CONCRETE WEATHERING STUDIES

THE CARBONATE AGGREGATE PROBLEM IN IOWA IS REVIEWED. A CONCRETE AGING STUDY WAS UNDERTAKEN TO REVIEW IN A SYSTEMATIC WAY THE PHYSICAL AND CHEMICAL CHANGES WHICH OCCUR WITH TIME IN HIGHWAY CONCRETES. DURING PETROGRAPHIC INVESTIGATIONS, IT WAS OBSERVED THAT CHANGES IN THE BREAKING BEHAVIOR BONDS ZONE OF THE COARSE AGGREGATE AND THE MATRIX DEPENDED ON TIME AND LITHOLOGY OF THE AGGREGATE. THE AGING STUDY INDICATES THAT AIR ENTRAINED AND NON-AIR ENTRAINED CONCRETES UNDERGO SIMILAR CHEMICAL CHANGES BUT AT DIFFERENT RATES. MATRIX CHANGES APPEAR TO OCCUR AT FASTER RATES IN AIR ENTRAINED CONCRETES. CONCRETE STRENGTH APPEARS TO BE DEPENDENT ON LITHOLOGIES ONLY AFTER ENOUGH TIME HAS ELAPSED TO ALLOW ALKALI-REACTION TO EFFECT BOND STRENGTH CHARACTERISTICS. IT IS INDICATED THAT ALKALI REACTIONS CAN EFFECT THE BOND ZONE PERFORMANCE OF AGGREGATES.

• Supplemental Notes:
  • pp 184-191, 3 FIG, 7 REF
• Authors:
  • Lemish, J
• Conference:
  • Highway Geology Symposium, Iowa State U
• Publication Date: 1968-7

Subject/Index Terms

• TRT Terms: Air entrained concrete; Alkali aggregate reactions; Bonds; Carbonates; Coarse aggregates; Concrete aggregates; Geological surveying; Petrography; Weathering
• Old TRIS Terms: Aging; Petrographic investigations
• Subject Areas: Geotechnology; Highways; Materials;

Filing Info

• Accession Number: 00213351
• Record Type: Publication
• Report/Paper Numbers: pp 128-129
• Files: TRIS
• Created Date: Jul 7 1994 12:00AM