Wind-Induced Fatigue Loading and Damage to Hip and Gable Roof Claddings

Abstract

Wind-induced fatigue loading and damage to roof claddings on gable-roof and hip-roof buildings are investigated in this study through both wind tunnel tests and computer analyses. The magnitude and distribution of wind pressures on both roofs are first measured at different wind directions. Fatigue characteristics of wind pressures are identified based on a rainflow count method for each tap at its critical wind direction in which its largest negative pressure occurs. Total fatigue loading at each tap on both roofs is then computed using the obtained fatigue characteristics and information on wind climate. Finally, fatigue damage to screw-fastened light-gauge steel roof sheetings of different profiles is estimated in terms of previously obtained S-N curves and a modified Miner's rule. The distributions of fatigue damage index over both roofs show that under the same strong winds, fatigue damage to the hip roof cladding is much less severe than that to the gable roof cladding. For each type of roof configuration, there are considerable differences in fatigue loading and fatigue damage with respect to different locations of pressure taps and different profiles of roof sheetings.