大跨悬索桥面向结构健康监测的基准有限元模型

为描述大跨桥梁服役前完好状态时的结构性能,建立了润扬悬索桥面向结构健康监测的基准有限元模型。首先,探讨面向健康监测需求、建立适度精细基准模型的目标,提出了采用正交异性壳单元等效钢箱梁的建模策略。然后,就钢箱梁的简化模拟、桥塔的动力模型修正、成桥状态初始构形及内力的确定、主梁边界条件的确定和钢箱梁局部应力分析等关键技术问题进行了详细的研究。最后,对所建立的基准有限元模型采用润扬悬索桥成桥试验的实测结果进行了验证。结果表明,该基准模型能从整体结构尺度与局部构件尺度两个方面准确地模拟结构的实际性能,从而为润扬悬索桥的损伤识别与状态评估提供了可靠的结构描述与分析依据。

Structural-health-monitoring-oriented Baseline Finite Element Model of a Long-span Suspension Bridge

A structural-health-monitoring-oriented baseline finite element(FE) model of the Runyang Suspension Bridge is presented for the purpose of representing actual behaviours of complete bridge.The target of structural-health-monitoring-oriented moderate precise FE model was discussed firstly,and the modeling methodology of steel-box-girder using orthotropic shell element is proposed.Then,some important issues in the modeling process,such as the simplified modeling of steel-box-girder,the model updating of bridge tower,the initial equilibrium configuration of complete bridge,the boundary conditions of bridge deck,and the analysis of stress distribution in steel-box-girder,are studied in detail.Finally,the model validation using field-test results is conducted.Comparison shows that the proposed baseline model can be used as a reliable representation and analysis model for the damage diagnosis and condition assessment in structural health monitoring for the Runyang Suspension Bridge.