Ground tire rubber as a stabilizer for subgrade soils.

Details

• Creators:
  Cosentino, Paul J. ; Bleakley, Albert M. ; Armstrong, Alexander T. ; Misilo, Thaddeus J. ; Sajjadi, Amir M.
• Corporate Creators:
  Florida Institute of Technology. Civil Engineering Dept.
• Subject/TRT Terms:
  Base Course (Pavements) Crumb Rubber Geotechnical Engineering Reclaimed Rubber Soil Stabilization Subgrade Materials
• Publication/ Report Number:
  BDK81 977-03
• Resource Type:
  Tech Report
• Geographical Coverage:
  Florida
• Corporate Publisher:
  Florida. Dept. of Transportation. Research Center
• Abstract:
  Over 250 million scrap tires are generated annually in the U.S. Historically, a significant portion of these tires
  
  have been processed into finely ground tire rubber (GTR), or crumb rubber, for use as an additive in hot mix asphalt
  
  (HMA) pavements to improve pavement performance. Recently, improved synthetic polymer additives have been
  
  developed that more economically provide the same performance improvements as GTR. This development has
  
  decreased the demand for GTR in HMA, potentially freeing supplies of GTR for other applications.
  
  Over the past two decades, the Florida Department of Transportation (FDOT) has conducted a significant amount
  
  of research on ways to re-use waste materials such as energy generation ash, tires, glass, reclaimed asphalt pavement,
  
  and reclaimed concrete in roadway construction. FDOT initiated this study to investigate whether blending GTR with
  
  subgrade soils would be a beneficial practice.
  
  The objective of this research was to determine the effect of GTR on subgrade soil engineering properties. Three
  
  representative sizes of GTR, 1 inch (25.4 mm), 3/8 inch (9.51 mm), and #40 (0.422 mm) were blended in varying
  
  percentages with three subgrade soils. Subgrade soils were selected with low, medium, and high limerock bearing ratio
  
  (LBR) strength. Blends were evaluated with 4, 8, 16, 24, and 32% GTR by volume. Blends were evaluated for grain
  
  size, moisture-density, LBR, permeability, consolidation, resilient modulus (Mr), and creep.
  
  Ground tire rubber does not make a good stabilizing agent for subgrade soils. Blending GTR with subgrade soils
  
  reduced both LBR and Mr significantly. Blending has minimal impact on consolidation or permeability. Blending
  
  increases creep in the tested soils, however the creep remained within acceptable limits.
  
  Blending GTR with soil did reduce the density of the blend. Additional research should be conducted to evaluate
  
  whether soil/GTR blends would be suitable for low-density fill applications where the benefits from reduction in
  
  vertical and horizontal soil pressures would offset the reduction in strength.
  
  
• Format:
  PDF
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:b782d5f7a51cc87ef851428e615cf3830d785ef96b40dc208c9aebda4a941212
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/27311/dot_27311_DS1.pdf
• File Type:
  [PDF - 6.17 MB ]