Note to Editors: Photos are available with the news release at http://newsinfo.colostate.edu.
A Colorado State University engineering professor will conduct a first-of-its-kind study this summer on the force of hurricane-strength waves and their damage to woodframe residential buildings.
John van de Lindt, associate professor of Civil and Environmental Engineering who already studies the effects of earthquakes on multi-story woodframe structures, is collaborating with engineers at Oregon State University at their gymnasium-size tsunami wave tank in the O.H. Hinsdale Wave Research Laboratory.
The wave basin is partially supported by the George E. Brown Jr. Network for Earthquake Engineering Simulation, or NEES, a program of the National Science Foundation, which created a national network of 15 large-scale, experimental sites that feature shake tables, centrifuges that simulate earthquake effects and a tsunami wave basin. Oregon State University is home to the world’s largest experimental facility specifically designed for tsunami research. Its custom-built wavemaker allows it to recreate scaled hurricane waves as well.
A unique aspect of the NEES program is its ability to share data from these experiments with researchers all over the world.
"This is the first real step toward understanding how hurricane-force waves affect woodframe structures," said van de Lindt, the principal investigator on the study, who is working with Rakesh Gupta, associate professor of Wood Science and Engineering at Oregon State University. "We are investigating whether there’s a way structures can be designed so they can survive water storm surge and hurricanes."
"The results of the study, for the first time, will provide information necessary to understanding behavior of residential buildings during storm surge," Gupta said. "This is the first step in making American homes safer during hurricane-induced storm surge in coastal areas."
The University of Hawaii is leading a project to study the effects of larger, more destructive tsunami waves on coastal structures and infrastructure. A small-scale replica of Seaside, Ore., is under construction in the Oregon State University tank to determine how a tsunami – a giant wave caused by seismic activity – affects an entire community.
At Colorado State, van de Lindt’s team of graduate and undergraduate students is busy building numerous one-sixth scale replicas of a two-story, 2,000-square-foot home that can be tested against hurricane waves of various heights and forces in the tsunami tank. Researchers will bring that data back to Fort Collins where they will use hydraulic actuators to simulate hurricane-force waves so they can replicate the wave forces and study physical damage to the homes.
The first test is expected in August.
"To date, there is no standard procedure for measuring the effects of hurricane-force waves on woodframe structures," said Rachel Garcia, one of van de Lindt’s graduate students working on the project. "I’ve learned a lot about construction in this project."
Van de Lindt is no stranger to research into natural disasters – his research at Colorado State has focused largely on earthquakes.
"We can look at hurricanes, too," he said. "It’s not too much of a stretch."
In the wake of Hurricane Katrina in 2005, van de Lindt volunteered to lead a team of engineers from around the country on a study of construction practices in the Gulf Coast region.
The study found that poor construction of older homes in the region contributed to the severity of the damage caused by Katrina’s winds. Gupta, his co-investigator on the wave basin project at Oregon State University, also participated in the Katrina site visits.
Van de Lindt also is the principal investigator on a four-year, $1.24 million NSF study, awarded in 2005, to develop a new design approach for taller woodframe buildings in earthquake-prone areas. The tests are being conducted on very large "shake tables" at Colorado State in Fort Collins, State University of New York at Buffalo and in Miki City, Japan.
The tests, which will culminate in the construction of a 15,000-square-foot, full-scale apartment building in Japan, ultimately could help the woodframe industry safely increase the height of woodframe construction to six or seven stories – from three or four stories – in active seismic zones, van de Lindt said. The shake table in Japan is the largest in the world; researchers using the Colorado State shake table have been testing smaller structures and portions of the structures in preparation for the capstone test in Japan.
NSF estimates more than 75 million U.S. citizens in 39 states live in areas at risk for earthquake devastation. Woodframe structures make up about 90 percent of U.S. building inventory.