New research promises speedy bridge repair after quake
Salt Lake City — (KUTV) Utah has been preparing for a major earthquake for years, with several buildings and bridges retrofitted to withstand a 6.0 quake.
But if that quake hits the Wasatch Front as officials have been expecting, many roads and bridges could be blocked off because of damage.
That's why University of Utah civil engineering professor Chris Pantelides has developed a new technique for repairing needed bridges within a matter of days, to allow emergency services to get help those in need.
Pantelides, who has helped retrofit several major bridges in Utah, started looking for a way to repair those smaller bridges that haven't had any prevention work completed, but would be badly damaged in an earthquake.
Alongside other researchers, Pantelides started by damaging bridge columns in a warehouse lab on campus to imitate the damage caused by a major earthquake.
"The damage would be about the same. You would see concrete crashing and falling off, and you would see bars yielding," Pantelides explained.
Repairing a bridge with that much damage could take up to a month, and in the case of an emergency where people need to get through the city, that's a long time to wait.
"We decided to repair it like after an earthquake fast, and the key here is very fast," Pantelides said.
Researchers drill a steel rebar into the column, then pour concrete around the column and wrap the base with carbon fiber, which is stronger than concrete.
"It's stronger because it has textile properties stronger than concrete. For example, it's 1 1/2 times as strong as steel," he said. "It would usually take more than a month (to repair a bridge) and we can do it in less than a week."
It can take a few days, in fact. And that's important for crews after a major disaster.
"We know that in the 9 counties around Salt Lake, there are roughly 1800 bridges," said Joe Dougherty, spokesman for the Utah Division of Emergency Management. "A damaging earthquake means interruptions to roads, to utilities, to all sorts of things we depend on every day."
Pantelides says his research can help repair those bridges quickly, and the repairs will last for years, even if an aftershock hits and threatens more damage.
"With this (repair), we are able to withstand another earthquake," he said.
The study was published in the American Concrete Institute Structural Journal.
