Post-Charley Evaluation of Undamaged Homes in Punta Gorda Isles

• Main Author: Pierrissaint, Virgilet
• Format: Others
• Published: Scholar Commons 2006
• Subjects: Hurricane; construction; high wind design; proper connectors; inspections; American Studies; Arts and Humanities
• Online Access: http://scholarcommons.usf.edu/etd/3932; http://scholarcommons.usf.edu/cgi/viewcontent.cgi?article=5127&context=etd

Hurricane Charley was the third named storm and the second major hurricane of the 2004 Atlantic hurricane season. At that time, it was also the strongest hurricane to strike the US coast since 1992. Charley made landfall on Friday, August 13, 2004 on the barrier islands off Lee County, Florida whence it moved rapidly inland towards Port Charlotte, DeSoto and Hardee counties. The purpose of this study was to understand the performance of undamaged residential home in Punta Gorda Isles (PGI) in Port Charlotte County that was crossed by Charley’s eye shortly after it made landfall. To achieve this goal, a representative sample of 20 undamaged residential homes (out of 210 identified in an earlier study) in PGI were selected from aerial photographs for detailed analysis. Unfortunately, information on dimensions of these buildings could not be obtained despite repeated attempts over a 6-month period. Consequently, a parametric study was conducted using an idealized building following procedures consistent with current practice. In the analysis, parameters such as wind velocity, exposure and building geometry were varied to assess the range of design forces. The maximum wind velocity was taken as 160 mph, based on findings reported in FEMA 488. Two idealized roof systems – a gable and hip – on a rectangular plan form were analyzed using ASCE 7-98’s Method 2. Both Main Wind Force Resisting System (MWFRS) and Components and Cladding (C&C) were evaluated. The results showed that forces resisted were significantly (over 70%) higher than those designed for. Since 210 out of 425 homes studied earlier were undamaged it suggests that properly constructed structures automatically have adequate reserve capacity to withstand higher-than-designed for lateral loads. If changes are needed, it should focus on inspection and construction rather than wind provisions in existing code.