Wind flow characteristics and their loading effects on flat roofs of low-rise buildings

Abstract

Wind flow and pressure on the roof of the Texas Tech Experimental Building are studied alongrnwith the incident wind in an effort to understand the wind-structure interaction and the mechanisms of roofrnpressure generation. Two distinct flow phenomena, cornering vortices and separation bubble, are investigated. Itrnis found for the cornering vortices that the incident wind angle that favors formation of strong vortices isrnbounded in a range of approximately 50 degrees symmetrical about the roof-corner bisector. Peak pressures onrnthe roof corner are produced by wind gusts approaching at wind angles conducive to strong vortex formation. Arnsimple analytical model is established to predict fluctuating pressure coefficients on the leading roof corner fromrnthe knowledge of the mean pressure coefficients and the incident wind. For the separation bubble situation, thernmean structure of the separation bubble is established. The role of incident wind turbulence in pressure-generationrnmechanisms for the two flow phenomena is better understood.