DESIGN OF REINFORCEMENT FOR NOTCHED ENDS OF PRESTRESSED CONCRETE GIRDERS

This study was intended to analyze the shear strength of the notched ends of prestressed concrete girders and to evaluate the ultimate shear capacity by testing a model with reinforcing details simpler than those currently adopted in practice. Various discrete element analyses by a computer program showed that it is possible to identify the most highly stressed regions of an end block and also to predict a likely crack pattern that would occur before failure. One specimen with two different end block details was tested to failure. The failure of the specimen did not occur at either notch, and the notch capacity with uncongested reinforcement was shown to be adequate for the intended load. The end block with the provision of a hanger strap assembly and reinforcement welded to the bearing plate behaved well during the test. As concluded from the observation of crack widths, such a design with hanger straps seems to possess a higher degree of serviceability than a design based on the provision of large web plates embedded at the notched end. A design procedure derived from two potential failure modes has been suggested. The two failure modes involved are (a) a shear friction separation parallel to the inclined hanger strap reinforcement and (b) a shear compression separation from the corner of the notch into the flexural compression zone of the end block. An example design for the end block of a standard highway bridge stringer has been given to illustrate the design procedure. (FHWA)

• 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 Transp

  P.O. Box 5051
  Austin, TX  United States  78763

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Menon, Gopinath
  • Furlong, R W
• Publication Date: 1977-8

Media Info

• Pagination: 166 p.

Subject/Index Terms

• TRT Terms: Computer aided design; Fracture mechanics; Girders; Material reinforcement; Prestressed concrete; Shear strength; Stresses
• Old TRIS Terms: Ends; Notch
• Subject Areas: Bridges and other structures; Design; Highways; I24: Design of Bridges and Retaining Walls;

Filing Info

• Accession Number: 00373069
• Record Type: Publication
• Report/Paper Numbers: FHWA/TX-78/07+196-1FFinal Rpt.
• Contract Numbers: 3-5-76-196
• Files: TRIS, USDOT, STATEDOT
• Created Date: Jun 30 1983 12:00AM