APPLIED ELEMENT MODELLING OF MASONRY ARCHES STRENGTHENED WITH FRCM

This paper describes a discrete element numerical model of masonry arches validated through a series of experimental tests, developed within an Applied Element Method (AEM) framework. The study assesses the effectiveness of strengthening masonry arches using a fibre-reinforced cementitious mortar (FRCM) coating (Planitop Intonaco Armato®) applied to the extrados. Following the validation of the AEM-based numerical model with experimental results of both unreinforced and strengthened (using FRCM in combination with polybenzoxazole (PBO) fabric) masonry arches, the model has been further employed to analyse the use of the FRCM material Planitop Intonaco Armato. The strengthening measure was modelled using a simplified grid-based approach, representing the retrofit as a single layer of springs at the extrados, an approach initially validated against experimental tests. As result, numerical analyses were conducted to evaluate the impact of the FRCM strengthening system on load-carrying capacity, post-peak behaviour, and failure mechanisms. While previous validation analyses indicated that the AEM framework accurately reproduces the experimental performance of URM arches and effectively predicts the enhancement provided by the retrofit, the findings underscore the potential of the FRCM Planitop Intonaco Armato as a viable alternative strengthening solution. Preliminary sensitivity analyses revealed its effectiveness is greater when the unreinforced masonry arch has weaker material properties, but its beneficial impact diminishes as the material properties of the arches improve.