Bridge Work

Top FHWA bridge engineer looks at today’s and tomorrow’s bridges.

By John Latta

America’s bridges are safe.

T hat’s the core message in an overview of those bridges from Tom Everett, P.E., the Federal Highway Administration’s principal bridge engineer and bridge programs team leader.

“There are thousands of qualified bridge inspectors out there working to make sure bridges are safe for public travel and evaluating those bridges,” says Everett. “If a bridge is deemed unsafe, they take prompt action – they close it, divert traffic or whatever. We do not have a national bridge safety crisis on our hands. [People] don’t need to be afraid to drive across a bridge to work or as the kids go to school. We have a lot of people working every day to ensure that.”

Tom Everett

And this won’t change, he says. “I think you’ll see FHWA step up our oversight of the bridge inspection process.”

What’s more, he says, in terms of bridge conditions, the state of America’s bridges has shown a positive (downward) trend in reducing the total number of deficient bridges.

Of the challenges facing bridge owners, Everett, not surprisingly, says, the single biggest one is probably establishing a sustained funding source to adequately address the bridge needs. While we wait, he says, “we must maximize the use of the funding available to maintain our good bridges in good condition and, at the same time, reduce the population of deficient bridges with rehabilitation and replacement.”

Other significant challenges, he says, include: the increased deck areas of America’s bridges, which means more to maintain, preserve and inspect, increasing construction costs, and increasing traffic volume (by both volume and weight); dwindling resources for owners; and the need to “invest adequately in preserving existing bridges, and doing so systematically. This is one of the best ways to reduce the rate of deterioration.”

Changes have come in recent years in the way FHWA deals with bridges, and they will continue to come, says Everett.

“We must continue to learn from the deterioration mechanisms of our existing bridge population and design our future bridges to eliminate these deterioration mechanisms. The Long-Term Bridge Performance Program (see sidebar) will help us in this regard. Accelerated bridge construction and prefabricated bridge elements and systems (PBES) will have major impacts on how we build, inspect and maintain our bridges. High-performance materials will enhance the performance of prefabricated bridge elements.”

By placing greater emphasis on systematic preventive maintenance and system preservation, states can maintain existing bridges in good condition and minimize deterioration of bridge elements while addressing the deficient bridges, he says.

Funding uncertainty has created a need for greater emphasis on lifecycle cost analysis when bridges are rehabilitated or replaced to find the most cost-effective strategy, according to Everett, and business practices may need to change to evaluate the impact on the user and consider this in the project development process.