RESEARCH PAYS OFF--STRENGTHENING OF HIGHWAY BRIDGES BY POSTTENSIONING

Approximately 400 simple-span, steel beam, composite concrete slab bridges built between 1940 and 1960 require strengthening to meet current standards, i.e. the live-load carrying capacity of the steel stringers of these bridges must be increased. Among the potential solutions to the problem, the procedure of posttensioning of the steel stringers appeared to exhibit the greatest promise. This article describes the research to determine the distribution characteristics of the posttensioning force in a multiple stringer bridge, the feasibility studies that were conducted, the finite element analysis, and the design methodology that was developed. The application of the procedure in several states is noted. The applications have led to savings, that in one instance, totalled $14,600. Larger savings would be realized on longer spans, inasmuch as replacement costs of the larger bridges would increase considerably faster than strengthening costs. Also, strengthning by posttensioning creates savings by avoiding costly detours when weight limits on bridges must be reduced.

• Record URL:
  • https://onlinepubs.trb.org/onlinepubs/trnews/rpo/rpo.trn127.pdf
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/07386826
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Publication Date: 1986-11

Media Info

• Pagination: p. 16-17
• Serial:
  • TR News
  • Issue Number: 127
  • Publisher: Transportation Research Board
  • ISSN: 0738-6826
  • Serial URL: https://doi.org/10.17226/895

Subject/Index Terms

• TRT Terms: Composite structures; Detours; Highway bridges; Live loads; Posttensioning; Regulation; Research; Savings; Size and weight regulations; Steel structures; Strength of materials; Stringers; Structural strengthening; Vehicle weight
• Old TRIS Terms: Simple span
• Subject Areas: Bridges and other structures; Construction; Design; Highways; Law; Maintenance and Preservation; Research; I24: Design of Bridges and Retaining Walls;

Filing Info

• Accession Number: 00462255
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Feb 28 1988 12:00AM