0
Research Papers

Parametric Analyses of Multispan Viscoelastic Shear Deformable Beams Under Excitation of a Moving Mass

[+] Author and Article Information
Keivan Kiani1

Department of Civil Engineering, Sharif University of Technology, Azadi Ave., Tehran, Iran, P.O. Box 11365-9313k_kiani@civil.sharif.edu

Ali Nikkhoo

Department of Civil Engineering, Sharif University of Technology, Azadi Ave., Tehran, Iran, P.O. Box 11365-9313nikkhoo@civil.sharif.edu

Bahman Mehri

Department of Mathematical Sciences, Sharif University of Technology, Tehran, Iran 11365-9415mehri@sharif.edu

1

Corresponding author.

J. Vib. Acoust 131(5), 051009 (Sep 16, 2009) (12 pages) doi:10.1115/1.3147165 History: Received November 01, 2008; Revised April 10, 2009; Published September 16, 2009

This paper presents a numerical parametric study on design parameters of multispan viscoelastic shear deformable beams subjected to a moving mass via generalized moving least squares method (GMLSM). For utilizing Lagrange’s equations, the unknown parameters of the problem are stated in terms of GMLSM shape functions and the generalized Newmark-β scheme is applied for solving the discrete equations of motion in time domain. The effects of moving mass weight and velocity, material relaxation rate, slenderness, and span number of the beam on the design parameters and possibility of mass separation from the base beam are scrutinized in some detail. The results reveal that for low values of beam slenderness, the Euler–Bernoulli beam theory or even Timoshenko beam theory could not predict the real dynamic behavior of the multispan viscoelastic beam properly. Moreover, higher beam span number would result in higher inertial effects as well as design parameters values. Also, more distinction has been observed between the predicted values of design parameters regarding the shear deformable beams and those of Euler–Bernoulli beams, specifically for high levels of moving mass velocity and low values of material relaxation rate. Furthermore, the possibility of mass separation from the base beam moves to a greater extent as the beam span number increases and the relaxation rate of the beam material decreases, regardless of the assumed beam theory.

FIGURES IN THIS ARTICLE
<>
Copyright © 2009 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

Schematic representation of a multispan viscoelastic shear deformable beam subjected to a moving mass

Grahic Jump Location
Figure 2

Variation in the normalized design parameters in terms of span number for λx=λz=0.00001: (a) λ=10, (b) λ=20, and (c) λ=40 ((◻) VN=0.2, (◇) VN=0.5, and (△) VN=0.8; (…) EBT, (− −) TBT, and (—) HOBT; MN=0.15)

Grahic Jump Location
Figure 3

Variation in the normalized design parameters in terms of span number for λx=λz=0.0001: (a) λ=10, (b) λ=20, and (c) λ=40 ((◻) VN=0.2, (◇) VN=0.5, and (△) VN=0.8; (…) EBT,(− −) TBT, and (—) HOBT; MN=0.15)

Grahic Jump Location
Figure 4

Variation in the normalized design parameters in terms of span number for λx=λz=0.001: (a) λ=10, (b) λ=20, and (c) λ=40 ((◻) VN=0.2, (◇) VN=0.5, and (△) VN=0.8; (…) EBT,(− −)TBT, and (—) HOBT; MN=0.15)

Grahic Jump Location
Figure 5

Variation in the normalized design parameters in terms of span number for λx=λz=0.01: (a) λ=10, (b) λ=20, and (c) λ=40 ((◻) VN=0.2, (◇) VN=0.5, and (△) VN=0.8; (…) EBT, (− −) TBT, and (—) HOBT; MN=0.15)

Grahic Jump Location
Figure 6

Variation in the normalized values of minimum and maximum contact forces in terms of span number for λx=λz=0.00001: (a) λ=10, (b) λ=20, and (c) λ=40 ((◻) VN=0.2, (◇) VN=0.5, and (△) VN=0.8; (…) EBT, (− −) TBT, and (—) HOBT; MN=0.15)

Grahic Jump Location
Figure 7

Variation in the normalized values of minimum and maximum contact forces in terms of span number for λx=λz=0.0001: (a) λ=10, (b) λ=20, and (c) λ=40 ((◻) VN=0.2, (◇) VN=0.5, and (△) VN=0.8; (…) EBT, (− −) TBT, and (—) HOBT; MN=0.15)

Grahic Jump Location
Figure 8

Variation in the normalized values of minimum and maximum contact forces in terms of span number for λx=λz=0.001: (a) λ=10, (b) λ=20, and (c) λ=40 ((◻) VN=0.2, (◇) VN=0.5, (△) VN=0.8; (…) EBT, (− −) TBT, and (—) HOBT; MN=0.15)

Grahic Jump Location
Figure 9

Variation in the normalized values of minimum and maximum contact forces in terms of span number for λx=λz=0.01: (a) λ=10, (b) λ=20, and (c) λ=40 ((◻) VN=0.2, (◇) VN=0.5, (△) VN=0.8; (…) EBT, (− −) TBT, and (— ) HOBT; MN=0.15)

Grahic Jump Location
Figure 10

Variation in the normalized design parameters in terms of span number based on EBT for λ=40 and λx=0.00001: (a) VN=0.2, (b) VN=0.5, and (c) VN=0.8 ((◻) MN=0.1, (◇) MN=0.2, (△) MN=0.3, and (○) MN=0.4; (− −) moving load and (—) moving mass)

Grahic Jump Location
Figure 11

Variation in the normalized design parameters in terms of span number based on TBT for λ=20 and λx=λz=0.00001: (a) VN=0.2, (b) VN=0.5, and (c) VN=0.8 ((◻) MN=0.1, (◇) MN=0.2, (△) MN=0.3, and (○) MN=0.4; (− −) moving load and (—) moving mass)

Grahic Jump Location
Figure 12

Variation in the normalized design parameters in terms of span number based on HOBT for λ=10 and λx=λz=0.00001: (a) VN=0.2, (b) VN=0.5, and (c) VN=0.8 ((◻) MN=0.1, (◇) MN=0.2, (△) MN=0.3, and (○) MN=0.4; (− −) moving load and (—) moving mass)

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In