EDDINGTON EXPERIMENTAL PROJECT

THE PERFORMANCE IS DESCRIBED ON FROST-SUSCEPTIBLE SOILS IN A SECONDARY ROAD IN' /1/ BITUMINOUS-ENVELOPE BASE FOR THREE SECTIONS OF FLEXIBLE PAVEMENT, AND /2/ 8 CULVERTS WITH VARIOUS CONDITIONS OF BACKFILLING AND BEDDING. THE BITUMINOUS ENVELOPES WERE COMPOSED OF MIXTURES OF RT-6 AND CRUSHED GRAVEL-SAND AGGREGATE, WITH A DESIGNED THICKNESS OF 2 INCHES, AND COVERED WITH 2-IN. BITUMINOUS-GRAVEL SURFACING. THE ENVELOPED SOIL RANGED FROM SILTY SAND TO SILTY SANDY GRAVEL, AND THE SUBGRADE SOIL RANGED FROM SANDY SILT TO SILTY GRAVEL. THE PERFORMANCE OF THE TREATED SECTIONS WAS COMPARED TO ADJACENT SECTIONS HAVING GRAVEL BASE COURSE OF CONVENTIONAL DESIGN. THE CULVERTS WERE OF CORRUGATED METAL PIPE. TYPES OF EMBEDMENT RANGED FROM NATURAL PARENT SOIL/NORMALLY SILTY SAND TO SILTY GRAVEL/ TO GRAVEL, AND THE BACKFILL RANGED FROM NATURAL PARENT MATERIAL TO GRAVEL PLACED IN TRAPEZOIDAL TRENCHES. PRECIPITATION IN THE NOV-APR PERIOD, RANGED FROM 15-28 IN. AT DOW AIR FORCE BASE, ABOUT 6-8 MILES FROM THE EXPERIMENTAL PROJECT. THE ANNUAL FREEZING INDEX AVERAGED 1,372 DEGREE-DAYS. THE AVERAGE DAILY TRAFFIC ON THE ROAD RANGED FROM ABOUT 700 IN 1950 TO 1,685 IN 1965. ELEVATION READINGS WERE TAKEN AT 50-FT. INTERVALS ON THE CENTERLINE AND EACH EDGE OF THE PAVEMENT OF THE EXPERIMENTAL SECTIONS. BENKELMAN BEAM DEFLECTION MEASUREMENTS WERE MADE IN THE FALL AND 5 TIMES DURING THE SPRING BREAK-UP PERIOD. MAJOR CONCLUSIONS REGARDING BITUMINOUS ENVELOPE WERE' /1/ ENVELOPE SECTIONS USUALLY HAD A GREATER AMOUNT OF FROST HEAVE THAN THE ADJACENT GRAVEL-BASE SECTIONS, /2/ THE MAGNITUDE OF HEAVE WAS ABOUT THE SAME FOR THE 24-IN. AS FOR THE 18-IN. BITUMINOUS ENVELOPE BASE, /3/ BENEKELMAN BEAM DEFELCTIONS WERE ABOUT THE SAME FOR BOTH SECTIONS, /4/ BENKELMAN BEAM DEFLECTIONS ALONG THE CENTERLINE DURING THE SPRING BREAK-UP PERIOD WERE GREATER FOR THE ENVELOPE SECTIONS THAN FOR ADJACENT GRAVEL-BASE SECTIONS, /5/ BITUMINOUS-ENVELOPE BASE CONSTRUCTION IS CONSIDERED TO BE ECONOMICALLY PRACTICAL IN AREAS OF MAINE WHERE OVERHAUL DISTANCES EXCEED 15 MILES. THE CONCLUSION REGRADING CULVERTS WAS THAT THOSE BEDDED ON EXISTING PARENT MATERIAL AND BACKFILLED WITH GRAVEL, AND HAVING A BLEEDER SYSTEM TO DRAIN WATER TOWARD THE ENDS OF THE CULVERT, WERE MOST DESIRABLE.

  • Corporate Authors:

    Maine State Highway Commission

    Materials and Research Division, Bureau of Highways
    Augusta, ME  United States  04330
  • Authors:
    • Ault, J G
  • Publication Date: 1966-6

Subject/Index Terms

Filing Info

  • Accession Number: 00230600
  • Record Type: Publication
  • Source Agency: Bureau of Public Roads /US
  • Report/Paper Numbers: Hpr-pr-1/1/
  • Files: TRIS
  • Created Date: Aug 15 2004 2:19AM