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Dispersive bending waves in uniform bars

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Abstract

The traveling bending waves in a long beam of rectangular cross section were measured and calculated. The bending waves were induced by impacting with a steel sphere and measured with strain gages at several distances from the point of impact. The impact force was calculated as a function of time by integrating the dynamic equations of the sphere and the beam. The force spectrum was then found using a fast-Fourier-transform (FFT) calculation and multiplied by the moment-frequency response of the beam to determine the moment spectrum. The moment-time function was calculated by an inverse FFT. The traveling wave is dispersive; its spectrum was found from that at the point of impact by phase shifting each component by an angle proportional to the distance and to the square root of the frequency. Again the time curve was determined by an inverse FFT. The indentation stiffness of the beam was found to be very much less than that of the elastic half space because of transverse bending. After the impact force was recalculated with this correction, the calculated moment-time traces agreed very well with the measured ones.

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References

  1. Havelock, T.H., “The Propagation of Disturbances in Dispersive Media,” Stechert-Hafner Service Agency (1964), (originally Cambridge University Press, 1914).

  2. Goldsmith, W., “Impact,” Edward Arnold, Sects. 4.6 and 6.4 (1960).

  3. Dohrenwendt, C.O., Drucker, D.C. andMoore, P., “Transverse Impact Transients,”Proc. SESA,1,2 (1944).

    Google Scholar 

  4. Ashwell, D.G., “The Anticlastic Curvature of Rectangular Beams and Plates,”J. Roy. Aero. Soc.,54,708–715 (1950).

    Google Scholar 

  5. Newland, D.E., “Random Vibration and Spectral Analysis,”Longman, London (1975).

    Google Scholar 

  6. Schwieger, H., “Central Deflection of a Transversely Struck Beam,”Experimenial Mechanics,10 (4),166–169 (April 1970).

    Google Scholar 

  7. Doyle, J.F., “Experimental Method for Determining the Dynamic-Contact Law,”Experimenial Mechanics,24 (1),10–15 (March 1984).

    Google Scholar 

  8. Cremer, L., Heckl, M. andUngar, E.E., “Structure-Borne Sound,”Ch. IV, Sect. 3(d), Springer-Verlag, New York (1973).

    Google Scholar 

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Authors and Affiliations

  1. Department of Aerospace Engineering and Mechanics, University of Minnesota, 107 Akerman Hall, 110 Union Street S.E., 55455, Minneapolis, MN

    A. K. Roy (Graduate Student) & R. Plunkett (SEM Member) is Professor)

Authors
  1. A. K. Roy
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  2. R. Plunkett
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Roy, A.K., Plunkett, R. Dispersive bending waves in uniform bars. Experimental Mechanics 25, 308–311 (1985). https://doi.org/10.1007/BF02325102

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  • DOI: https://doi.org/10.1007/BF02325102

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