• 제목/요약/키워드: Stress-life relations or S-N curve

검색결과 2건 처리시간 0.018초

누적손상법(Miner's rule)을 이용한 철도차량 차체 용접부의 피로평가 (The fatigue analysis using cumulative damage rule (Miner's rule) for the welding areas of carbody structure)

  • 김광우;박근수;박형순
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2007년도 추계학술대회 논문집
    • /
    • pp.30-34
    • /
    • 2007
  • Structural integrity of railway vehicles should last for a long period against various and continuous fatigue loadings, and the carbody structures of railway vehicle are manufactured by applying multiform welding types for each material. Since the most of cracks are occurred and proceeded at the vicinity of welding area during the lifetime of carbody structure, the fatigue strength evaluation for welding area of carbody structure should have been carried out. Rotem Company has evaluated lifetime and fatigue strength of carbody structure according to the fatigue analysis based on the international standard and/or inner-official regulation. This study introduces the fatigue analysis method that we have evaluated and calculated the damages for the welding areas of carbody structure under various fatigue loading conditions using cumulative fatigue damage rule(Miner's rule) to verify whether the cumulative damage does exceed unity. This study contains the fatigue test of specimens to derive stress-life relations(S-N curve), sub-modeling analysis and the calculation of cumulative damages under fatigue loading. The fatigue analysis verifies the welding area shall be capable of withstanding under fatigue loading, identifies how critical area shall be selected and presents the principles to be used for design verification.

  • PDF

Fatigue behavior of circular hollow tube and wood filled circular hollow steel tube

  • Malagi, Ravindra R.;Danawade, Bharatesh A.
    • Steel and Composite Structures
    • /
    • 제19권3호
    • /
    • pp.585-599
    • /
    • 2015
  • This paper presents the experimental work on fatigue life and specific fatigue strength of circular hollow sectioned steel tube and wood filled circular hollow section steel tube. Burning effect was observed in the case of circular hollow sectioned steel tube when it is subjected to Maximum bending moment of 19613.30 N-mm at 4200 rpm, but this did not happen in the case of wood filled hollow section. Statistical analysis was done based on the experimental data and relations have been built to predict the number of cycles for the applied stress or vice versa. The relations built in this paper can safely be applied for design of the fatigue life or fatigue strength of circular hollow sections and wood filled hollow sections. Results were validated by static specific bending strengths determined by ANSYS using a known applied load.