EFFECTS OF DOLOMITIC AND CALCITIC LIMES ON STRENGTH DEVELOPMENT IN MIXTURES WITH TWO CLAY MINERALS

CONFLICTING REPORTS ABOUT THE RELATIVE EFFECTIVENESS OF TWO PRINCIPAL LIME TYPES, DOLOMITIC MONOHYDRATED AND CALCITIC HYDRATED, IN SOIL STABILIZATION HAVE RESULTED IN A NEED TO RE-EVALUATE THE RESPONSE TO LIME STABILIZATION OF THE REACTIVE COMPONENTS IN SOILS. SAMPLES OF TWO CLAY MINEALS OCCURRING WIDELY IN SOILS, KAOLINITE AND MONTMORILLONITE, WERE SIZE-FRACTIONATED, CALCIUM-SATURATED, AND LIME-TREATED UNDER A VARIETY OF EXPERIMENTAL CONDITIONS. THE RESPONSE TO THE LIME TREATMENT WAS GAUGED BY CHANGES IN THE COMPRESSIVE STRENGTH OF COMPACTED SPECIMENS. MINERALOGICAL CHANGES IN CLAY-LIME MIXTURES WERE FOLLOWED BY MEANS OF X-RAY DIFFRACTION ANALYSIS. RESULTS SHOWED THAT THE CALCITIC LIME WAS MUCH MORE EFFECTIVE THAN THE DOLOMITIC LIME FOR IMPROVING THE STRENGTH CHARACTERISTICS OF KAOLINITE. WITH MONTMORILLONITE, HOWEVER, THE DOLOMITIC LIME WAS SLIGHTLY SUPERIOR WHEN SPECIMENS WERE CURED AT ROOM TEMPERATURE, BUT THE TWO LIMES PRODUCED ESSENTIALLY IDENTICAL RESULTS AT SLIGHTLY ELEVATEED TEMPERATURES. X-RAY DIFFRACTION RESULTS INDICATED THAT DIFFERENT TYPES OF CHEMICAL REACTIONS OCCURRED WITH THE TWO CLAY MINERALS. THE BONDING PHASE IN MIXTURES CONTAINING MONTMORILLONITE AND EITHER OF THE TWO LIME TYPES WAS A CALCIUM SILICATE HYDRATE, CSH (GEL); THE BONDING PHASE IN THE KAOLINITE-LIME-WATER MIXTURES WAS AN X-RAY AMORPHOUS PHASE OF INDETERMINATE COMPOSITION. /FHWA/

  • Corporate Authors:

    Federal Highway Administration

    Office of Research and Development, 1200 New Jersey Avenue, SE
    Washington, DC  USA  20590
  • Authors:
    • Ormsby, W C
    • Kinter, E B
  • Publication Date: 1972-8

Media Info

  • Pagination: 29 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00237237
  • Record Type: Publication
  • Source Agency: Federal Highway Administration
  • Report/Paper Numbers: FHWA-RD-72- 28 Intrm Rpt., FCP 24D3-021
  • Files: TRIS, USDOT
  • Created Date: Jul 16 1976 12:00AM