Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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Estimations of the C(t)-Integral in Transient Creep Condition for Pipe with Crack Under Combined Mechanical and Thermal Stress (I) - Elastic-Creep -

복합응력이 작용하는 균열 배관에 대한 천이 크리프 조건에서의 C(t)-적분 예측 (I) - 탄성-크리프 -

  • Published : 2009.09.01
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Abstract

The C(t)-integral describes amplitude of stress and strain rate field near a tip of stationary crack under transient creep condition. Thus the C(t)-integral is a key parameter for the high-temperature crack assessment. Estimation formulae for C(t)-integral of the cracked component operating under mechanical load alone have been provided for decades. However, high temperature structures usually work under combined mechanical and thermal load. And no investigation has provided quantitative estimates for the C(t)-integral under combined mechanical and thermal load. In this study, 3-dimensional finite element analyses were conducted to calculate the C(t)-integral of elastic-creep material under combined mechanical and thermal load. As a result, redistribution time for the crack under combined mechanical and thermal load is re-defined through FE analyses to quantify the C(t)-integral. Estimates of C(t)-integral using this proposed redistribution time agree well with FE analyses results.

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References

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  1. Estimation of C(t) -Integral Under Transient Creep Conditions for a Cracked Pipe Subjected to Combined Mechanical and Thermal Loads Depending on Loading Conditions vol.35, pp.6, 2011, https://doi.org/10.3795/KSME-A.2011.35.6.609
  2. Estimations of the C(t)-Integral in Transient Creep Condition for Pipe with Crack Under Combined Mechanical and Thermal Stress (I) - Elastic-Creep - vol.33, pp.9, 2009, https://doi.org/10.3795/KSME-A.2009.33.9.949