Wind-Induced Internal Pressures of Buildings with Multiple Openings

Based on previous studies, it has been determined that internal pressures can contribute as much (or more) as the external pressures to the net pressures occasioned for low-rise buildings with a single dominant opening. However, the role of internal pressures, as experienced for cases with realistic geometry and multiple openings, is rarely investigated. As is known, low-rise buildings are susceptible to multiple-opening failures during strong windstorms, and the resulting changes in internal pressures are critical measures for tracking how the failure progresses from a localized level to a catastrophic level. Using the Wind Tunnel Laboratory located at Louisiana State University, by testing a typical 5: 12 gable-roof residential-building model with 17 openings, a full picture of the internal pressure changes experienced during progressive failure of multiple openings is obtained. The results indicated that (1) mean internal pressure coefficients estimated by two currently available, public hurricane-loss models were closer to the minimum internal pressure coefficient measurements than the mean internal pressure coefficient measurements at each stage of the multiple-opening failure; (2) ASCE guidelines underestimate the internal pressure for both partially enclosed and enclosed building types; and (3) Helmholtz resonance occurred near the theoretical resonance frequencies for two single opening cases for the current model with high damping. Based on these results, the flow resonance, dependent on the building geometry and the opening layout, should be considered to predict the potential wind-induced damage for low-rise buildings, and this is what is explored in this paper. DOI:10.1061/(ASCE)EM.1943-7889.0000464. (C) 2013 American Society of Civil Engineers.