Investigation of Aggregate Particle and Geogrid Aperture Sizes for Mechanical Stabilization Using Bender Element Shear Wave Transducers

This paper presents findings of a study focused on investigating geogrid lateral restraint mechanism and the associated mechanical stabilization with the use of bender element (BE) shear wave transducers, which can measure shear wave velocities in the vicinity of a geogrid to quantify the associated local stiffness enhancement. Three gradations of a pavement base course aggregate material were tested in repeated load triaxial tests; the gradations conformed to the upper bound, engineered mid-range, and lower bound of an agency gradation band. Two geogrids with different triangular aperture sizes were used to stabilize the specimens at mid-height, and three BE pairs were installed to measure shear wave velocities across the specimen. Results indicated that the specimen stiffening due to geogrid-aggregate interlocking could be successfully measured in certain matching combinations of the aggregate particle and geogrid aperture sizes studied. While the enhancement in resilient modulus was mainly due to aggregate properties, the increases in shear wave velocities with the use of geogrids, i.e., stiffening effect, was greatly dependent on both the aggregate and the geogrid aperture sizes. Considerable enhancements in stiffness due to geogrid-aggregate interlock can only be achieved when the aperture size and aggregate gradations – especially governed by a ratio of gravel to sand (G/S) size fractions for optimal packing and percentage of retained aggregates on certain sieve sizes, allowed for proper interlock with geogrid openings. A G/S ratio of 1.6 for the engineered mid-range gradation resulted in the highest geogrid-aggregate interlock when the smaller aperture size geogrid was used.

  • Supplemental Notes:
    • This paper was sponsored by TRB committee AFS70 Standing Committee on Geosynthetics.
  • Corporate Authors:

    Transportation Research Board

    ,    
  • Authors:
    • Kim, Joon Han
    • Byun, Yong-Hoon
    • Qamhia, Issam I A
    • Orihuela, Maximilian F
    • Tutumluer, Erol
    • Wayne, Mark
  • Conference:
  • Date: 2019

Language

  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; References; Tables;
  • Pagination: 7p

Subject/Index Terms

Filing Info

  • Accession Number: 01697285
  • Record Type: Publication
  • Report/Paper Numbers: 19-03810
  • Files: TRIS, TRB, ATRI
  • Created Date: Mar 1 2019 3:50PM