Coupled Bending and Torsional Vibrations Analysis of Cracked L-shaped Beam

크랙을 가진 L형 단면 보의 횡-비틀림 연성진동 해석

  • 손인수 (동의대학교 기계공학과) ;
  • 김창호 (동의대학교 기계공학과) ;
  • 조정래 (한국폴리텍VI대학 달성캠퍼스 자동차과)
  • Received : 2011.02.07
  • Accepted : 2011.08.08
  • Published : 2011.08.31

Abstract

In this paper, the influence of a crack on the natural frequency of cracked cantilever L-shaped beam with coupled bending and torsional vibrations by analytically and experimentally is analyzed. The L-shaped beam with a crack is modeled by Hamilton's principle with consideration of bending and torsional energy. The two coupled governing differential equations are reduced to one sixth-order ordinary differential equation in terms of the flexural displacement. The crack is assumed to be in the first, second and third mode of fracture and to be always opened during the vibrations. The theoretical results are validated by a comparison with experimental measurements. The maximal difference between the theoretical results and experimental measurements of the natural frequency is less than 7.5% in the second vibration mode.

Keywords

References

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