EFFECT OF ANTISTRIP ADDITIVES ON THE PROPERTIES OF POLYMER-MODIFIED ASPHALT BINDERS AND MIXTURES

The effect of liquid antistrip additives on the properties of polymer-modified asphalt binders and mixtures as related to rutting and moisture damage was investigated. The use of polymer-modified asphalts has increased in recent years because of their ability to resist rutting at high temperatures and improve fatigue resistance at low temperatures. In the Houston area liquid antistrip additives are used for almost all the mixtures to mitigate moisture damage. Liquid antistrip additives have been shown to soften certain asphalts. Whether liquid antistrip additives soften polymer-modified asphalts, thus degrading the rut resistant capability of polymer-modified asphalt, has become a concern to highway engineers. Asphalt binder properties known to have a bearing on rutting were evaluated on polymer-modified asphalts with three commercial liquid antistrip additives. Moisture damage of the mixture was evaluated using the conditioned-unconditioned indirect tensile test. In general, the liquid antistrip additives reduced the viscosity and softening point of polymer-modified asphalts, especially at high dosage. This will make polymer-modified asphalt binders more rut susceptible. For polymer-modified asphalt mixtures, increasing the dosage of liquid antistrip additives did not improve resistance to moisture susceptibility. On the basis of the investigation, lower dosages of liquid antistrip additives are recommended for polymer-modified asphalts than would be required for straight asphalts.

Language

  • English

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 108-114
  • Monograph Title: Asphalt concrete mix materials
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00669045
  • Record Type: Publication
  • ISBN: 030905513X
  • Files: TRIS, TRB
  • Created Date: Nov 23 1994 12:00AM