Engineers from Rensselaer Polytechnic Institute will be studying small-scale models of sections of New Orleans' flood-protection system using a 200-g centrifuge.
The researchers will replicate conditions during Hurricane Katrina by subjecting models to flood loads.
Rensselaer's centrifuge has a large arm that swings model structures around at 250 mph, exerting forces real structures would face only at catastrophic moments.
"Suppose we want to test a levee that is 100-ft high," says Tarek Abdoun, principal investigator and associate professor civil and environmental engineering. "We can build a model that is only 1-ft high and then spin it around at 100 g, making it equivalent to a 100-ft-high levee."
A system of sensors measures the response of levees in both vertical and horizontal planes, and cameras mounted around the models make visual observations.
Researchers will build and test models of typical levee sections from several locations in New Orleans, including the 17th Street Canal and the London Avenue Canal.
At the 17th Street Canal, for example, the foundation is a complex combination of peat and weak clays, which may have caused that levee's failure, says Thomas Zimmie, professor and acting chair of civil and environmental engineering. Likewise at the London Avenue Canal, a section of fine sand under the levee might have been the culprit. "The information we collect will provide hard data, helping us better understand how levees respond under extreme conditions," explains Zimmie.