A stochastic model for examining along-wind loading uncertainty and intervention costs due to wind-induced damage on tall buildings

摘要

This study describes some recent results of a numerical study on the wind-induced response of a tall building, contaminated by along-wind loading uncertainty. The study also proposes the use of "intervention costs" in the form of a dimensionless random variable, which nonlinearly depends on the dynamic response of the structure, for the examination of the structural performance during high-wind events. The CAARC building is employed as the benchmark structure. Three nonlinear reduced-order models are used to describe the dynamic response. In these models various hypotheses are introduced to systematically and efficiently simulate both loading uncertainty and cost variability. The generalized models are formulated in terms of stochastic differential equations and are approximately solved by equivalent stochastic linearization. In the case of loading uncertainty analysis, the joint probability density function of the roof-top lateral dynamic displacements in the two primary bending planes of the building is determined as a function of the mean wind speed and the standard deviation of a parametric error term. Dependence of the cross-correlation among the two response components on the input standard deviation of the parametric error term is observed. In the case of the intervention cost analysis, it is noted that the main contributing factor to the distribution of the intervention cost random variable is the mean wind speed. The combination of wind loading uncertainty and projected intervention costs on the dynamic response of the structure is the first step towards the implementation of alternative but rational analysis methods for performance-based wind engineering, applied to tall buildings.