- Eco-friendly concrete and fabric-casting that allows quick, free-flowing designs
- Now you can build a Roman arch with an odd-looking truck
- Spray-on coating makes existing structures stand up to earthquakes
Construction isn’t an industry that likes to take risks. In fact, it’s known for its slow adoption of new technology. That only makes sense – a lot is at stake when you build a bridge or a building, and we want the companies involved in these projects to be certain about what they’re doing. But recent innovations have proven too good to miss, from blockchain-driven smart contracts, to automatic bricklayers, to self-driving construction equipment. And the construction site of the future is already shaping up to be a different place to the ones you might see now.
Some of these inventions are deceptively simple, clever ideas that are rethinking how we get the job done. Some, however, are amazingly high-tech, introducing new materials to solve old problems. Let’s take a look at some of these incredible innovations in construction.
Eco-friendly concrete and fabric-casting that allows quick, free-flowing designs
Concrete is an awesome construction material, which helps to explain why we use so much of it. But it has at least two glaring flaws: it’s terrible for the environment and expensive to cast into unusual shapes.
Producing cement, a major component of concrete, contributes to greenhouse gases, accounting for between 5 and 7 per cent of the world’s emissions. That’s because you need high temperature kilns to bake the raw materials, and their fires are produced by burning fossil fuels. But we just might have found a way to clean up this process. Richard E. Riman, a distinguished professor of materials science and engineering at Rutgers University, has been researching low-temperature reactions that use water as a catalyst. Turning his attention to concrete, he’s re-engineered its composition, and as a result, reduced the needed temps by 30 per cent, yielding a similar reduction in greenhouse gas emissions. Even better, as the concrete cures, it absorbs carbon dioxide from the air around it, decreasing the manufacturing footprint with another 40 per cent. What’s more, this process allows the Solidia concrete, it’s trade name, to cure in 24 hours rather than the usual 28 days. As Riman says, “The first thing we did was show that we could make a material that costs the same as conventional Portland cement. We developed processing technology that allows you to drop the technology right into the conventional world of concrete and cement without having to make major capital expenditures typically encountered when a technology is disruptive to the marketplace”. We expect Solidia to be the go-to material in construction very soon.
But it’s still concrete, and if you want unusual shapes, you need to use hard frames to hold the mixture in place while it cures. To change that design, you need to change the shape of the frame, a time-consuming and expensive process when dealing with custom forms. Ron Culver and Joseph Sarafian, fabric designers at the University of California, have developed a solution. By robotically stretching Lycra sleeves, and then filling them with a mixture of concrete and fibreglass, they can produce fully cured custom shapes in only 45 minutes, reducing waste and allowing a variety of free-flowing designs. These moulded shapes can then be joined together by 3D printers and used as structural elements or supports. Sarafian thinks this might revolutionise the creative use of concrete in architecture. “This casting method has implications at various scales in the construction site of the future. We see it being scaled up to create unique building facade elements or even the primary structure of a building”.
Now you can build a Roman arch with an odd-looking truck
The Roman arch is a fixture of architecture, as it’s very name suggests. Designed to be self-supporting, it uses clever physics, a close fit, and the weight of the construction materials to form a solid shape that doesn’t require mortar. It’s an ingenious solution for supporting heavy loads, but it’s also really complicated to fit properly and anything but safe for the workers constructing it – until now.
The zipper truck is a Roman engineer’s dream come true. Lock-Block, Ltd. uses something like giant Lego blocks, carefully shaped, pre-made concrete blocks that fit together with tremendous precision. Just like Roman materials, these ‘stones’ are designed for a very, very tight fit, allowing them to be self-supporting. But the genius of Lock-Block is the zipper truck, basically just a big truck with an odd addition. Where the cargo would normally be, the zipper truck instead features a conical structure covered in rollers. When you want to begin building your arch, you simply park the truck in the spot and start assembling the blocks on its back. As the truck slowly moves forward, shifting the blocks toward the tighter end of the cone, they slide closer and closer together before automatically falling into place!
It’s pretty incredible to watch:
Lock-block says that using the zipper truck, you can “build a quarter-mile long archway in 24 hours and be immediately functional without a 28 day curing cycle.” That’s a decrease of 90 per cent when compared against the second fastest method – and the blocks are completely reusable!
Spray-on coating makes existing structures stand up to earthquakes
Concrete, even when reinforced with steel, can be shaken apart by the incredible power of an earthquake. Researchers have been looking for ways to improve the strength of our buildings, especially after they’ve been made. The goal, of course, is to be able to retrofit existing concrete structures to improve them, rather than tear them down and start over.
At the University of British Columbia, Nemy Banthia, a world recognised expert in cement and polymers, has developed a radical new approach. Using polymers to reinforce a special concrete, Banthia has produced a sprayable surface that can stand up to earthquakes. It’s called eco-friendly ductile cementitious composite (EDCC), and in recent tests, it made ordinary concrete tough enough to weather a 9.0 to 9.1 magnitude quake. Salman Soleimani-Dashtaki, a PhD candidate who works on the project with Banthia, explained the test. “We sprayed a number of walls with a 10-millimeter thick layer of EDCC, which is sufficient to reinforce most interior walls against seismic shocks. Then we subjected them to Tohoku-level quakes and other types and intensities of earthquakes and we couldn’t break them”.
Now, just imagine the future. We can use less concrete for tunnels and bridges, produce the material in a way that dramatically reduces its impact on the environment, form complex shapes with virtually no waste, and coat everything in an earthquake-proof spray! That’s incredible progress for an industry that’s usually slow to change.