Numerical analysis of dense narrow backfills for increasing lateral passive resistance.

Details

• Creators:
  Rollins, Kyle L. ; Nasr, Mo'oud ; Gerber, Travis M.
• Corporate Creators:
  Brigham Young University. Department of Civil and Environmental Engineering
• Corporate Contributors:
  United States. Federal Highway Administration
• Subject/TRT Terms:
  • Bridges
  • Bridge abutments
  • Sheet piling
  • Lateral supports
  • Loads
  • Bridges--Utah--Abutments
  • Piling (Civil engineering)
  • Lateral loads
• Resource Type:
  Tech Report
• Geographical Coverage:
  Utah
• Edition:
  Final.
• Corporate Publisher:
  Utah. Dept. of Transportation. Research Division
• Abstract:
  Previously, full-scale lateral load tests conducted on pile caps with different aspect ratios showed that placement ; of a narrow, dense backfill zone against the cap could substantially increase the passive resistance. The objective ; of this study is to develop design equations to predict the increased passive resistance for these limited width ; backfills for both 2D and 3D conditions. For this purpose, the finite element program, PLAXIS 2D was used to ; investigate the 2D or plane strain passive resistance. To validate the procedure, numerical results were calibrated ; against analytical results obtained from PYCAP and ABUTMENT. The analytical models were additionally ; validated by comparison with measured ultimate passive resistances. The calibrated model was then used to ; simulate the passive behavior of limited width gravel backfills. Parametric studies were also executed to ; evaluate the influence of a range of selected design parameters, related to the pile cap geometry and backfill soil ; type, on the passive resistance of limited width backfills. Numerical results indicated that significant increases in ; passive resistance could be expected for long abutment walls where end effects are less pronounced and the ; geometry is closer to a plane strain condition. Based on results obtained from the parametric studies, a design ; method was developed for predicting the ultimate passive resistance of limited width backfills, for both plane ; strain and 3D geometries. Comparisons between measured and numerical results indicated that using the Brinch- ; Hansen 3D correction factor, R3D, as a multiplier to the plane strain resistances, will provide a conservative ; estimate of the actual 3D passive response of a pile cap with a limited width backfill.
  More +
• Format:
  PDF
• Funding:
  06 9148
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/18446/dot_18446_DS1.pdf
• File Type:
  [PDF - 3.91 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:b4620572e8f98d49120e61cc72367e6a1b6487e3fb8befebca2fff98f196e0a2