含偏心高层建筑风致弯扭耦合振动研究

Wind induced bending-torsional coupled vibration of a high-rise building with bi-asymmetric cross-section

针对偏心高层建筑风致弯扭振动问题,采用Euler-Bernoulli梁模型,选择建筑截面刚度中心为参考坐标原点,坐标x轴平行于风向角,按照双向弯扭耦合振动理论,求取振型和自振频率;然后以随机振动理论为基础,发展了连续梁模型的三维风振理论,给出了风致弯扭耦合振动时顶层角点加速度响应表达式。针对具体算例,结合实际风洞试验拟合数据,运用该方法进行计算,并与原文献计算结果比较,分析了误差来源;并研究了刚度中心、质心偏离对建筑自振频率、顶层角点加速度响应的影响。

With wind-induced bending-torsional coupled vibration of a high-rise building with bi-asymmetric cross sections was studied.The high-rise building was modeled as an Euler-Bernoulli beam.The origin of the reference point of each cross section was chosen to coincide with the stiffness center of the cross section and X axis was parallel to wind directions.Natural frequencies and modal shapes of the bending-torsional coupled vibration were calculated firstly.Then,a method for wind-induced 3D bending-torsional coupled vibration of the beam model was developed base on stochastic vibration theory,and the expressions for the top rise corner acceleration response were presented.An illustrative example was given and the results were compared with those of other related references.The effect of position of stiffness center and mass center on natural frequencies and acceleration responses was discussed.