Abstract

In this paper, the estimation method of C(t)-integral for combined mechanical and thermal loads is proposed for elastic-plastic-creep material via 3-dimensional FE analyses. Plasticity induced by initial loading makes relaxation rate different from those produced elastically. Moreover, the interactions between mechanical and thermal loads make the relaxation rate different from those produced under mechanical load alone. To quantify C(t)-integral for combined mechanical and thermal loads, the simplified formula are developed by modifying redistribution time in existing work done by Ainsworth et al..

Keywords

• C(t)-Integral;
• Crack;
• Transient Creep Condition;
• Combined Mechanical and Thermal Stress;
• Elastic Plastic Creep

• C(t)-적분;
• 균열;
• 천이 크리프 조건;
• 기계응력 및 열응력의 복합응력;
• 탄소성 크리프;

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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. Estimation of C(t)-Integral in Transient Creep Condition for Pipe with Crack Under Combined Mechanical and Thermal Stress (II) - Elastic-Plastic-Creep - vol.33, pp.10, 2009, https://doi.org/10.3795/KSME-A.2009.33.10.1065