FIELD AND ALBORATORY STUDIES ON THE REACTIVITY OF SAND- GRAVEL AGGREGATES

FIELD AND LABORATORY STUDIES HAVE SHOWN THAT THOSE SAND- GRAVEL AGGREGATES THAT ARE ASSOCIATED WITH THE DETERIORATION OF CONCRETE IN THE KANSAS-NEBRASKA REGION ARE ALKALI-SILICA REACTIVE, WHILE SAND-GRAVELS WITH GOOD SERVICE RECORDS ARE NOT. HOWEVER, THE TYPE OF CONCRETE DISTRESS THAT IS OBSERVED IN THE FIELD IS NOT ALWAYS TYPICAL OF THE DISTRESS GENERALLY ASSOCIATED WITH ALKALI-SILICA REACTIVITY. SUCH ATYPICAL PERFORMANCE IS BELIEVED ATTRIBUTABLE TO THE SEVERE DRYING CONDITIONS IN THAT PART OF THE COUNTRY, WHICH, THROUGH THE CONCENTRATION AND REDISTRIBUTION OF THE ALKALIES IN THE CONCRETE, MAY BRING ABOUT REACTION WITH CEMENTS OF LOW ALKALI CONTENT. THE CONCRETE DETERIORATION IS BELIEVED DUE TO THE COMBINED EFFECTS OF MODERATE INTERIOR EXPANSION, CAUSED BY ALKALI-SILICA REACTIVITY, AND SURFACE SHRINKAGE, CAUSED BY UNUSUALLY SEVERE DRYING CONDITIONS. /PCA/

• Authors:
  • Hadley, D W
• Publication Date: 0

Media Info

• Serial:
  • Portland Cement Assoc R & D Lab Bull
  • Issue Number: 0

Subject/Index Terms

• TRT Terms: Alkali aggregate reactions; Concrete; Deterioration; Drying; Field studies; Laboratory studies; Sandy gravels; Shrinkage
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00213654
• Record Type: Publication
• Source Agency: Portland Cement Association
• Report/Paper Numbers: No 221
• Files: TRIS
• Created Date: Jun 1 1970 12:00AM