Mapping the Future: How UAE Roads Will Withstand Climate Change and Heavy Traffic
Roads in the UAE face extreme conditions, with high temperatures and heavy traffic putting stress on asphalt surfaces. Temperatures above 40°C can make roads significantly hotter, which increases the risk of softening and permanent damage to the asphalt. Research is being conducted to ensure UAE roads are resilient enough to handle these conditions and the even harsher temperatures expected due to climate change.
A team of scientists, led by Dr. Waleed Zeiada from the University of Sharjah, has developed a “billion-dirham map” that identifies the ideal asphalt binder grades for different areas of the country. The map aims to save the government money by improving the durability of roads and reducing the need for maintenance and repairs in the future. “This map is worth a billion dirhams because this will save maintenance and rehabilitation money soon,” said Dr. Zeiada according to The National Magazine.
Asphalt binder is the key component that holds the road’s aggregate together. Different grades of binders are necessary depending on temperature and traffic conditions. Harder binders are better for high temperatures and heavy traffic but can crack at cooler temperatures, while softer binders are more prone to deformation in heat. Traditional grading systems focus on factors like softening point and penetration value, but “climate change and the high temperatures it brings, along with large traffic volumes, mean that traditional binders sometimes ‘cannot meet the requirements of use’,” noted Dr. Haopeng Wang, a researcher involved in the study.
To address this, additives like “crumb rubber” from old tires are being used to improve the elasticity and flexibility of asphalt, making it more resistant to cracking and deformation. Additionally, researchers are exploring the use of bio-based materials like lignin, a component of plant cell walls, to improve binder performance.
The research also looked at the suitability of the previous asphalt specification, which was found to be appropriate for only about 1% of the UAE’s area. Their new map identifies 12 different asphalt specifications, based on a “Superpave” grading system from the U.S., for various regions in the UAE. “This selection process should consider the specific climate conditions in the UAE,” they wrote, ensuring optimal performance against rutting and cracking.
For most of the UAE, the 76-10 grade is recommended, capable of withstanding temperatures up to 76°C. In regions with slightly lower temperatures, the 70-10 grade is suggested. Roads with higher traffic volumes, such as highways, require stronger binder grades, like the “E” form for extremely heavy traffic on roads like Sheikh Zayed Road.
Dr. Zeiada and his team are also planning for future scenarios, looking at asphalt mixtures needed in the UAE through 2050 and 2080 based on various carbon emissions scenarios. They are particularly interested in recycling plastic into asphalt mixtures, which would reduce waste while improving the road surface’s ability to handle extreme conditions.
This research underscores the complexity of designing road infrastructure that can withstand the UAE’s harsh climate. “A lot of people take our roads for granted. They think it’s a very simple construction, but it has a huge influence on our everyday lives,” said Dr. Wang, emphasizing the importance of these materials for long-term sustainability.
(Photo from WAM)
