Research On Shearing Capacity Of Corrugated PBL Shear Connectors In Steel-concrete Composite Bridges

Steel-concrete composite bridge is an important branch in the bridge engineering.Compared with other types of bridges,steel-concrete composite bridge shows apparently a better choice for giving full play to the role of steel and concrete in bearing the stress of bridge structure.Meanwhile,the combination of concrete and steel makes up for the deficiencies of these two materials with the concrete arranged in the compression zone to avoid cracks from tension and steel beam restrained by concrete to avoid the unstable failure due to the yield deformation.These two kinds of materials should be connected together to bear the load.Therefore,the design of connectors is particularly important as the connectors are the key components that connecting the concrete slab and steel beam.In this paper,the structure of PBL connector was improved,and a corrugated PBL connector was proposed with the influencing factors studied.In this paper,the influence of three factors on the bearing capacity of corrugated PBL connector is analyzed by the finite element software-ABAQUS,including the aperture,wave height and through rebar diameter of the corrugated PBL connector.The result shows that regions with larger stress distribution of the PBL connector are located around holes and welding with I-beam.The stress of the holes around gradually decreases from the loading position.The obvious difference was observed between the stress distribution of corrugated PBL connector and plate PBL connector.The stress of folding part of corrugated PBL connector becomes larger,and stress distribution of plate PBL connector is uniform between the apertures.The bearing capacity of corrugated PBL connectors is increasing with the aperture,wave height and through rebar diameter increasing,and the wave height should be compatible with the aperture.Next,the dimensions of the plate PBL connector and corrugated PBL connector was determined according to the calculation results of the finite element software.Launch test was conducted on plate PBL connector and corrugated PBL connector specimen(include total 6 specimen)through to draw the loading-displacement curve of specimen.It could be seen from the failure form and loading-displacement curve that the whole loading process of the specimen is divided into three stages.The first stage is the elastic stage,greater rigidity,and the displacement of steel parts is very small,the concrete slab has no cracks at this stage.The second stage is the plastic stage,at this time,the concrete slab cracks began to appear,and to carry out to up,due to the appearance of the crack,the rigidity is decreasing.The third stages is the yield stage,the cracks reach the concrete top,and carry out to the PBL connector,the rigidity of the specimen is smaller,the curve has become smooth,displacement is larger,and more discrete.The test results demonstrate that the bearing capacity of corrugated PBL connectors was larger than the bearing capacity of plate PBL connectors,and increased by about 45.18%.The results of numerical simulation and experiments showed that the bearing capacity of the corrugated PBL connector was obviously larger than the bearing of plate PBL connectors and the feasibility of the proposed of corrugated PBL connector structure.