MODERN APPROACHES TO SOLUTION OF THE WIND PROBLEMS OF LONG SPAN BRIDGES

The state of the art of the aerodynamic and aeroelastic problems of long supended-span bridges is briefly reviewed with particular reference to earlier work by Tomko and the author. Aerodynamic studies are described which are performed by the cheap and convient desk section model. The results from this which will then be applied to the full prototype bridge. The bridge section model is most valuable for its geometric fidelity rather than for its other scaling parameters. The study found that bridge decks have aerodynamic stability derivatives which differ from comparable results for airfoils. Therefore, use of airfoil flutter derivatives for bridges flutter analysis is incorrect. The method of exploiting the section model uniquely for its geometric properties frees the testing procedure from all similarity requirements other than geometric. The model thus becomes an analogue computer of dimensionless aerodynamic effects alone. The inexpensive freely oscillating model technique permits the intrinsically nonlinear aerodynamics of the situation to be quite reasonable linearized. Study findings are also presented which relate to: bridge structural frequencies, values of bridge mechanical damping, the fundamental torsional to bending frequencies, vortex-induced oscillation, and buffeting.

  • Availability:
  • Corporate Authors:

    American Institute of Steel Construction

    101 Park Avenue
    New York, NY  USA  10017
  • Authors:
    • Scanlan, R H
  • Publication Date: 1976-4

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 26-34
  • Serial:
    • Engineering Journal
    • Volume: 13
    • Issue Number: 2
    • Publisher: American Institute of Steel Construction
    • ISSN: 0013-8029

Subject/Index Terms

Filing Info

  • Accession Number: 00142986
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Dec 22 1976 12:00AM