基于模态应变能和Bayes理论的梁结构损伤识别  

Damage identification of beam structures based on modal strain energy and Bayesian data fusion theory

作　　者：卫军[1] 杜永潇 吴志强[1] 黄敦文 刘康 WEI Jun;DU Yongxiao;WU Zhiqiang;HUANG Dunwen;LIU Kang(School of Civil Engineering,Central South University,Changsha 410075,China)

机构地区：[1]中南大学土木工程学院

出　　处：《铁道科学与工程学报》2019年第8期2052-2061,共10页Journal of Railway Science and Engineering

基　　金：国家自然科学基金资助项目(51378501,51578547,51778628)

摘　　要：为提高对梁结构损伤识别的准确性,改善单一方法对梁结构损伤识别的灵敏性,在模态应变能变化率指标的基础上,提出一种经Bayes数据融合理论处理的改进损伤识别方法。通过对一预应力混凝土模型梁的有限元分析和试验研究,提取模态参数并处理,比较经Bayes数据融合的损伤识别指标和单元模态应变能变化率指标,验证改进方法的有效性和实用性。研究结果表明:相比于模态应变能法,经Bayes数据融合的损伤识别方法能够更加准确和有效地确定梁结构单处损伤和多处损伤的位置;随着损伤程度的增加,Bayes融合概率变大;Bayes数据融合放大了损伤识别指标在不同程度损伤单元之间、损伤单元和完好单元之间的差别,对损伤更敏感;对于不同程度的损伤,先通过Bayes融合准确定位损伤,再利用对应MSECR值可以有效识别损伤程度。In order to improve the accuracy of damage identification and the sensitivity of single method to damage identification for beam structures,an improved damage identification method using Bayesian data fusion method was adopted on the basis of the modal strain energy change rate index.Based on the finite element analysis and experimental study of a prestressed concrete model beam,the modal parameters were extracted and processed,and the effectiveness and the practicality of the improved method were verified by comparing the damage identification result of Bayes data fusion and the element modal strain change rate index.The results show that compared with the modal strain energy,the Bayes data fusion damage identification method can be more accurate and effective to determine single damage and two damages’ locations for the bridge structures.With the increase of the damage degrees,the Bayes fusion probability becomes larger.Bayes data fusion amplifies the difference between the different degree damage elements,damage element and intact element,and it is more sensitive to damage.For different degrees of damage,the Bayes fusion is used to accurately locate the damage,and then the corresponding MSECR value can be used to effectively identify the degree of damage.

关 键 词：损伤识别 模态应变能 Bayes数据融合理论 梁结构 

分 类 号：TU311[建筑科学—结构工程]