A Long-span Network Arch Bridge for Road and Rail Traffic

The Qilu Huanghe River bridge, which is designed to span the Huanghe River and carry both road and rail traffic, is a network arch bridge with a record-breaking span of 420 m. This bridge has the characteristics of a long span, road and rail traffic and wide decks, making it a focus of many studies and examinations. This study highlights the case features and structural characteristics of the bridge. As a key issue in optimizing the design of network arch bridges with large spans, a parametric study of the hanger arrangement is carried out considering both aesthetic and structural mechanics. To meet the fatigue requirement of network hangers under road and rail traffic, strands with a high fatigue stress amplitude of 400 MPa are explored and proven to be safe and reliable according to fatigue and tension tests. Extensive FEM calculations and economic studies are carried out for an ortho-composite deck, and the results show a much better fatigue resistance and a minimization of life cycle cost compared to standard orthotropic steel decks.