REVIEW OF EXPANSIVE ALKALI-AGGREGATE REACTIONS IN CONCRETE. TECHNICAL NOTE

Expansive alkali-aggregate reactions (AAR) occur frequently worldwide, causing durability failure in Portland cement concrete. Deleterious AAR generally result in expansion and map-cracking in plain concrete; however, in reinforced or prestressed concrete, cracks may display a linear relationship to reinforcement. Expansion can lead to buckling, extrusion of joint filler, and displacement of equipment set in concrete. Expansion can also cause white deposits of silica gel, rims surrounding aggregate particles, pop outs, loss of strength, and decrease in modulus of elasticity. Damage may be so extreme that concrete has to be replaced, but less drastic remedial measures have been tried when the damage is less severe. Using petrographic methods, length-change tests, and examination of similarly deteriorated concrete, aggregates likely to cause expansive AAR can be identified. Potential expansion due to AAR may be minimized by decreasing the available supply of alkalies in concrete, use of mineral and chemical admixtures, design to limit wetting, and the beneficiation of aggregates. The author reviews classification of the types of reaction and mechanisms of expansion.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/08991561
• Corporate Authors:

  American Society of Civil Engineers

  345 East 47th Street
  New York, NY  United States  10017-2398
• Authors:
  • Gillott, J E
• Publication Date: 1995-11

Language

• English

Media Info

• Features: Appendices; Figures; References;
• Pagination: p. 278-282
• Serial:
  • Journal of Materials in Civil Engineering
  • Volume: 7
  • Issue Number: 4
  • Publisher: American Society of Civil Engineers
  • ISSN: 0899-1561
  • EISSN: 1943-5533
  • Serial URL: http://ascelibrary.org/journal/jmcee7

Subject/Index Terms

• TRT Terms: Alkali aggregate reactions; Cracking; Durability; Expansion; Loss and damage; Portland cement concrete
• Uncontrolled Terms: Damage severity
• Subject Areas: Highways; Materials; I32: Concrete;

Filing Info

• Accession Number: 00713725
• Record Type: Publication
• Files: TRIS
• Created Date: Nov 5 1995 12:00AM