Stability behaviour of concrete arch bridge structures in relation to the load direction out of the arch’s plane

Arches are one of the predominant structural elements for bridges with big spans. With the current technological advancement, they are applicable in pure form, without any transverse stabilizing systems. The slender form of the arch elements leads to reduction in their capacity due to stability failure. Their behaviour is directly related to the presence of first and second order effects – imperfections and deformed state. The typical bridge loads and combinations, often invoke effects outside of the elements’ plane of reference. Such conditions are reducing the capacity of the structure in relation to magnitude of the effect. Analysis of such effects is complex task including interaction between complex stress state, 3-dimensional geometry, and non-linear material behaviour. In the following work are presented series of geometrical configuration in condition of material and geometrical non-linearity for the determination of critical load leading to stability failure. The results display trends in the stability behaviour of reinforced concrete arch bridge elements.