Finite Displacement Behavior of Curved I-Girder Webs Subjected to Bending

Abstract

Curvature greatly complicates the behavior of curved plate girders used in bridges. The out-of-plane “bulging” displacement of the curved web results in an increase in stress, which must be considered in the design of plate girders with significant curvature. This paper presents results from geometric nonlinear finite-element analyses used to evaluate the finite displacement behavior of such panels and to formulate deflection amplification factors that can be applied to analytical models to get conservative values for predicting the maximum displacements and stresses of the curved panel. Equations are developed that represent the reduction in nominal strength of the curved web due to the effects of curvature. The applicability of the method is demonstrated and a comprehensive comparison is made between the equations developed in this investigation and design equations used in Japanese and American design guides.