CLIFTON-HIGHLINE CANAL EXPERIMENTAL PROJECT NO 170-1 (14) 33 THIRD INTERIM REPORT

THE PERFORMANCE OF THE CLIFTON PROJECT IS DESCRIBED. THE PURPOSE IS TO EVALUATE VARIOUS TREATMENTS OF THE HIGHLY UNSTABLE SUBGRADE IN THE AREA. THE TREATMENTS CONSIST OF SUBEXCAVATION 2 FEET DEEP, THIN BACKFILL, LIME-TREATMENT, ASPHALT MEMBRANE AND THE STANDARD DESIGN. TO DATE NO MAJOR FAILURES HAVE OCCURRED AND NO SECTIONS HAVE BEEN REMOVED FROM TEST. HOWEVER, PAVEMENT SWELLING AND LINEAR CRACKING HAVE OCCURRED IN SOME AREAS INDICATING THE FIRST SIGNS OF FAILURE. MOISTURE ANALYSIS INDICATE THAT, IN ALL BUT THOSE SECTIONS WHOSE SUBGRADE IS PROTECTED WITH AN ASPHALT MEMBRANE, MOISTURE HAS ACCUMULATED IN THE BASE COURSE AND PRECIPITATED ONTO THE SHALE SUBGRADE. THIS MOISTURE IS GRADUALLY PENETRATING THE SHALE, CAUSING LOSS OF SUPPORT STRENGTH AND SWELLING. AS THE MOISTURE BUILDUP CONTINUES, PAVEMENT DEFLECTION, SWELLING AND CRACKING WILL INCREASE, PAVEMENT PROFILE WILL DETERIORATE AND SUBSEQUENT FAILURE WILL OCCUR. FAILURE WILL BEGIN TO BE OBSERVED DURING THE SPRING THAW OF 1972. IF THE SECTIONS WHOSE SUBGRADES ARE PROTECTED WITH THE MEMBRANE CONTINUE TO REMAIN STABLE, THIS TREATMENT WILL PROVE TO BE VERY EFFECTIVE AND RESULT IN ELIMINATING FUTURE EXPENSIVE MAINTENANCE REPAIR COSTS. /FHWA/

• Corporate Authors:

  Colorado Department of Highways

  4201 East Arkansas Avenue
  Denver, CO  United States  80222

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Publication Date: 0

Subject/Index Terms

• TRT Terms: Asphalt; Backfilling; Calcium oxide; Deflection; Failure; Moisture content; Pavement cracking; Pavements; Performance; Shale; Subgrade (Pavements); Swelling; Unstable soil
• Uncontrolled Terms: Membranes; Treatment
• Old TRIS Terms: Backfills; Membranes (Biology); Pavement deflection
• Subject Areas: Geotechnology; Highways; Pavements;

Filing Info

• Accession Number: 00206441
• Record Type: Publication
• Source Agency: Federal Highway Administration
• Files: TRIS, USDOT, STATEDOT
• Created Date: Aug 8 1971 12:00AM