A STUDY OF MULCHING PROCEDURES PERFORMED BY MAINE STATE HIGHWAY MAINTENANCE DIVISION

THIS STUDY CONSISTED OF OBSERVING THE MULCHING METHODS USED BY VARIOUS MULCH CREWS THROUGHOUT THE STATE OF MAINE. THE WORK CONSISTED OF OBSERVING THE CONDITIONS OF THE ROAD PRIOR TO MULCHING; DETERMINING THE REASON WHY THE WORK WAS DONE, AND WHY THE PARTICULAR TYPE AND GRADE OF BITUMEN WAS USED. A TIME STUDY WAS UNDERTAKEN TO NOTICE THE EQUIPMENT USED, TIME INVOLVED, AND METHODS USED BY EACH CREW. WHILE OBSERVING A PARTICULAR PROJECT, DATA WAS ALSO OBTAINED ON QUANTITIES OF AGGREGATE AND BITUMEN USED, AND THE LENGTH OF PROJECT INVOLVED. A SAMPLE OF THE COMPLETED MIXTURE WAS ALSO OBTAINED FOR LABORATORY ANALYSIS TO DETERMINE GRADATION, BITUMEN CONTENT, AND MOISTURE. IN THE LATE AUTUMN THE SAME PROJECTS WERE REVISITED AND EVALUATED. AS A RESULT OF THIS STUDY IT WAS FOUND THAT MANY ROADS WERE MULCHED EACH YEAR. IT WAS ALSO FOUND THAT IT COST $900 PER MILE TO DO THIS WORK. THIS STUDY INDICATED AND RECOMMENDS THAT ROADS CARRYING OVER 1200 VEHICLES PER DAY SHOULD BE SURFACED WITH A HOT PLANT MIX SURFACE TREATMENT BECAUSE MULCHING DOES NOT PROVIDE SUFFICIENT LASTING PROPERTIES. ROADS HAVING LESS TRAFFIC THAN 1200 VEHICLES PER DAY SHOULD BE MULCHED WITH A MIX PRODUCED IN A STABILIZATION PLANT. IT IS ESTIMATED THAT USING GRADERS. THIS STUDY TENDS TO INDICATE THAT MULCHES COMPOSED OF TARS DO NOT LAST AS WELL AS ASPHALT BASE MIXES. THE REASONS FOR THIS CONCLUSION WERE /1/ TAR MIXES WERE OFTEN EXCESSIVELY LEAN. /2/ TARS WERE USED ON HEAVILY TRAVELED ROADS AND AS A RESULT SUBJECTED TO EXCESSIVE WEAR. RESULTS WERE NOT AVAILABLE TO SHOW HOW CUTBACK ASPHALT WOULD PERFORM UNDER THE SAME CONDITIONS. COMMENTS FROM THE CREW FOREMEN AND SUPERVISORS INDICATED THAT THE VISCOSITY METHOD OF GRADING CUTBACKS WAS WELL ACCEPTED. IT WAS FOUND THAT MC- 800 WAS TOO HEAVY IF IT WAS BLENDED TO CONFORM TO THE MIDDLE OF THE VISCOSITY RANGE IN THE SPECIFICATIONS. IT CAN BE USED IF THE VISCOSITY IS HELD BELOW 900 CENTISTOKES AT 140 DEGREES F. /AUTHOR/ AT 140 DEGREE F. /AUTHOR/

• Supplemental Notes:
  • Hpr-1/3/, BPR-7, STATE-2-III-3
• Corporate Authors:

  Maine State Highway Commission

  Materials and Research Division, Bureau of Highways
  Augusta, ME  United States  04330
• Authors:
  • Rand, D W
• Publication Date: 1967-2

Subject/Index Terms

• TRT Terms: Aggregate gradation; Bitumen; Grading (Earthwork); Hot mix asphalt; Liquid asphalt; Methodology; Moisture content; Mulching; Pavements; Surfacing; Time and motion studies; Viscosity
• Uncontrolled Terms: Grading
• Old TRIS Terms: Cut back; Highway pavement
• Subject Areas: Design; Environment; Highways; Maintenance and Preservation; Pavements;

Filing Info

• Accession Number: 00218010
• Record Type: Publication
• Source Agency: Bureau of Public Roads /US
• Files: TRIS
• Created Date: Jul 5 1994 12:00AM