Nonlinear system identification of strongly nonlinear beats in the dynamics of a beam with a local stiffness nonlinearity

M. Kurt, Alexander F Vakakis, D. M. McFarland, L. A. Bergman, M. Eriten

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

In this paper,we consider a linear cantilever beam attached to ground through a strongly nonlinear stiffness at its free boundary.We consider the uniform, homogeneous cantilever beam which is made of steel with density 7850 kg/m3 andYoung's modulus, E, 200 GPa, as shown in Fig. 1, with dimensions L × h × t =1.311 × 0.0446 × 0.008 m. The system includes a nonlinear spring (cubic) attached at its tip, which provides a nonlinear restoring force to the system. An impact force is applied at 0.4m with amplitude of 10 kN, approximately. Since the nonlinear stiffness has no linear component, it is essentially nonlinear and non-linearizable. We show that the strong nonlinearity mostly affects the lower-frequency bending modes and causes strongly nonlinear beating phenomena. We develop nonlinear system identification method, which is capable of identifying this type of strongly nonlinear modal interactions. It is based on an adaptive step-by-step application of Empirical Mode Decomposition (EMD) approach to the measured time series, which makes it valid for multi-frequency beating signals.

Original languageEnglish (US)
Title of host publicationSafety, Reliability, Risk and Life-Cycle Performance of Structures and Infrastructures - Proceedings of the 11th International Conference on Structural Safety and Reliability, ICOSSAR 2013
Pages1945-1947
Number of pages3
StatePublished - 2013
Event11th International Conference on Structural Safety and Reliability, ICOSSAR 2013 - New York, NY, United States
Duration: Jun 16 2013Jun 20 2013

Other

Other11th International Conference on Structural Safety and Reliability, ICOSSAR 2013
CountryUnited States
CityNew York, NY
Period6/16/136/20/13

    Fingerprint

ASJC Scopus subject areas

  • Civil and Structural Engineering
  • Safety, Risk, Reliability and Quality

Cite this

Kurt, M., Vakakis, A. F., McFarland, D. M., Bergman, L. A., & Eriten, M. (2013). Nonlinear system identification of strongly nonlinear beats in the dynamics of a beam with a local stiffness nonlinearity. In Safety, Reliability, Risk and Life-Cycle Performance of Structures and Infrastructures - Proceedings of the 11th International Conference on Structural Safety and Reliability, ICOSSAR 2013 (pp. 1945-1947)