The Evaluation of LBB Behavior and Crack Opening Displacement on Piping System under Bending Load

굽힘하중을 받는 배관계의 LBB거동 및 균열개구변위의 평가

The LBB behavior and the crack opening displacement after a crack penetrated wall thickness of statically indeterminate piping system were investigated in this study, compared with statically determinate piping system. The reduction of ultimate strength caused by a crack was relatively small in the statically indeterminate piping system. The statically indeterminate piping system has more safety margin for LBB behavior than the statically determinate piping system. The crack opening displacement could be evaluated by using the plastic rotation angle proposed to evaluate the crack opening displacement after crack penetration in pipe with a non-penetrating crack.