Creep elastic follow-up factors under combined primary and secondary stresses

• Published in: The International journal of pressure vessels and piping Vol. 101; pp. 12 - 22
• Main Authors: Lee, Kuk-Hee, Kim, Yun-Jae, Jerng, Dong Wook, Ainsworth, Robert A., Dean, Dave
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.01.2013
• Subjects: Beam; Combined primary and secondary load; Creep (materials); Creep elastic follow-up factor; Mathematical analysis; Pipe; Piping; Plane strain; Pressure vessels; Stress relaxation; Stresses; Beam; Combined primary and secondary load; Pipe; Creep elastic follow-up factor
• ISSN: 0308-0161; 1879-3541
• DOI: 10.1016/j.ijpvp.2012.08.005

This paper presents elastic-creep finite element analyses for smooth and notched plane strain beams and axi-symmetric pipes subject to combined primary and secondary stresses. The relative magnitudes of the primary and secondary stresses are systematically varied. Elastic follow-up factors, which quantify the effect of the primary stress on creep relaxation behaviour of the secondary stress, are extracted as a function of the relative magnitude of the primary and secondary stresses. It is found that elastic follow-up factors due to the secondary stress are affected by the magnitude of the primary stress, and the presence of the primary stress can significantly increase elastic follow-up factors. ► Elastic follow-up factors for combined primary and secondary stresses are studied. ► Elastic follow-up factors are extracted from finite element results. ► Elastic follow-up factors are affected by the magnitude of the primary stress. ► The presence of the primary stress can significantly increase elastic follow-up factors.