Operational modal analysis based prediction of actual stress in an offshore structural model. (2017)

• Record Type: Journal Article
• Authors: Tarpø, Marius; Nabuco, Bruna; Skafte, Anders; Kristoffersen, Julie; Vestermark, Jonas; Amador, Sandro; Brincker, Rune
• Is Part Of: Procedia engineering. Volume 199(2017)
• Page Start: 2262
• Page End: 2267
• Publication Date: 2017
• Subjects: Operational Modal Analysis -- Modal Based Fatigue Estimation -- Modal Expansion -- Monitoring; Engineering -- Congresses; Engineering -- Periodicals; Engineering; Conference proceedings; Periodicals; 620.005
• DOI: 10.1016/j.proeng.2017.09.234
• Languages: English
• ISSNs: 1877-7058

Abstract

Abstract: In this paper the accuracy of predicting stresses directly from the operational responses is investigated. The basic approach to the stress prediction is to perform an operational modal analysis (OMA) and then applying a modal filtering to the operating response, so that the modal coordinates of all significant modes are known. Next, the experimental mode shapes are expanded using a finite element (FE) model together with the local correspondence principle to estimate the displacements in all degrees of freedom of the FE model, and strain is predicted using the strain mode shapes. The accuracy of the approach is assessed by comparing the predicted and measured strains.