EFFECT OF PRESTRESS ON THE FATIGUE LIFE OF CONCRETE. INTERIM REPORT

This report presents results of a series of regression analyses carried out on data from both the Portland Cement Association and The University of Texas at Austin's test program on fatigue of prestressed concrete beams. Among the topics investigated were (1) the effect of prestress on the fatigue life of concrete, (2) the interaction of the static stresses due to prestressing and the dynamic stresses due to vehicular loadings, (3) the effect of prestress in delaying micro-crack propagation in concrete, and (4) the effect of prestress on the elasto-plastic behavior of prestressed concrete. As a result of this investigation, some salient facts about current fatigue design considerations for prestressed concrete pavement seem to emerge. (1) Present fatigue design is too conservative because it does not consider the beneficial effect of prestressing in helping to delay crack propagation. (2) For prestress levels of 300 psi or less, the current fatigue design is conservative because the fatigue life of the prestressed specimens was higher than the fatigue life of plain concrete. However, there is a strong indication that this may not be true with prestress levels higher than 300 psi. (3) The current design method of using superposition of stresses may not be valid because the fatigue life is dependent on the interaction between the static and dynamic stresses due to the prestressing and vehicular loading, respectively. (4) Prestressing helps in maintaining elasto-plastic behavior, which is ignored in current fatigue design.

• Supplemental Notes:
  • Research study title: Prestressed Concrete Pavement Design--Design and Construction of Overlay Applications.
• Corporate Authors:

  University of Texas, Austin

  Center for Transportation Research, 3208 Red River Street
  Austin, TX  United States  78705

  Texas State Department of Highways & Public Transportation

  Transportation Planning Division, P.O. Box 5051
  Austin, TX  United States  78763

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Chia, W S
  • Burns, N H
  • McCullough, B F
• Publication Date: 1986-11

Media Info

• Features: Appendices; Figures; References; Tables;
• Pagination: 130 p.

Subject/Index Terms

• TRT Terms: Beams; Concrete; Concrete pavements; Dynamic loads; Elastoplasticity; Fatigue (Mechanics); Microcracking; Pavement design; Prestressed concrete; Prestressing; Regression analysis; Static loads
• Uncontrolled Terms: Elastic plastic analysis; Fatigue life; Interaction
• Old TRIS Terms: Static loading
• Subject Areas: Data and Information Technology; Design; Highways; Materials; Pavements; I22: Design of Pavements, Railways and Guideways; I32: Concrete;

Filing Info

• Accession Number: 00464659
• Record Type: Publication
• Report/Paper Numbers: FHWA/TX-87+401-7, Res Rept 401-7, CTR 3-8-84-401-7
• Contract Numbers: Res Study 3-8-84-401
• Files: TRIS, USDOT, STATEDOT
• Created Date: Dec 31 1987 12:00AM