This report evaluates and recommends changes to existing Alabama Highway Department material test methods, specifications and design criteria for geotextile lined longitudinal roadway drains. Laboratory studies investigated current and proposed textile strength methods and recommended the ASTM puncture type test as more applicable to this end use because the geotextile is generally loaded biaxially while in service. The study results indicated that fabric permeabilities should be compared with each other on a flow rate per layer basis rather than a flow rate per unit thickness. Because of the relatively high permeability and small pore sizes in currently available geotextiles, these criteria are not too critical when used in underdrains having roadway base permeabilities of about 10 -4 cm/sec. Laboratory clogging tests and field observations led to the conclusion that properly constructed drain systems act more as a soil retention device than a filter. A geotextile lined drain will probably not clog with time except in areas where pumping occurs. Field studies on a four mile section of drain showed that the system would begin to function with a relatively small rainfall and stop drainage within 24 to 48 hours after even a heavy rain.

  • Corporate Authors:

    University of Alabama, University

    P.O. Box 1968
    University, AL  United States  35486

    Alabama State Highway Department

    11 South Union Street
    Montgomery, AL  United States  36130

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • BALL, J
    • MILLER, K
    • Scofield, R
    • McMinn, J
  • Publication Date: 1980-3-7

Media Info

  • Features: Appendices; Figures; References; Tables;
  • Pagination: 130 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00335481
  • Record Type: Publication
  • Report/Paper Numbers: FHWA/AL-80/091 Final Rpt.
  • Contract Numbers: 91, 930-089
  • Created Date: Oct 28 1981 12:00AM