Civil Engineers Test New Concrete for Stronger, More Durable Bridges
Written on 10:01 AM by Engrmizan
A new kind of concrete called Ductal will allow bridges to hold more weight and last longer. Made of a mixture of sand, cement, water, and small steel fibers, it is 10 times more expensive than traditional materials but also stronger and virtually impermeable, helping bridges become more durable.
AMES, Iowa--Bridges take a beating, and it can really break the bank to repair them. Now, researchers are breaking bridges to learn how to build them better and save you money.
Justin Doornink spends his mornings underneath bridges. He's an engineering student and, as part of his homework, he's installing sensors to measure the impact of traffic on the bridge. He's trying to figure out how to strengthen the structures. One option is ultra-high-performance concrete, which is made from sand, cement, water and small steel fibers.
Brent Phares, a civil engineer and associate director at the Iowa State University Bridge Engineering Center in Ames, says, "It's much, much stronger. It's basically impermeable to water. What those two things mean is you can build a bridge that has a higher capacity and should last a longer period of time."
Brent did a small-scale test with the new concrete, pushing it to its breaking point. It held close to 595,000 pounds -- that's more than seven semi trucks. The material costs 10-times as much as traditional concrete, but you need less of it, and it lasts longer.
"You're never going to advance the state-of-the-art unless you do some research, try some things out, maybe take some risks and see what might ultimately save the taxpayers money," he says.
