Diagnostics and Evaluation of Bridge Structures on Cogwheel Railway

Abstract

The paper is focused on diagnostics and calculation of load-carrying capacity of the two bridge objects on cog railway (cogwheel railway) Tatranská Štrba – Štrbské Pleso in Slovakia. The bridges are situated in the north part of Slovakia in the mountains of the High Tatras and bypass the road way. The bridge objects were built during 1968–1969, so, they are 52 years old bridges. The bridges are made from precast prestressed post-tensioned beams of three single spans. In the transverse direction, the beams are not coupled by a slab, but act as a “curtain slab”. The peculiarity is that these are prefabricated beams intended for road bridges. In 2020, the Department of Structures and Bridges, the Faculty of Civil Engineering, University of Žilina, was asked to carry out the technical survey and diagnostics of the above-mentioned bridge. The visual inspection, diagnostics, verifying real dimensions and material characteristics were requested. After that, calculation of the load-carrying capacity was done. For determining the load-carrying capacity, the standard approach given in Eurocodes was used according to provisions, which take into account the modified (lower) reliability levels and their adequate partial safety factors according to Eurocodes.