STress intensity factors for complex-cracked pipes based on elastic finite element analyses

Jae Uk Jeong, Jae Boong Choi, Nam Su Huh, Yun-Jae Kim

Research output: Chapter in Book/Report/Conference proceedingConference contribution


A complex crack is one of severe crack that can occur at the dissimilar metal weld of nuclear piping. A relevant fracture mechanics assessment for a pipe with a complex crack has become interested in structural integrity of nuclear piping. A stress intensity factor is not only an important parameter in the linear elastic fracture mechanics to predict the stress state at the crack tip, but also one of variables to calculate the J-integral in the elastic plastic fracture mechanics. The accurate calculation of stress intensity factor is required for integrity assessment of nuclear piping system based on Leak-Before-Break concept. In the present paper, stress intensity factors of complexcracked pipes were calculated by using detailed 3-dimensional finite element analysis. As loading conditions, global bending, axial tension and internal pressure were considered. Based on the present FE works, the values of shape factors for stress intensity factor of complex-cracked pipes are suggested according to a variables change of complex crack geometries and pipes size. Furthermore, the closed-form expressions based on correction factor are newly suggested as a function of geometric variables. These new solutions can be used to Leak- Before-Break evaluation for complex-cracked pipes in the step of elastic J calculation.

Original languageEnglish
Title of host publicationMaterials and Fabrication
PublisherAmerican Society of Mechanical Engineers (ASME)
ISBN (Electronic)9780791856994, 9780791856994, 9780791856994, 9780791856994
Publication statusPublished - 2015
EventASME 2015 Pressure Vessels and Piping Conference, PVP 2015 - Boston, United States
Duration: 2015 Jul 192015 Jul 23


OtherASME 2015 Pressure Vessels and Piping Conference, PVP 2015
CountryUnited States


ASJC Scopus subject areas

  • Mechanical Engineering

Cite this

Jeong, J. U., Choi, J. B., Huh, N. S., & Kim, Y-J. (2015). STress intensity factors for complex-cracked pipes based on elastic finite element analyses. In Materials and Fabrication (Vol. 6A-2015). American Society of Mechanical Engineers (ASME).