The Road Steel Bridge Over Bosut River in Serbia Part 2 – Repair and Reconstruction

AbstractThe paper presents an approach to repair and strengthening of the road steel bridge over Bosut river in Serbia. In the previous period, bridge structure suffered serious damages, including: corrosion of steel material, dysfunctionality of pillar bearings, deterioration of dilatations, cracked asphalt pavement layer and other mechanical damages. Firstly, in order to choose a proper repair technique, identification of basic material was performed by analyzing the mechanical properties of the samples, taken from the steel elements. Following the identification of a steel class, allowable stresses and ultimate stresses of structure were determined. All types of loads in the previous service life of the bridge, as well as possible loads for the future exploitation, were considered. The realization of repair is divided into three execution phases. The first phase includes restoring bridge to proper condition: the repair of corroded and deformed steel elements, repair of bearings, dilatation enabling, repair of river piers, anticorrosion protection and new pavement layer. Second phase refers to the improvement of traffic characteristics of the bridge, i.e. improvement of traffic flow by pavement enlargement. In addition, possible measures to improve the characteristics of the bridge structure were given and include the construction of new piers with supports in place of the current joints, which represents a possible replacement of the basic structural system (third phase)