Best-built highway bridges no match for fire

DENVER — Colorado Department of Transportation engineers say it’s hard to protect bridges from fires like the destructive one on Atlanta’s Interstate 85 on Thursday.

Colorado’s engineers have been paying close attention to what’s been happening there.

Colorado saw a similar fire in 1985 when two trains collided and burst into flames in Broomfield at U.S. 36 and Church Ranch Boulevard.

The flames were so intense, both highway lanes went crashing down.

CDOT spokesman Bob Wilson said the trains hit head-on beneath the bridge. Two engineers were killed as traffic came to a standstill.

The intense heat generated by the flames sliced through concrete and steel girders.

CDOT chief engineer Josh Laipply said bridges can only take so much heat.

“There’s so many materials out there and so many different things that a fire of a given magnitude in a certain heat, can take down probably about any bridge out there,” he said.

Engineers say, so far, they have not found materials being stored under highways in the state. PVC material that burned underneath the I-85 bridge in Atlanta caused the highway to collapse.

Bridges are inspected every two years for among other things cracking concrete and compromised girders.

Still, drivers are asking questions.

“I drive to deliver and I-70 is cracked up and they like really need to fix all that,” Cornelia Smith said. “It’s not safe and what if it falls or something?”

A fire would only make things worse. CDOT said the busy bridge building season is about to start.

Department representatives will be talking with construction crews and posting warnings about the dangers of storing flammable materials under bridges.

In the meantime, the State Legislature is considering a bill that would ask taxpayers for millions to fix roads and bridges.

But engineers say even some of the best bridges would not be able to withstand a fire like the one in Atlanta.