Effects of material and geometric non-linearities on the collapse load of masonry arches

This paper addresses the influence of both the constitutive and geometric non-linearities on the collapse load of masonry arches. The non-linear mechanical behavior of masonry is embedded into the constitutive equation, which assigns the generalized stresses to each pair of generalized strains, thereby accounting for the material's lack of resistance to tension as well as its limited compressive strength. We first apply the methods of limit analysis to explicitly evaluate the collapse load for various circular arches subjected to their own weight and either to a load uniformly distributed per unit span, or to a point load acting at the crown. Subsequently, in order to highlight the influence of P-δ effects, the collapse load is determined via an expressly developed numerical method that also accounts for the geometric non-linearity.