A simple computation tool for the limit-state analysis of masonry arches

The paper deals with the limit-state analysis, with special attention to sliding mechanisms, of symmetric masonry arches made of rigid blocks with unilateral and frictional constraints. The validity of a limit analysis approach in presence of friction is discussed by taking into account the possibility of adopting associated flow rules in the problem. On these bases the collapse mechanisms of an arch in terms of the thickness and of a load multiplier have been pointed out using, with a lower bound approach, the simple optimisation-programming tool within everyone’s reach, such as the “Solver” of the programme Excel. Some numerical examples are given for a constant thickness arch underlining the strong influence of the friction coefficient in the analysis.