Mechanical properties of flax fibers as a green alternative for FRCM systems

Abstract

In recent years, thanks to policies oriented toward the rehabilitation of existing heritage and the introduction of more environmentally sustainable choices, an increased attention has been devoted to the study of new structural strengthening solutions. With reference to masonry buildings, which constitute a significant part of the built heritage, Fiber Reinforced Cementitious Matrix (FRCM) systems are widely adopted to achieve more effective structural capacity, making use of inorganic matrices and composite grids, the latter being formed of carbon, basalt, glass, or aramid fibers. However, the necessity to reduce the carbon emissions, also considering the new European perspectives on sustainability, have prompted the scientific and engineering community to explore eco-friendly alternatives. In this context, the use of natural fibers as potential alternatives for enhancing the structural performance of a building or part of it, rises as a promising area of study. The present study proposes an analysis on the use of flax fibers within FRCM systems, aimed at reinforcing masonry structures. The mechanical and durability properties of the material are investigated through tensile tests on flax yarns, as well as tests on a fabric composed by flax bundles supported by a mesh of glass fibers. The results obtained in this study shaw how the natural type of fiber studied is so interested when it is treated with coating in terms of mechanical properties and durability.