Numerical investigation of arches in brick-masonry bridges

A significant number of old masonry bridges are still in use and need to be assessed considering current traffic loading and safety requirements. Masonry bridges are complex heterogeneous systems, where masonry arches represent the main components. Thus, a realistic modelling of arches is vital for accurate assessment of masonry bridges. The authors have previously proposed and validated a detailed mesoscale description for masonry arches allowing for the actual masonry bond and the specific arch geometry including the case of skew arches. In this paper, the proposed mesoscale modelling strategy is used in a comprehensive numerical study to investigate the effects of various parameters, including masonry bond and defects in the brickwork, abutment stiffness and movements at the supports, which are usually disregarded in practical assessment of masonry arches and bridges. The results achieved show how these parameters affect the ultimate load capacity, failure mechanisms and initial stiffness of square and skew arches, where the use of detailed 3D mesoscale modelling is critical in providing accurate response predictions under a variety of loading conditions for which reduced models might provide incorrect results.