Durability and bond behavior of textile-reinforced mortar composites under prolonged saline exposure

The durability of textile-reinforced mortars (TRMs), also known as fabric-reinforced cementitious matrices (FRCMs), is a critical factor in the structural rehabilitation of existing masonry buildings, particularly in aggressive environments. Although various exposure scenarios have been addressed in prior research, the long-term effects of saline environments on TRM systems remain insufficiently characterized. This study investigates the mechanical response of TRM composites incorporating glass and basalt fiber textiles embedded in a lime-based mortar matrix, after exposure to a 3.5% NaCl solution for durations of 1000, 3000, and 5000 hours. The evaluation included compressive and flexural testing of the mortar, tensile testing of dry textiles, and bond performance assessments through both pull-out and single-lap shear configurations. Results revealed an initial enhancement in interfacial behavior due to chloride-induced hydration, followed by progressive degradation characterized by calcium depletion, salt crystallization, and reduced post-peak ductility. Glass-based systems exhibited a consistent reduction in bond strength, while basalt-based systems showed transient gains prior to brittle failure. The findings underscore the significance of fiber type and exposure duration in the design of TRM applications for marine or coastal structures. • Investigated long-term performance under saline, water, and dry conditions. • Conducted 1000, 3000, and 5000-hour exposure tests on glass- and basalt-based TRM. • Used XRD to detect changes in mortar composition under various aging conditions. • Analyzed bond performance of basalt vs. glass fibers in saline conditions. • Dual role of chlorides in accelerating hydration and long-term degradation.