DYNAMIC STABILITY OF A BEAM LOADED BY A SEQUENCE OF MOVING, MULTI-AXLE, MASS VEHICLES

An approximate method is presented for determining the dynamic stability of the lateral response for a finite Bernoulli-Euler beam loaded by a continuous sequence of vehicles traveling at a constant speed. The beam, which can also be loaded by a constant axial force, is uniform and simply supported and rests on a massless, uniform elastic foundation. Damping for the beam and foundation is provided by a combined uniform viscous damping coefficient. The vehicles which are identical, equally spaced, and attached to the beam, each consist of a rigid body mass supported by two separate axles or wheel masses. Consequently, the vehicles can rotate (or pitch) and translate laterally. The Galerkin method is used to generate a set of approximate equations of motion which contain periodic coefficients. Hence, multiple regions of dynamic instability can occur. The coupled equations are simplified by using a one-term Galerkin approximation which, under certain conditions, reduces to a Mathieu equation. Thus, the critical vehicle speeds, which correspond to dynamic instability, are predicted in terms of the physical system parameters by simple algebraic expressions.

• Corporate Authors:

  International Society for Terrain-Vehicle Systems

  Box 4824, Duke Station
  Durham, NC  United States  27706

  Planning Transport Associates, Incorporated

  P.O. Box 4824, Duke Station
  Durham, NC  United States  27706
• Authors:
  • Benedetti, G A
• Publication Date: 1975-3

Media Info

• Features: References;
• Pagination: p. 483-493
• Serial:
  • High Speed Ground Transportation Journal
  • Volume: 9
  • Issue Number: 1

Subject/Index Terms

• TRT Terms: Beams; Bridges; Elevated guideways; Stresses
• Old TRIS Terms: Bridge stresses
• Subject Areas: Bridges and other structures; Railroads;

Filing Info

• Accession Number: 00083907
• Record Type: Publication
• Source Agency: Engineering Index
• Files: TRIS
• Created Date: May 1 1975 12:00AM