[关键词]
[摘要]
混凝土坝运行过程中受到的振动激励信息一般难以精确获取,基于传递率函数理论,对混凝土坝施加一定的振动激励,通过测得的动力响应信息计算传递率函数,同时利用信息熵及互信息可以表征变量的信息特征及相关性,提出了识别和定位结构损伤的指标。这种方法不需要获得外界的激励信息,直接利用结构的响应信息提取损伤特征。混凝土重力坝的仿真和试验结果表明,在损伤程度高于3%的情况下,施加的振动激励能较好地实现损伤识别和定位,并适用于单一损伤和多损伤;根据结构特性合理优化布置测点可以实现局部损伤识别,对混凝土坝的损伤检测有较好的实际应用价值。
[Key word]
[Abstract]
In the process of operation, the concrete dam’s vibration information is hard to be measured accurately, based on transmissibility function, the vibration excitation was applied to the concrete dam, and transmissibility function is established through the dynamic response information. In addition, the information characteristics and the correlation of the variable can be characterized by the information entropy and mutual information, based on that, a new identification and localization of structural damage index is presented. This method extracts damage character without obtaining the outside vibration excitation information. Concrete gravity dam of the simulation and experimental results show that while the damage degree is greater than 3%, applying the vibration excitation can well realize the damage identification, and it is suitable for single damage and multiple damaged. The local damage can be well identified by reasonable arrangement of the measuring points according to the structural characteristics, and with great practical application value in concrete dam’s damage identification.
[中图分类号]
[基金项目]
国家自然科学基金 (51579085;51279052);江苏省“六大人才高峰”项目(JY-008,JY003);国家自然科学基金重点项目(51139001;41323001);中央高校基本科研业务费项目(2015B20714)