Crack identification method for tapered cantilever pipe-type beam using natural frequencies

A method to detect location and size of a crack in tapered cantilever pipe-type beam using changes in natural frequencies is presented. The boundary conditions of cantilever beam are applied to a general solution for vibrating tapered beam. Then, an equivalent bending stiffness for cracked beam is used to obtain the natural frequencies. Numerical simulations are carried out to construct a set of training patterns of a neural network, and committee of neural networks is employed to identify the crack. Crack identifications are carried out for the 16 damage cases numerically and for the 3 damage cases experimentally. The identified crack locations and sizes agree reasonably well with the exact values.

[1]  S. K. Maiti,et al.  Frequency-based experimental and theoretical identification of multiple cracks in straight pipes filled with fluid , 2004 .

[2]  S. K. Maiti,et al.  On prediction of crack in different orientations in pipe using frequency based approach , 2008 .

[3]  D. J. Gorman.  Free vibration analysis of beams and shafts , 1975 .

[4]  M. Lippiello,et al.  Free vibration of elastically restrained cantilever tapered beams with concentrated viscous damping and mass , 2010 .

[5]  M. Chapetti,et al.  On the detection threshold for fatigue cracks in welded steel beams using vibration analysis , 2011 .

[6]  Zhengjia He,et al.  Pipe crack identification based on finite element method of second generation wavelets , 2010 .

[7]  S. Loutridis,et al.  Forced vibration behaviour and crack detection of cracked beams using instantaneous frequency , 2005 .

[8]  Zhengjia He,et al.  Daubechies wavelet finite element method and genetic algorithm for detection of pipe crack , 2011 .

[9]  Jong-Won Lee,et al.  Damage detection method for large structures using static and dynamic strain data from distributed fiber optic sensor , 2010 .

[10]  Khoa Viet Nguyen,et al.  Multi-cracks detection of a beam-like structure based on the on-vehicle vibration signal and wavelet analysis , 2010 .

[11]  Mehmet Cem Ece,et al.  Vibration of a variable cross-section beam , 2007 .

[12]  A. Morassi,et al.  Detecting cracks in pipes filled with fluid from changes in natural frequencies , 2011 .

[13]  A. S. J. Swamidas,et al.  Crack identification in vibrating beams using the energy method , 2001 .

[14]  Young-Cheol Huh,et al.  Pipe crack identification based on the energy method and committee of neural networks , 2014 .

[15]  N. M. Auciello,et al.  VIBRATIONS OF A CANTILEVER TAPERED BEAM WITH VARYING SECTION PROPERTIES AND CARRYING A MASS AT THE FREE END , 1998 .

[16]  Kiyotoshi Matsuoka,et al.  Noise injection into inputs in back-propagation learning , 1992, IEEE Trans. Syst. Man Cybern..

[17]  Chih-Chieh Chang,et al.  Vibration damage detection of a Timoshenko beam by spatial wavelet based approach , 2003 .

[18]  E. Carrera,et al.  Free vibration of tapered beams and plates based on unified beam theory , 2014 .

[19]  Martin Veidt,et al.  Experimental characterization of multiple cracks in a cantilever beam utilizing transient vibration data following a probabilistic approach , 2007 .