基于冲击振动与长标距应变传感的桥梁测试方法及其理论创新

How to guarantee the safety and to minimize the maintenance cost of numerous bridges in national highway networks is a challenging problem. An impact testing method of the bridge using long-gauge strain sensing technology is proposed and its theory development for structural identification will be investigated. It has the merits of identifying deep-level structural parameters by measuring not only structural responses but also impacting forces. The long-gauge strain measurements have also the feature of revealing both local and global characteristics of the structure. Based on those merits, the theory of identify deep-level structural parameters and evaluate structural safety including its long-term performance will be developed. The novelty of the proposed method is that it not only outputs basic structural parameters such as frequency and mode shapes, but also identifies deep-level parameters including structural strain flexibility and displacement flexibility, thus it is much more reliable for effective structural performance evaluation. Especially, the developed long-term performance stochastic evaluation theory outputs statistical information of the identified parameters, thus it provided necessary data for probability-based structural risk analysis. In brief, the proposed method is potential to be widely applied in engineering practices.

如何保障国家公路网上为数众多桥梁的结构安全并实现经济有效的全寿命周期维护是我国基础设施管理中迫切需要解决的关键科学问题。本项目提出一种基于冲击振动与长标距应变传感的桥梁测试方法并开发其理论基础。其冲击力可测的特点为识别结构更完备信息奠定了理论基础，另一方面，其采用的长标距应变具有同时反映结构宏微观特征的独特优势。基于上述特点，本项目拟进行针对所提议测试方法的结构深层次参数识别的理论创新，并进一步开发基于定期测试的结构长期性能随机评估理论。它的创新之处在于能够识别位移柔度和应变柔度等结构深层次信息，从而有望突破传统方法识别结果过于简单难以实现结构有效评价的瓶颈。特别的是，它能够输出一定历史时期内结构性能劣化的统计特征，从而为后续的以概率为基础的结构风险分析奠定基础。总的来说，所提议测试方法具有明确的工程意义同时又建立在深厚的理论基础之上，从而有望进行切实可靠的桥梁诊断并在工程应用中推广。

如何保障国家公路网上为数众多桥梁的结构安全并实现经济有效的全寿命周期维护是我国基础设施管理中迫切需要解决的关键科学问题。本项目提出了一种基于冲击振动与长标距应变传感的桥梁测试方法并开发其理论基础。其冲击力可测的特点为识别结构更完备信息奠定了理论基础，另一方面，其采用的长标距应变具有同时反映结构宏微观特征的独特优势。基于上述特点，本项目已经进行针对所提议测试方法的结构深层次参数识别的理论创新，并进一步开发出了基于定期测试的结构长期性能随机评估理论。它的创新之处在于能够识别位移柔度和应变柔度等结构深层次信息，从而有望突破传统方法识别结果过于简单难以实现结构有效评价的瓶颈。特别的是，它能够输出一定历史时期内结构性能劣化的统计特征，从而为后续的以概率为基础的结构风险分析奠定基础。本项目所提相关方法已经在扬州北澄子河大桥等多座桥梁当中进行试验应用。