Fiber-based sectional analysis of urm walls with single-side FRCM strengthening

Abstract

Recently, research community has shown a growing interest in inorganic matrix composite materials (referred to as Fiber Reinforced Cementitious Matrices, FRCMs, or Textile Reinforced Mortars, TRMs, or Inorganic Matrix-Grid composites, IMGs) as an effective solution for external strengthening of existing masonry walls. Such composites are typically made of a composite grid immersed in an inorganic mortar, making their mechanical behavior different from conventional fiber reinforced polymers, FRPs. While the in-plane behavior of unreinforced masonry (URM) walls strengthened with FRCM systems has been investigated through extensive experimental campaigns and numerical approaches, a comprehensive understanding of the out-of-plane behavior is still lacking, with particular reference to failure modes, analytical formulations and effects of different FRCM strengthening systems. In the present work, the available experimental outcomes on the out-of-plane behavior of strengthened URM walls are firstly collected, encompassing different URM types, eccentric load applications, FRCM strengthening systems. Then, a fiber-based sectional model of URM walls with single-side FRCM strengthening is proposed and validated with proper experiments. The tensile behavior of FRCM systems is modelled considering different characteristic phenomena of such materials, i.e. matrix cracking and fiber sliding. The results of the fiber-based analysis are in good agreement with experiments.