Abstract
In view of the fact that the lower-order structural modes can be obtained easily in practice and the structural parameters before damage are unknown, the generalized uniform load surface curvature method based on least squares polynomial fitting is proposed to detect structural damage. First of all, the modal flexibility curvature method and the uniform load surface curvature method derived from the modal flexibility curvature are analyzed theoretically, and then, combining with the concept of generalized modal flexibility matrix, the generalized uniform load surface curvature method is obtained, and the generalized uniform load surface curvature method based on least squares polynomial fitting is put forward finally. Second, taking the numerical simulation of a T-beam fixedly supported at both ends as an example, the damage identification effect of the four methods mentioned above is calculated and compared. The results show that the generalized uniform load surface curvature method based on least squares polynomial fitting needs only lower-order modal parameters after the structural damage, can well identify not only the damage location but also the damage degree of the single damage or the multiple damage, and presents small truncation errors. Compared to the other three methods, it has certain advantages. Finally, the damage of a T-shaped simply supported beam is identified by using the proposed method, which verifies the effectiveness of the method, and hence, this method has important practical application value.
Highlights
As the key link of structural health monitoring, structural damage identification has gradually become a hot research topic
The results show that the generalized uniform load surface curvature method based on least squares polynomial fitting needs only lower-order modal parameters after the structural damage, can well identify the damage location and the damage degree of the single damage or the multiple damage, and presents small truncation errors
The results show that the four indices can identify single damage and identify multiple damage under the case of obtaining the lower-order modal parameters; the recognition effect of uniform load surface curvature (ULSC) is better than that of modal flexibility curvature (MFC), General Uniform Load Surface Curvature (GULSC) has smaller truncation error than ULSC, and only LGC does not need the information before structural damage
Summary
As the key link of structural health monitoring, structural damage identification has gradually become a hot research topic. The above-mentioned research methods can identify the damage and give the damage location and degree These methods generally require the information before and after structural damage, and some of them acquire the structural high-order modes, so their practical application and promotion have certain difficulty. Combined with the above analysis, the authors propose a damage identification index that is the generalized uniform load surface curvature (ULSC) based on the least squares fitting polynomial, which can obtain a good damage detection effect only by the lowerorder modal parameters after structural damage. The results show that the four indices can identify single damage and identify multiple damage under the case of obtaining the lower-order modal parameters; the recognition effect of ULSC is better than that of MFC, GULSC has smaller truncation error than ULSC, and only LGC does not need the information before structural damage. LGC has better advantages and practical application value over the other three methods
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
