基于MF-EI法的水闸底板脱空参数反演  

Inversion of Void Parameters of Sluice Floor Based on MF‑EI Method

作　　者：李火坤[1] 方静 黄伟[1] 万子豪 LI Huokun;FANG Jing;HUANG Wei;WAN Zihao(School of Infrastructure Engineering,Nanchang University Nanchang,330031,China)

机构地区：[1]南昌大学工程建设学院,南昌330031

出　　处：《振动．测试与诊断》2024年第5期936-942,1038,1039,共9页Journal of Vibration,Measurement & Diagnosis

基　　金：国家自然科学基金资助项目(52079061,51909115,51879126);江西省研究生创新专项资金资助项目(YC2021-S052)。

摘　　要：为了更好地解决水工结构以损伤诊断为目标的传感器布置问题,以软基水闸为研究对象、水闸底板脱空为损伤类型,针对传统有效独立法未考虑结构损伤信息的缺陷,将模态柔度作为结构损伤敏感特征量,并引入结构的模态柔度修正有效独立法,提出基于模态柔度-有效独立法(modal flexibility-effective independent method,简称MFEI)的水闸底板脱空参数反演方法。采用模态置信准则、Fisher信息阵、条件数准则和奇异值分解比准则4种评价指标,分别对距离系数-有效独立法(distance coefficient-effective independence method,简称DC-EI)、有效独立-总位移法(effective independence-total displacement method,简称EI-TD)和MF-EI法进行评价,并将3种方法得到的布置方案应用到不同工况下软基水闸底板脱空动力学反演中,对比分析3种方法各工况脱空参数的反演结果。结果表明:MF-EI法测得的模态矩阵具有更好的正交性、可观测性和模态扩阶性,同时保留了对软基水闸底板脱空敏感的损伤信息,3种工况下的脱空参数反演识别精度分别提高至97.5%,96.1%和75.9%,是一种较为有效的水闸底板脱空参数反演方法。In order to solve the problem of sensor placement in hydraulic structures aiming at damage diagnosis,soft foundation sluice is taken as the research object,and the floor void of sluice on soft foundation is the damage type.Aiming at the defect that the traditional effective independent method does not consider the structural damage information,the modal flexibility is regarded as the structural damage-sensitive feature quantity,and the effective independent method of the modal flexibility correction of the structure is introduced.An inversion method of sluice floor voiding parameters based on the modal flexibility-effective independent method(MFEI)is proposed.Modal confidence criterion,Fisher information matrix,condition number criterion and singular value decomposition ratio criterion are used to evaluate three methods:distance coefficient-effective indepen‑dence method (DC-EI), effective independence-total displacement method (EI-TD) and MF-EI method. Thelayout schemes of the three methods are applied to the dynamic inversion of the floor void of sluice on soft foundationunder different working conditions, and the inversion results of the void parameters of each method arecompared and analyzed. The result shows that the modal flexibility-effective independence method makes orthogonality,observability and modal expansion of the measured modal matrix better, while retaining the dam ‑age information sensitive to the vacancy of the soft foundation sluice floor. The accuracy of inversion and identificationof the void parameters of the situation have been improved to 97.5%, 96.1%, and 75.9%, respectively.It is a more effective inversion method for sluice floor voiding parameters.

关 键 词：软基水闸 底板脱空 传感器优化布置 模态柔度-有效独立法 反演 

分 类 号：O329[理学—一般力学与力学基础] TV31[理学—力学]