THE DYNAMIC STABILITY OF HEAVY VEHICLE COMBINATIONS

The object of the investigation was to develop criteria suitable for regulations on the dynamic stability of heavy vehicle combinations. Demands for type approval are proposed in this paper. A double lane change manoeuvre was chosen as critical for evaluating the dynamic behaviour. The investigation included digital computer simulations and full scale field tests. The field tests recordings are used for validation of the simulation model. For the evaluation the following risk variables are chosen: 1) The slip angle maximum for each axle, 2)The lateral deviation maximum for each axle, and 3) The overturning risk maximum for each axle or vehicle unit. The simulation results show the influence from speed and from a number of vehcile parameters. They are also used for comparing different types of combinations. The dynamic behaviour of the tractor + semitrailer + full trailer combination is found to be speed dependent and inferior to comparable truck + full trailer and tractor + semitrailer combinations. The double lane change is proposed as a test procedure for the dynamic stability of heavy vehicle combinations. The manoeuvre should be performed at 70 km/h with full land, and maximum allowed center of gravity height. Certain maximum values on the mentioned risk variables must not be exceeded for approval. The problem of off- tracking towards the outside of a curve due to the side slip angles is also discussed, and a steady state test is proposed to assure that this off- tracking is kept within safe limits. In addition to these studies a full scale investigation was made of the static overturning stability of some heavy tracks, tractor + semitrailers and full trailers at maximum allowed weight and varying centre of gravity height. As a result of this investigation a full scale static overturning stability test is proposed.

  • Supplemental Notes:
    • This paper was presented at the Third International Conference of Vehicle Systems Dynamics, Blacksburg, Va. August 12-15, 1974
  • Corporate Authors:

    Swedish National Road and Transport Research Institute (VTI)

    Linköping,   Sweden  SE-581 95
  • Authors:
    • Nordstrom, O
    • STRANDBERG, L
  • Publication Date: 1975

Media Info

  • Features: Figures; References; Tables;
  • Pagination: 43 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00150435
  • Record Type: Publication
  • Report/Paper Numbers: Report No. 67A
  • Files: TRIS, ATRI
  • Created Date: Apr 27 1977 12:00AM