location of the finite element simulation was basically consistent with the test results;On the other hand,the skeleton curve obtained from the test is basically consistent with the results obtained from the finite element analysis,which indicates that the finite element model used in this paper can accurately simulate the loading process of the test.Finally,the extension analysis of the joint parameters is carried out.Through analyzing the influence of different steel plate strength and concrete strength on the bearing capacity of the joint,the results show that the strength of steel plate has less influence on the bearing capacity of the joint,while the strength of concrete has a greater effect on the bearing capacity of the joint.