FIBER-MODIFIED ASPHALT OVERLAYS

The addition of fibers into asphalt mixes has two main effects, both of which improve cracking resistance. The first of these effects is increased binder content, due to the capacity of the fibers to hold large quantities of bitumen. The second is higher shear resistance, resulting from the reinforcement provided by the fibers. Fiber-modified asphalt concrete, used as a thin wearing course, has proved to retard reflective cracking. Another application of this technique is fiberized sand-asphalt, which is used as a stress-absorbing interlayer. Two-layered overlays, incorporating one or two types of fiber-modified mix, have also been developed. One of these composite overlays combines a thin lift of fiber-modified asphalt concrete, acting as a stress relieving interlayer, and a thin wearing course, designed for high skid resistance. Another type, seen as the most effective in terms of crack prevention, consists of two layers of fiberized asphalt, the lower being a high binder content sand-asphalt and the wearing course a fiber-modified gap-graded, dense mix. The laboratory characteristics of these materials are presented and discussed. This includes the evaluation of the resistance to cracking of specimens of single or double-layered systems, subjected to simultaneous dynamic bending and gradual crack opening. Finally, the in-place behaviour of the different types of overlay has been monitored for a number of years. Relationships between laboratory and in situ performance have been established, facilitating the selection of the most appropriate overlay for a given case. For the covering abstract see ITRD E109276.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/2912143144
• Corporate Authors:

  RILEM PUBLICATIONS

  61 AVENUE DU PRESIDENT WILSON
  CACHAN CEDEX,   France  F-94235
• Authors:
  • Serfass, J P
  • MAHE DE LA VILLEGLE, B
• Conference:
  • REFLECTIVE CRACKING IN PAVEMENTS - RESEARCH IN PRACTICE. PROCEEDINGS OF THE 4TH INTERNATIONAL RILEM CONFERENCE, 26-30 MARCH 2000, OTTAWA, CANADA
• Publication Date: 2000

Language

• English

Media Info

• Features: References;
• Pagination: p. 227-39

Subject/Index Terms

• TRT Terms: Bitumen; Cracking; Fibers; Pavements; Prevention
• Uncontrolled Terms: Modifications
• ITRD Terms: 4963: Bitumen; 5211: Cracking; 4557: Fibre; 9048: Modification; 2955: Pavement; 9149: Prevention
• Subject Areas: Highways; Pavements; Security and Emergencies;

Filing Info

• Accession Number: 00812941
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• ISBN: 2-912143-14-4
• Files: ITRD, ATRI
• Created Date: Jul 2 2001 12:00AM