Multi-scale experimental investigation on the structural behaviour of novel nanocomposite/natural textile-reinforced mortars

Natural fibre composites present a very appealing area of research for the structural strengthening of masonry structures. Natural fibres possess several drawbacks, such as low initial stiffness and poor interfacial bond behaviour with inorganic matrices that hinder their functions. Such challenges were overcome by applying an innovative nanocomposite-based impregnation system that was pre-engineered and presented by the authors previously. In this paper, a full experimental study involving pullout, tensile tests and large-scale testing via diagonal compression test was carried out to evaluate the structural efficiency of the developed system. Remarkable improvement at yarn-to-matrix level upon nanocomposite coating was observed. At a medium bond length, yarn rupture was observed, highlighting the great anchorage provided by the nanocomposite coating within the matrix. Coupons cast with the developed system demonstrated outstanding composite behaviour and multicracking under tensile loading. Finally, wallets strengthened with the developed system displayed multiple cracks and maintained high shear capacity (40–60 % of τmax ) at remarkably large displacements developed at later stages of the test. Such ductility is crucial for retrofitting masonry structures, especially in seismic areas. • Remarkable improvement at yarn-to matrix level upon nanocomposites coating. • Nanocomposite coating increased pullout load by 525 % for 30 mm, 420 % for 50 mm, and 425 % for 70 mm bond lengths. • Remarkable composite behaviour and strain hardening were attained by nanocomposite-coated textiles. • NTRM-strengthened wallets maintained high shear capacity at remarkably large displacements developed at later stages.