Mechanism of Damping in Welded Structures using Finite Element Approach

The characterization and modeling of the dynamic behavior of many built-up structures under vibration conditions is still a subject of current research. The present study emphasizes the theoretical investigation of slip damping in layered and jointed welded cantilever structures using finite element approach. Application of finite element method in damping analysis is relatively recent, as such, some problems particularly slip damping analysis has not received enough attention. To validate the finite element model developed, experiments have been conducted on a number of mild steel specimens under different initial conditions of vibration. Finite element model developed affirms that the damping capacity of such structures is influenced by a number of vital parameters such as; pressure distribution, kinematic coefficient of friction and micro-slip at the interfaces, amplitude, frequency of vibration, length and thickness of the specimen. Finite element model developed can be utilized effectively in the design of machine tools, automobiles, aerodynamic and space structures, frames and machine members for enhancing their damping capacity.

Authors:

• B. Singh
• B. K. Nanda

Keywords:

• Amplitude
• finite element method
• slip damping
• tack welding.

References:

[1] B. M. Belgaumkar, and A. S. R. Murty, "Effect of root fixture conditions
on the damping characteristics of cantilever beam," Journal of science
and Engineering research, India, vol. 12, no.1, pp.147-154, 1968.
[2] M. Masuko, I. Yoshimi, and Y. Keizo, "Theoretical analysis for a
damping ration of a jointed cantibeam," Bull. JSME, vol. 16, no.99, pp.
1421-1433, 1973.
[3] N. Nishiwaki, M. Masuko, Y. Ito, and I. Okumura, "A study on damping
capacity of a jointed cantilever beam (1st report; experimental results),"
Bulletin of JSME, vol. 21, no. 153, pp. 524-531, 1978.
[4] B.P. Shastry, and G.V. Rao, "Dynamic stability of a cantilever column
with an intermediate concentrated periodic load," Journal of Sound and
Vibration, vol. 113, pp. 194 - 197, 1987.
[5] O.A. Bauchau, and C.H. Hong, "Nonlinear response and stability analysis
of beams using finite elements in time," AIAA Journal, vol. 26, pp. 1135-
1141, 1998.
[6] G. Briseghella, C.E. Majorana, and C. Pellegrino, "Dynamic stability of
elastic structures: a finite element approach," Computer and structures,
vol. 69, pp. 11-25, 1998.
[7] M. G. Sainsbury, and Q. J. Zhang, "The Galerkin Element Method
Applied to the Vibration of Damped Sandwich Beams," Computer and
structures, vol. 71, no. 3, pp. 239-256, 1999