Mechanical Role of Spandrel Walls on the Capacity of Masonry Arch Bridges

In the presented work the mechanical behavior of a masonry arch bridge of a single-track railway is analyzed numerically. The 3D discrete element model contains the arch barrel, the backfill and the spandrel walls as well. Every voussoir is represented by a discrete element, while the backfill is modelled as an elasto-plastic continuum. Between the elements zero-thickness nonlinear interfaces can be found where mechanical interaction can take place. Static analysis has been carried out to investigate the effects of spandrel walls on load bearing capacity and structural stiffness. Failure modes of spandrels due to the excessive lateral displacement of the backfill are identified.