Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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Forced Vibration Modeling of Rail Considering Shear Deformation and Moving Magnetic Load

전단변형과 시간변화 이동자기력을 고려한 레일의 강제진동모델링

  • 김준수 (한양대학교 기계공학부) ;
  • 김성종 (한양대학교 기계공학부) ;
  • 이혁 (한양대학교 기계공학부) ;
  • 하성규 (한양대학교 기계공학부) ;
  • 이영현 (국방과학연구소)
  • Received : 2013.06.07
  • Accepted : 2013.09.27
  • Published : 2013.12.01
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Abstract

A forced vibration model of a rail system was established using the Timoshenko beam theory to determine the dynamic response of a rail under time-varying load considering the damping effect and stiffness of the elastic foundation. By using a Fourier series and a numerical method, the critical velocity and dynamic response of the rail were obtained. The forced vibration model was verified by using FEM and Euler beam theory. The permanent deformation of the rail was predicted based on the forced vibration model. The permanent deformation and wear were observed through the experiment. Parametric studies were then conducted to investigate the effect of five design factors, i.e., rail cross-section shape, rail material density, rail material stiffness, containment stiffness, and damping coefficient between rail and containment, on four performance indices of the rail, i.e., critical velocity, maximum deflection, maximum longitudinal stress, and maximum shear stress.

시간변화 이동자기력이 작용하는 레일의 변형을 티모센코 보 이론(Timoshenko beam theory)로 가정하였으며, 보의 진동특성에 영향을 미치는 탄성체기초의 감쇠효과 및 강성을 고려하였다. 푸리에 급수와 수치해석을 이용해 강제진동모델의 동적응답과 임계속도를 구하였다. 레일의 진동모델을 유한요소 해석 및 오일러 보 이론(Euler beam theory)과 비교 검증하였다. 강제진동모델을 이용하여 레일의 영구변형을 예측하였으며, 실험결과 레일표면의 영구변형 및 마모를 확인하였다. 보의 설계변수인 레일의 형상, 재료, 탄성체 기초의 감쇠효과 및 강성이 레일의 임계속도 및 레일의 처짐, 축 방향 응력, 전단 응력에 미치는 영향에 대한 매개변수적 연구를 진행하였으며, 보의 설계방향을 얻을 수 있었다.

Keywords

References

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