Evaluation of Mean Recurrence Intervals of Wind Effects for Tall Building Design

摘要

Mean recurrence intervals (MRIs) of wind effects for the strength design (SD) of flexible buildings by the wind-tunnel method are based on estimates of total uncertainties that do not account for uncertainties in the dynamic parameters. This paper presents a procedure for assessing this practice. The procedure accounts for the probability distributions of total uncertainties in basic wind effects corresponding to MRIs of 50 or 100 years. The total uncertainties are estimated for two cases. For Case 1, only uncertainties in the wind loading are taken into account. For Case 2, uncertainties in both the wind loading and the dynamic parameters are considered. Cumulative distribution functions (CDFs) of the total uncertainties in the basic wind effects are determined by Monte Carlo simulation. To assure risk consistency, the MRIs of wind effects considered for SD correspond in both cases to the same upper confidence bound of the basic wind effects. For a 305-m-tall symmetrical steel building, the requisite MRIs are larger for Case 2 than for Case 1 by at most 80%. These increases corresponded to wind effects considered for SD larger for Case 2 than for Case 1 by at most 6%.