As our roads sprawl in a growing network and greater demands are placed on sustainability and lessening our carbon footprint, innovative methods of road construction and materials are coming to the fore.
While innovative construction has environmental benefits, it also minimises cost, maintenance and increases life and quality.
Innovation is not without its obstacles and the main roadblocks to adoption include:
- High costs of technology implementation
- Limitation of funds
- Stakeholders being resistant to change
- Staff and efficiency-related issues
- Time constraints
- Low volume of available work on road innovation
The untrained eye may see nothing more in roads than asphalt and concrete layered uniformly, while in reality they are designed with a variety of products and methods to prevent cracking, ensure longevity and even decrease traffic noise.
There are several notable alternatives to bitumen and traditional roads materials which have emerged in recent years and offer promising potential in redefining not only the design and construction of our roads, but also lifecycle and impact of our primary transport system.
A town in Cumbria has resurfaced a road with a mixture of asphalt and recycled plastic pellets. It’s believed this will last longer than the average road, reducing the carbon footprint of road construction and the price of road repair. The project received an approximate $2 million AUD investment from Richard Branson after the project took out first place in the start-up category of the 2016 Virgin Media Business Voom competition.
2. Bin waste
Scientists from Birmingham’s Aston University have unveiled a bio-bitumen product made from general household waste. When rubbish including plastic, organic materials, paper and textiles is heated to around 500 degrees celsius in the absence of oxygen, it produces a substance with similar consistency and properties to bitumen. This bio-bitumen is yet to be used in definitive trials.
3. Lignin – organic polymer
Lignin is found in the walls of plant cells, giving them shape and integrity, and is a by-product of the paper industry. The first trial of using lignin in conjunction with bitumen was a success. Netherlands employed the new product on a 100m stretch of road regularly used by cars and heavy vehicles in 2015. Ongoing research aims to completely replace bitumen using only a mixture of lignin.
4. Permeable pavement
In the midst of a drought, the significance of pavement which allows rainfall to percolate to a catchment zone can not be lost on Australians. Permeable pavements are an excellent tool in restoring the natural water cycle to urban landscapes and making use of water which otherwise would have been lost as run-off.
5. Fly ash
When the Bay of Bridge of San Francisco was damaged in the earthquake of 1989, its reconstruction in 2002 took advantage of both fly ash and granulated ash from blast furnaces. This both enhanced strength and durability of the concrete and mitigated erosive properties of seawater. Although bitumen only constitutes approximately 5% of the physical road, it makes up over 60% of costs of road construction. Thus, its replacement in this project proved to be enormously cost efficient.
Are you seeking innovative methods of ensuring road longevity while decreasing costs?
The Road Engineering and Maintenance conference, being held in Sydney from 28 – 29 April, explores innovatives in road engineering and maintenance technologies, including asset management and use of alternative materials. The conference also shares strategies to drive efficiency in maintenance processes to extend the asset lifecycle, methods of leveraging data driven decision making and best practice in risk assessment and future-proofing of roads.