The maximum modulus eccentricities surface for masonry vaults and limit analysis

This paper presents a constitutive equation for masonry vaults which associ ates to each pair of generalized strains (Lambda, K), where Lambda are the strains, K are the curvature changes of the mean surface, the pair of gener alized internal forces, (N, M) with N and M being the normal forces and ben ding moments per unit length, respectively. The maximum modulus eccentricit ies surface is defined, and its main properties are proved. Subsequently, t he limit analysis for masonry vaults is set forth and applied to the evalua tion of the collapse load for a toroidal tunnel subjected to its own weight and an uniform load applied on the top circle.