EVALUATION OF REMOLDED FIELD SAMPLES OF LIME-CEMENT-FLY ASH-AGGREGATE MIXTURES

IN LATE SEASON CONSTRUCTION USING LIME-CEMENT-FLY ASH-AGGREGATE (LCFAA) MIXTURES, THE REACTION PROCESS MAY BE GREATLY RETARDED BY COOL TEMPERATURES. CONSTRUCTION OF THE RUNWAYS AND TAXIWAYS AT THE NEWARK AIRPORT PROVIDED AN EXCELLENT OPPORTUNITY TO COLLECT THE NECESSARY MATERIALS FOR A STUDY TO DETERMINE IF LIME AND CEMENT DOES MIGRATE OR IS LEACHED FROM THE MATERIALS DURING ADVERSE CLIMATIC CONDITIONS. A LABORATORY INVESTIGATION WAS DESIGNED TO DETERMINE THE EXTENT OF LEACHING OR MIGRATION OF THE LIME AND CEMENT UNDER THE FIELD CONDITIONS DESCRIBED AND THE EFFECT OF THE LEACHING AND CURING CONDITIONS ON THE SUBSEQUENT CURING OF THE LCFAA MATERIALS. THE TEST PROGRAM CONSISTED OF: (1) TITRATION AND PH TESTS ON ALL FIELD SAMPLES, (2) STRENGTH AND DURABILITY TESTS ON SELECTED SAMPLES OF REMOLDED MATERIAL, AND (3) A LABORATORY STUDY TO EVALUATE LEACHING UNDER CONTROLLED CONDITIONS. FINDINGS INDICATE THAT THE LIME AND CEMENT IN THE LCFAA MIXTURES USED IN THE NEWARK AIRPORT PAVEMENTS ARE STABLE AND ARE NOT SUBJECT TO SIGNIFICANT LEACHING OR MIGRATION OVER SHORT PERIODS OF TIME SPECIFICALLY, THE FINDINGS INDICATE THAT THOSE LCFAA MATERIALS PLACED LATE IN THE CONSTRUCTION SEASON WILL RETAIN NEARLY ALL OF THE LIME AND CEMENT THAT WERE ADDED DURING MIXING AND THAT THIS LIME AND CEMENT WILL REACT WITH OTHER COMPONENTS OF THE MIXTURE UNDER FAVORABLE CONDITIONS EVEN AFTER BEING DORMANT FOR A CONSIDERABLE PERIOD. FINDINGS INDICATE THAT THE MORE EXTENSIVE CURING IS BEFORE FREEZING AND THAWING, THE LESS DAMAGE WILL BE DONE TO THE MATERIALS BY CYCLIC FREEZING AND THAWING. MATERIALS DAMAGED BY FREEZING AND THAWING WILL RECOVER A SIGNIFICANT PORTION OF THE LOST STRENGTH UNDER FAVORABLE CURING CONDITIONS PROVIDED SUFFICIENT LIME AND CEMENT ARE RETAINED IN THE MIXTURE TO SUPPORT CONTINUING REACTIONS. IT WAS OBSERVED THAT WHEN THE LCFAA MATERIALS ARE SUBJECTED TO ALTERNATE FREEZE-THAW CYCLES UNDER THE CONDITIONS USED IN THIS STUDY, THE MOST SEVERE DAMAGE TO THE MATERIALS OCCURS NEAR THE TOP OF THE SPECIMENS FOR A DEPTH OF FROM 1 TO 2 INCHES.

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 112-121
  • Monograph Title: Soil stabilization: multiple aspects
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00232963
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Nov 9 1970 12:00AM