Chemical Modification of Uniform Soils and Soils with High/Low Plasticity Index

The addition of chemicals into the subgrade has been widely used during construction to improve the soil properties. The chemicals, often Lime Kiln Dust (LKD) and Portland cement, are added to the soil to improve its workability, compactability and engineering properties. Many departments of transportation (DOTs) have been using chemical modification for more than 20 years. In fact, 90% of the current subgrade is treated. Despite the wide experience-based in treating subgrade soils, several problems still exist. The Indiana Department of Transportation (INDOT) design manual states that subgrade clays with low plasticity (PI< 10) must be treated with cement and that high plasticity clays (Density < 95 pcf, or PI ≥ 25) in the subgrade must be replaced with suitable soils. Uniform granular soils do not stabilize with lime products or with low dosage of cement. Current knowledge does not provide information about stabilization of these soils. This research explores LKD, combinations of LKD and Portland cement to treat high and low plasticity clayey soils (problem soils, e.g. expansive and organic soils are not considered in the research) and treatment with Portland cement of uniform granular soils. A comprehensive laboratory testing program has been undertaken to investigate the potential for the treatment and to report the changes in mineralogy and engineering properties of the treated soils with time. Unconfined compression tests performed over time, as well as XRD tests, show that treatment is possible and that it remains over time since the strength of the treated soil improves with time and its mineralogy does not change.

• Record URL:
  https://doi.org/10.5703/1288284316359
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/9781622604517
• Corporate Authors:

  Purdue University

  Joint Transportation Research Program
  West Lafayette, IN  United States  47907-2051

  Indiana Department of Transportation

  State Office Building
  100 North Senate Avenue
  Indianapolis, IN  United States  46204

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Tao, Fei
  • Li, Xuanchi
  • Bobet, Antonio
  • Siddiki, Nayyar Zia
• Publication Date: 2016-8

Language

• English

Media Info

• Media Type: Digital/other
• Edition: Final Report
• Features: Appendices; Figures; Photos; References; Tables;
• Pagination: 32p

Subject/Index Terms

• TRT Terms: Calcium oxide; Clay soils; Geotechnical engineering; Granular soils; Kiln dust; Plasticity index; Portland cement; Soils; Subgrade (Pavements)
• Uncontrolled Terms: Soil modification
• Subject Areas: Geotechnology; Highways; Pavements;

Filing Info

• Accession Number: 01634602
• Record Type: Publication
• ISBN: 9781622604517
• Report/Paper Numbers: FHWA/IN/JTRP‐2016/32
• Contract Numbers: SPR‐3940
• Files: TRIS, ATRI, USDOT, STATEDOT
• Created Date: Mar 31 2017 11:24AM