Clemson Rips Apart Houses For Science

Using everything from high-tech crowbars to a 35-ton crane, Clemson civil engineers will “test to destruction” houses outfitted with hurricane-resistant retrofits. Test subjects range from brick ranch to wooden two-story; all were damaged by floods in Hurricane Floyd and slated for destruction in Horry County.

“This takes the lab into absolute real-world conditions where we can scientifically monitor exactly what happens and evaluate how well the retrofits work," said Tim Reinhold, Clemson associate civil engineering professor. Reinhold and his team of five students are making side-by-side comparisons of retrofitted and non-retrofitted areas to determine what works best and can be installed most easily by contractors in the field.

Work started earlier this summer, but the most visual blowdown will be Tuesday, Aug. 14, when a two-story home takes a tumble for science. A crane will pull apart roof and wall segments to demonstrate the differences in strength that can be achieved by using different construction details and procedures. Engineering standbys, such as vacuum chambers and pressure transducers, will be used, but researchers will also expand the scientific arsenal to include airbags exploding against windows and air-borne debris (ie, 2x4’s) pounding walls, shutters and saferooms at speeds of 100 mph. Additional homes may be tested in late September.

The project is a partnership between Clemson, Horry County, the South Carolina Department of Insurance, the Institute for Business & Home Safety (IBHS), the Horry-Georgetown Homebuilders Association and local building officials from Horry County, Conway and Myrtle Beach.

Retrofits under study include the effectiveness of adding screws or ring-shank nails as a supplement to the existing nailing pattern on news roofs; using adhesives applied from the attic space on existing roofs; bracing gable roof ends to prevent the failure; installing hurricane straps or retrofit brackets to strengthen the roof-wall connection; using structural ties to improve anchorage of porch roofs or substantial overhangs.

Results of the tests will be compiled by Thanksgiving. Clemson has one of the nation's top research facilities to study and mediate the effects of high winds on low-rise structures such as homes and schools.

The nearly $84,000 project will provide more accurate estimates of retrofit costs and the potential benefits of such measures, said Jeff Sciaudone, associate director of engineering for the Institute for Business & Home Safety. The IBHS is an initiative of the insurance industry to reduce deaths, injuries, property damage, economic losses and human suffering caused by natural disasters.

"This information is essential for homeowners wanting to determine whether the expense and disruption of the remedial measures are worth the investment,” said Sciaudone. For Horry County, hurt by Hurricane Floyd in September 1999, the project is an opportunity to take back a little of what Floyd took away.

"The county lost millions of dollars. But projects like this will help make us better prepared for the next hurricane," said Paul Whitten, director of public safety for Horry County. The test homes are among the 29 homes bought as part of FEMA's repetitive flood buyout program in Horry County. The retrofitting and testing will take place this summer. The land must be returned to an open, undeveloped state in the fall of 2001 to meet the requirements of the FEMA buyout program.