斜拉桥结构模型修正的子结构方法

A substructure method for structural model updating of long-span cable-stayed bridges

针对大跨斜拉桥结构提出了一种子结构模型修正方法。根据斜拉桥结构体系特征,从空间上划分几个比较独立的子结构。对包括所有子结构特征信息和待修正参数的整体结构,进行特征信息对参数的灵敏度分析,验证各子结构之间的相对独立性,并确定子结构模型修正的顺序。基于各子结构的特征信息建立目标函数,采用遗传优化算法,依次对各子结构进行模型修正。以某大跨斜拉桥试验室物理模型为研究对象,对该方法进行了数值仿真和试验验证。基于仿真数据的子结构模型修正精准度高,基于实测数据的修正结果能得到与实际情况相符的合理解释。因此,该斜拉桥模型修正的子结构方法切实有效,且易于工程应用。

A substructure method of model updating was proposed for cable-stayed bridges.Several substructures were divided according to structural system properties of cable-stayed bridges.Then,the sensitivity analyses of structural response characteristics with respect to the updating design parameters of cable-stayed bridges were performed to check the independency and resonableness of the substructures,and to determine the model updating sequence of the substructures. An objective function was constructed by using the residuals between tested and analytical data of each substructure,and the genetic algorithm was implemented to optimize model updating of each substructure.Numerical study and experimental verification of the proposed substructure model updating approach were performed based on a scaled physical model of a long-span cable-stayed bridge.The results indicated that the model updating based on the simulated data has a higher precision,and the model updating based on experimental data can get reasonable explains being consistent with the actual situation,so this substructure method works well and can be easily implemented in practice.