变截面刚度与质量分布高层结构风振动力反应分析计算

Evaluation of wind induced dynamic response for high rise buildings with uneven rigidity and mass distribution

采用Rayleigh-Ritz能量法确定非均匀质量与截面刚度悬臂杆的第一阶自振频率与振型,并根据Daven-port脉动风速谱得出了顺风向脉动风压谱密度函数,得出了类似的高层与高耸结构顺风向风振动力反应的计算方法.计算结果表明,变截面刚度与质量分布的高层结构或高耸结构在顺风向脉动风压作用下,结构的风振反应以共振响应为主,背景响应只占次要的部分;计算风振系数或进行结构振动控制设计时,应该考虑质量分布函数与截面刚度分布函数变化的影响.

A method for evaluating wind induced dynamic response along the wind direction for high rise buildings or tall and slender buildings with uneven distribution mass and rigidity was presented.It started from the determination of natural frequencies and vibration modes with Rayleigh-Ritz method.The Davenport fluctuating velocity spectrum density function was adopted to generate the wind load function in the frequency domain.Evaluation work was performed for a practical building.The results show that the resonant response take the significant part of the total dynamic response and the non-resonant response could be neglected.The uneven distribution for mass and rigidity should be taken into account in computing and designing.