ROAD SWELLS: CAUSES AND CURES

HIGHWAY SWELLS HAVE LONG PLAGUED DRIVERS AND HIGHWAY ENGINEERS IN COLORADO AND OTHER WESTERN STATES. FOR SOME TIME, IT HAS BEEN KNOWN THAT THESE ROADS LIE OVER SOILS THAT SWELL ON CONTACT WITH WATER. THE PROBLEM HAS BEEN TO LOCATE THE SOURCE OF THE WATER. HOW AMBIENT AIR PENETRATES THE POROUS SHOULDERS OF A ROAD IS SHOWN. PART OF THE WATER VAPOR IS CONVERTED TO LIQUID WATER, WHICH COLLECTS ON THE SURFACES OF THE AGGREGATE PARTICLES AND TRICKLES INTO THE SHALE. OVER A PERIOD OF MONTHS OR YEARS THE SUBGRADE SOAKS UP THE SUBBASE AND CREATES A SWELL. THE COLORADO HIGHWAY DEPARTMENT HAS DEVELOPED TWO APPROACHES TO SOLVING THE PROBLEM: LAYING DOWN A WATERPROOF ASPHALT MEMBRANE BETWEEN THE SHALE SUBGRADE AND THE ROAD SUBBASE, OR USING FULL-DEPTH ASPHALT FOR THE ROAD. OTHER HIGHWAY DEPARTMENTS HAVE TRIED TO TREAT THE SUBGRADE SOIL BEFORE THE ROAD IS BUILT, HOPING TO CURB THE SOIL'S TENDENCY TO SWELL ON CONTACT WITH WATER. THESE EFFORTS HAVE NOT PROVED VERY SUCESSFUL, HOWEVER. /AUTHOR/

  • Availability:
  • Supplemental Notes:
    • Vol 40, No 12, PP 48-50
  • Authors:
    • Brakey, B A
  • Publication Date: 1970-12

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Filing Info

  • Accession Number: 00203520
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Feb 12 1971 12:00AM