Abstract

In order to analyze the elastic-plastic fracture behavior of a structure, the fracture resistance curve of the material should be known first. The standard CT specimen was used to obtain the fracture resistance curves of a piping system. However, it is known that the fracture resistance curve by the standard CT specimen is very conservative to evaluate the integrity of a structure. Also the fracture resistance curve is effected by the specimen geometry and the dimensions because of the constraint effect. The objective of this paper is to be certain the conservativeness of the fracture resistance curve by the standard CT specimen and to provide an additional safety margin. For these, the fracture tests using a real pipe specimen and the standard CT specimen test were performed. A 4-point bending jig was manufactured for the pipe test and the direct current potential drop method was used to measure the crack extension and the length for the pipe test. Also finite element analyses were performed with a CT specimen and a pipe in order to prove the additional safety margin. From the result of tests and analyses of the pipe and the standard CT specimen, it was observed that the fracture analysis with the standard CT specimen is conservative and the additional safety margin was proved.

주제어

#파괴특성   #4점굽힘시험   #구속효과   #파괴저항곡선   #J-Q 해석  

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참고문헌 (11)

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이 논문을 인용한 문헌 (2)

1. Shin, In Hwan ; Park, Chi Yong ; Seok, Chang Sung ; Koo, Jae Mean 2014. "Evaluation of Shape Parameter Effect on the J-R Curve of Curved CT Specimen Using Limit Load Method" 大韓機械學會論文集. Transactions of the Korean Society of Mechanical Engineers. A. A, 38(7): 757~764  원문보기 상세보기
2. 2015. "" International journal of precision engineering and manufacturing, 16(1): 65~71  상세보기