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。
The concrete dam′s vibration information during operation is hard to be measured accurately.Based on the transmissibility function theory,we applied vibration excitation to the concrete dam,and established the transmissibility function with the dynamic response information.In addition,since the information characteristics and the correlation of the variables can be represented by the information entropy and mutual information,we therefore proposed a new index to identify and locate structural damages.This method extracts damage characteristics directly from response information without obtaining the external vibration excitation information.The simulation and experimental results of the concrete gravity dam showed that when the damage degree was greater than 3%,the index could well realize damage identification and location,and it was suitable for both single damage and multiple damages.With reasonable arrangement of the measuring points according to the structural characteristics,the index can realize local damage identification,and has great practical application value in the damage detection of the concrete dam.
出处
《南水北调与水利科技》
CSCD
北大核心
2017年第5期141-145,155,共6页
South-to-North Water Transfers and Water Science & Technology
基金
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)~~
关键词
混凝土坝
动力响应
损伤识别
传递率函数
信息熵
concrete dam
dynamic response
damage identification
transmissibility function
information entropy
