A STUDY OF CONCRETE CONSOLIDATION

IN SOME INSTANCES AN UNDESIRABLY HIGH NUMBER OF AIR AND WATER POCKEST ARE FOUND IN THE CORES TAKEN FROM THE CONCRETE PAVEMENTS IN ALABAMA. THE PRESENCE OF THESE POCKETS HAS BEEN ATTRIBUTED TO INADEQUATE COMPACTION OF THE FRESH CONCRETE. THE EFFECT THAT SEVERAL OF THE VARIABLES WHICH INFLUENCE COMPACTABILITY HAVE ON THE QUANTITY OF ENTRAPPED AIR IN THE VIBRATED CONCRETE WAS STUDIED. FOR STIFF MIXES, THE RESULTS DEMONSTRATED THAT: THE PERCENTAGE OF ENTRAPPED AIR IS NOT SIGNIFICANTLY REDUCED AS THE VIBRATION TIME IS INCREASED BEYOND 5 SECONDS; THE PERCENTAGE OF ENTRAPPED AIR CAN BE GREATLY INFLUENCED BY THE CHARACTERISTICS OF THE COARSE AGGREGATE IN THE MIX; AN INCREASE IN THE VIBRATOR AMPLITUDE OR FREQUENCY DOES NOT SIGNIFICANTLY REDUCE THE PERCENTAGE OF ENTRAPPED AIR; THE PERCENTAGE OF ENTRAPPED AIR DECREASES AS THE THICKNESS OF CONCRETE INCREASES FROM 6 TO 18 INCHES; AND THE COMPRESSIVE STRENGTH OF CONCRETE SPECIMENS WITH LARGE VOLUMES OF ENTRAPPED AIR WERE IN GENERAL GREATER THAN 3,000 PSI. /AUTHOR/

Media Info

  • Pagination: 51 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00213905
  • Record Type: Publication
  • Report/Paper Numbers: HPR 50
  • Files: TRIS, USDOT, STATEDOT
  • Created Date: Jun 22 1971 12:00AM