Degradation of the Long-Term Operated Metallic Bridge Materials and Its Rehabilitation Using Composite Structures

The paper presents issue devoted to the mechanical properties of the old metallic materials extracted from 19th- century bridge structures located in the Lower Silesian region in Poland. Particular attention was paid to the problems of material mechanisms and microstructural degradation of puddle iron extracted from 19th-century bridges located in Poland. Also, an important issue considered in this paper is the application of the composite materials in civil engineering as supporting materials in rehabilitation of the long-term operated metallic structures. The main advantages of the composite materials are high resistance to corrosion and much better the strength/weight ratio. In the bridge engineering, more and more often a tendency is observed for applying those materials as structural components of bridge decks. In the work an example of practical use of the composite components as surface of deck for servicing a conveyor in the suspended technology bridge over the Odra river. The direct cause for exchange of the surface layer at the deck of the technology bridge was the state of the primary structure made of riffled sheets covered with the cast asphalt layer. The advanced degradation processes in grating components of the hanging bridge span forced their repair works and complete exchange of the deck surface to the Fiberline components of the sidewalk grating type and under the conveyor of the Plank type. Two types of material structure i.e. the „grating” type structure and the „Plank” type panels were subjected to strength tests. Mechanical properties of both material groups were compared and the basic strength parameters determined. The strength tests have confirmed validity of applying those structures as structural components in bridge engineering.