Flaw Assessment on an Offshore Structure using Engineering Criticality Analysis

ECA 기법을 이용한 해양구조물의 결함 평가

Kang, Beom-Jun;Kim, Yooil;Ryu, Cheol-Ho;Ki, Hyeok-Geun;Park, Sung-Gun;Oh, Yeong-Tae

  • Received : 2015.05.26
  • Accepted : 2015.11.18
  • Published : 2015.12.20


Offshore structure may be considerably vulnerable to fatigue failure while initial flaw propagates under cyclic loading, so crack propagation analysis/fracture/yield assessments about initial flaw detected by NDT are necessarily required. In this paper, case studies have been conducted by flaw assessment program using engineering criticality analysis (ECA) approach. Variables such as flaw geometry, flaw size, structure geometry, dynamic stress, static stress, toughness, crack growth rate, stress concentration factor (SCF) affected by weld are considered as analysis conditions. As a result, the safety of structure was examined during fatigue loading life. Also, critical initial flaw size was calculated by sensitivity module in the developed program. The flaw assessments analysis using ECA approach can be very useful in offshore industries owing to the increasing demand on the engineering criticality analysis of potential initial flaws.


Flaw assessment;Fracture mechanics;Crack propagation analysis;Initial flaw;BS7910


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Grant : 해양플랜트 특성화대학