Structural Assessment of Concrete Bridges in Germany-Shear Resistance under Static and Fatigue Loading

The demands on the load-carrying capacity of bridges have increased over the last few decades because of the higher traffic volumes and weights. In the future, an even greater increase is expected. Since a large part of the existing bridges in Germany was built in the 1960s and 1970s, the assessment of these structures is deemed crucial. Therefore, the German Ministry of Transport introduced guidelines in 2011 allowing for a more accurate determination of the bearing capacity compared to the current German bridge design code. Nevertheless, many concrete bridges show deficits in shear and fatigue resistance. Consequently, a supplement to the guideline was published in 2015 to incorporate new research results. This paper describes the approaches for static and fatigue shear verification that consider the provided shear reinforcement. These methods refer to a truss model with variable compression strut inclination. Further, an application to a typical box-girder bridge in the road network is presented, demonstrating the potential for increasing the design value of the bearing capacity.