Research On PBL Shear Connector For Steel-concrete Composite Segment Of Hybrid Girder Cable-stayed Bridge

As the spans of modern bridges tend to be longer and longer, the hybrid girdercable-stayed bridge has become a very important bridge type. The steel-concretecomposite segment of hybrid girder, where there is a mutation on sectional and materialcharacteristic, is the weak point of the whole structure and gains extensive attention. To agreat extent, the performance of the steel-concrete composite segment depends on theshear connector’s design rationality. At present, the most widely used shear connector istraditional shear connector represented as stud in construction practice. However, in theview of the current development tendency, perfobond rib shear connector, that is PBLshear connector, has the best application prospect.PBL shear connector is one kind of the rigid shear connectors, which transfer shearforce through the synergy between concrete tenon in the hole of steel plate andthrough-rebar. Compared with stud, PBL shear connector has higher shear stiffness,greater bearing capacity and better ductility, and its production process is easier. Atpresent, there are little research on PBL shear connector at home and abroad, and as aresult, the recognition of this field is still at primary stage. In recent years, along withhybrid girder cable-stayed bridges’ rapid development and widespread use, research onPBL shear connector attracts more and more attention.Relying on some hybrid girder cable-stayed bridge, this thesis has studied the internalforce and failure mechanism of PBL shear connector of steel-concrete composite segmentunder load effect through finite element non-linear simulative analysis. And a parametricanalysis on influence factors of PBL shear connector’s bearing capacity has been given.Through the study of the finite element analysis results, conclusions as follows can be got:the failure mechanism of PBL shear connector is closely related to concrete; concreteplays a leading role in the linear elastic stage of PBL shear connector; steel bar, whichdetermines PBL shear connector’s ultimate bearing capacity, is the main member forbearing loads in the stage of plastic deformation. Through the parameterization, it can beconcluded that concrete strength, diametre of through-rebar and constructional reinforcement ratio are all have an effect on PBL shear connector’s ultimate bearingcapacity at different degree.