Effect of Disposable Medical Facemask Fiber Content on Strength, Impact Resistance, and Water Absorption of High-Strength Concrete

Human health is a major focus of the international public reaction to the COVID-19 (SARS-CoV-2) pandemic. An increasing usage of medical facemasks has warned of significant threats to the environment. Therefore, it is crucial to utilize these masks to lead to an environmentally sustainable development. The aim of this study was to assess the effect of disposable medical facemask (DMFM) fiber content on compressive and flexural strengths, impact resistance, and water absorption of high-strength concrete. The amounts of DMFM fibers were added at 0, 0.3, and 0.5% by volume of concrete, along with polypropylene (PP) fibers applied at the same dosage for comparison. A ratio of water-to-cement was kept constant at 0.37 for all the mixture proportions. The results showed the addition of DMFM fibers did not affect the compressive strength of hardened concrete regardless of curing ages; however, it decreased the flexural strength. All mixture proportions still achieved the designed compressive strength of high-strength concrete (i.e., above 70 MPa). The concrete samples containing DMFM fibers resulted in higher impact resistance and water absorption than the reference concrete samples without fibers. When comparing with DMFM fiber reinforced concrete, the use of PP fibers showed more effectively for compressive and flexural strengths, impact resistance, and water absorption of hardened concrete. In general, in this study, 0.3% DMFM fibers would be an optimal amount, which can significantly improve the impact resistance of hardened concrete.