LIME-FLY ASH-STABILIZED BASES AND SUBBASES

The mixture and mixture properties of lime-fly ash-mixtures (LFA) are described as well as pavement behavior and performance, selection of mixture proportions, construction procedures, applications and limitations. The quality of a LFA-stabilized mixture is highly dependent on the aggregates used. Generally, the lime-plus-fly ash content of a mixture ranges from 12 percent to 30 percent with lime-to- fly ash ratios of 1:3 to 1:4 being common. The critical engineering properties, namely strength, modulus of elasticity, Poisson's ratio, fatigue, autogenous healing volume changes and durability are influenced by the constituent materials and by proportions, processing, compaction, and curing. Test data correlated with theoretical analyses confirm that the load distribution characteristics of pavements with layers of LFA mixes are essentially those of a slab. It was found that the stiffer LFA layers distribute the load over large areas of the subgrade by the slab action, thus transmitting low vertical stress to the subgrade. The primary factors affecting the performance of LFA pavements were studied using scale models in laboratory and normal traffic conditions. Two types of construction related distress observed on LFA pavements were: distress when naterial becomes saturated before setting; distress when traffic causes cracks in partially set LFA material.

• Record URL:
  http://onlinepubs.trb.org/Onlinepubs/nchrp/nchrp_syn_37.pdf
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/NCHRP205Topic606
• Supplemental Notes:
  • 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.
• Corporate Authors:

  Transportation Research Board

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  Washington, DC  United States  20001
• Publication Date: 1976

Media Info

• Media Type: Digital/other
• Features: Appendices; Figures; Photos; References; Tables;
• Pagination: 66 p.
• Serial:
  • NCHRP Synthesis of Highway Practice
  • Issue Number: 37
  • Publisher: Transportation Research Board
  • ISSN: 0547-5570

Subject/Index Terms

• TRT Terms: Aggregates; Base course (Pavements); Defects; Lime fly ash; Load transfer; Mix design; Pavement distress; Pavement performance; Pavements; Paving; Properties of materials; Scale models; Soil stabilization; Subbase (Pavements)
• Uncontrolled Terms: Stabilization; Subbase
• Subject Areas: Bridges and other structures; Construction; Geotechnology; Highways; Materials; Pavements;

Filing Info

• Accession Number: 00142217
• Record Type: Publication
• ISBN: NCHRP 20-5 Topic 606
• Report/Paper Numbers: Final Rpt.
• Contract Numbers: HR20-5
• Files: TRIS, TRB, ATRI
• Created Date: Nov 23 1976 12:00AM