斜拉桥顺桥向水平振动频率的实用估算方法

Practical Method for Estimating Horizontal Vibrational Frequency of Cable-stayed Bridge

研究斜拉桥成桥自振频率,采用双质点法建立顺桥向水平振动分析模型,推导出纵飘计算公式,并将公式进行简化,得到实用估算公式。采用Midas Civil软件用有限元法分别对齐河黄河大桥等建立三维有限元模型,根据成桥阶段模态测试结果,对比分析有限元分析、双质点法、双质点模型估算公式和现场模态测试结果,表明了有限元法能够精确模拟桥梁实际受力状态,而双质点法和估算公式为斜拉桥在方案设计阶段抗震抗风性能的快速判断提供参考。

The natural vibration frequency of cable-stayed bridge is studied.The horizontal vibrational analysis model is established by using the double-particle method to deduce the calculation formula of longitudinal drift.The formula is simplified to obtain the practical estimation formula.The three-dimensional finite element models of Qihe Yellow River Bridge and etc.are established by the finite element method of Midas Civil software.Based on the modal test results of the finished bridge stage,the test results of finite element analysis,double-particle method,double-particle model estimating formula and field modal test are compared and analyzed.The results show that the finite element method can accurately simulate the actual stress state of the bridge,and the double-particle method and the estimation formula can provide the reference for the quick judge of anti-seismic and anti-wind performances of cable-stayed bridge in the scheme design stage.