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Variation in chemical property of asphalt immersed in varying aqueous solutions and its leachate property

Wu J, Wang H, Liu Q, Huang Z, Yusoff NIM

Sci Total Environ, 2024 Oct 01;945:174138.
PMID: 38906298 DOI: 10.1016/j.scitotenv.2024.174138

The pavement asphalt properties are susceptible to deterioration under environmental factors, and the deterioration product will affect its surrounding aqueous environment. For this reason, the idealized asphalt-aggregate mixture was treated with coupled temperature, ultraviolet and aqueous solutions based on self-made multifactorial coupled simulation device. Subsequently, the deterioration of asphalt chemical properties was analyzed by fourier transform infrared spectroscopy and saturate-aromatic-resin-asphaltene tests. Meanwhile, the effect of environmental factors on leachate properties was explored based on organic matter contents and chemical elements. Based on that, the grey correlation method was adopted to correlate asphalt chemical properties and leachate properties. The results clearly showed that environmental factors increased the sulfoxide and carbonyl group content of asphalt and transformed the chemical components within it into polar substances. The asphalt chemical properties were gradually improved when coupling ultraviolet with sodium carbonate, sodium chloride and distilled water sequentially. Compared to neutral solution, alkaline solution exacerbated the effect of asphalt precipitates on leachate properties. The environmental factors increased the organic matter contents and chemical elements of leachate with time. The interaction mechanism between asphalt and aqueous environment involved the deterioration of asphalt properties caused by the presence of water, as well as the release of precipitates from aged asphalt into surrounding aqueous environment.
Fulltext Mechanical Performance of Reclaimed Asphalt Pavement Modified with Waste Frying Oil and Crumb Rubber

Bilema M, Aman MY, Hassan NA, Memon ZA, Omar HA, Yusoff NIM, et al.

Materials (Basel), 2021 May 24;14(11).
PMID: 34073812 DOI: 10.3390/ma14112781

Researchers are exploring the utilisation of reclaimed asphalt pavement (RAP) as a recycled material to determine the performance of non-renewable natural aggregates and other road products such as asphalt binder, in the construction and rehabilitation stage of asphalt pavements. The addition of RAP in asphalt mixtures is a complex process and there is a need to understand the design of the asphalt mixture. Some of the problems associated with adding RAP to asphalt mixtures are moisture damage and cracking damage caused by poor adhesion between the aggregates and asphalt binder. There is a need to add rejuvenators to the recycled mixture containing RAP to enhance its performance, excepting the rutting resistance. This study sought to improve asphalt mixture performance and mechanism by adding waste frying oil (WFO) and crumb rubber (CR) to 25 and 40% of the RAP content. Moreover, the utilisation of CR and WFO improved pavement sustainability and rutting performance. In addition, this study prepared five asphalt mixture samples and compared their stiffness, moisture damage and rutting resistance with the virgin asphalt. The results showed enhanced stiffness and rutting resistance of the RAP but lower moisture resistance. The addition of WFO and CR restored the RAP properties and produced rutting resistance, moisture damage and stiffness, which were comparable to the virgin asphalt mixture. All waste and virgin materials produce homogeneous asphalt mixtures, which influence the asphalt mixture performance. The addition of a high amount of WFO and a small amount of CR enhanced pavement sustainability and rutting performance.
Pavement maintenance management framework for flexible roads: a case study of Pakistan

Khahro SH, Memon ZA, Yusoff NIM, Gungat L, Yazid MRM

Environ Sci Pollut Res Int, 2022 Feb;29(7):10771-10781.
PMID: 34613546 DOI: 10.1007/s11356-021-16499-2

Roads play a pivotal role in the overall economic growth of any country. Developed countries allocated sufficient budget to make new roads and to maintain the existing roads. They also have a proper pavement management system (PMS) in practice to manage roads, whereas developing countries suffer from budgetary issues to make new roads and maintain the existing road network. Therefore, this paper explores the awareness of PMS via direct and indirect methods in Pakistan with a proposed framework of the low-cost model and pavement maintenance indicators for developing countries. This paper also performs a scientometric assessment of PMS. A detailed literature review has been carried out for this study, followed by a quantitative study from experienced professionals. The scientometric data is collected from the Scopus database from 1975 to 2020, whereas the data for PMS awareness assessment has been collected using questionnaires from different experts working directly and indirectly in the road management sector. The data has been analyzed using the arithmetic mean because of the nature of the questions and scope of the study. The direct method results show that experts are aware of PMS for a new road, but they have no PMS to rehabilitate roads. The indirect method results show that the authorities are applying various components of PMS, but there is no proper PMS in practice. This paper helps decision-makers to make better decisions and policies for improved road maintenance and rehabilitation. The proposed framework in the study can significantly assist the UN-SDG 9 (Facilitate Sustainable Infrastructure in Developing Countries) and 11 (Affordable and Sustainable Transport System).
Fulltext Effects of Waste Frying Oil and Crumb Rubber on the Characteristics of a Reclaimed Asphalt Pavement Binder

Bilema M, Aman MY, Hassan NA, Al-Saffar Z, Mashaan NS, Memon ZA, et al.

Materials (Basel), 2021 Jun 23;14(13).
PMID: 34201413 DOI: 10.3390/ma14133482

The reclaimed asphalt pavement (RAP) has become a moderately common practice in most countries; Hence, rejuvenating materials with RAP have earned publicity in the asphalt manufacturers, mainly due to the increasing raw material costs. In this study, the crumb rubber (CR) and waste frying oil (WFO) utilized as waste materials to restore the properties and enhance the rutting resistance of the RAP. Several physical, rheological, chemical properties of bituminous binders were tested. The result showed that the RAP bituminous binders incorporating WFO and CR decreased softening points and the increased penetration value; these translate to an increase in penetration index. Moreover, the viscosity of the WFO/CR combination reclaimed asphalt pavement binder showed better workability and stiffness, as well as a low storage stability temperature (less than 2.2 °C) with an acceptable loss upon heating. Without chemical reaction was observed between the waste-frying oil with the rubberized binder and the reclaimed asphalt pavement binder. Additionally, the WFO/CR rheological properties combined with the reclaimed asphalt pavement binder were comparable to the control sample. The incorporation of CR with WFO as a hybrid rejuvenator enhanced the rutting resistance. Therefore, the presence of WFO/CR has a considerable influence on the RAP binder properties while preserving a better environment and reducing pollution by reusing waste materials.
Fulltext A Comparative Review of Hot and Warm Mix Asphalt Technologies from Environmental and Economic Perspectives: Towards a Sustainable Asphalt Pavement

Milad A, Babalghaith AM, Al-Sabaeei AM, Dulaimi A, Ali A, Reddy SS, et al.

Int J Environ Res Public Health, 2022 Nov 11;19(22).
PMID: 36429580 DOI: 10.3390/ijerph192214863

The environmental concerns of global warming and energy consumption are among the most severe issues and challenges facing human beings worldwide. Due to the relatively higher predicted temperatures (150-180 °C), the latest research on pavement energy consumption and carbon dioxide (CO2) emission assessment mentioned contributing to higher environmental burdens such as air pollution and global warming. However, warm-mix asphalt (WMA) was introduced by pavement researchers and the road construction industry instead of hot-mix asphalt (HMA) to reduce these environmental problems. This study aims to provide a comparative overview of WMA and HMA from environmental and economic perspectives in order to highlight the challenges, motivations, and research gaps in using WMA technology compared to HMA. It was discovered that the lower production temperature of WMA could significantly reduce the emissions of gases and fumes and thus reduce global warming. The lower production temperature also provides a healthy work environment and reduces exposure to fumes. Replacing HMA with WMA can reduce production costs because of the 20-75% lower energy consumption in WMA production. It was also released that the reduction in energy consumption is dependent on the fuel type, energy source, material heat capacity, moisture content, and production temperature. Other benefits of using WMA are enhanced asphalt mixture workability and compaction because the additives in WMA reduce asphalt binder viscosity. It also allows for the incorporation of more waste materials, such as reclaimed asphalt pavement (RAP). However, future studies are recommended on the possibility of using renewable, environmentally friendly, and cost-effective materials such as biomaterials as an alternative to conventional WMA-additives for more sustainable and green asphalt pavements.
Fulltext Investigating the Mechanical Properties and Durability of Asphalt Mixture Modified with Epoxidized Natural Rubber (ENR) under Short and Long-Term Aging Conditions

Safaeldeen GI, Al-Mansob RA, Al-Sabaeei AM, Yusoff NIM, Ismail A, Tey WY, et al.

Polymers (Basel), 2022 Nov 04;14(21).
PMID: 36365719 DOI: 10.3390/polym14214726

Modifiers such as fibers, fillers, natural and synthetic polymer extenders, oxidants and anti-oxidants, and anti-stripping agents are added to produce modified asphalt. However, polymers are the most widely utilized modifiers to enhance the function of asphalt mixtures. The objective of this research was to evaluate the mechanical properties and durability of epoxidized natural rubber (ENR)-modified asphalt mix under short- and long-term aging conditions. The physical and rheological characteristics of the base asphalt and ENR-modified asphalt (ENRMA) were tested. In order to evaluate the mechanical properties and durability of the modified mixtures, the resilient modulus of the ENR-asphalt mixtures under unaged, and short- and long-term aging conditions at various temperatures and frequencies was obtained. Furthermore, the resistance to moisture damage of asphalt mixtures was investigated. The findings showed that the stiffness of the ENR-asphalt mixes increased because of the mutual influence of short- and long-term aging on the mixes. In addition, ENR reduced the susceptibility to moisture damage. The stiffness of the mixes was influenced by the temperature and frequencies. By using mathematical modelling via the multivariable power least squares method, it was found that temperature was the dominant factor among all other factors. The results suggested that the durability of asphalt pavements is improved by using ENR.
The quality of life and body image disturbances of Turner syndrome patients in Malaysia: a cross-sectional study

Yusof AAB, Chii MLS, Yusoff NIM, Kama RNIFRM, Raj JR, Ghani NAA, et al.

BMC Womens Health, 2023 Nov 17;23(1):614.
PMID: 37978374 DOI: 10.1186/s12905-023-02745-x

BACKGROUND: Turner Syndrome (TS) is a rare sex chromosome abnormality occurring in 1 in 2500 female live births. To date, there is limited data on TS patients in Malaysia. This study aimed to investigate the quality of life (QoL) and body image disturbances among adult population with TS in comparison to age-matched controls in a tertiary hospital in Kuala Lumpur: Hospital Chancellor Tuanku Mukhriz, Universiti Kebangsaan Malaysia (HCTM, UKM).
METHODS: This was a cross-sectional study carried out in HCTM, UKM, Kuala Lumpur. TS participants who attended clinic in HCTM, UKM and controls who were hospital staff members were recruited via purposive sampling. TS participants' sociodemographic and clinical profiles were retrieved from medical records. Two validated, translated questionnaires; World Health Organization Quality of Life (WHOQOL-BREF) questionnaire and Body Image Disturbances Questionnaires (BIDQ) were completed by participants.
RESULTS: A total of 34 TS patients were approached and 24 (70.5%) of them participated in this study. Their median (IQR) age was 24.0 (7.0) years and their responses were compared to 60 age-matched healthy females as controls [median age (IQR) = 24.0 (8.0) years]. The most common medical problem in TS participants was premature ovarian insufficiency (n = 23; 95.8%). There were no significant differences between TS and control groups' median scores (overall QOL; 4.00 vs. 4.00, general health; 3.50 vs. 4.00, physical health; 14.86 vs. 15.43, psychological health; 14.67 vs. 14.00 and environment; 15.00 vs. 15.50) of the different WHOQOL-BREF domains. However, TS participants were found to score 13.33 against 16.00, lower than the control group (p