LOW-TEMPERATURE FRACTURE TOUGHNESS OF POLYETHYLENE-MODIFIED ASPHALT BINDERS

One of the key factors that determines the susceptibility of a pavement to thermal cracking is the ability of the binder to withstand or relieve thermal stresses before they reach a critical point where cracks form. The mechanisms by which the addition of polyethylene improves the low-temperature properties of asphalt binders are discussed. Also examined is the degree to which the quality of the additive dispersion influences these mechanisms. Notched bending beam tests conducted at -20 deg C yielded fracture toughness values for three different polyethylene-asphalt systems. In all systems studied, the fracture toughness was found to increase linearly with the additive content. The chlorinated polyethylene-modified binders produced the toughest samples, followed by the stabilized polyethylene and the unstabilized polyethylene binders, respectively. High-magnification photographs, made with an environmental scanning electron microscope, yielded additional information concerning the nature of the failure mechanisms in these systems. The combined results show that greater toughening occurs with more finely dispersed polymers and with greater compatibility at the interface between the polymer and the asphalt matrix. These observations are consistent with the mechanisms of crack pinning and shear yielding, both of which are regularly found in multiphase thermoplastic materials.

• Record URL:
  http://onlinepubs.trb.org/Onlinepubs/trr/1994/1436/1436-007.pdf
• Record URL:
  https://scholar.google.com/scholar_lookup?title=LOW-TEMPERATURE+FRACTURE+TOUGHNESS+OF+POLYETHYLENE-MODIFIED+ASPHALT+BINDERS&author=N.+Lee&author=S.+Hesp&publication_year=1994
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/030905513X
• Supplemental Notes:
  • This paper appears in Transportation Research Record No. 1436, Asphalt Concrete Mix Materials. 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:
  • Lee, Nolan K
  • Hesp, Simon A M
• Publication Date: 1994-10

Language

• English

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 54-59
• Monograph Title: Asphalt concrete mix materials
• Serial:
  • Transportation Research Record
  • Issue Number: 1436
  • Publisher: Transportation Research Board
  • ISSN: 0361-1981

Subject/Index Terms

• TRT Terms: Asphalt; Ethylene resins; Failure; Fracture properties; Low temperature; Testing
• Uncontrolled Terms: Polyethylene
• Subject Areas: Highways; Materials; I31: Bituminous Binders and Materials;

Filing Info

• Accession Number: 00669039
• Record Type: Publication
• ISBN: 030905513X
• Files: TRIS, TRB
• Created Date: Nov 23 1994 12:00AM