Journal of Ocean Engineering and Technology (한국해양공학회지)

Korean Society of Ocean Engineers (한국해양공학회)
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Damage Detection in Jacket-Type Offshore Structures From Few Mode Shapes

소수의 모드형상을 이용한 자켓형 해양구조물의 손상추정에 대한 연구

  • Kim, Jeng-Tae (Postdoctoral Research Associate, Department of Civil Engineering, Texas AandM University, College Station, TX 77843 USA) ;
  • ;
  • Stubbs, Norris (Dept of Civil Engeering of Civil Engeering Texas AandM Univ)
  • Published : 1994.06.01
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Abstract

An algorithm to locate and estimate severity of damage in jacket-type offshore structures for which modal responses are availabit' for very few vibrational modes is presented. First, a theory of damage locaization and severity estimation(which yields information on the location and severity of damage directly from changes in mode shapes) is formulated. Next, the feasibility the damage detection algorithm is demonstrated by using a numerical example of an offshore jacket platform for which only three vibration modes are measured. Form the material presented here, two major results are observed. First, all damage locations in the offshore jacket platform are correctly predicted. Next, predicted damage is relatively correctly estimated.

본 연구에서는, 소수의 모드형상의 진동반응만이 측정된 자켓형 해양구조물에 존재하는 손상의 위치와 그 크기를 결정할 수 있는 알고리듬이 제시된다. 먼저, 모드형상의 변화로 부터 직접 손상위치와 크기를 결정하는 이론이 제시된다. 다음으로, 세개의 진동모드형상이 측정된 자켓형 해양구조물의 수치예를 이용하여 알고리듬의 적합성이 예증된다. 본 연구의 결과는 다음과 같다. 첫째로, 자켓형 해양구조물에 존재하는 손상의 위치가 정확하게 예측 되었다. 둘째로, 예측된 손상의 크기가 비교적 정확하게 예측되었다.

Keywords

References

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