Cementless ultra-ductile composites reinforced by polyethylene-based short selvedge fibers for sustainable and resilient infrastructure

This paper introduces new, sustainable and ultra-ductile cementless composites in which cement and fibers were entirely replaced by by-products, i.e. alkali-activated materials and short selvedge fibers, respectively. Four mixtures were designed with two different alkali-activated materials using slag and fly ash, respectively, as precursors and two different reinforcing fibers, i.e. normal polyethylene (PE) fibers and PE fiber-based short selvedge fibers. To investigate the compressive strength and tensile behavior of each mixture, specimens were prepared and tests were performed. Test results showed that the cementless composites reinforced by short selvedge fibers had high tensile strength over 7.0 MPa and ultra-ductility over 8.9%. It was found that the sustainability, evaluated based on material sustainability indicators (MSI), i.e., embodied energy, carbon dioxide emission, and material cost, of composites improved significantly when cementless binders and short selvedge fibers were used simultaneously. Furthermore, the average tensile toughness values per MSI of cementless composites reinforced by short selvedge fibers were 1.3 times to 12 times higher than those of previously reported representative highly ductile composites.

Automated summary

This paper presents a new type of sustainable and ultra-ductile cementless composites. By replacing cement and fibers with alkali-activated materials and short selvedge fibers, respectively, the composites show improved compressive strength and tensile behavior. The sustainable indicators, including embodied energy, carbon dioxide emission, and material cost, are significantly enhanced by incorporating cementless binders and short selvedge fibers. Additionally, the tensile toughness of the composites reinforced by short selvedge fibers is 1.3 to 12 times higher than that of previously reported highly ductile composites.