COEFFICIENT OF LINEAR THERMAL EXPANSION OF EPOXY RESIN MORTARS

EPOXY RESIN MATERIALS HAVE BEEN USED SINCE 1959 FOR THE RAPID REPAIR OF AIRFIELD PAVEMENTS; SOME HAVE BEEN HIGHLY SUCCESSFUL, OTHERS HAVE FAILED. SOME OF THE FAILURES MAY BE ATTRIBUTED TO INTERNAL STRESS IN THE EPOXY RESIN MATERIAL. THESE STRESSES COULD BE DUE TO CURING SHRINKAGE OR TO THE DIFFERENCE IN COEFFICIENT OF LINEAR THERMAL EXPANSION BETWEEN THE EPOXY PATCH AND PORTLAND CEMENT CONCRETE. THIS STUDY WAS UNDERTAKEN TO OBTAIN INFORMATION ABOUT THE THERMAL EXPANSION AND CURING SHRINKAGE OF EPOXY RESIN MORTARS AND CONCRETES. IT REVEALED THAT THERE IS A SIGNIFICANT DIFFERENCE IN THE COEFFICIENTS OF LINEAR THERMAL EXPANSION OF THE VARIOUS EPOXY RESIN MORTAR SYSTEMS TESTED; THEY ARE 2--4 TIMES GREATER THAN THE ACCEPTED VALUE (5--7 X 0.000001 IN/IN/DEG F) FOR PORTLAND CEMENT CONCRETE. AS EXPECTED, THE COEFFICIENT DECREASES WITH AN INCREASE IN AGGREGATE CONTENT FOR DRY, UNSATURATED SPECIMENS. HOWEVER, IT APPEARS THAT THERE IS AN OPTIMUM AGGREGATE CONTENT FOR SATURATED SPECIMENS, AFTER WHICH THE COEFFICIENT INCREASES AS AGGREGATE CONTENT IS INCREASED. ABSORBED MOISTURE INCREASES THE COEFFICIENT OF THERMAL EXPANSION; THEREFORE EPOXY RESIN MORTARS AND CONCRETES SHOULD BE DESIGNED TO PREVENT ABSORPTION BY SELECTION OF THE PROPER AGGREGATE-TO-BINDER RATIO AND BY PLACEMENT TECHNIQUES THAT WILL PROVIDE A DENSE IMPERMEABLE PATCH. MAXIMUM SHRINKAGE IS GENERALLY ACHIEVED WITHIN TWO MONTHS WHEN CURING OCCURS AT 73 F AND A RELATIVE HUMIDITY OF 55%. PAVEMENT TEMPERATURES, DURING AND SHORTLY AFTER REPAIR IS MADE, MAY INFLUENCE THE AMOUNT OF STRESSES THAT DEVELOP IN THE RESIN CONCRETE DUE TO CURING. /AUTHOR/

  • Corporate Authors:

    Construction Engineering Research Laboratory

    Army Corps of Engineers, P.O. Box 4005
    Champaign, IL  USA  61820
  • Authors:
    • Kemphues, R F
  • Publication Date: 1972-4

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 1-9

Subject/Index Terms

Filing Info

  • Accession Number: 00217240
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Feb 3 1973 12:00AM