Wind loads on boundary walls: Full-scale studies

Recent revisions to the wind loading codes for the UK and Australia, and the recent draft European Standard, Eurocode 1, provide new, more onerous, pressure coefficient data for the design of boundary, or free-standing walls. This design information, although obtained from modern wind-tunnel tests, has been called into question by various interested parties. In 1993, a research programme was initiated to undertake an independent, full-scale study of the wind pressures on free-standing walls in order to critically appraise the new data and to determine reliable design data. The full-scale, variable-geometry experimental facility which includes automatic, rapid, data-logging instrumentation is described, and results are presented which show the strong dependencies loads have on wall length, wind direction, position along wall, the presence of a gap, and the presence of return corners. Despite the simplicity of its structural form, the free-standing wall produces surprising aerodynamic effects which have prompted complementary work: reference is made to collaborative research, both model-wind-tunnel testing and computational modelling, which are helping to resolve some of the outstanding questions.