A Closer Look at Entrained Air in Concrete

Although an appropriate air-void system is needed when concrete will be exposed to a combination of moisture and cyclic freezing, current air content specifications evolved from data for concrete containing admixtures which are rarely used today. Significantly higher specific surfaces and lower void spacing factors at the same air content could be achieved using current air-entraining chemicals. These new chemicals produce smaller and more numerous bubbles at a given air content, thus producing significantly higher specific surfaces and significantly lower void spacing factors. This article suggests a reduction in specified air contents is warranted to avoid the deleterious effects of excessive entrained air. The benefits of reducing minimum air contents would include higher strength, fewer finishing problems and reduced vulnerability to higher-than-specified air contents as a result of job site addition of high-range water reducers or retempering water.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/4163061
• Authors:
  • Jana, Dipayan
  • Erlin, Bernard
  • Pistilli, Michael F
• Publication Date: 2005-7

Language

• English

Media Info

• Media Type: Print
• Features: Figures; References; Tables;
• Pagination: pp 31-34
• Serial:
  • Concrete International
  • Volume: 27
  • Issue Number: 7
  • Publisher: American Concrete Institute (ACI)
  • ISSN: 0162-4075

Subject/Index Terms

• TRT Terms: Admixtures; Air content; Air entrained concrete; Air entraining agents; Air voids; Bubbles; Entrained air; Freeze thaw durability; Specifications
• Subject Areas: Highways; Materials; I32: Concrete;

Filing Info

• Accession Number: 01002382
• Record Type: Publication
• Files: TRIS
• Created Date: Jul 28 2005 7:49AM