Following the devastation of Hurricane Irma in 2017 and Hurricane Ian in 2022, the Florida Department of Transportation (FDOT) reached out to University of Florida researchers to assess the downed street light poles that were toppled and damaged by high winds. The aluminum poles, which were designed to withstand high wind speeds, unexpectedly failed during these storms. Hurricane Irma damaged 40 light poles in Miami, and Hurricane Ian damaged over 20 poles in Central Florida. Led by UF Civil Engineering Associate Professor Jennifer Bridge, Ph.D., the research group is investigating these failures to improve the durability and safety of light poles against future hurricanes and other extreme wind events.
Downed and damaged light poles can crush vehicles and other utility infrastructure. During hurricane evacuations, fallen poles disrupt traffic and block roadways, hindering evacuees and emergency responders.
“We will conduct wind tunnel testing of scale models of light poles in the NHERI Boundary Layer Wind Tunnel,” Bridge said. The UF wind tunnel is a state-of-the-art facility designed to simulate wind conditions for testing structural behaviors. It is one of seven facilities funded by the National Science Foundation around the nation, commonly called NHERI, an acronym for Natural Hazards Engineering Research Infrastructure. These shared-use facilities enable researchers from all over the U.S. to investigate methods to improve the performance of infrastructure during natural hazards. “These wind tunnel tests will allow us to validate the force coefficients required for design and ultimately determine the capacity these structures need to adequately resist hurricane-force wind loads.”
Bridge is working with Flavia Da Cruz Gallo, Ph.D., a postdoctoral associate in the UF Department of Materials Science & Engineering, to understand the light pole failure modes and analyze how the current material selection and manufacturing processes influence their quality, properties, and reliability. FDOT determines and selects the material used for light poles and other products related to traffic safety, based on standards and specifications, developed by the American Association of State Highway and Transportation Officials and American Society of Civil Engineering. The multidisciplinary team will test small-scale models of light poles to understand how much wind force they can withstand.
“Based on failure analysis and test outcomes, my role is to assess the need for new material selection, new qualification test recommendations or new processing steps for manufacturing, ensuring safety of the road users,” Da Cruz Gallo said.
With that information, the team will be able to provide FDOT with their findings.
Da Cruz Gallo said that the group’s focus is on balancing appropriate improvements with the costs associated with implementing safer and more reliable solutions. The target solution will maintain a functional infrastructure during and after hurricanes, keeping transportation networks operational and facilitating emergency response and recovery efforts.
“Our recommendations will account for a range of wind loading conditions as well as possible deficiencies in the current approaches to the design and manufacture of aluminum light poles,” Bridge added. “As a result, future light pole designs in Florida will be able to perform better, with less susceptibility to wind-induced vibration, crack formation and resultant failure.”
Research began in summer. The team expects to get results by the end of 2025.
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By Reba Liddy
ESSIE Marketing and Communications Specialist