Shear mechanism of Rubber-Sleeved Stud (RSS) connectors in the steel-concrete interface of cable-pylon composite anchorage

Abstract

The Ordinary Headed Stud (OHS) connector has been widely used in the steel–concrete composite structures. In some cases, the shear stiffness of partial OHS connectors could be beyond the actual demand, resulting in the uneven distribution of connector shear force. Therefore, the authors proposed the Rubber-Sleeved Stud (RSS) connector to reduce the shear stiffness of OHS connectors and enhance the deformation ability of the steel–concrete interface. In order to investigate the shear mechanism of RSS connectors in the steel–concrete interface of cable-pylon composite anchorage, the segmental model test and Finite Element (FE) analysis were carried out. The connector shear force, steel–concrete relative slip and concrete pylon stress under typical RSS connector layouts were discussed. Research results show that the maximum shear force of stud connectors in the actual pylon could be decreased by 20% when RSS connectors are adopted in the steel–concrete interface. RSS connectors possess better deformation ability so that the strain difference between two shank sides of the RSS connector is significantly greater than that of the OHS connector. Furthermore, the shear mechanism of RSS connectors is affected by their layouts in the steel–concrete interface. The peak connector shear force can be respectively reduced by 14.3%, 28.8% and 33.7% when RSS connector ratio λ (i.e. ratio of RSS connector number to total connector number) equals to 0.28, 0.50 and 0.72 compared with λ = 0. The shear force range of stud connectors is simultaneously decreased. When the RSS connector ratio equals 0.72, the longitudinal and vertical slip ability are respectively raised by 22.5% and 25.0% compared with λ = 0.