Innovations in concrete arch bridge design

Abstract

Innovation in the design and construction of large-span arch bridges was investigated by considering buildability, maintainability and durability factors and their interaction at the design stage in terms of their effects on quality of construction and whole-life costs. In this study the utilisation of innovative composite arch ribs was examined and comparisons were made with concrete and steel arch ribs. A parametric study of a new composite arch rib was performed for a two-hinged arch in the span range 300–1000 m. The arch cross-section comprised three steel trusses interconnected by concrete slabs in composite action with the top and bottom truss chords. The results appeared promising for the span range 300–600 m in comparison with the steel arch and therefore the composite arch rib was tested in a new Croatian arch bridge carrying the highway over the Krka river. The fixed arch has a 204 m span and a rise of 52·0 m with a rise-to-span ratio of f/l=0·25.