Modern cities are constantly changing thanks to civil engineers innovating how we build and repair vital infrastructure. Sustainability is also on many people’s minds, including those who plan and execute changes at the civil level. Combined, these two trends in innovation are producing incredible methods for creating sustainable streets and eco-friendly roads across the world.
Today, we’re focusing the spotlight on the bleeding edge of the civil engineering industry. From recycled safety surfacing to self-healing concrete, explore some of the most important ways companies like TSL are using innovative materials to create long-lasting, sustainable roads.
Self-Healing Concrete
First, let’s discuss the cutting-edge technique some companies are experimenting with to create eco-friendly roads: self-healing concrete. While concrete is very strong, it’s also semi-porous, allowing water to flow through the cracks with some ease.
Over time, factors like shifting tectonics, heavy traffic, tension, or even heavy rain can all contribute to concrete roads and pathways forming hairline cracks. Right now, those hairline cracks must be repaired manually, but they’re often left until they become major issues requiring even more extensive maintenance.
But what if that didn’t have to be the case? Self-healing concrete goes through a process called ‘autogenous healing’, where water that passes through the layer of concrete picks up deposits of calcium and carries them to void spaces like cracks or potholes. There, it drops the calcium in a solid form and slowly heals up the imperfection.
While it doesn’t happen instantly, the passage of water and calcium can heal concrete structures without an external repairer getting involved. This whole process requires several special enzymes to be mixed into the concrete, which is why this might also be known by its other name, ‘enzymatic concrete’.
Implementing self-healing concrete can drastically increase the lifespan of concrete roads and reduce the amount of carbon emitted by machines during repairs, not to mention saving cities thousands in repair fees. Although this technique is still emerging, the more cities that see success with its use in eco-friendly roads, the more it will spread into the wider world.
Recycled Plastic
There are so many ways to use recycled plastic, but did you know that one of the most prominent possibilities for recycling could be under your feet?
Asphalt is typically bound by a hot mix called bitumen, which seals all the different particles together and creates a watertight surface for strong roads and pavements. Bitumen uses a lot of virgin plastic, which contributes a lot of carbon to the atmosphere. Luckily, another method is currently emerging.
In 2023, a study by NZTA Waka Kotahi concluded that recycled plastic asphalt mixtures show 150% less cracking and 85% less deformation under pressure testing than many conventional surfaces on the market today. The study prompted a test across ten project sites in Victoria, which alone used 21,000 kilograms of recycled plastic in the asphalt binders.
This incredibly useful solution effectively saves two birds with one Band-Aid by redirecting significant amounts of recyclable waste from landfills and creating high-quality pavement and roads that rival the best on the market.
Another approach is to use recycled plastic in resin-bound safety surfacing. These textured, coloured pavements are the ideal way to encourage motorists and cyclists to slow down and share the road. The more they crop up around urban centres, the more opportunities there are to use recycled plastic instead of virgin plastic.
If this solution is scaled out across New Zealand, the sheer amount of recyclable plastic that could be diverted from landfills will be hard to fathom. That is fantastic news for the world and for Kiwi civil authorities, who need to roll out widespread road repairs on a civil budget.
Enviromesh
Finally, let’s talk about Enviromesh. This is one of the most innovative ways eco-friendly roads are being created in modern-day Auckland, and we’re proud to be the company championing it across a range of applications. The word combines ‘environmental’ and ‘mesh,’ describing an eco-friendly way of using recycled fibres to strengthen or reinforce new concrete roads and pathways.
Concrete can wear out and crack over time, and once water gets into those cracks, the problem gets worse. The role of Enviromesh is to reinforce concrete enough to discourage those cracks in the first place, ensuring pathways and roads last much longer than usual. There are two benefits here:
- Many places use steel to reinforce their concrete right now but manufacturing these steel rods can seriously increase carbon emissions. Fibrous, recycled plastic is just as effective at reinforcing concrete, and it heavily reduces both carbon emissions and the amount of plastic headed to landfills.
- This method is more cost-effective than steel. Civil authorities are more likely to implement this solution across as many roads as possible, ensuring the city’s streets and pathways stay healthy for as long as possible!
Self-healing concrete, recycled plastic bitumen, and Enviromesh are some of the most important ways eco-friendly roads are being built or studied in New Zealand right now, and more are surely on the horizon. With more sustainable roads crisscrossing our urban centres, New Zealand can maintain its position around the world as a leader in sustainability and even clear the way for other cities to follow suit.
To reap the full rewards of these new techniques, cities must have civil engineers they can trust to install and service roads and pavements.
Trust TSL to Build and Maintain Your Eco-Friendly Roads
Finding new and innovative ways to create sustainable streets is a core value for us here at TSL. With many years of experience backing our elite team, we are ready to support any civil advancements on New Zealand’s horizon. Whether you need a new road built or waterblasting services to keep existing roads clean and well-maintained, we’re here to help.
Talk to us about how we can help today.