Effect of Partially Correlated Wind Loading on the Response of Two-Way Asymmetric Systems: The Impact of Torsional Sensitivity and Nonlinear Effects

Abstract

Load eccentricities in structural systems are associated with an increase in the torsional response. Typically, these eccentricities are defined based on the distance between the center of mass and the center of stiffness at a predefined story. If the structural system is subjected to dynamic loading, such as wind loading, instantaneous load eccentricities due to the displacement of the center of mass may occur. An evaluation of this nonlinear effect for two-way asymmetric systems under wind loading is presented in this study. To model the structural systems and the instantaneous load eccentricities, coupled nonlinear differential equations are assembled and solved by using the state space model. The structural systems proposed are subjected to time histories of turbulent wind forces, which are simulated based on a newly developed methodology that includes the correlation of wind forces. The impact of the instantaneous load eccentricities and correlation of wind forces and torsional moment on the wind-induced response of the structural systems analyzed is discussed in detail.

Keywords

• wind force correlation
• wind force simulation
• wind-induced torsion
• geometric non-linearity
• second order effect