Evaluation of the safety coefficient of axi-symmetric masonry domes with drum and lantern having variable profile and carrying their own weight

The objective of this work is to present a method suitable for determining the safety coefficient of axi-symmetric masonry domes having lantern, drum and variable profile, made of stones dry assembled or connected with poor mortar, carrying their own weight. In the hypothesis of geometrical, mechanical and loading symmetry it is possible to study a spherical sector only, adequate to describe the static behavior of the entire structure. The main mechanical features are: discretization in rigid macro-blocks containing some number of stones or bricks; slide between the blocks with dilatancy; inability to carry tension; limited compressive strength. The evaluation of safety coefficient is founded on the utilization of limit analysis static theorem and it is obtained determining the load multiplier that defines the collapse mechanism. The optimization of solution is obtained with Excel’s Solver. At last, the collapse mechanism has been found.