Analysis Model of Slip for Composite Box Girders

Abstract

The interface slip of steel–concrete composite beams was studied analytically and numerically. Based on the partial interaction theory, a theoretical solution for the theory of steel–concrete composite box beams with partial shear interaction was derived and equilibrium of the rotation angle w’ was introduced to account for the convenient computation of composite box beam deformation. Numerical simulations of steel–concrete composite box beams subjected to concentrated loads and uniformly distributed loads were conducted. The analytical solutions show an excellent agreement with the numerical results. For typical composite box beams used in practice, shear slip in partial composite box beams makes a significant contribution to beam deformation. Even for full composite box beams, slip effects may result in stiffness reduction. However, many design specifications that use transformed section methods ignore slip effects, except for the American Institute of Steel Construction (AISC) specifications, which recommend a calculation procedure in the commentary. Finally, the proposed method was extended to analyse the interface slip of shear connectors of different pitch and to some extent validate the accurate prediction.