Guidelines for the calculation of wind speed-ups in complex terrain

Several wind loading codes of practice make use of simple guidelines to assess the effect of topography on design wind speeds. These guidelines generally use some measure of the hill slope to predict the speed-up, and are normally derived by considering an isolated hill. In practice, hills are unlikely to be isolated and the effects of the surrounding topography must be included. This paper considers the results of a wind tunnel study of boundary layer flow over a number of two-dimensional complex surfaces. The effect of upstream topography is quantified and the observed speed-ups are compared to those predicted by the current Canadian and UK codes of practice. Comparison is also made with speed-up values calculated by using a linear model of flow over topography. (C) 1998 Elsevier Science Ltd. All rights reserved.