SAFETY OF PRESTRESSED CONCRETE BRIDGES TO FATIGUE: APPLICATION TO SERVICEABILITY LIMIT STATE OF DECOMPOSITION

A method for the fatigue reliability assessment of posttensioned concrete bridges is applied to a wide spectrum of highway bridges covering over the most commonly built with this technique. The objective is to obtain the fatigue performance of reinforcing bars and prestressing strands. First bridge geometry and properties are defined, and different degrees of prestressing are considered. The reliability indices are worked out for ultimate limit state of fatigue and bending and for heavy and light traffic conditions. In this way, a method to identify the minimum prestressing required by a given probability of fatigue-induced failure for a 100-year service life is derived. Fatigue in the steel elements and cracking are closely related, mainly in the posttensioning tendons, where the fretting fatigue effects are of concern. Thus, based on the results of the fatigue analysis, the paper identifies an objective criteria to check the serviceability limit state of decompression. In comparison, current criteria in bridge codes seem to be overconservative. Conclusions regarding the main factors affecting bridge performances under fatigue are also drawn.

• Record URL:
  http://www.concrete.org/Publications/InternationalConcreteAbstractsPortal.aspx.aspx?m=details&i=835
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/13846957
• Supplemental Notes:
  • Financial support was provided by the Spanish Ministry of Higher Education (Direccion General de Ensenanza Superior), Research Grants PB94-1199, PB95-0769, and TAP99-1079.
• Corporate Authors:

  American Concrete Institute (ACI)

  38800 Country Club Drive
  Farmington Hills, MI  United States  48331
• Authors:
  • CASAS, J R
• Publication Date: 2000-1

Language

• English

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 68-74
• Serial:
  • ACI Structural Journal
  • Volume: 97
  • Issue Number: 1
  • Publisher: American Concrete Institute (ACI)
  • ISSN: 0889-3241
  • Serial URL: http://www.concrete.org/PUBS/JOURNALS/SJHOME.ASP

Subject/Index Terms

• TRT Terms: Bending; Building codes; Cracking; Decompression; Fatigue (Mechanics); Geometry; Highway bridges; Live loads; Posttensioning; Prestressed concrete bridges; Prestressing; Reinforcing bars; Reinforcing steel; Reliability; Safety; Service life; Serviceability; Tendons (Materials); Traffic volume
• Subject Areas: Bridges and other structures; Design; Highways; Law; Safety and Human Factors; I24: Design of Bridges and Retaining Walls;

Filing Info

• Accession Number: 00789052
• Record Type: Publication
• Contract Numbers: CMS-9640570
• Files: TRIS
• Created Date: Mar 29 2000 12:00AM