Wind Speed‐Damage Correlation in Hurricane Frederic

Abstract

Hurricane Frederic of 1979 caused wind damage to buildings, power lines, and trees in the coastal areas of Alabama, Florida, and Mississippi. Wind speeds were recorded in Hurricane Frederic at sufficient number of stations to establish maximum ground level wind speed regimes in affected communities. The established wind speeds are fastest‐mile wind speeds at 10 m height in flat, open terrain. Thus, established values are similar in character to those employed in building codes. Evaluations of the performance of buildings reveal that fully engineered buildings performed well, even when wind speeds were sligritly above code specified values. One common damaging mode was breakage of glass windows by windborne debris. There was significant structural damage to pre‐engineered and marginally engineered buildings, including some frame collapses in wind regimes corresponding to or slightly in excess of code specified values. Damage to these types of buildings was attributed to “weak links” and was influenced by limited redundancies common to other building types. Residences performed satisfactorily from a life‐safety point of view, but sustained extensive economic losses.