基于较完善的斜拉索有限元模型,分析讨论了斜拉索张力、抗拉刚度、抗弯刚度以及线密度等不同设计参数对长索和短索计算频率的相对灵敏度,确定了最敏感设计参数。在此基础上,根据优化理论,对洞庭湖大桥拉索进行基于最敏感设计参数的动力模型修正,修正后的模型的动力特性更加趋近于实测值。修正后的斜拉索有限元模型可以作为拉索张力评估的基准。
Based on a more perfect finite element model of stay cable, the relative sensitivity of calculational frequencies for long stay cable and short stay cable were analyzed respectively, according to the different design variable of cable such as tension force, tensile rigidity, flexural rigidity , density and the most sensitivity design variable was established. On the basis, according to the optimization theory, the dynamic finite element model updating of a stay-cable of Dongting Lake Bridge based on the most sensitive design variable was processed. The final updated FE model was able to produce natural frequencies closer to the test ones. The updated FE model was useful for the reference model to tension force assessment.