Evaluation of Rail Fatigue Life by Grinding of Kyeong-Bu High-Speed Line

경부고속선의 레일 연마에 따른 레일 피로수명 평가

  • 김만철 (한국철도기술연구원 차륜궤도연구실) ;
  • 최은수 (홍익대학교 토목공학과)
  • Received : 2010.07.26
  • Accepted : 2010.11.08
  • Published : 2010.12.06

Abstract

The importance of maintenance of rail surface defects is increasing according to the KTX operation. That is because during high speed operation of rolling stocks, rail surface defects shorten fatigue life of rail, accelerate track degradation and deteriorate ride comfort. Rail grinding has been applied for effective rail maintenance in Kyeong-Bu HS line. This paper evaluates the effectiveness of rail grinding in term of rail fatigue life. To this end, the stresses of the rail are measured under KTX running and the equivalent stress range is calculated by RMC after the frequency analysis done with rainflow counting method. Also, The Modified Miner's rule is applied to predict the fatigue life of ground rail. The result of the analysis shows that the fatigue life of ground rail is increased by 15%.

고속철도 운행에 따라 레일표면결함에 대한 관리의 중요성이 점점 더 증대되고 있다. 차량의 고속주행시 레일표면결함은 레일의 피로수명 단축 및 궤도의 열화 촉진, 승차감 저하를 유발하기 때문이다. 현재 경부고속철도에서는 레일의 효율적 유지보수를 위하여 레일연마를 수행하고 있다. 본 논문에서는 레일연마에 따른 레일의 피로수명을 예측하였다. 이를 위해서 연마 후 KTX 운행시 레일 저부의 휨응력을 계측하였으며, Rain-flow counting 기법을 적용하여 빈도해석을 실시하여 RCM에 의해 등가응력범위를 산정하였다. 선형누적피로피해를 이용한 피로수명 평가방법은 수정 Miner 법칙에 기초하였다. 해석결과 연마에 따른 레일의 피로수명이 15% 증가되는 것으로 나타났다.

Keywords

References

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