It is important to accurately predict natural frequencies of a cracked beam for damage assessment. The damage can be confirmed through the comparison of the natural frequencies of an intact beam to those of a target beam. This study formulates the natural frequencies of a cracked beam from wave propagation perspective. This formulation results in an explicit characteristic equation with respect to wave number through neglecting the evanescent wave modes traveling from long distance. The proposed method is validated through an numerical example in which several natural frequencies computed by the proposed method and finite element analysis are compared one after another.

• 강지강(동아대학교 토목공학과, 석사과정) | Kang Ji Kang
• 박현우(동아대학교 인간환경융합공학부 토목공학과 교수, 공학박사) | Park Hyun Woo 교신저자