Fatigue Fracture Analysis of Curved Pipes Under Cyclic Loading

Jang Heung Woon; Jung Jae-Wook; Hong Jung-Wuk

doi:10.7734/COSEIK.2016.29.4.363

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2016 Vol.29, Issue 4 Preview Page

Fatigue Fracture Analysis of Curved Pipes Under Cyclic Loading 반복 하중에 의한 곡관의 피로 균열 해석

2016. pp. 363-368

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Abstract

In this study, we numerically analyze fatigue cracks of curved pipes under cyclic loadings. Numerical models of the curved pipes are developed. The models are verified with the experimental results in terms of fatigue lives and development process of the fatigue cracks. Erosion technique is applied to the solid elements in order to describe shapes of the fatigue cracks and estimate the fatigue lives. Also, development of the fatigue cracks is described by allocating sufficient number of solid elements in the radial direction. Fatigue lives and shapes of the crack resulting from numerical analyses show good agreement with those of the experiment considering ±100mm displacement. In addition, estimation of the fatigue life caused by displacement with different magnitude is conducted. We expect that the model can be applied to understand the relation between fatigue lives and characteristics of pipes or loadings.

본 연구에서는 수치해석을 통하여 반복하중으로 인해 곡관에 형성되는 피로균열에 대한 분석을 수행하였다. 곡관의 수치해석 모델을 개발하였으며, 균열 형성 시점과 형성 과정에 기초하여 수치해석 모델을 검증하였다. 요소에 erosion 기능을 적용하여 피로균열을 표현하고 형성 시점을 추정하고자 하였으며, 두께방향으로 다수의 요소를 배치하여 균열의 형성 과정 또한 모사하고자 하였다. 100 mm 변위에 대한 실험결과와 비교하여 균열의 형성 시점 및 형상이 잘 일치하는 것을 확인하였으며, 추가적인 다른 변위에 대한 균열의 형성 시점 또한 예측하였다. 본 모델을 사용하여 다양한 형태의 하중에 대해 해석을 수행한다면 곡관의 형상 및 특성에 따른 하중과 균열 형성시점의 관계를 예측할 수 있을 것으로 기대된다.

Keywords

curved pipe, fatigue crack, cyclic loading, finite element method

곡관, 피로 균열, 반복 하중, finite element mothod

References

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Information

Publisher :Computational Structural Engineering Institute of Korea
Publisher(Ko) :한국전산구조공학회
Journal Title :Journal of the Computational Structural Engineering Institute of Korea
Journal Title(Ko) :한국전산구조공학회 논문집
Volume : 29
No :4
Pages :363-368
Received Date : 2016-06-27
Revised Date : 2016-08-16
Accepted Date : 2016-08-18
DOI :https://doi.org/10.7734/COSEIK.2016.29.4.363

Journal of the Computational Structural Engineering Institute of Korea ISSN:1229-3059(Print) 2287-2302(Online) 한국전산구조공학회 논문집

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