SPATIAL STABILITY DESIGN OF FREE STANDING TUBULAR ARCHES OF A ROAD BRIDGE

摘要

This paper sets out to investigate the spatial stability of twin free standing arches of a road bridge recently under construction. The bridge is located in the southern part of Austria crossing a branch line of the newly built Koralm high speed railway line from the city of Graz to the city of Klagenfurt. The bridge is composed of concrete cantilevering abutments, a composite deck and steel circular arches with tubular cross section. The arches are arranged in a basket handle scheme, spanning 30 m and the bridge deck is suspended from them by means of twin hangers consisting of round steel bars. This paper focuses on the stability design according to Eurocode 3 of the steel arches. The critical elastic buckling loads (eigenvalue) of the entire system (including abutments) is determined numerically and the plastic strength is determined for the arches only with a separate FE-Model. Finally full non-linear FE-analyses are carried out to determine the actual ultimate load. In conclusion, the suitability of the design after Eurocode 3 is determined.