New bridges could last longer

By Ally Phillips, Nebraska News Service
LINCOLN–Many bridges being inspected today were built 50 years ago and are reaching the end of their surface life. But research is underway to build bridges that are expected to last from 75 to 100 years and be just as safe or safer.
Daniel Linzell, University of Nebraska-Lincoln’s civil engineering department chairman, said bridges built in the ’60s were over designed and have therefore lasted as long as they have.
“We’re running out of that buffer or unintentional safety net,” Linzell said. “It’s coming to a point now where we have to make a decision about how important is our bridge and transportation system, and so we want to make an investment as a nation to ensure that it’s functioning.”
Researchers and engineers are using sophisticated computer technology to design and build bridges and are upgrading standard  design codes to improve bridge safety and longevity.  
“There is a lot of work going into improving the process and it’s changing,” Linzell said. “I don’t want to say it’s changing as rapidly as I would like, but it’s changing for the better.”
Materials for bridges are being tested for more durability and longer life spans. Researchers are using computer models to predict bridge behavior, so they’ll know how to respond if there is a problem, according to Linzell.
Mark Traynowicz, Nebraska Department of Roads state engineer, said the state wants to spend more money up front to have longer lasting bridges.
But until then, the roads department is doing what it can to help the current bridges last longer. Traynowicz compared the routine maintenance work on bridges to work homeowners have to do on a house. Repairs on certain parts of a bridge are done before the entire bridge falls apart.
Contact Ally Phillips at nns.aphillips@gmail.com