Current national bridge maintenance strategies favor replacement over maintenance. A fairly simple amortization formula is used, resulting in overly conservative estimates of the long-term health of a bridge. In a study published in the American Society of Civil Engineers’ Performance log of built facilities, researchers from the College of Engineering at UGA are proposing a new model for the first time. This new approach takes into account the interaction of 60 to 80 bridge components to predict the long-term performance of the bridge and focuses on maintenance rather than replacement.
“Rather than viewing a bridge as a monolithic structure, the Coactive Bridge Model assesses a bridge as a system in which changes in the state of each coactive element not only directly affect the overall performance of the bridge, but indirectly influence performance. other dependent elements, ”said Brian Oyegbile, one of the study’s authors.
Oyegbile obtained his doctorate. in Engineering from UGA in 2020 and now working with the California Department of Transportation.
As an example, Oyegbile claims that replacing a damaged bridge expansion joint is inexpensive and has a marginal impact on overall bridge performance in the short term. However, salt from defrost or contaminated water can seep through a damaged expansion joint over time, accelerating deterioration of more critical items below, such as a column. Likewise, a bridge deck can deteriorate more quickly when debris builds up in an expansion joint and restricts the normal expansion and contraction of the deck.
Proactive component replacement at the right time – even something as small as an expansion joint – can have a big impact on the health of the bridge in the long run, according to UGA researchers. They say their model can provide stronger data and more accurate depreciation forecasts for state transportation agencies planning bridge maintenance, repair and replacement. Nationally, bridges last an average of 75 years. With rapid and efficient application of available resources, researchers say these bridges can serve for over 100 years.
“To me, the co-activity is evident in the bridge inspection data and we can scientifically leverage the data analysis in bridge life predictions, saving money for maintenance and repair. building the country’s infrastructure, ”Oyegbile said.
Regular maintenance would save money
Stephan Durham, a professor at the College of Engineering and one of the study’s co-authors, says your home’s heating and cooling system is a good analogy.
“Like clockwork, I replace my air filters every two months whether the system has been heavily used or not, because it keeps the system running efficiently,” he said. “It’s the same with a bridge. If you regularly replace an expansion joint, whether it’s completely worn out or not, your bridge will perform better than if you allowed it to degrade to the point that a component absolutely needs to be put back, replaced. “
The researchers analyzed data from the Federal Highway Administration’s national bridge inventory for Alabama, Florida, and Georgia to build and test their model. Georgia alone has over 15,000 bridges. The IBN database includes inspection reports on individual bridge elements, proving a wealth of information for researchers.
“Before our work, we had not seen a mathematical model that took into account the interaction between the elements of the bridge,” said Mi Geum Chorzepa, associate professor and principal investigator of the study. “We need a more realistic way to assess the condition of bridges and prioritize preventive maintenance, especially in such a difficult budgetary environment.”
Researchers estimate that an investment of $ 10 billion in timely and appropriate preventive maintenance on the country’s bridges over three years would generate $ 20 billion in recurring savings by 2024. These savings could be spent elsewhere, such as building new infrastructure, and would help spur economic growth, according to the team.
The Georgia Department of Transportation, which funded the study, recently approved a grant for the researchers to expand their work. In the second phase of the project, the team will work with the GDOT Transport Data, Bridge Research and Maintenance offices to develop a bridge life cycle assessment tool for use by GDOT and the state county governments.
The research team also includes S. Sonny Kim, associate professor in the College of Engineering.
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Material provided by University of Georgia. Original written by Mike Wooten. Note: Content can be changed for style and length.