Lignin as Antioxidant: Limited Study on Asphalts Frequently Used on Kansas Roads

For 2004, the binders most frequently used to pave Kansas roads were identified, using the method of "Reduced Sampling," to be one modified binder (reportedly PG 76-28), and eight unmodified binders (seven were PG 64-22, and one PG 70-22). The eight unmodified binders were ranked according to a number of tests to select the least-likely-to-age binder and the most-likely-to-age binder. These two selected binders were mixed with the calculated amount of lignin GE15 or lignin B108 to give a lignin concentration of 0, 2, 4, 7, and 10 percent. The two percent lignin concentration offered a limited improvement in the aging index, AI @ 25°C, and the 10 percent level could be detrimental to the desired effect. The most improvement in AI @ 25°C occurred at the four and seven percent lignin; the most-likely-to-age binder showed essentially the same degree of benefit at both concentrations and for both lignins, but the least-likely-to-age binder required the higher concentration of seven percent of either lignin to show a significant improvement in AI @ 25°C. Also, at the four and seven percent lignin, the high critical temperature, TC, intermediate TC, and low TC either remained essentially unchanged or exhibited a limited variation from the control value. The PG 76-28 modified binder containing two percent lignin showed an improvement in AI @ 25°C of 11 and 24 percent for lignin GE15 and lignin B108, respectively; a higher concentration of four percent of either lignin reversed the trend of improving the AI @ 25°C. Lignin, a byproduct and waste material, showed potential as an antioxidant for asphalts.

• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Robertson, Raymond E
  • Bishara, Safwat Wahba
  • Mahoney, Donna
• Conference:
  • Transportation Research Board 85th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2006-1-22 to 2006-1-26
• Date: 2006

Language

• English

Media Info

• Media Type: CD-ROM
• Features: Figures; References; Tables;
• Pagination: 23p
• Monograph Title: TRB 85th Annual Meeting Compendium of Papers CD-ROM

Subject/Index Terms

• TRT Terms: Asphalt; Asphalt additives; Asphalt based materials; Asphalt mixtures; Asphalt pavements; Binder content; Binders; Bituminous binders; Road materials; Roads
• Subject Areas: Construction; Design; Geotechnology; Highways; Materials; Pavements; I22: Design of Pavements, Railways and Guideways; I30: Materials; I33: Other Materials used in Pavement Layers;

Filing Info

• Accession Number: 01025564
• Record Type: Publication
• Report/Paper Numbers: 06-0254
• Files: TRIS, TRB
• Created Date: Jun 8 2006 11:25AM