Centre-line optimisation of buried arch bridges

The arch is the oldest structural shape that mankind has invented. The Romans constructed a large number of stone arch bridges on roads or water supply routes (aqueducts), many of which have survived to the present day. Arch bridges were constructed throughout medieval times; some of them represent masterpieces of the world´s cultural heritage. Buried concrete arch bridges are built with spans from 2 m up to 40 m on roads and railways, both as underbridges or overbridges, and as pre-cast and cast-in-place structures. Owing to low construction costs, great durability and endurance, they are favoured by contractors and owners. This paper focuses on the structure–soil interaction of buried arch bridges both in operation and under construction. Based on analytical derivation, a method of centre-line optimisation of cast-in-place buried concrete arch bridges is proposed and applied on an existing structure. The method leads to reduction of bending moments and deflections, thus making the structural system more...