TORSIONAL-BALANCED STEEL IN CONCRETE BEAMS

Presently design of rectangular concrete beams under torsion is limited to underreinforced sections only. To ascertain the underreinforced character of a concrete beam it is necessary to know the balance or maximum percentage of longitudinal and stirrup steel which can yield at failure of the beam. A semitheoretical approach based on space truss analogy has been presented to evaluate the torsional balanced percentages of reinforcements. For equal yield stresses, the balanced volume ratio between longitudinal and stirrup steel equals 1.3. Total percentage of torsional-balanced steel depends upon the concrete strength, yield stresses of reinforcements, the ratios of larger to shorter dimension of stirrups and core area to toal cross-sectional area of the beam. Beams failing under torsion can be classified according to yielding of both, either or none of the form of longitudinal and stirrup steel. Unlife flexure, a torsional-balanced failure is not accompanied by crushing of concrete. /Author/

• Corporate Authors:

  American Society of Civil Engineers

  345 East 47th Street
  New York, NY  United States  10017-2398
• Authors:
  • Chakraborty, M
• Publication Date: 1977-11

Media Info

• Features: Appendices; Figures; References; Tables;
• Pagination: p. 2181-91
• Serial:
  • Journal of the Structural Division
  • Volume: 103
  • Issue Number: ST11
  • Publisher: American Society of Civil Engineers

Subject/Index Terms

• TRT Terms: Beams; Concrete; Failure; Reinforced concrete; Steel; Stirrups; Strength of materials; Stresses; Torsion; Trusses
• Uncontrolled Terms: Concrete beams
• Subject Areas: Bridges and other structures; Highways;

Filing Info

• Accession Number: 00168431
• Record Type: Publication
• Report/Paper Numbers: ASCE 13359 Proceeding
• Files: TRIS
• Created Date: Feb 16 1978 12:00AM