THERMAL COMPUTATIONS RELATED TO THE STUDY OF PAVEMENT COMPACTION CESSATION REQUIREMENTS AND DISCUSSION

TO ACHIEVE ADEQUATE COMPACTION OF HOT-MIX ASPHALT PAVEMENT, THE TEMPERATURE OF THE MAT MUST BE SUFFICIENTLY HIGH FOR THE PERIOD OF TIME NECESSARY TO COMPLETE ROLLING. INFORMATION DEVELOPED GIVES THE TIME NECESSARY TO COMPLETE ROLLING. INFORMATION DEVELOPED GIVES THE TIME REQUIRED TO COOL TO SEVERAL GIVEN AVERAGE MAT TEMPERATURES FOR MAT THICKNESSES OF 0.5 TO 8 INCHES AND LAYDOWN TEMPERATURES FROM 225 TO 300 F. OTHER PARAMETERS WERE ATMOSPHERIC TEMPERATURES FROM 10 TO 90 F AND INITIAL BASE TEMPERATURES FROM 10 TO 120 F, SOLAR FLUX FROM 50 TO 200 BTU/SQ FT/HR, AND WIND VELOCITIES OF 10 AND 20 KNOTS. TO TEST THE EFFECT OF BASE PROPERTIES ON THE HEAT LOSS FROM THE HOT-MIX ASPHALT MAT, SAMPLE CALCULATIONS WERE PERFORMED FOR VARIOUS TYPE SUBGRADE MATERIALS. COOLING RATES DO NOT DIFFER MARKEDLY FOR A BASE OF ASPHALT, CLAY, SAND-CLAY, OR FOR EARTH WITH A LOW THERMAL CONDUCTIVITY. HOWEVER, FOR A MOIST EARTH, RESULTS SHOW A SIGNIFICANT INCREASE IN HEAT TRANSFER RATE INTO THE BASE. THESE DATA WERE OBTAINED BY FINITE DIFFERENCE COMPUTER SOLUTIONS OF THE GOVERNING ENERGY EQUATIONS IN THE MAT AND BASE WITH APPROPRIATE BOUNDARY CONDITIONS. THE SOLUTION YIELDS TEMPERATURES IN THE MAT AND BASE AS FUNCTIONS OF POSITION AND TIME. FROM THESE COMPUTED DATA, TIMES TO COOL TO GIVEN AVERAGE TEMPERATURE ARE OBTAINED. /AUTHOR/

• Supplemental Notes:
  • Vol 39, pp 377-403, 14 FIG, 1 TAB, 6 REF, 1 APP
• Authors:
  • Dickson, P F
  • Corlew, J S
• Conference:
  • Association of Asphalt Paving Technologists Proc
• Publication Date: 1970

Subject/Index Terms

• TRT Terms: Bituminous pavements; Compaction; Cooling; Finite differences; Hot mix asphalt; Information processing; Mat footings; Subgrade materials; Temperature; Thermal analysis
• Uncontrolled Terms: Mats
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00211661
• Record Type: Publication
• Files: TRIS
• Created Date: Jul 25 1971 12:00AM