RESUMO
Human activities significantly contribution to the yearly generated plastic wastes. Moreover, the enormous increase in face masks and face shields caused by the emergence of the COVID-19 pandemic has doubled the generated plastic wastes. Although there is an added benefit of using plastic waste in construction, the cost associated with their application, specifically the face mask, has not been addressed. This paper presents a simplified and rapid estimation of the cost associated with the collection, processing, and application of face masks in hot-mix asphalt (HMA) pavements. Two scenarios, mask modified asphalt pavement and conventional asphalt pavement, are considered. The total cost is based on market price and prices from waste management facilities and plastic processing companies. Life Cycle Cost Analysis (LCCA) is used to evaluate the long-term costs of mask modified asphalt pavement and conventional asphalt pavement. Results show that no significant difference in initial total cost between the two scenarios for pavement sections with lengths less than 500m and the number of lanes less than 6. The difference in total cost begins with lengths greater than 500 m for 5 and 6 Lanes. Despite the higher initial costs for the mask modified asphalt pavement, the LCCA shows that there is a 29% maintenance cost reduction over the 40 years life cycle of the asphalt pavement. The use of LCCA shows the benefit of the selection of the most cost-effective strategy and how the use of mask modified asphalt pavement over the conventional asphalt pavement can save money over the life cycle of the asphalt and improve rutting and stiffens.
RESUMO
Today, the world faces an enormous increase in plastic waste pollution caused by the emergence of the COVID-19 pandemic. Plastic pollution has been already one of the greatest threats to our planet before the Coronavirus outbreak. The disposal of millions of personal protective equipment (PPE) in the form of face masks has significantly contributed to the generation of plastic waste and has exacerbated plastic pollution. In an attempt to mitigate pollution caused by the excess PPE waste, an innovative way was developed in this research to reduce pandemic-generated wastes by using the shredded face mask (SFM) fibers as an additive to hot mix asphalt (HMA) to enhance rutting resistance. Rutting or permanent deformation is one of the major distresses of asphalt pavement. Since the SFM behaves as a semi-liquid between 115.5 and 160 °C, which is in the range of HMA mixing and paving temperature, it can function as a binding agent to glue the aggregates. When the pavement is cooled down to ambient temperature, the hardened SFM can provide stability and stiffness to HMA. Based on the results of this study, the modified mixes exhibited excellent resistance to permanent deformation under the Asphalt Pavement Analyzer (APA), as rutting depth values were reduced from 3.0 mm to 0.93 mm by increasing the SFM content from 0% to 1.5%. From the rutting test results and premature distress mechanism study, the appropriate addition of SFM modifiers could improve the high-temperature properties of HMA that can be used to strengthen high-compression and shearing zones in the pavement structure.
