Would You Trust a Bridge Made Entirely of Rubbish?
When Dr Thomas Nosker was a graduate student at Rusker University in the 80s, the school was awarded a government grant to develop recycling systems for the ever-growing plastic bottle industry. After a great deal of experimentation, Nosker created a composite polymer made of no. 2 plastics and polystyrene plastics (car bumpers and dashboards).
Fast forward to today, and Axion Construction is still using this polymer in railroad ties and bridges. Axion is also using it to build cost-effective pre-made products, like its Struxure bridges. They are an 80:20 mix of no. 2 plastic and polystyrene, and are immensely strong and weather-resistant.
Axion’s clients include Logan County, Ohio, which used Struxure to create its Onion Ditch Bridge. The decision to use Axion’s product was easy, as the community is working hard to reach its goal of becoming a zero waste county by 2020.
The bridge is approximately 7.5m; its the longest of its kind and is completely resistant to insect infestation, rust, and moisture. Other great advantages are that paint won’t stick to the plastic, which means graffiti isn’t a problem, and it won’t crack from long-term exposure to direct sunlight.
Way back when …
Axion claims that since the first vehicle access bridge made out of this material was built at a Missouri military base in the early 90s, they have never had to replace any parts or repair the bridge in any way. The same goes for the Struxure bridge built in New Jersey’s Wharton State Forest.
These bridges, particularly the one in Missouri, have been known to carry loads of over 70 tons. A bonus for the construction budget is that the materials require no special machinery to install, and they leave little mess behind, as the whole thing is constructed off-site. Furthermore, the lifespan of a Struxture bridge is estimated at 150 years, with zero maintenance.
In the USA, the spotlight has been on wood and steel structures that have fallen into such bad disrepair that they would require massive reconstruction or total replacement at a cost of billions of dollars.
The issue became a high priority when a bridge on Washington State’s Interstate 5 collapsed after a 10 ton truck carrying drilling equipment bumped into the steel structure. Fortunately, no one was hurt in the accident, but the results could have been devastating.
And the money?
A large portion (80%) of the funds for the Onion Ditch Bridge came from the Federal Innovative Bridge Research and Deployment Program. To ensure that the project came within budget, Axion had to take great care to include all design, parts and labour into the cost estimate. Axion also had to ensure that the design suited the aesthetics and character of the community.
The eventual cost was approximately $250 000; far cheaper than the construction of a conventional bridge.
And the future?
The future of construction will hopefully involve the use of 100% recyclable materials, such as those that currently fill our landfills. A good place to start is by replacing the old and potentially dangerous structures (like the bridge on Interstate 5) using materials like Struxure.
Not only will bridges like these help minimise the construction industry’s carbon footprint, but they could also save lives. The weathering effects on old bridges were painfully evident during Hurricane Katrina and Hurricane Sandy, as many people lost their lives trying to cross bridges that collapsed during the disaster.
History is full of examples of buildings constructed from natural materials. It’s time we started seriously follow those examples, as well as the examples of places like Thailand’s Wat Pa Maha Chedi Kaew temple, which was built with more than a million glass bottles.
Tracey Walker, like many of us, is concerned about the state of the planet and applauds any and all efforts to put right centuries of wrongs.
- 100% Recycled Plastic Bridge Holds Strong In Ohio (earthtechling.com)
- USA’s Longest Bridge Built from Recycled Material Opens (jugraphia.wordpress.com)
- Day 20 (cleanourcreeks.wordpress.com)