Mean wind pressures on flat roof corners affected by parapets: field and wind tunnel studies

Abstract

This paper describes the experimental data obtained in a full-scale wind-pressure study on a low-rise building, 3.3 m high, located beside a football field on the Loyola Campus of Concordia University in Montreal. Mean wind-induced pressures have been measured on 12 roof corner points for several wind directions. A series of building models were also tested in the boundary layer wind-tunnel of the Centre for Building Studies at three different geometric scales. In particular, the effect of parapets on roof corner local suctions (mean values) has been examined in detail. Both full-scale and wind-tunnel data show that high parapets generally reduce the high suctions on roof corners. On the other hand, low parapets may increase the high values of mean suctions on roof edges and corners. Extensive experimentation has shown that significant suction increases occur only for a particular range of parapet height to building length ratio, namely 0.01< h/ L<0.02. The paper compares the results with those of previous studies on wind loads on flat roofs with and without parapets.