Materials, Specifications, and Construction Techniques for Heavy-Duty Flexible Bases: Literature Review and Status Report on Experimental Sections

For the majority of the Texas highways the granular base layer is the main structural component of the pavement system. Project 0-4358 was initiated to provide Texas Department of Transportation (TxDOT) guidelines to improve its base specifications in order to better withstand the demands of future traffic loads. This report provides the results of a literature search and a survey of the performance of experimental heavy-duty base pavements recently constructed in Texas. Base specifications and construction practices from eight United States (U.S.) Department of Transportations (DOTs) and two overseas countries were compared with TxDOT current and proposed specifications. Currently, TxDOT is the only agency that does not control the amount of fines (minus 200 fraction) in its bases. Research studies have indicated that high levels of minus 200 can severely impact both moisture susceptibility and cold weather performance. The newly proposed TxDOT specifications with limits on the fines content are in line with the practices of other agencies in similar climates. The results from three experimental sections on US-281, US-77 and FM-1810 provide several important observations about current base performance. The use of small amounts of stabilizer to upgrade marginal materials does not always guarantee a top-quality base. Better methods of selecting optimal stabilizer content are needed. Furthermore, the flexible bases with high fines content appear to have high initial field stiffnesses that decease rapidly with time.

• Supplemental Notes:
  • Project Title: Materials, Specifications, and Construction Techniques for Heavy-Duty Flexible Bases. Report Date: October 2002; Resubmitted: July 2005.
• Corporate Authors:

  Texas Transportation Institute

  Texas A&M University System, 3135 TAMU
  College Station, TX  United States  77843-3135

  Texas Department of Transportation

  Research and Technology Implementation Office, P.O. Box 5080
  Austin, TX  United States  78763-5080

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Hefer, Arno
  • Scullion, Tom
• Publication Date: 2005-7

Language

• English

Media Info

• Media Type: Print
• Edition: Technical Report
• Features: Appendices; Figures; Photos; References; Tables;
• Pagination: 154p

Subject/Index Terms

• TRT Terms: Base course (Pavements); Fines (Materials); Flexible pavements; Granular bases; Literature reviews; Materials; Pavement performance; Research reports; Road construction; Soil stabilization; Specifications; Surveys; Traffic loads
• Uncontrolled Terms: Moisture susceptibility
• Geographic Terms: Texas
• Subject Areas: Construction; Design; Freight Transportation; Geotechnology; Highways; Materials; Pavements; I22: Design of Pavements, Railways and Guideways; I42: Soil Mechanics; I52: Construction of Pavements and Surfacings;

Filing Info

• Accession Number: 01022656
• Record Type: Publication
• Report/Paper Numbers: FHWA/TX-03/0-4358-1, Report 0-4358-1
• Contract Numbers: Project No. 0-4358
• Files: TRIS, USDOT, STATEDOT
• Created Date: Apr 7 2006 2:02PM