Safety analysis of existing masonry arch bridges by nonlinear finite element simulations

In order to simulate the specific load-carrying behavior of masonry arch bridges, nonlinear finite element analyses may be carried out. To that end, an associated analysis concept is proposed in this paper. The applied smeared crack model allows one to realistically reproduce characteristic damage patterns observed at existing bridge structures of this type. By using the proposed analysis concept, load-bearing reserves may be revealed and possible causes for existing damage may be identified. The concept includes appropriate failure criteria and corresponding safety margins. The latter approximately conform to valid design codes, but also account for the specifics of nonlinear analyses. In parametric studies, the objectivity of the analysis results and influences of different material parameters on the load-bearing behavior were investigated. Furthermore, two examples of the safety evaluation of existing masonry arch bridges are presented. In both cases, observed damage patterns could be reproduced in the numerical simulations. Destructive load tests at a disused bridge provided an additional opportunity to validate the proposed analysis concept.