A rapid evaluation of the rate of curing of winter seals

Binder that has been cut back can promote early adhesion at lower temperatures, during so-called “winter sealing”. However, the effect of excessive cutter on seal performance may be seen as flushing and/or shoving of the seal. The ideal situation to strive for would be the presence of sufficient cutter in the winter to promote adhesion, followed by the loss of volatile components, so that sufficient loss of cutter by summer would result in a minimal risk of flushing, bleeding or shoving. The conventional method of evaluating the level of cutters present in the in situ seal binders is through monitoring the change in softening point (ring and ball) of those binders. This would require the recovery of the binders. However, such an approach faces a number of difficulties, including that the conventional method of recovery would result in the loss of volatile components, affecting the results. Other specialized, time-consuming recovery methods are required, and they are beyond the capabilities of most standard laboratories. Moreover, sampling for softening point analysis is difficult because large samples are required for binder recovery, involving labour intensive sample collection which results in damage to the seal surface; and when a seal is placed on top of an older seal or asphalt surface, it is difficult to remove the upper seal binder selectively. This paper investigates the use of gas chromatography in assessing the rate of dissipation of volatile components from cutback binders used in winter seals. Such a method is demonstrated to be a rapid and effective indicator of the level of volatile components remaining in the winter seal. After investigating a number of sites and seal types, results indicate that, for the trials investigated, most volatile components have dissipated after the first summer season had passed.


  • English

Media Info

  • Pagination: 10p
  • Monograph Title: 11th Conference on Asphalt Pavements for Southern Africa: CAPSA15, 16-19 August 2015, Sun City, South Africa

Subject/Index Terms

Filing Info

  • Accession Number: 01597139
  • Record Type: Publication
  • Source Agency: ARRB
  • Files: ATRI
  • Created Date: Apr 22 2016 11:16AM