Accounting for material strength in the thrust line analyses of unstrengthened and strengthened arches

This paper presents a methodology, based on Heyman’s safe theorem of limit analysis for masonry structures, to allow for the design and analysis of arches both unstrengthened and strengthened with composite materials. More specifically, we propose an extension of the Thrust Line Analysis to account for the expansion or contraction of the geometric domain of the thrust line able to include the effects of the limited compressive strength of masonry as well as the tensile strength and the delamination ruptures of the composite material. The influence of each one of these issues on the size of the admissible domain, evaluated iteratively as a function of the internal forces, is numerically investigated and discussed.