Flexural bearing capacity of RC hollow slab beam strengthened by steel plates of different thicknesses

Abstract

PurposeThe flexural reinforcement of bridges in-service has been an important research field for a long time. Anchoring steel plate at the bottom of beam is a simple and effective method to improve its bearing capacity. The purpose of this paper is to explore the influence of anchoring steel plates of different thicknesses on the bearing capacity of hollow slab beam and to judge its working status.Design/methodology/approachFirst, static load experiments are carried out on two in-service RC hollow slab beams; meanwhile, nonlinear finite element models are built to study the bearing capacity of them. The nonlinear material and shear slip effect of studs are considered in the models. Second, the finite element models are verified, and the numerical simulation results are in good agreement with the experimental results. Finally, the finite element models are adopted to carry out the research on the influence of different steel plate thicknesses on the flexural bearing capacity and ductility.FindingsWhen steel plates of different thicknesses are adopted to reinforce RC hollow slab beams, the bearing capacity increases with the increase of the steel plate thickness in a certain range. But when the steel plate thickness reaches a certain level, bearing capacity is no longer influenced. The displacement ductility coefficient decreases with the increase of steel plate thickness.Originality/valueBased on experimental study, this paper makes an extrapolation analysis of the bearing capacity of hollow slab beams reinforced with steel plates of different thicknesses through finite element simulation and discusses the influence on ductility. This method not only ensures the accuracy of bearing capacity evaluation but also does not need many samples, which is economical to a certain extent. The research results provide a basis for the reinforcement design of similar bridges.