大型桥梁结构模型修正的RBF响应面与子结构方法

针对大型复杂桥梁结构模型修正中面临的问题，本项目将通过理论方法分析、试验研究和工程应用，进行深入、系统和模型与原型验证研究。首先，分析桥梁结构模型修正中参数和特征信息的选取及其对模型修正的影响和规律，以便合理选取待修正参数和充分利用有限的实测信息；其次，研究基于径向基函数(RBF)响应面方法并应用于桥梁结构模型修正，该方法把优化过程中反复迭代计算的工作由有限元模型转移至具有明确数学表达式的响应面模型，计算效率大幅提高，结合桥梁健康监测系统，可实现大型复杂桥梁的快速、高效和实时地模型修正；第三，针对斜拉桥提出一种子结构方法，该方法通过斜拉桥自身的力学特性划分子结构，无须对结构进行截断或施加外部约束，即确保结构的完整性，又大为简化计算过程，具有较强的工程实用性；最后，通过几类不同复杂层次的实验室桥梁Benchmark模型对研究的问题进行试验研究，并通过实际桥梁实现研究成果的原型验证与工程应用。

Focus on the problems in the model updating of large-scale bridges, this project does intensive, systematic, laboratorial models and engineering structures validating research through theory and method analysis, experimental studies and engineering applications. First, the selection of updating parameters and characteristic information, as well as their disciplines and influences to model updating are analyzed in order to select reasonable updating parameters and effectively utilize the limited testing information. Second, the response surface method based on radial basis functions (RBFs) is investigated and applied on the model updating of bridge structures. In the optimization process, this method transforms the iterative calculation by the finite element model to that by the response surface with explicit mathematical expressions, which considerably improves the computational efficiency. Combined with the bridge health monitoring system, it can achieve the fast, efficient and real-time model updating of large-scale and complex bridges. Third, a substructure mthod is proposed for cable-stayed bridges. The substructures are divided according to the mechanical characteristics of the structure without cut-offs or external constraints, thus keeps the structural integrity, greatly simplifies the calculation process and has strong engineering applicability. Finally, all the research contents of this project are carried out the experiments study on several laboratorial bridge benchmark models with different levels of complexity, and engineering applications are realized by real bridge structures.