DURABILITY OF LIGHTWEIGHT CONCRETE, PHASE 3, FREEZING AND THAWING TESTS OF LIGHTWEIGHT CONCRETE

THIS REPORT IS PRIMARILY CONCERNED WITH DEVELOPMENT OF A CRITERION TO BE USED IN STRUCTURAL CONCRETE. IT COVERS PHASE III, FREEZING AND THAWING RESISTANCE, OF A THREE-PHASE PROJECT DEALING WITH DURABILITY OF LIGHTWEIGHT CONCRETE. THE TESTING PROGRAM COVERED THREE SOURCES OF LIGHTWEIGHT AGGREGATE AND ONE SOURCE OF SAND AND GRAVEL. THE TESTS CONSISTED OF SUBJECTING CONCRETE SPECIMENS CONTAINING VARIOUS CEMENT CONTENTS, AGGREGATE GRADATIONS AND MOISTURE CONDITIONS OF AGGREGATES OF RAPID FREEZING AND THAWING. IN ADDITION, COMPLETE PHYSICAL TESTS WERE MADE ON THE AGGREGATES. THE RESULTS OBTAINED ON THOSE TESTS WARRANT THE FOLLOWING CONCLUSIONS' 1/ LIGHTWEIGHT CONCRETE HAS GREATER RESISTANCE TO FREEZING AND THAWING THAN NORMAL CONCRETE USED IN THIS AREA, 2/ LIGHTWEIGHT FINE AGGREGATE SHOULD NOT HAVE MORE THAN 20 PERCENT PASSING NO. 100 SIEVE, 3/ MOISTURE CONDITION OF THE AGGREGATE HAS LITTLE EFFECT ON THE RESISTANCE TO FREEZING AND THAWING, 4/ REDUCTION IN DURABILITY WHEN CEMENT CONTENT WAS INCREASED FROM 5.5 TO 6.0 SACKS PER CU. YD. CANNOT BE EXPLAINED, 5/ USE OF CONCRETE SAND TO REPLACE LIGHTWEIGHT FINES HAD NO SIGNIFICANT EFFECT ON DURABILITY, 6/ DRYING SHRINKAGE OF LIGHTWEIGHT CONCRETE IS DIFFERENT FOR EACH SOURCE. CONCRETE SAND USED TO REPLACE LIGHTWEIGHT FINES REDUCED SHRINKAGE, AND 7/ THE TEST CRITERION FOR DURABILITY OF LIGHTWEIGHT CONCRETE SHOULD BE 500 CYCLES OF FREEZING AND THAWING. /BPR/

Subject/Index Terms

Filing Info

  • Accession Number: 00211988
  • Record Type: Publication
  • Files: TRIS, STATEDOT
  • Created Date: Mar 1 1994 12:00AM