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l INTRODUCTION AND SUMMARY On Monday, March 26, l984, a low-pressure system formed in West Texas. As it crossed the Midwest it increased in strength. The hot, dry air from the southwest gathered moisture from the Gulf of Mexico and met with cold dry air from the interior of the continent, creating an unstable air mass. By the morning of Wednesday, March 28, heavy rain and strong winds were being experienced in Georgia. By the time the storm reached South Carolina, conditions were ideal for the creation of tornadoes. The National Severe Storms Forecast Center of the National Weather Service issued its first tornado watch at 2:l5 p.m. Record low pressures were recorded as the storm passed, accompanied by severe thunderstorms, heavy rain, and hail. The first tornado was reported by a South Carolina state trooper near Ware Shoals, about 20 miles from the Georgia border, at 4:35 p.m. The Columbia office of the National Weather Service issued a tornado warning at 4:45 p.m. Between 4:35 p.m. and l0:50 p.m. the storm trav- eled northeast across South Carolina and North Carolina, killing at least 57 people, injuring approximately l,300, causing over $200 million of damage, and leaving more than 3,000 people homeless. Figure l shows the track and intensity of each tornado as identified from an aerial survey by T. Theodore Fujita and his colleagues at the University of Chicago (National Oceanic and Atmospheric Administration, l984). The intensities reported in the survey ranged from Fl (moderate damage) to F4 (devastating damage) on the Fujita damage scale. Path lengths varied from l to 45 miles, and the mean path width from 0.l to l.5 miles. The longest tornado (the McColl tornado) was also the widest, with a maximum width of 2.5 miles. Although no more tornadoes were reported after the storm left North Carolina, strong winds and heavy rain or snow occurred along the Atlan- tic Coast into New England. Further details of the storm can be found in the report produced by the National Oceanic and Atmospheric Admini- stration (l984). This report discusses the damage observed in three locations in South Carolina: Newberry in Newberry County, Winnsboro in Fairfield County, and Bennettsville in Marlboro County. Although damage occurred in other parts of the state, these three locations accounted for the majority of the damage in South Carolina. They also exhibited damage to the greatest variety of buildings. The damage discussed in this report was inspected on March 29 and 30.
In Newberry the tornado literally ran along Main Street, damaging buildings that ranged from modern commercial buildings to churches and assembly buildings over l00 years old. In Winnsboro the tornado followed an arc around the town, striking domestic housing, steel-framed commercial and government buildings, a private school, a church, and several mobile homes. In Bennettsville the tornado also skirted the town, severely damag- ing a shopping center, apartment complexes, and a variety of domestic dwellings. The Newberry tornado was classified by Fujita as F2 and the Winns- boro and Bennettsville tornadoes as F4 (see Figure l). On the Fujita scale an F2 tornado is associated with wind speeds of ll3-l57 mph and an F4 tornado is associated with speeds of 207-260 mph. An engineering analysis of one of the structures and comparison of the damage with that caused to other structures by hurricanes with known wind speeds sug- gested that, although the damage descriptions were appropriate, the wind speeds were probably much lower, perhaps less than l50 mph. Fujita also reported that the mean path width of these tornadoes was large: 0.6 mile in the case of the first two, and l.2 miles at Ben- nettsville. The wind speed within these tornadoes would therefore have varied considerably. As a consequence, this report discusses damage by type of building rather than by location. As expected, mobile homes performed very poorly in the tornadoes, with nearly 40 percent of the storm-related deaths occurring in these structures. In some cases, mobile homes were completely destroyed while adjacent structures were virtually undamaged. The performance of domes- tic dwellings varied considerably depending on location and quality of construction. Public buildings constructed of unreinforced load-bearing masonry suffered extensive damage. Steel-framed public buildings per- formed much better, although cladding and secondary members were often severely damaged. A particularly disturbing failure was that of the Northwood Village Shopping Center in Bennettsville, which had a hybrid steel and masonry form of construction similar to that of hundreds of shopping centers in the region. For wood-framed buildings, some simple improvements in construction techniques, such as securing rafters or roof trusses to the frames and the frames to the foundation, could significantly reduce the risk of collapse and loss of life in future severe storms. Good roof ties and the provision of vertical reinforcement in walls could have a similar effect for masonry structures. There is no state-wide building code in South Carolina. If a juris- diction adopts a building code, it must be one approved by the state, which currently means the Standard Building Code (Southern Building Code Congress International, l982). However, most rural areas have not adopted a building code, and even when a code has been adopted, inade- quate resources often limit its enforcement. This has had an adverse effect on the quality of construction in general and on the ability of structures to resist the natural hazards of tornadoes, hurricanes, and earthquakes to which the area is prone in particular. The state-wide enforcement of appropriate building regulations could greatly reduce damage and loss of life in future events of this type.
