00488731

Component

http://onlinepubs.trb.org...trr/1988/1190/1190-003.pdf

https://scholar.google.co...mith&publication_year=1988

Strength increases resulting from carbonate cementation in compacted sands and cemented coquina highway base course materials of variable quartz-calcite composition were investigated through the use of limerock-bearing-ratio (LBR) testing. Quartz and calcite sands were mixed in various proportions, compacted into LBR molds, soaked for time periods from 2 days up to 60 days, and tested to determine strength increase with time. For comparison, cemented coquina highway base course materials of variable quartz-calcite composition were also compacted, soaked, and tested. In addition, duplicate sets of specimens were tested that had 1 percent Ca(OH)2 (hydrated lime) mixed with the dry materials before compacting and soaking. This was done to provide a source of Ca2+ ions for formation of additional carbonate cement. Results of the LBR testing program showed that more strength developed as the calcium carbonate composition of both the quartz-calcite sand mixes and the cemented coquina samples increased. Addition of Ca(OH)2 to the samples enhanced carbonate cementation effects, with large strength increases occurring in high-carbonate materials. Scanning electron microscopic examinations of the tested LBR materials, base course materials cored from in-service highways, and naturally occurring calcite-cemented quartz sandstones and limestones revealed different bonding characteristics between calcite cement-calcite particle and calcite cement-quartz particle systems, which would explain the strength development patterns observed in LBR testing.

This paper appears in Transportation Research Record No. 1190, Artificial Ground Freezing and Soil Stabilization. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved

01413988

p. 24-30

1988

Transportation Research Record

0309047587

Figures (13) ; References (15)

Base course (Pavements); Bearing capacity; Bonding; Calcites; Calcium hydroxide; Carbonates; Compacted soils; Electron microscopy; Laboratory tests; Limestone; Sand; Silica sands; Strength of materials

Scanning electron microscopy

Geotechnology; Highways; I42: Soil Mechanics

TRIS, TRB, ATRI

Oct 31 1989 12:00AM

• BEHAVIOR OF CEMENT-TREATED SOILS IN FLEXURE
• BEHAVIOR OF FROZEN AND UNFROZEN SANDS IN TRIAXIAL TESTING
• COMPARISON OF QUICKLIME AND HYDRATED LIME SLURRIES FOR STABILIZATION OF HIGHLY ACTIVE CLAY SOILS
• EFFECT OF LIME ON A HIGHLY PLASTIC CLAY WITH SPECIAL EMPHASIS ON AGING
• EFFECTS OF PULVERIZATION ON THE STRENGTH AND DURABILITY OF HIGHLY ACTIVE CLAY SOILS STABILIZED WITH LIME AND PORTLAND CEMENT
• FIELD EVALUATION OF CRITERIA FOR FROST SUSCEPTIBILITY OF SOILS
• MINIMUM REQUIREMENTS FOR TEMPORARY SUPPORT WITH ARTIFICIALLY FROZEN GROUND
• MODEL SIMULATIONS OF WINCHENDON FREEZE-THAW FIELD DATA