Strengthening of masonry arches with Textile-Reinforced Mortar: experimental behaviour and analytical approaches

The continuous and growing interest in the conservation of historical heritages requires easy to use and reliable strengthening systems with related calculation methods that allow evaluating the capacity of existing and strengthened masonry structures. However, the analytical models applicable to retrofitted masonry structures have not been developed at the same level as those of other modern construction materials. In particular, there is a gap between the experimental results of masonry elements strengthened with innovative systems and the predicted structural behaviour provided by analytical models. This can hinder exhaustive analysis of experimental results and potentially led to over conservative design methods for innovative strengthening solutions. The present work investigated the performance of the Basalt Textile Reinforced Mortar (BTRM) strengthening system, applied to stone masonry arches, and evaluated the applicability of three different analytical approaches for design purposes. The basic materials and the BTRM composite were tested for the definition of the main constitutive laws. Three unreinforced stone masonry arches and nine arches retrofitted according to three different layouts were tested under vertical monotonic load. The experimental and analytical results were compared for the identification of the more suitable analytical approach for design purposes.