말단질량을 갖는 테이퍼 원형강관 캔틸레버 보의 균열탐지기법

Lee, Jong-Won

  • 투고 : 2015.12.29
  • 심사 : 2016.03.29
  • 발행 : 2016.04.30


A crack identification method using the change of natural frequencies for tapered cantilever pipe-type cracked beam is presented. Modal properties of tapered cantilever intact beam with a tip mass are identified by applying the boundary conditions to a general solution. An equivalent bending stiffness for cracked beam based on an energy method is used to identify natural frequencies of tapered cantilever thin-walled pipe with a tip mass, which has a through-the-thickness crack, subjected to bending. The identified natural frequencies of the cracked beam are used in constructing training patterns of neural networks. Then crack location and size are identified using a committee of the neural networks. Crack detection was carried out for an example tapered beam using the proposed method, and the identified crack locations and sizes agree reasonably well with the exact values.


균열추정;말단질량;고유주파수;군집신경망;테이퍼 캔틸레버 보


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