Title Wind Loading Combination considering Response Correlations between Acrosswind and Torsional Directions
Authors Kim, Wonsul ; Kim, Yong Chul
DOI http://dx.doi.org/10.5659/JAIK_SC.2015.31.4.55
Page pp.55-62
ISSN 1226-9107
Keywords Wind load combination ; Power spectrum density ; Root coherence ; Response correlation coefficient ; Time history analysis ; Spectral modal analysis ; (Super-)Tall building ; Wind tunnel test
Abstract The wind tunnel test was conducted to investigate characteristics of fluctuating wind forces acting on tall buildings for various side ratios (D/B=1.0, 1.1, 1.2, 1.3, 2.0 and 3.0) and different terrain roughnesses. Further, the wind load combination was examined by the correlation of the displacement response between acrosswind and torsional directions through Spectral Modal Analysis Method and Time History Analysis Method. As a result, there was no significant effect of the changing of terrain roughnesses on fluctuating moment coefficients for acrosswind and torsional directions, but they were varied with the changing of wind directions. Acrosswind overturning moment coefficients were highly correlated with the torsional moment coefficient with the increase in wind directions. The response and correlation obtained by Time History Analysis were good agreement with those of Spectral Modal Analysis. Also, the response correlation between acrosswind and torsional directions was highly affected by natural frequency ratios. Hence, the wind load combination for acrosswind and torsional directions shall be considered that when the natural frequencies between acrosswind and torsional directions are close to each other.