Super Air Meter for Assessing Air-Void System of Fresh Concrete

A key factor for freeze-thaw durability of concrete is the air void system, nevertheless, the current test methods for fresh concrete only allow for determination of total air content. There is a need for a fresh concrete test method capable of indicating that air void size and distribution are adequate. In an attempt to address this need, a new test method based on the Super Air Meter (SAM) was developed by Ley and Tabb. This paper presents an investigation of the air void system of 64 mixtures employing standard fresh and hardened concrete test methods, as well as the SAM test method. The study focused on mixtures with three different coarse aggregates, three air entraining admixtures, different total air contents levels and slumps below 3 in., typical of paving concrete. Freeze-thaw tests were carried out on some of the mixtures with marginal air content. Data from this study at the Federal Highway Administration’s Turner Fairbank Highway Research Center Laboratory showed that the SAM test of fresh concrete was able to provide an indication of air void adequacy in low-slump air entrained concrete; a SAM number of 0.20 psi or above identified mixtures with poor spacing factor. However, a limit of 4.0% fresh air content was also able to identify these mixtures as a good correlation between air content and spacing factor was found. Work by others with different materials has shown that this trend is not always appropriate.

• Supplemental Notes:
  • This paper was sponsored by TRB committee AFN20 Properties of Concrete.
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Tanesi, Jussara
  • Kim, Haejin
  • Beyene, Mengesha
  • Ardani, Ahmad A
• Conference:
  • Transportation Research Board 94th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2015-1-11 to 2015-1-15
• Date: 2015

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; Photos; References; Tables;
• Pagination: 16p
• Monograph Title: TRB 94th Annual Meeting Compendium of Papers

Subject/Index Terms

• TRT Terms: Air entrained concrete; Air voids; Freeze thaw durability; Fresh concrete; Pressure gages; Prototypes; Test procedures
• Subject Areas: Highways; Materials; Pavements; I32: Concrete;

Filing Info

• Accession Number: 01553740
• Record Type: Publication
• Report/Paper Numbers: 15-2888
• Files: TRIS, TRB, ATRI
• Created Date: Feb 21 2015 4:38PM