Evaluation of the Base/Subgrade Soil under Repeated Loading : Phase I – Laboratory Testing and Numerical Modeling of Geogrid Reinforced Bases in Flexible Pavement

Details

• Creators:
  Abu-Farsakh, Murad ; Nazzal, Munir
• Corporate Creators:
  Louisiana State University (Baton Rouge, La.). Department of Civil and Environmental Engineering
• Subject/TRT Terms:
  • Subgrade (Pavements)
  • Base course (Pavements)
  • Flexible pavements
  • Deformation
  • Geogrids
  • Pavements--Subgrades
  • Pavements, Flexible
  • Surfaces, Deformation of
  • Deformations (Mechanics)
  • Geogrids
• Publication/ Report Number:
  FHWA/LA.09/450
• Resource Type:
  Tech Report
• Geographical Coverage:
  Louisiana
• OCLC Number:
  682160650
• Edition:
  Interim report; Aug. 2003-May 2007.
• Corporate Publisher:
  Louisiana Transportation Research Center
• NTL Classification:
  NTL-HIGHWAY/ROAD TRANSPORTATION-Materials ; NTL-HIGHWAY/ROAD TRANSPORTATION-Soils and Geology
• Abstract:
  This report documents the results of a study that was conducted to characterize the behavior of geogrid reinforced base ; course materials. The research was conducted through an experimental testing and numerical modeling programs. The ; experimental testing program included performing different laboratory tests to evaluate the effect of various factors on the ; performance geogrid reinforced base course materials. Finite element models were also developed to investigate the ; benefits of placing geogrids within the base course layer in a flexible pavement structure. The results of the experimental ; testing demonstrated that the inclusion of the geogrid reinforcement layer(s) improved the compressive strength and ; stiffness of base course materials under static loading. This improvement was more pronounced at higher strain levels. ; Furthermore, the results showed that the geogrid significantly reduced the base course material permanent deformation ; under cyclic loading, but it did not show appreciable effect on their resilient deformation. The finite modeling program ; showed that the geogrid reinforcement reduced the lateral, vertical, and shear strains within the base course and subgrade ; layers. Furthermore, the geogrid had an appreciable reduction in permanent deformation for pavement sections built on ; top of weak subgrade soils with medium to thin base layer thickness, with the thin base layer thickness showing greater ; values of improvement. However, negligible to modest reinforcement effect on permanent deformation was obtained for ; sections having a firm subgrade or thick base layer thickness. The geogrid reinforcement had modest to high values of ; improvement in fatigue life of pavement structure.
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• Format:
  PDF
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/18256/dot_18256_DS1.pdf
• File Type:
  [PDF - 1.45 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:04fc2677385b3e02a199a3b9b330ad4a1bca005ff1d2d7ef1012519af4238f18