Boundary layer wind tunnel simulation of area averaged wind loads

Magnitudes of peak wind load coefficients for components and cladding elements of buildings are reduced as the size of the element increases. Modern building codes include area reduction factors for peak wind load coefficients that are based on limited wind tunnel test results and estimates of lateral coherence. Simultaneous wind pressure records from Wind Engineering Research Field Laboratory (WERFL) at Texas Tech University provide opportunities for evaluating wind tunnel simulations of area averaged wind pressures. Ultimately, studies to determine area reduction factors must deal with three issues. The ability of scale model studies to represent the spatial correlation of full-scale wind pressures, the effect of structural influence functions on the reduction factors and the adequacy of current code provisions. This paper deals with the model simulation issue and presents results of comparisons between area reduction factors obtained from analysis of field and model data. The results demonstrate that appropriate flow simulations can generate distributions of instantaneous pressures on scale models that are in good agreement with results obtained from field measurements.