Session: CS-16-01 Fatigue and Ratcheting Issues in Pressure Vessel and Piping Design-1

Paper Number: 152796

152796 - Calculation Method of Cumulative Total Strain by Reversing Dynamic Load +Non Reversing Dynamic Load 

Abstract: 

In this paper, a strain-based damage evaluation method based on elastic-plastic analysis was examined for carbon steel piping elbows. In order to simulate the results of the fatigue tests on piping elbows(SE-1/SE-5/SE-7/SE-8) reported in the ‘NUPEC Piping System Ultimate Strength Test Program Report’, we carried out the strain-based damage evaluation by using elastic-plastic analysis. In the elastic-plastic analysis of the elbows, a hybrid model consisting of beam elements and shell elements was used, and the Chaboche/kinematic model was used to accurately simulate the cyclic hardening behavior of the material. The fatigue curve used for fatigue damage evaluation was the fatigue curve by ‘modified Manson universal slope method’. As a result, it was confirmed that there is possible that the fatigue test results of piping elbows reported in previous studies could be simulated by using the equivalent strain amplitude by elastic-plastic analysis, measured true fracture strain and the ‘modification method for fatigue life based on the ductile consumption law in multi-axial stress state’, proposed by Asada. Also, we proposed the ‘cumulative strain estimation method’ used in the ‘cumulative plastic damage evaluation for combination load of reversing dynamic load and non-reversing dynamic load’ in the ASME code case (CC N-900).

Presenting Author: Kenichi Shibukuwa IHI Corporation

Presenting Author Biography: Kenichi Shibukuwa is a manager at IHI Corporation in Japan. His work focuses specifically on management of maintenance and construction project for Domestic Nuclear Power Plant. He has a lot of expertise in the piping engineering of nuclear power plant for 36 years. Also, He has been active in JSME(The Japan Society of Mechanical Engineers) and JEA(The Japan Electric Association) as code engineer since 2020.

Authors:

Kenichi Shibukuwa IHI Corporation
Jie Wen JENSEN HUGHES