Correlation and combination of wind force components and responses

This paper summarizes the findings from extensive wind tunnel tests carried out by the authorsʹ group for the evaluation of wind load combination effects for various types of building models. Characteristics of correlations of wind force components are examined using the absolute ratio of wind forces, phase–plane trajectories and (absolute) cross-correlation, and then wind load combinations are examined. The necessity to consider wind load combinations is inferred from the instantaneous pressure distributions, and the cross-correlation coefficients of the absolute values of wind force components are found to be more important when examining wind force combinations. Wind load combination effects are directly examined using frame models. Based on the peak normal stresses in columns under various loading conditions, combination factors for low-, middle- and high-rise buildings are proposed. Lastly, effects of wind direction on wind load combinations are discussed.