Curvature Limitations for Concrete Box-Girder and Solid Slab Bridges

Abstract

In bridges with light curvature, curvature effects may be ignored if they are within acceptable range. In contrast to ACI 343R, the Canadian Highway Bridge Design Code, AASHTO Guide Specifications for Horizontally Curved Bridges (American Association of State Highway and Transportation Officials), and AASHTO-LRFD Bridge Design Specifications specify certain limitations to treat a horizontally curved bridge as a straight one in structural design. However, these limitations proved to be inaccurate in estimating the structural response. To investigate the accuracy of these limitations, a series of curved concrete cellular, multi-box, and solid-slab bridge configurations were analyzed in this study using finite element modeling to investigate their behavior under dead loading. The major internal forces developed in the members were determined and then compared with those obtained for straight bridges of identical configuration. The stipulations made in bridge codes for treating a curved bridge as a straight one were proven unsafe when correlated with the finite element analysis (FEA) results. As such, sets of empirical expressions were developed to determine such limitations more accurately and reliably.