Identification of stick-slip friction in single-degree of freedom system using the random decrement technique

Karsten Krautwald Vesterholm, Tobias Friis, Rune Brincker, Anders Brandt

Research output: Contribution to conferencePaperResearchpeer-review

Abstract

The identification of modal parameters of structures in operational conditions is termed Operational Modal Analysis (OMA). Stick-slip friction is common in many structures, for example offshore oil and gas platforms. The present OMA techniques are based on the assumption of linearity, and when stick-slip friction is present in a system, it is no longer linear. This study investigates how Random Decrement (RD), which is a technique used in OMA, can be used to identify stick-slip friction in a single degree of freedom system. The RD technique can be applied in a set of triggering levels in the same response signal, to calculate RD signatures, each representing the system vibrating at different amplitudes. From RD signatures, the modal parameters can be estimated using time-domain parameter estimation methods. From the changes in modal parameters, associated with the respective amplitude level in the response signal, the nonlinearity is characterized. Two RD triggering conditions are investigated to examine the applicability in identifying the stick-slip nonlinearity. A numerical study is compared with an experimental study of a single degree of freedom system with stick-slip friction.
Original languageEnglish
Publication date2019
Publication statusPublished - 2019
Event9th International Conference on Structural Health Monitoring of Intelligent Infrastructure - St. Louis, United States
Duration: 4 Aug 20197 Aug 2019
Conference number: 9

Conference

Conference9th International Conference on Structural Health Monitoring of Intelligent Infrastructure
Number9
CountryUnited States
CitySt. Louis
Period04/08/201907/08/2019

Cite this

Krautwald Vesterholm, K., Friis, T., Brincker, R., & Brandt, A. (2019). Identification of stick-slip friction in single-degree of freedom system using the random decrement technique. Paper presented at 9th International Conference on Structural Health Monitoring of Intelligent Infrastructure, St. Louis, United States.