A STUDY OF CESSATION REQUIREMENTS FOR CONSTRUCTING HOT MIX ASPHALT PAVEMENTS

CURRENTLY, PLACING OF NOT-MIX ASPHALT PAVEMENT IS STOPPED WHEN THE AIR TEMPERATURE FALLS BELOW A CERTAIN VALUE. A MORE LOGICAL REQUIREMENT WOULD BE TO STOP PLACING WHEN CONDITIONS ARE SUCH THAT THE CONTRACTOR WILL NOT HAVE A "REASONABLE" TIME" TO COMPACT THE PAVEMENT BEFORE IT COOLS TO WHERE IT CANNOT BE COMPACTED. CORLEW AND DICKSON DEVELOPED A MATHEMATICAL MODEL OF THE LOSS OF HEAT FROM A MAT THAT CONSIDERS LAYDOWN TEMPERATURE, MAT THICKNESS, AIR TEMPERATURE, WIND VELOCITY, AND SOLAR FLUX. THE MODEL WAS USED TO PRODUCE COOLING CURVES FOR MAT THICKNESSES FROM 1/2 TO 8 IN., LAYDOWN TEMPERATURE FROM 225 TO 300 F, AND A RANGE OF ENVIRONMENTAL CONDITIONS. THE MATHEMATICAL MODEL SHOWS THAT LAYDOWN TEMPERATURE AND MAT THICKNESS ARE FAR MORE IMPORTANT IN DETERMINING HOW FAST THE MAT WILL COOL THAN THE ENVIRONMENTAL CONDITIONS. A METHOD IS SUGGESTED WHEREBY THESE DATA CAN BE USED TO ESTABLISH CESSATION REQUIREMENTS THAT WOULD PERMIT PAVING WHEN THE CONTRACTOR WOULD HAVE A REASONABLE TIME TO APPLY ROLLING BEFORE THE MAT COOLS AND WOULD STOP PAVING WHEN HE DOES NOT HAVE ENOUGH TIME. THE SUGGESTED CESSATION REQUIREMENTS SHOW THAT A REQUIREMENT BASED ON A SINGLE LIMITING AIR TEMPERATURE IS NOT ADEQUATE TO ENSURE THAT PAVING IS PERMITTED ONLY WHEN CONDITIONS ARE SATISFACTORY. LAYDOWN TEMPERATURE AND MAT THICKNESS MUST BE CONSIDERED AS WELL AS THE ENVIRONMENT. THE DATA ALSO SHOW CLEARLY THE NEED TO APPLY BREAKDOWN ROLLING AS QUICKLY AS PRACTICABLE TO ENSURE QUALITY PAVEMENTS. /AUTHOR/

• Record URL:
  • http://onlinepubs.trb.org/Onlinepubs/hrr/1970/316/316-006.pdf
• Supplemental Notes:
  • Paper sponsored by Committee on Construction Practices--Flexible Pavement and presented at the 49th Annual Meeting. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.
• Authors:
  • Foster, Charles R
• Publication Date: 1970

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: pp 70-75
• Monograph Title: Construction and construction equipment
• Serial:
  • Highway Research Record
  • Issue Number: 316
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Hot mix asphalt; Mathematical models; Mechanical failure; Rolling; Temperature; Thickness
• Old TRIS Terms: Breakdown
• Subject Areas: Construction; Highways;

Filing Info

• Accession Number: 00215350
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Nov 9 1970 12:00AM