Prolonging life time of old steel and steel-concrete bridges

Background

In the network of the European transport infrastructure (road and rail) a variety of different types of steel bridges exists. In addition to the relatively old bridge stock, effects of the climate change and increasing of the traffic load are major challenges to maintain the required structural safety level, satisfied serviceability and durability requirements of structures. Rather many of old bridges are listed as the cultural heritage, therefore a replacement of these structures is not easily possible and therefore appropriate concepts for repair and strengthening are required. In addition, due to the lack of knowledge and experience in older bridges structural benefits of composite action of concrete deck and the steel girders were not utilized, meaning no interaction between steel and deck exists because of the lack of devices for longitudinal shear transfer. Although the bridge types vary much from country to country, the variety of steel bridge types in Europe is illustrated by numbers from the Netherlands in figure 2 below.

This project is based on three distinctive ideas which each have the potential of saving large money for the European community. Furthermore, saving old bridges reduces the environmental impact as well as the traffic disturbance for trains and cars travelling on (and sometimes under) the bridges.

• Introduction of composite action or strengthening of existing shear connectors by post installed shear dowels

• Introduction of box action by horizontal trusses between the bottom flanges for I-girder bridges, transferring the very fatigue-sensitive I-girders into box girders

• Effective methods of strengthening old truss bridge

Financing

The project PROLIFE (Prolonging life time of old steel and steel-concrete bridges ) has received funding from the European Union’s Research Fund for Coal & Steel (RFCS) research programme under grant agreement n° RFSR-CT-2015-00025.

http://ec.europa.eu/research/industrial_technologies/rfcs_en.

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