ORIGINAL ARTICLE Strengthening of masonry arches with Textile-Reinforced Mortar: experimental behaviour and analytical approaches Leire Garmendia • Ignacio Marcos • Enrico Garbin • Maria Rosa Valluzzi Received: 16 October 2013 / Accepted: 16 May 2014 Ó RILEM 2014 Abstract 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 retrofit- ted 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 strength- ened 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 evalu- ated the applicability of three different analytical approaches for design purposes. The basic materials and the BTRM composite were tested for the defini- tion 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 ana- lytical results were compared for the identification of the more suitable analytical approach for design purposes. Keywords Masonry arch  Strengthening  Composite material  Analytical methods  FEM  Limit analysis 1 Introduction The continuous and growing interest in the preserva- tion of historical heritage requires easy to use and compatible strengthening systems together with reli- able calculation methods that allow the mechanical capacity of existing masonry structures to be estimated [37]. One of the key factors in the selection of a strengthening system is its compatibility with the substrate or structure. In this article, the Textile L. Garmendia (&) TECNALIA, Parque Tecnolo ´gico de Bizkaia, Edificio 700, 48160 Derio, Spain e-mail: leire.garmendia@tecnalia.com URL: http://www.tecnalia.com L. Garmendia  I. Marcos Department of Mechanical Engineering, UPV/EHU, c/Rafael Moreno ‘Pitxitxi’ n8 2, 48013 Bilbao, Spain e-mail: ignacio.marcos@ehu.es E. Garbin  M. R. Valluzzi Department of Civil, Environmental and Architectural Engineering, University of Padova, Via Marzolo 9, 35131 Padua, Italy e-mail: enrico.garbin@dicea.unipd.it M. R. Valluzzi e-mail: valluzzi@dicea.unipd.it Materials and Structures DOI 10.1617/s11527-014-0339-y