Study on the Axial Crushing Behaviors of UD Kevlar/Epoxy and Carbon-Kevlar/Epoxy Composite Tubes

단방향 케블라/에폭시, 탄소-케블라/에폭시 복합재 튜브의 축방향 압괴 거동에 대한 연구

  • 김형욱 (과학기술연합대학원대학교 가상공학과) ;
  • 김정석 (한국철도기술연구원 철도구조연구실) ;
  • 정현승 (한국철도기술연구원 철도구조연구실) ;
  • 윤혁진 (한국철도기술연구원 철도구조연구실) ;
  • 권태수 (한국철도기술연구원 정책전략연구실)
  • Received : 2010.04.06
  • Accepted : 2010.06.07
  • Published : 2010.06.26

Abstract

In this paper, a numerical model for a Kevlar/Epoxy and Carbon-Kevlar/Epoxy tube used as an energy absorbing component has been developed and then results have been verified through experiment. The 2D shell element and Chang-Chang failure criterion of LS-DYNA that is commercial explicit FE code was used. Mechanical material properties for the model were obtained by material testing in advance. The numerical results were compared with quasi-static test results under axial compressive loading at 10mm/min. From the results, in the case of the Kevlar/Epoxy tube, load-crushed displacement curves were very close to the experiments and SEA (specific energy absorption) shows a good agreement with experimental one within less than 6%. However, the Carbon-Kevlar/Epoxy tube shows some differences with the experimental results.

본 논문에서는 에너지 흡수부재로 사용될 수 있는 단방향 케블라/에폭시 및 단방향 탄소-케블라/에폭시 튜브의 압괴거동을 예측할 수 있는 해석모델을 확립하고 이를 시험을 통해 검증하였다. 해석모델은 상용 외연적 해석 프로그램인 LS-DYNA의 2D 쉘 요소와 Chang-Chang 파손기준식을 이용하였다. 또한, 해석에 적용된 소재의 기계적 물성치는 시험을 통해 얻었다. 해석모델은 원형 튜브에 대한 10mm/min의 준정적 압괴 시험 결과와 비교를 통해 검증하였다. 그 결과 케블라/에폭시 튜브의 하중-변위 곡선은 거의 일치했으며 무게당 흡수 에너지(SEA)도 6% 미만의 오차에서 잘 일치하였다. 하지만, 탄소-케블라/에폭시 튜브는 시험과 약간의 차이를 보이고 있다.

Keywords

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