Study On Shear Bearing Performance Of Assembled Perforated Steel Plate Connectors

With the rapid development of fabricated steel-concrete composite structures and efficient construction technology,shear connectors between steel and concrete structures have attracted the attention of scholars at home and abroad.The perforated steel plate shear connector,which is widely used in traditional steel-concrete composite structures,has the advantages of high bearing capacity and good fatigue resistance.However,due to its mismatch with the current prefabricated construction technology,its application in prefabricated steelconcrete composite structures lags behind.Therefore,on the basis of ensuring the excellent shear resistance of traditional perforated steel plate connector,a new type of steel-rubber mortise-and-groove perforated steel plate connector(steel-rubber mortise-and-groove perforated steel plate connector)is put forward by adding steel ring and rubber ring between penetrating steel bar and perforated steel plate,and changing the hole of perforated steel plate into open groove shape,so as to popularize the application of this type of connector in assembled composite structure.In order to analyze the mechanical performance of the new fabricated perforated steel plate shear connection,the main research work and achievements in this paper are as follows:(1)Three groups of 9 push-out specimens were made,including: fabricated concrete mortise-shaped steel plate connectors without steel ring and rubber ring(concrete mortiseshaped steel plate connectors),fabricated steel ring mortise-shaped steel plate connectors with steel ring tenon and rubber ring thickness(steel ring mortise-shaped steel plate connectors)and fabricated steel-rubber mortise-shaped steel plate connectors with steel ring and rubber ring thickness(steel-rubber mortise-shaped steel plate connectors with steel ring and rubber ring thickness(steel-rubber mortise-shaped steel plate connectors).The failure mode,loadslip curve and stress variation of key components are analyzed by push-out test.The results of push-out test show that the shear stiffness,shear bearing capacity and slip of steel ring tenonperforated steel plate connector are greatly improved due to the setting of steel ring compared with concrete tenon-perforated steel plate connector;Because of the steel ring and rubber ring,the shear stiffness of steel-rubber tenon-perforated steel plate connector is weakened,and the shear bearing capacity and slip are greatly improved.(2)A refined nonlinear finite element model is established,and the accuracy of the calculation results of the model is verified according to the deduction test.The finite element simulation method is used to analyze the sensitivity parameters of steel-rubber tenon perforated steel plate connector,and the effects of steel ring thickness,rubber ring thickness,through steel bar diameter,concrete strength and perforated steel plate strength on the shear performance of connector are studied.The results show that with the increase of slip,the shear force transmitted by concrete tenon in each specimen decreases continuously,while the shear force transmitted by through steel bar and steel ring tenon increases continuously.In addition,increasing the thickness of steel ring,the diameter of penetrating steel bar,the strength of concrete and the strength of perforated steel plate will improve the shear performance of connectors,among which the strength of perforated steel plate has the greatest improvement on the shear performance of connectors;Increasing the thickness of the rubber ring will significantly increase the slip of the connector,improve the shear deformation ability of the connector,and weaken the shear stiffness and shear bearing capacity of the connector.(3)Based on the existing calculation methods of shear performance of steel plateconnectors with openings at home and abroad,combined with the results of finite element parametric analysis and considering the stress balance of the extruded specimens,the calculation methods of shear bearing capacity and shear stiffness of connectors are put forward.By comparing with the extruded test and finite element simulation results,it is found that the predicted results of this calculation formula have a high degree of coincidence.The research results of this paper can provide important theoretical basis and reference significance for the further research and popularization of steel-rubber tenon-perforated steel plate connectors.