DEEP LIME INJECTION STABILIZES MAIL SITE

Lime slurry pressure-injection to 12-ft depth under building sites totaling about 900,000 sq ft was decided upon for stabilizing the foundation of the proposed Windsor Park Mall in San Antonio, Texas. Swell control alone was the purpose for stabilizing the soils beneath the mall buildings. However, increase in soil strengths throughout the depth was anticipated. The lime slurry was injected into the ground at a pump pressure of about 50 to 200 psi, regulated to allow the greatest volume of slurry into the soil. A surfactant in the slurry was used to decrease the surface tension of the water, producing an apparent increase in soil permeability. Where the clay was soft enough in the Windsor Park project, steel tubes were hydraulically forced in for the injection. But for over 33,000 holes in the hard clays, rock percussion drills or a truck-mounted rotary drill were brought in to expedite the work. The slurry used was a mixture of 2.5 to 3 lb of hydrated lime per gal of water and produced a specific gravity of about 1.14 to 1.16. Specifications called for injecting 10 gal per ft of hole, or 120 gal per hole - a target not always achieved due to the soil's tight structure. A maximum heave of 3 inches was obtained. The subgrade was stabilized in a similar manner and is proving satisfactory.

  • Corporate Authors:

    Dun Donnelley Publishing Corporation

    222 South Riverside Plaza
    Chicago, IL  USA  60606
  • Publication Date: 1975-8

Media Info

  • Features: Photos;
  • Pagination: p. 46-48
  • Serial:
    • Roads and Streets
    • Volume: 118
    • Issue Number: 8
    • Publisher: Donnelley (Reuben H) Corporation

Subject/Index Terms

Filing Info

  • Accession Number: 00125442
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Nov 5 1975 12:00AM