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提出了长跨桥的结构动力响应和局部破坏的多级数值分析方法。首次研究了长跨桥有限元模型的多级数值分析的策略。基于设计图纸拓展了Tsing Ma桥的多级数值模型以及对此模型的策略。提出了动力响应和局部破坏的多级数值分析过程,连接焊缝处的局部退化过程能够解释破坏的主要作用和对结构响应的非线性影响。基于ABAQUS软件和改进程序,通过便于大型土木建筑应用的用户界面,实现了多等级计算。在将该方法应用于Tsing Ma桥之前,计算程序的精度通过两个典型实例进行验证。基于安装在Tsing Ma桥上的结构健康监测系统所获得的在线监测数据,在正常荷载下,采用拓展模型和计算程序对Tsing Ma桥的整体动力响应和桥的纵向桁架中两个典型焊接细部的局部损伤累积进行了数值分析。累积损伤的最大值出现在上部焊缝的脚部和/或斜杆与节点板相交的下弦杆处。全连接计算所得的疲劳寿命小于非全连接时的疲劳寿命,这说明在用多级数值计算方法分析结构损伤时应该考虑损伤与结构响应间明显的交互作用。
The multi-level numerical analysis method of structural dynamic response and local failure of long-span bridges is proposed. For the first time, the multi-level numerical analysis of long-span bridge finite element model is studied. Based on the design drawings, Tsing Ma Bridge’s multi-level numerical model and its strategy are extended. A multi-level numerical analysis of dynamic response and local failure is proposed. The local degenerate process at the weld joint can explain the main role of failure and the nonlinear effect on the structural response. Based on ABAQUS software and improved procedures, multi-level calculations are achieved through a user interface that facilitates large-scale civil engineering applications. Before applying this method to Tsing Ma Bridge, the accuracy of the calculation program was verified by two typical examples. Based on the on-line monitoring data obtained from the structural health monitoring system installed on the Tsing Ma Bridge, the overall dynamic response of the Tsing Ma Bridge and the two typical welded details of the longitudinal truss of the bridge under normal load are analyzed using an extended model and a calculation program Local damage accumulation was numerically analyzed. The maximum cumulative damage occurs at the foot of the upper weld and / or at the lower chord where the diagonal bar intersects the gusset plate. The fatigue life of the full connection calculation is less than the fatigue life of the non-full connection, which shows that the obvious interaction between the damage and the structural response should be considered in the analysis of structural damage using multi-level numerical methods.