Improved approximation procedure for hollow stiffeners of orthotropic deck plates

Orthotropic deck plates of steel bridges are often built with trapezoidal hollow stiffeners. The calculation of the longitudinal ribs and the deck plate can be performed by simplified assumptions with extracted subsystems or complex models based on the finite element method. The latter usually requires a lot of effort as well as experience and good knowledge of the user in order to avoid errors in the modelling. Therefore, the deck plate and the longitudinal ribs are generally examined as individual systems. For the usual approximation procedures, this results in significantly overestimated internal forces, especially in consequence of wheel loads. The optimization of this calculation method shows that the stresses in the longitudinal ribs and in the deck plate can be determined better under wheel loads and come very close to the results of the FEM.