When hurricanes howl, the greatest danger to people and property is flying debris. Researchers for the Wind Engineering Research Center at Texas Tech University have proof that concrete walls are strong enough to withstand flying debris from hurricanes and tornadoes. According to their findings, homes made of concrete are much more storm-resistant than houses constructed of wood and steel.
To duplicate hurricane-like conditions in
the laboratory, researchers shot wall sections with 15-pound 2 x 4 lumber
"missiles" at up to 100 mph, simulating debris carried in a 250 mph
wind. These conditions cover all but the most severe tornadoes. Hurricane wind
speeds are less than the speeds modeled here. Missile tests designed to
demonstrate damage from hurricanes use a 9-pound missile traveling about 34
mph. Researchers tested 4 x 4-foot sections of concrete block, several types of
insulating concrete forms, steel studs, and wood studs to rate performance in
high winds. The sections were finished as they would be in a completed home:
drywall, fiberglass insulation, plywood sheathing, and exterior finishes of
vinyl siding, clay brick, or stucco.
All the concrete wall systems survived
the tests with no structural damage. Lightweight steel and wood stud walls,
however, offered little or no resistance to the "missile." The 2 x 4
ripped through them.
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