INVESTIGATION OF THE EFFECTS OF HOLDING HOT BITUMINOUS MIXTURES IN STORAGE HOPPERS FOR SHORT AND EXTENDED PERIODS OF TIME

THE PURPOSE OF THIS INVESTIGATION WAS TO DETERMINE THE FEASIBILITY OF BUILDING HOT-MIX STORAGE SILOS, EITHER AT THE MIXING PLANT OR AT A DISTANT LOCATION, TO ACT AS A SATELLITE PLANT. THE ADVANTAGES OF USING SUCH A SYSTEM ARE EVIDENT. IT ASSURES A MORE CONTINUOUS OPERATION AND FEWER SHUTDOWNS OF THE PLANT, RESULTING IN HIGHER PRODUCTION AND LOWER COST OF PLANT OPERATION. THE COST OF TRUCKING IS REDUCED BY REQUIRING FEWER TRUCKS FOR ANY PARTICULAR PROJECT, DUE TO INSTANT LOADING. ALSO, IT ACHIEVES A MORE UNIFORM PRODUCT AND BETTER TEMPERATURE CONTROL WITH A CONTINUOUS OPERATION. THE STORAGE OF HOT BITUMINOUS CONCRETE FOR EXTENDED PERIODS OF TIME IS CONTROVERSIAL AND POINTS TO THE NEED FOR MORE RESEARCH. IT IS THE CONSENSUS OF OPINION THAT SURGE HOPPERS HOLDING THE MIX FOR A RELATIVELY SHORT PERIOD OF TIME (HRS) ARE PRACTICAL AND TEND TO INCREASE THE OVERALL EFFICIENCY OF THE PLANT. COARSE OPEN-GRADED MIXTURES APPEAR TO HARDEN AT A FASTER RATE THAN DENSE GRADED MIXTURES. BASED ON THIS INVESTIGATION, THE OPINION WAS THAT ASPHALT IN HOT BITUMINOUS MIXTURES HARDENS SIGNIFICANTLY AT TEMPERATURES BETWEEN 325 DEGREES F AND 250 DEGREES F. THIS PROCESS IS CONTINUOUS AND IS PRIMARILY A FUNCTION OF TEMPERATURE AND TIME. ANY SUBSTANTIAL HARDENING MUST BE REGARDED AS UNDESIRABLE. TESTS WERE CARRIED ON WITHOUT THE USE OF INERT GASES OR ASPHALT ADDITIVES SUCH AS OXIDATION INHIBITORS OR ANTI-HARDENING AGENTS. /CGRA/

• Supplemental Notes:
  • Vol 11, 237-248 PP, 3 FIG, 2 PHOT, 2 REF
• Authors:
  • Tuttle, L
• Publication Date: 1966-11

Media Info

• Serial:
  • Canadian Technical Asphalt Association, Proceeding
  • Publisher: POLYSCIENCE PUBLICATIONS INC.

Subject/Index Terms

• TRT Terms: Asphalt concrete; Bituminous materials; Concrete hardening; Economics; Hardness; Heating (Structures); Hoppers; Hot mix asphalt; Industrial plants; Manufactures; Manufacturing; Mixing plants; Storage tanks; Temperature control (Structures); Time; Trucking
• Old TRIS Terms: Plant efficiencies
• Subject Areas: Economics; Freight Transportation; Highways; Materials; Motor Carriers;

Filing Info

• Accession Number: 00210569
• Record Type: Publication
• Source Agency: CANADIAN GOOD ROADS ASSOCIATION
• Files: TRIS
• Created Date: Jan 31 1994 12:00AM