Stress Concentration Factor and Stress Intensity Factor with U-notch and Crack in the Beam

U-노치 및 균열을 갖는 보의 응력집중계수 및 응력확대계수

  • Seo, Bo Seong (School of Automotive Engineering, Kyungpook Nat'l Univ.) ;
  • Lee, Kwang Ho (School of Automotive Engineering, Kyungpook Nat'l Univ.)
  • 서보성 (경북대학교 자동차공학부) ;
  • 이광호 (경북대학교 자동차공학부)
  • Received : 2016.02.16
  • Accepted : 2016.03.21
  • Published : 2016.05.01


The stress concentration factors and stress intensity factors for a simple beam and a cantilever are analyzed by using finite element method and phtoelasticity. Using the analyzed results, the estimated graphs on stress concentration factors and stress intensity factors are obtained. To analyze stress concentration factors of notch, the dimensionless notch length H(height of specimen)/h=1.1~2 and dimensionless gap space r(radius at the notch tip)/h=0.1~0.5 are used. where h=H-c and c is the notch length. As the notch gap length increases and the gap decreases, the stress concentration factors increase. Stress concentration factors of a simple beam are greater than those of a cantilever beam. However, actually, the maximum stress values under a load, a notch length and a gap occur more greatly in the cantilever beam than in the simple beam. To analyze stress intensity factors, the normalized crack length a(crack length)/H=0.2~0.5 is used. As the length of the crack increases, the normalized stress intensity factors increase. The stress intensity factors under a constant load and a crack length occur more greatly in the cantilever beam than in the simple beam.


Supported by : 한국연구재단


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