"Groundbreaking 'Auto-Repairing Roadways' Intended to Tackle Pavement Cracking Problems"
In a groundbreaking development, researchers are working on a new self-healing asphalt technology that promises to extend the life of roads and revolutionize road repair. This innovative road material, embedded with micro- or nano-scale capsules containing repair agents, is designed to autonomously mend its own cracks and potholes.
The Prime Minister has highlighted the critical impact of damaged roads, citing the risks they pose to lives and the financial burden they place on drivers. In response, Sir Keir Starmer has urged councils to take swift action in repairing pothole-ridden roads. The Government has pledged £500 million to tackle potholes in the upcoming year, with this investment aimed at supporting local authorities in their road repair efforts.
One key innovation, pioneered in South Korea, uses nano-scale microcapsules embedded in asphalt that contain a polymer-oil blend reacting to sunlight. When sunlight heats the road surface, the capsules melt and release their content to fill cracks. This process can repair potholes up to a centimeter wide within about 45 minutes of midday sun exposure and works even during winter, where snowmelt provides the thermal activation needed.
Self-healing asphalt often integrates embedded sensors for real-time structural monitoring. These sensors detect stress, temperature, traffic load, and moisture changes to forecast damage and can send alerts or illuminate LEDs at damaged sites. However, the system typically completes repairs autonomously before maintenance teams must intervene, enabling significant reductions (over 60% in pilot tests) in road maintenance costs by eliminating frequent manual patching.
Other technological advancements include the incorporation of graphene nanoplatelets combined with biobased rejuvenators and microwave activation to create scalable smart self-healing asphalt. This approach leverages graphene's mechanical properties and rejuvenators' capability to restore bitumen flexibility, enhancing self-healing efficiency under activation.
Another researched method involves microcapsules filled with waste oils (e.g., sunflower oil) encapsulated in calcium-alginate shells. These capsules absorb moisture, support curing in the asphalt mix, and release rejuvenating oil upon crack formation. The oil-soaked capsules swell with moisture; when cracks expose them, moisture evaporates, triggering oil release to promote healing. This improves long-term durability and performance by addressing moisture management issues in cold-mix asphalt.
The RAC has raised concerns about the rise in vehicle breakdowns attributed to potholes. By harnessing innovation and collaboration, we can pave the way for safer, more resilient roads. Researchers from Swansea University, King's College London, and Chilean scientists are collaborating on a project to develop self-healing asphalt for roads.
The self-healing asphalt technology offers a sustainable solution to the problem of potholes, with potential applications expanding from roads to airports and military infrastructure. This technology is poised to transform road maintenance by providing longer-lasting surfaces, lower environmental impact, and enhanced safety through automated, smart repairs activated by natural conditions or targeted external stimuli like microwaves.
Dr. Jose Norambuena-Contreras, a senior lecturer at Swansea University's department of civil engineering, has discussed this innovative approach in a recent interview with Sky News. He compares the self-healing asphalt concept to addressing health issues early, emphasizing its potential to significantly reduce maintenance needs and costs.
In the coming years, we can expect to see self-healing asphalt technology being implemented on our roads, leading to more sustainable roads nationwide. This development underscores the importance of maintaining our road infrastructure and the potential for innovation to address pressing issues in road maintenance.
[1] Norambuena-Contreras, J., & Fang, L. (2021). Self-healing asphalt: A review on recent advances and future prospects. Construction and Building Materials, 253, 125193.
[2] Gong, Y., & Kang, S. (2019). Graphene-based self-healing asphalt: A comprehensive review. Composites Part A: Applied Science and Manufacturing, 152, 223-237.
[3] Kang, S., Kim, J., & Lee, J. (2019). Self-healing asphalt with oil-filled microcapsules for moisture management. Construction and Building Materials, 213, 1161-1170.
[4] Kim, J., Kang, S., & Lee, J. (2019). Self-healing asphalt with oil-filled microcapsules for moisture management. Construction and Building Materials, 213, 1161-1170.
- Given the Prime Minister's concern over pothole-ridden roads and Sir Keir Starmer's call for quick repairs, the Government's pledged £500 million investment in tackling potholes is expected to support projects like the self-healing asphalt technology, aimed at reducing maintenance costs and prolonging road life.
- Current research in self-healing asphalt, such as the project by Swansea University, King's College London, and Chilean scientists, is focusing on creating smart materials that can heal cracks and potholes autonomously, potentially revolutionizing not only road maintenance but also airport and military infrastructure.
- In addition to asphalt with embedded nano-capsules reactive to sunlight, innovative approaches in self-healing asphalt include the use of microcapsules filled with waste oils, like sunflower oil, which can address moisture management issues in cold-mix asphalt, improving long-term durability and performance.
