ABSTRACT

In orthotropic steel decks (OSD), the transverse distribution of wheel generates high local stresses in the small thickness of steel members. In order to reduce the stress level and thereby extend the fatigue life, a strengthening technique with overlaid UHPFRC (Ultra-High Performance Fiber Reinforced Concrete) was proposed and commonly used based essentially on experimental studies. In this study, three-dimensional finite element analysis with the nonlinear constitutive material model is performed to investigate the static behaviors, i.e. deflection and deformation, of steel bridge decks with and without the overlaid UHPFRC subjected to wheel-type loads, so that the beneficial effects of the UHPFRC overlay can be evaluated. It is found that the analytical results of the UHPFRC-strengthened bridge decks exhibit an acceptable agreement with the corresponding experimental results. The apparently decreases in deflection and strain level are observed in the FEM model. The influence of the overlaid UHPFRC thickness is also examined in the paper.