Influence of railway loading on the performance of soil-filled masonry arch bridges

There is a large number of masonry arch bridges on the rail networks in Europe and other parts of the world. However, the mode of response of masonry arch structures subjected to railway loading is little understood. To address this, an experimental study involving large-scale physical models of backfilled masonry arch bridges subjected to railway loading conditions was conducted. The study explored the influence of the rail track–bed system on bridge behaviour and load-carrying capacity. The tests results indicated that the track–bed system fundamentally alters the mode of response of the bridge system and significantly increases load-carrying capacity. Using the same test facility, load tests were also used to explore and characterise the behaviour and performance of damaged arch bridges. The results obtained suggest that, although there is likely to be a reduction in overall capacity, even a significantly damaged arch bridge can still perform adequately under loading. This has important implications for bridge owners and assessment engineers.