基于谐波合成法的风荷载数值模拟分析  

Numerical Simulation Analysis of Wind Load based on Harmonic Synthesis Method

作　　者：唐言志 李乃旺 TANG Yan-zhi;LI Nai-wang(Henan Transport Investment Group Co.Ltd.,Zhengzhou 450000,China;CHELBI Engineering Consultants Inc.,Beijing 100029,China)

机构地区：[1]河南交通投资集团有限公司,郑州市450000 [2]华杰工程咨询有限公司,北京市100029

出　　处：《公路》2022年第10期179-185,共7页Highway

摘　　要：为获得某大跨度公铁两用斜拉桥的静动风荷载,对主塔和主梁的风场进行数值模拟。针对该桥的结构特点,将全桥三维脉动风速场简化为多个线状的一维脉动风场。以规范推荐值为输入参数,采用谐波合成法模拟出脉动风速时程序列,并检验了样本风速谱和相关函数。基于模拟点的平均风和脉动风速计算分析了主塔、主梁的静风荷载和抖振力。结果表明,不同模拟点脉动风速谱、相关函数与目标值整体吻合良好,验证了模拟办法的有效性;脉动风作用下,主跨跨中风阻力幅值在-557~731 kN范围波动,风升力幅值在-326~326 kN范围波动,风力矩幅值在-686~852 kN·m范围波动,风阻力波动幅值明显大于风升力波动幅值。模拟得出的全桥风速和风荷载时程序列,可为后续求解桥梁风振响应奠定基础。In order to obtain the static and dynamic wind load of a long-span highway railway cable-stayed bridge,the wind field of the main tower and main beam is numerically simulated.According to the structural characteristics of the bridge,in this paper the 3 D turbulence wind field is simplified into multiple 1 D turbulence wind filed.Taking the recommended value as the input parameter,the time series of fluctuating wind speed is simulated by means of harmonic synthesis method,and the sample wind speed spectrum and correlation function are tested.Based on the average wind and fluctuating wind speed at discrete points,the static wind load and buffeting force of the main tower and main beam are calculated and analyzed.The results show that the fluctuating wind speed spectrum and correlation function at different simulation points are in good agreement with the target value,which verifies the effectiveness of the simulation method.Under the fluctuating wind,the amplitude of wind resistance is in the range of-557~731kN of the main span fluctuates,the amplitude of wind lift fluctuates is in the range of-326~326kN,The amplitude of torsional moment fluctuates is in the range of-686~852kN·m,indicating that the fluctuation amplitude of wind resistance is significantly greater than that of wind lift.The simulated wind speed and wind load time series of the whole bridge can lay the foundation for the subsequent solution of the bridge’s wind vibration response.

关 键 词：公铁两用斜拉桥 谐波合成法 脉动风速 风荷载 数值模拟 

分 类 号：U441.2[建筑科学—桥梁与隧道工程]