It’s the stuff of modern life, and we use it in astonishing quantities. Last year, around the world, nearly two billion tons of steel was produced — more than 500 pounds for every person on earth. And at least 30 billion tons of concrete, or nearly 9,000 pounds for each of us. The scale can be hard to believe, until you look at a runway or a suspension bridge and contemplate what was required to build it.
Apart from developing blended cements, researchers and companies are focusing on ways to use captured CO2 as an ingredient in the concrete itself, locking it away and preventing it from entering the atmosphere. CO2 can be added in the form of aggregates — or injected during mixing. Carbonation curing, also known as CO2 curing, can also be used after concrete has been cast.
Start-ups are vying to enhance the lives of those living with mobility challenges by adding artificial intelligence to wheelchairs. The thought is that computer vision and intelligent braking tools can make the devices safer and easier to operate. A few firms are gaining traction, so wheelchairs of the future may be able to do more than move people from one place to another.
You may have come across the detectable warnings on sidewalk ramps before crossing the street. They're called truncated domes, which are surface indicators designed to assist those who are visually impaired, like Rachel Fisher.