Development of wind load evaluation methods considering possible extreme wind pressure distributions applicable to performance based design

测量了不同高宽比和边长比下作用于低层和高层建筑模型表面的脉动风压。计算了最大准静态风荷载效应，如剪力、弯矩和框架应力。基于足够数量的样本，详细分析了引起最大载荷效应的瞬时压力分布。得到的各种风荷载作用下可能的风压分布与基于平均压力分布的准定常风压分布有很大的不同。将Kasperski的荷载-响应相关(LRC)公式应用于框架的内力，并将结果与可能的风压分布进行了比较。然后，对LRC公式的适用范围进行了检验，并研究了风力分量的关联性和相平面轨迹。结果表明，风力分量绝对值的互相关比一般的互相关更适合于风荷载组合的检验。然后，分析了各风荷载分量对柱构件最大正应力的贡献。人们清楚地认识到，如果在计算时仅考虑顺风向荷载分量，则最大法向应力被大大低估。此外，对高层建筑框架模型在极高风速下的非弹性响应进行了分析，明确了高层建筑极限状态附近的建筑行为。在对风荷载和建筑行为进行综合研究的基础上，提出了考虑可能的极限风压分布的风荷载评估方法，用于基于性能的设计。

Fluctuating wind pressures acting on the surfaces of low-rise and high-rise building models with various aspect ratios and side ratios were measured. Maximum quasi-static wind load effects were calculated, such as shear forces, bending moments and frame stresses. The instantaneous pressure distributions causing the maximum load effects were examined in detail based on a sufficient number of samples. The obtained possible wind pressure distributions for various wind load effects were quite different from the quasi-steady wind load distributions based on mean pressure distributions. The load-response correlation (LRC) formula by Kasperski was applied to the internal forces of the frames, and the results were compared with possible wind pressure distributions. Then, the scope of LRC formula was examined.The correlations and phase plane trajectories of wind force components were also investigated. The results suggest that the cross-correlation of the absolute values of wind force components was more appropriate for examining the wind load combinations than ordinary cross-correlations. Then, the contribution of each wind load component to the maximum normal stresses in column members was examined. It was clearly recognized that the maximum normal stress was significantly underestimated if only the along-wind load component was taken into account for calculation. This strongly suggests the importance of considering the combinations of along-wind, across-wind and torsional wind load components even for low-rise or middle-rise buildings.Additionally, non-elastic responses of frame models of high-rise buildings were analyzed for extremely high wind speeds, and the building behaviors around the ultimate states were clarified.Based on these comprehensive studies of wind loads and building behaviors, wind load evaluation methods wee developed that consider possible extreme wind pressure distributions applicable to performance based design.