Introducing a curauá fiber reinforced cement-based composite with strain-hardening behavior

Castable, cementitious short-fiber composites with ductile, strain-hardening behavior have been made using renewable curauá plant fiber. Using plant fiber reinforcement lowers the embodied energy of the material compared to that of previously reported strain-hardening cementitious composites, which have used synthetic, petroleum-based polymer fibers. In this study, physical, chemical, and mechanical characterization of the curauá fiber is conducted, followed by iterative design of curauá-reinforced cementitious composites. The aim of the research is to highlight and expand the range of functional uses for curauá fiber in construction applications, and to improve the sustainability of strain-hardening cementitious composites. Design challenges associated with using natural fibers in place of synthetic fibers in cement mortar matrices-including water absorption and disparate physical characteristics leading to weak fiber-matrix interfacial bonding-were addressed with silane coupling agent and mechanical fiber debundling treatments. The resultant curauá-reinforced composites are promising construction materials for building façade and cladding applications based on their lightweightedness, low thermal conductivity, and material toughness derived from a combination of tensile strength and tensile ductility.