This paper presents the essential results of a more extensive investigation into the effects of adding hydrated lime to asphalt and aggregate mixes. Laboratory samples, designed and prepared with mixes of hydrated lime, aggregate, and asphalt, were used to monitor interactions among the various bituminous mixtures over time. The sample combinations were in compliance with a design comprising three asphalts (AC-10, AC-15, and AC-20), two aggregates (judged as good and poor performers by field experience), two sources of lime (Utah and South Dakota), and three concentrations of lime (0.0, 0.5, and 1.0 percent). For each combination, 21 samples were prepared that allowed three test replications of each category of bituminous mixture to span seven age-test periods (24 hours, 10 days, 3 months, 6 months, 12 months, 18 months, and 2 years). Test samples were aged by exposure to the weather in Salt Lake City. Viscosity increased with age, with the rate of increase higher with the higher AC asphalts (However, increases for the AC-10 and AC-15 asphalts are approximately equal after 6 months to a year.), although viscosity was retarded in direct proportion to the amount of lime added, with mixes with relatively poor aggregates being affected most. Ductility values were approximately 44 percent higher for asphalts with lime added. Measurements of immersion compression (IC) indicate that the influence of aggregate type and concentrations of lime on IC has a much greater effect than the type of asphalt as type of lime used. In fact, the type of lime used seem to have little if any effect on mix properties. Overall, the tests revealed two potential benefits occurring with hydrated lime supplements: an increase of mix stability and a decrease in flow, as well as decreased hardening rates of the asphalt binder.

Media Info

  • Media Type: Print
  • Pagination: pp 44-45
  • Monograph Title: Bituminous concrete materials, mixtures, and additives
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00185295
  • Record Type: Publication
  • ISBN: 0309026881
  • Files: TRIS, TRB
  • Created Date: Jan 13 1979 12:00AM