A parametric study for the structural assessment of multi-ring masonry arches considering influencing factors

The vast majority of historically significant buildings with large spans are built with curved masonry elements, such multi-ring arches, to attain greater overall thickness. The ultimate capacity assessment of multi-ring arches' ability to withstand external forces is significantly influenced by the various construction techniques utilized. Since such structures are made up of independent rings that are connected to one another through interface contacts, the arrangement of the units and internal mechanical characteristics like friction have a significant impact. Furthermore, it is clear that geometrical features have an important influence on how these assemblies respond. In the evaluation of multi-ring arches under the vertical load at quarter span using an inhouse code (ALMA – Analisi Limite Murature Attritive) that corresponds to the upper bound limit analysis technique, an extensive combination of these factors, namely, friction angle, disposition and size of blocks, number of rings and span, are taken into account. Following their combination of impacts in terms of collapse multipliers, which are classified as per respective influencing parameters, each parameter's importance is demonstrated. It is demonstrated that the interlocking effect from the placement of units and the friction angle affect the overall structural behavior for different spans and varied shapes.