基于动力参数的RC梁结构损伤识别方法研究  

Research on damage identification method of RC beam structure based on dynamic parameters

作　　者：胡健 沈磊[1] 鲍华[1] 任宇 黄晨 Hu Jian;Shen Lei;Bao Hua;Ren Yu;Huang Chen(China Railway Siyuan Survey and Design Group Co.Ltd,Wuhan 430063,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]中铁第四勘察设计院集团有限公司,湖北武汉430063 [2]西南交通大学土木工程学院,四川成都610031

出　　处：《建筑科学》2023年第7期82-89,共8页Building Science

基　　金：国家重点研发计划(2016YFC0802205);铁四院科研课题(2018K139)。

摘　　要：现有RC梁结构动力损伤识别方法存在对局部损伤不敏感、各阶模态振型不能完整反映结构损伤信息等问题,且未考虑不同阶振型对结构损伤识别敏感度的影响。本文提出了一种基于动力参数的RC梁结构损伤识别方法。首先,根据振动力学理论,推导RC梁的模态振型曲率与结构刚度的计算公式,结合振型曲率,建立基于动力参数的损伤识别方法。然后,通过有限元软件ABAQUS构建钢筋混凝土简支梁模型,利用有限元单元刚度下降模拟梁结构损伤,并结合各阶振型曲率对方法进行修正。最后,开展了1根未损伤梁和5根预损伤梁的预损伤RC梁动力试验,对损伤识别方法进行了验证。研究结果表明:振型差曲率能够反映结构的损伤状态,基于敏感度修正后的损伤指标的识别效果更好,能更好地对结构的损伤状态进行判断。损伤指标值在损伤位置处产生峰值,且其值与损伤程度呈正相关。该损伤识别方法不仅能够准确地识别损伤出现的位置,而且能够得到与实际相符的损伤程度识别结果。The existing methods of dynamic damage identification of RC beam structure have some problems,such as not sensitive to local damage,and the failure of all modes to reflect the damage information of structure,and the influence of different modes on the sensitivity of structural damage identification is not considered.This paper presents a method of damage identification of RC beam structure based on dynamic parameters.Firstly,according to the theory of vibration mechanics,the formula of modal mode curvature and structural stiffness of RC beam is derived.Combined with the mode curvature,a damage identification method based on dynamic parameters is established.Then,the model of reinforced concrete simply supported beam is constructed by ABAQUS,and the damage of beam structure is simulated by the finite element stiffness drop,and the method is modified by combining the curvature of different modes.Finally,the dynamic test of one undamaged beam and five pre damaged RC beams is carried out,and the damage identification method is verified.The results show that the mode difference curvature can reflect the damage state of the structure,and the damage index modified by sensitivity is better to identify and judge the damage state of the structure.The damage index value has a peak value at the damage location,and its value is positively correlated with the damage degree.The damage identification method can not only accurately identify the location of damage,but also can get the damage degree recognition results which are consistent with the actual situation.

关 键 词：RC梁结构 损伤识别 动力参数 有限元分析 动力试验 

分 类 号：TU375.1[建筑科学—结构工程]