Using Clemson expertise on unprecedented project
CLEMSON, S.C.-- Engineers--led by teams from Clemson University--are scrambling to deploy four mobile data-acquisition platforms squarely in the path of oncoming Hurricane Floyd.
The "wind towers" will provide an accurate ground-level picture of the wind speed and direction. Clemson researchers can then use that data to help improve building codes for coastal areas.
"We hope to have our platforms right in the heart of the hurricane when it comes, getting details as they happen, where they're happening," said Scott Schiff, an associate professor in civil engineering at Clemson. Research leader on the projects is Tim Reinhold, also an associate professor of civil engineering at Clemson. Each steel-reinforced platform, which weighs up to 4,500 pounds, is specifically designed to withstand hurricane-force winds and features special securing legs.
The teams--and towers--were initially stationed in South Florida on a project to measure how hurricane-force winds affect houses retrofitted for the storms. That initiative, called the Florida Coastal Monitoring Project, is sponsored by the Florida Department of Community Affairs and includes the University of Florida and Florida International University . But the teams re-deployed the wind towers toward the Carolinas when Floyd continued tracking north.
At rest, each wind tower looks like a giant spider on its back, with legs clutched to its stomach. When fully deployed, the trailer's central tower extends 33 feet into the air while other out-rigger "legs" will extend downward to form a giant X. The points of that X will then literally be screwed into the ground with 2.5-foot earth screws. The platforms can be fully extended and secured in place in as little as 20 minutes.
Most platforms will feature three anemometers specifically designed to operate in high-wind storms. The devices will measure wind speed at heights of 33 feet, a standard reference height, and 15 feet, the height of a typical single-story home. That information will then be relayed along steel-reinforced cables to an onboard computer housed in a reinforced box. The equipment will be powered by generator for the first nine hours, with batteries providing an additional 19 hours of operating time.
The approximately $100,000 project is funded with monies from Clemson University, the Idaho National Engineering Laboratory, the Federal Emergency Management Agency and the Florida Department of Community Affairs.
"This gives us one of our first chances to get the high-resolution wind-speed data - near the ground, close to where a storm passes - that we need in order to develop design bases for hurricane-resistant homes," said James K. Nelson Jr., chair of Clemson's civil engineering department.
Typical airport anemometers simply aren't designed to collect this type of information, said Nelson. Hurricane-hunting aircraft, meanwhile, only measure wind speed at considerable altitude and usually do not make measurements over land.
Clemson's Wind Load Test Facility is one of the nation's top laboratories for testing the effects of wind on low-rise structures such as homes and schools.