No abstract

The paper presents the results of experimental testing of six masonry rings built to technical scale and strengthened with CFRP strips and sheets and also with an FRCM system with PBO, glass, basalt and carbon fibers. The rings were subjected to tensile loads induced by four hydraulic jacks. The assumption is that the masonry rings are a representative simplification of domes, especially their structural support. Both single layered domes and ribbed domes are exposed to tensile stress in up to one third of their height.During the tests, the following information was collected: loads, displacements, strains of composites and failure modes. In some cases, an initial prestressing of reinforcements was carried out. Recommendations and limitations related to the use of the materials tested for reinforcing round, masonry structures under tensile stresses are discussed. The criterion for choosing the best solution was not only based on comparing the tensile strength of the reinforcement but also its stiffness. A strengthening efficiency index is proposed. The assessment of strengthening effectiveness was carried out, taking into account also heritage building conservation standards. Adopting the EF indicator as the criterion for assessing the effectiveness of reinforcement, it can be concluded that the application of the following methods should be considered in the structural maintenance of historical buildings: PBO mesh reinforcement in the PBO-FRCM system, carbon mesh reinforcement in the C-FRCM system and also basalt reinforcement in the B-FRCM system.

The paper presents the results of experimental testing of six masonry rings built to technical scale and strengthened with CFRP strips and sheets and also with an FRCM system with PBO, glass, basalt and carbon fibres. The rings were subjected to tensile loads induced by four hydraulic jacks. The assumption is that the masonry rings are a representative simplification of domes, especially their structural support. Both single layered domes and ribbed domes are exposed to tensile stress in up to one third of their height.During the tests, the following information was collected: loads, displacements, strains of composites and failure modes. In some cases, an initial prestressing of reinforcements was carried out. Recommendations and limitations related to the use of the materials tested for reinforcing round, masonry structures under tensile stresses are discussed. The criterion for choosing the best solution was not only based on comparing the tensile strength of the reinforcement but also its stiffness. A strengthening efficiency index is proposed. The assessment of strengthening effectiveness was carried out, taking into account also heritage building conservation standards.