Evaluation of Field Projects Using Crumb Rubber Modified Asphaltic Concrete

In 1994, the Louisiana Department of Transportation and Development (LADOTD) initiated a research project to evaluate different crumb-rubber modified (CRM) applications in which the long-term pavement performance of the CRM asphalt pavements was compared to that of the control sections built with conventional asphalt mixtures. This report presents a laboratory, construction, and field performance evaluation study of several applications of CRM hot-mix asphalt in Louisiana. Eight CRM asphalt pavement sections were constructed using eight different CRM processes or applications. Five state highway projects were selected to construct these eight CRM sections. A control section was built with conventional asphalt mixtures on each project to compare the field performance of pavement sections built with CRM asphalt mixtures. To evaluate the mixture characteristics of the CRM and conventional mixes, laboratory tests of Marshall stability and flow, indirect tensile strength (ITS) and strain, and indirect tensile resilient modulus (M sub R) were conducted on field compacted Marshall specimens. Comparisons of the construction and field performance of the pavements were achieved through roadway core air void analysis, rut-depth measurement, international roughness index (IRI), pavement structure numbers measured through the DYNAFLECT system, and Quality Control data. Also, the final field performance evaluation used visual data acquired from Louisiana's Pavement Management Section in which the international roughness index (IRI), rut-depth measurements, and crack data were evaluated. Also, visual inspection of cracks was reported. The result of this study indicated that the conventional mixtures exhibited higher laboratory strength characteristics than the CRM mixtures. The pavement sections constructed with CRM asphalt mixtures showed overall better field performance indices (rut depth, random cracks, and IRI numbers) than corresponding control sections. Both CRM modified, wet and dry, hot mix asphalt (HMA) mix types are performing equally well, if not better, than the conventional mix types evaluated.

• Record URL:
  • https://www.ltrc.lsu.edu/pdf/2007/fr_393.pdf
• 
• Corporate Authors:

  Louisiana Transportation Research Center

  4101 Gourrier Avenue
  Baton Rouge, LA  United States  70808

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Cooper Jr, Samuel B
  • Mohammad, Louay N
  • Abadie, Chris
• Publication Date: 2007-3

Language

• English

Media Info

• Media Type: Print
• Edition: Final Report
• Features: Appendices; CD-ROM; Figures; Maps; References; Tables;
• Pagination: 111p

Subject/Index Terms

• TRT Terms: Air voids; Asphalt concrete; Asphalt pavements; Cracking; Crumb rubber; Hot mix asphalt; Laboratory tests; Modulus of resilience; Pavement performance; Tensile strength
• Identifier Terms: International Roughness Index
• Uncontrolled Terms: Rut depth
• Geographic Terms: Louisiana
• Subject Areas: Design; Highways; Materials; Pavements; I22: Design of Pavements, Railways and Guideways; I23: Properties of Road Surfaces; I31: Bituminous Binders and Materials;

Filing Info

• Accession Number: 01053567
• Record Type: Publication
• Report/Paper Numbers: FHWA/LA.04/393
• Contract Numbers: State Project: 736-99-0762; LTRC Project: 95-5B
• Files: TRIS, USDOT
• Created Date: Jul 18 2007 3:36PM