A Comparative Subgrade Evaluation Using CBR, Vane Shear, Light Weight Deflectometer, and Resilient Modulus Tests

California Bearing Ratio (CBR) is generally used in airport pavement thickness design procedures to characterize subgrade soils. Alternative thickness design procedure based on layered elastic analysis has also been available (LEDFAA) since 1995 which accepts either subgrade CBR or resilient modulus. The CBR value is converted to resilient modulus in psi by multiplying by 1,500. The relationship is based on a correlation between dynamic modulus and CBR measured for soils and aggregates. A strong trend is apparent in the correlation but there is a lot of scatter. Resilient modulus, in combination with a measure of strength such as shear, could displace CBR as a means of characterizing subgrade soils. Therefore, it is necessary to understand and document the relationships between CBR and other methods of characterizing soils. This study summarizes the preliminary results obtained from subgrade characterization testing (CBR, vane shear, light weight deflectometer, and repeated load triaxial tests) at the FAA NAPTF.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/9780415871990
• Supplemental Notes:
  • Abstract reprinted with permission of Taylor & Francis.
• Corporate Authors:

  CRC Press/Balkema

  P.O. Box 447
  2300 AK Leiden,   Netherlands 
• Authors:
  • Garg, Navneet
  • Larkin, A
  • Brar, H
• Conference:
  • Bearing Capacity of Roads, Railways and Airfields. 8th International Conference (BCR2A'09)
  • Location: Champaign IL, United States
  • Date: 2009-6-29 to 2009-7-2
• Publication Date: 2009

Language

• English

Media Info

• Media Type: Web
• Edition: e-book ISBN 9780203865286
• Features: Figures; Photos; References; Tables;
• Pagination: pp 57-64
• Monograph Title: Bearing Capacity of Roads, Railways and Airfields. Proceedings of the 8th International BCR2A'09 Conference

Subject/Index Terms

• TRT Terms: Airport runways; Base course (Pavements); California bearing ratio; Deflectometers; Dynamic modulus of elasticity; Load tests; Modulus of resilience; Pavement design; Shear strength; Subgrade (Pavements); Subgrade materials; Subsoil; Triaxial shear tests
• Uncontrolled Terms: Light weight deflectometers
• Subject Areas: Aviation; Geotechnology; Materials; Pavements; I22: Design of Pavements, Railways and Guideways; I23: Properties of Road Surfaces;

Filing Info

• Accession Number: 01342911
• Record Type: Publication
• ISBN: 9780415871990
• Files: TRIS
• Created Date: Jun 23 2011 9:07AM