ELECTROCHEMICAL HARDENING OF CLAY SOILS

CLAY SOILS WERE STRENGTHENED BY INTRODUCING ALUMINUM INTO THE SOIL UNDER AN ELECTROCHEMICAL GRADIENT. CHANGES IN BOTH THE COMPOSITION AND PHYSICAL PROPERTIES OF THE TREATED SOILS WERE INVESTIGATED. THE ROLE OF PH AND PH BUFFERING DURING TREATMENT WAS ALSO EXAMINED. STRENGTH INCREASES OR DECREASES IN THE TREATED SAMPLES WERE SEPARATED INTO THREE COMPONENTS: THOSE CAUSED BY A CHANGE IN WATER CONTENT, ELECTRO-OSMOTIC EFFECTS; THOSE CAUSED BY AGE HARDENING, THIXOTROPIC EFFECTS; AND THOSE CAUSED BY ELECTROCHEMICAL ACTION, ION EXCHANGE AND MINERALIZATION. NEARLY ALL TREATED SAMPLES EXHIBITED SOME DEGREE OF ELECTROCHEMICAL HARDENING. INDURATION WAS MOST PRONOUNCED IN A HIGH WATER CONTENT, HIGH PH, BENTONITIC SOIL DUE LARGELY TO HYDROXY-ALUMINIUM INTERLAYING IN THE CLAY. IN A LOW PH, ILLITIC SOIL INTERLAYERING WAS NEGLIGIBLE AND HARDENING APPEARS TO HAVE RESULTED PRIMARILY FROM ION EXCHANGE. BOTH X-RAY DIFFRACTION AND SELECTIVE EXTRACTION METHODS WERE USED TO DETERMINE THE DISTRIBUTION AND MODE OF OCCURRENCE OF ALUMINUM IN THE TREATED SAMPLES. MINERALIZATION BY ALUMINUM IN BENTONITIC SOILS WAS SPEEDED AND INTENSIFIED BY BUFFERING THE CATHOLYTE WITH CARBON DIOXIDE. INDURATION TENDED TO OCCUR SLOWLY AS EVIDENCED BY A TIME DEPENDENT STRENGTH INCREASE, EXCLUSIVE OF REVERSIBLE, THIXOTROPIC EFFECTS, IN MOST SAMPLES AFTER TREATMENT. /RRL(A)/

  • Availability:
  • Supplemental Notes:
    • Vol 20, No 1, PP 81-93, 15 FIG, 1 TAB, 1 PHOT, 16 REF
  • Corporate Authors:

    Road Research Laboratory /UK

    ,    
  • Authors:
    • GRAY, D H
  • Publication Date: 0

Media Info

  • Serial:
    • GEOTECHNIQUE
    • Volume: 4
    • Issue Number: 3
    • Publisher: Thomas Telford Limited
    • ISSN: 0016-8505

Subject/Index Terms

Filing Info

  • Accession Number: 00232218
  • Record Type: Publication
  • Source Agency: Road Research Laboratory /UK
  • Files: TRIS
  • Created Date: Oct 10 1971 12:00AM