Evaluation of Reutilizing Single-Use Surgical Face Mask in Concrete

Abstract

The outbreak of coronavirus disease (COVID-19) caused a sharp increase in the utilization of Single Use Surgical Face Masks (SUSFM) around the world as personal protective equipment. These eventually ended up in waste disposal facilities, causing environmental pollution. Incineration of the SUSFM produces greenhouse gases that eventually contribute to global warming. Those that ended up in the water bodies fragments into microplastics that affect marine life and find their way into the human food chain. SUSFM materials are made from polypropylene, a thermoplastic polymer material that takes a long time to degrade. It was therefore, important to develop low carbon mitigation measures to remove these wastes from the environment. Concrete, as construction material, is strong in compression but brittle and weak in tensile strength. Hence need for reinforcement to improve on its qualities. Therefore, the main aim of the study was to evaluate the feasibility of re-utilizing single-use surgical face masks in concrete. In the study, SUSFM were shredded into 5 mm widths and 20 mm, 30 mm, and 40 mm lengths. The SUSFM were blended with C30 grade concrete in various percentages by mass of cement content, ranging from 0% (control mix) with incremental of 0.5% to 3.0%. The effect on workability, water absorption, and density were tested to BS standards for concrete blend with 20 mm long SUSFM material. Compressive strength, ultrasonic pulse velocity, and splitting tensile strength were tested to BS standards on varied contents and lengths of SUSFM in concrete. Acid attack and abrasion resistance were tested for durability of blend concrete. The addition of SUSFM material to concrete reduced its density by between 1.5% and 7.7% while water absorption increased from 16.9% to 70.8%. The addition of SUSFM materials decreased the workability of fresh concrete. Compressive strength decreased with minimum loss registered at 0.5% dosage of 30 mm length of SUSFM material. Splitting tensile strength improved to an optimum of 15.2% at 0.5% dosage of 30 mm SUSFM material. Further, the overall concrete quality remained at more than 4000 m/s UPV values. There was a notable decrease in acid attack resistance when exposed to hydrochloric acid conditions, but the abrasion resistance of concrete improved up to optimum dosage of 1.5% SUSFM fiber material, beyond which it decreased. The results underscored the crack bridging effect of SUSFM material in concrete. The composite concrete with 0.5% of 30 mm SUSFM fiber material can be used by design engineers to design structures that require improved tensile strength and abrasion resistance as compared to plain concrete. This is a low-carbon strategy for improvement of concrete strength at the same time safely disposing the SUSFM material to reduce the environmental pollution and global warming. Further studies are recommended on the effect of SUSFM materials at smaller widths and lengths on concrete