BEHAVIOUR OF PRESTRESSED CONCRETE BOX GIRDERS MADE OF PRECAST SEGMENTS AND SUBJECTED TO COMBINED BENDING, TORSION AND SHEAR

Prestressed concrete box beams, similar to those used in cantilever and other bridge constructions made of precast concrete segments were tested under combined bending, torsion and shear. The cross-section and the span of the beam were kept constant while the length of the segments, magnitude of the prestressing force and its eccentricity, the ratio of torque to the moment were considered as variable parameters. The deflection, the opening of the joints between the segments and the ultimate strength of the beam were studied. Diagonal cracks have formed in the critical segments, and for small ratios of torque to moment, the diagonal cracks got terminated at the construction joints. The cracks propagated across the joints for torque-moment ratios greater than 0.10. All the specimens with the torque-moment ratios less than 0.24 failed in primary flexure. The length of the segment and the web reinforcement did not influence the ultimate capacity of the beam. However the load at cracking decreased with the decrease in the length of the segment. /TRRL/

• Supplemental Notes:
  • Proceeding of the Symposium on Prestressed Concrete.
• Corporate Authors:

  CONCRETE INSTITUTE OF AUSTRALIA

  PO BOX 848
  SYDNEY, NEW SOUTH WALES  Australia  1585
• Authors:
  • Dayaratnam, P
  • Populi, JYT
• Publication Date: 1976

Language

• English

Media Info

• Features: Figures; References; Tables;
• Pagination: 14 p.

Subject/Index Terms

• TRT Terms: Beams; Bending; Box girders; Cantilevers; Conferences; Deflection; Flexure; Fracture mechanics; Loads; Precast concrete; Prestressed concrete; Shear strength; Torsion; Ultimate strength; Webbing
• ITRD Terms: 3472: Beam; 3474: Box girder; 8525: Conference; 5586: Deflection; 5567: Load; 4792: Precast concrete; 4796: Prestressed concrete; 5531: Shear; 5512: Torsion
• Subject Areas: Bridges and other structures; Construction; Design; Highways; I24: Design of Bridges and Retaining Walls;

Filing Info

• Accession Number: 00164164
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• Report/Paper Numbers: Proceeding
• Files: ITRD, TRIS
• Created Date: Jun 28 1978 12:00AM