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.
Display omitted
•Single-use face masks were used as an additive to HMA.•It provides a potential avenue to reduce Covid-19 pandemic-generated wastes.•The addition of SFM to HMA significantly reduced the rut depth.•SFM acted as a binding agent to bind the aggregates and reduce the rut depth.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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.
Asphalt pavements; Cost estimation; COVID-19, Face masks, Life cycle cost analysis (LCCA).
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
End-of-life tire (ELT) rubber has been widely researched to replace fine or coarse aggregates in cementitious composites. While most studies paid attention to its effect on the engineering ...properties, very few considered chemical reactions with pore solution and the potential for environmental leachate. Recently the authors developed a methodology to remove zinc from the ELT rubber, since zinc can be toxic if it is leached into the environment. In this study, the authors utilized ELT rubber before and after the zinc extraction process to partially replace fine aggregate in a mortar. Flowability, compressive strength, flexural strength, and ultrasonic pulse velocity were measured for the engineering properties of rubberized mortars. Simultaneously, isothermal calorimetry was also employed to investigate the effects of ELT rubber on the hydration process of the rubberized mortars. In addition, the pore solution and leaching solutions were taken at different curing ages and then analyzed for elemental and total organic carbon (TOC) contents. The results showed a remarkable loss in engineering properties of rubberized mortar when ELT rubber was utilized, and the decrease in performance was more pronounced in the samples with zinc-extracted ELT rubber. The pore solution was found to contain significant quantities of zinc and TOC. However, the authors also found that using silica fume to partially replace cement could effectively recover the loss in strength and could reduce the leachability of zinc and TOC.
•A metallurgical processing technique is implemented to leach zinc from end-of-life tire rubber.•The fate of zinc and organic carbon leached from end-of-life tire rubber is studied.•Cement-based materials are proven effective to immobilize zinc and organic carbon leached from tire rubber.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The COVID-19 pandemic has caused a tremendous rise in plastic waste pollution globally. Pollution instigated by plastic has been one of the greatest threats to our world even before the Coronavirus ...outbreak. It is believed that plastic pollution has worsened due to the disposing of millions of personal protective equipment (PPE), such as surgical face masks. The use of plastic waste as a modifier has significantly lowered the temperature susceptibility of pavements, improved asphalt performance, and lowered construction costs, while the recycling of plastic waste has improved the environmental quality and preserved the non-renewable resources. To reduce pandemic-generated wastes and enhance the asphalt rutting resistance, disposable face mask is used as an as an efficient and non-costly modifier to hot mix asphalt (HMA) mixtures. The goal of the thesis is to bring an advancement to the field of transportation infrastructure by evaluating the performance of the flexible pavement using shredded face masks (SFM) as a modifier of HMA mixture and developing a cost estimating calculator to estimate the cost of asphalt pavement construction with mask. Modified HMA mixes with SFM content ranging from 0% to 1.5% were prepared and tested for rutting using Asphalt Pavement Analyzer (APA). It was found that by increasing the SFM content from 0% to 1.5%, the modified samples showed admirable resistance to permanent deformation as rutting depth values decreased from 3.0 mm to 0.93 mm. However, this study has resulted in the improvement of the rutting resistance of hot mix asphalt samples by using shredded face masks (SFM) as a modifier of HMA. Specific contributions include the evaluation of face masks in hot mix asphalt (HMA), and the development of a safe collection procedure for disposable face masks and a cost estimation calculator in Excel to estimate the cost of asphalt pavement construction based with and without face masks. Finally, this research opens a new avenue for the development of sustainable asphalt pavements by reducing pollution and energy consumption and increases knowledge in these areas. The findings of this study provide valuable insights into future efforts by industry and government agencies to develop sustainable approaches for the transportation, energy, and environmental industries. Furthermore, this research could provide a solution to reduce the plastic waste that is polluting the environment due to the COVID-19 pandemic and reveals the scope of a cost-benefit analysis of the process so that economists can assess the socioeconomic benefits of using face masks in pavement construction.
Irrigation is the process of applying appropriate amount of water to crop fields at needed interim. Irrigation is an exigent part of cultivation of rice. Although, the overall yield of rice paddy ...predominantly depends on proper irrigation, irrigation process in developing countries like Bangladesh is still backdated. This study proposes an Arduino/GSM based remotely controlled power efficient smart irrigation system for crops that need to be immersed in water during its growing period. It will ensure the proper irrigation of a field by monitoring water level of the paddy field, providing feedback to farmers and giving farmers option to control the water motor via SMS. This study is expected to improve the overall production of AMAN and BORO rice of Barishal region by automating the traditional irrigation system. Also it will provide a more sophisticated irrigation system for similar types of crops.
The sexual assaults and its consequences are increasing along with socioeconomic development of the country. Rise of modern communication technology add fuel to the flame. This descriptive ...cross-sectional study aimed to evaluate the role of communication technology in sexual assaults in Bangladesh. There were 87 victims included in this study. All were female of 6 years to 40 years of age, mean age was 15.67 (± 6.69) year. Most of the victims were below 20 years of age and came from low income families. About 76% mobile used were smart phone. Among them 46% were owned by the victims herself, 26% gifted by the assailants to the victims. Talking through mobile (37%) was the main communication route between the assailants and the victims; followed by direct verbal (31%), mixed verbal and mobile talking (26%) and others (6%). Regarding methods of communication, they only talk in 42% cases and 36% cases used mixed method (talking, SMS and video chatting). The assailant paid all the costs in 62% cases. Mobile phone came as a blessing in communication, but inchoate use makes it a curse to our society. Parents should be cautious about their children's mobile usage (especially smart phone) daily. Government also should make some policy on using mobile technology by the younger citizens.
CBMJ 2020 July: Vol. 09 No. 02 P: 03-07
PDF
