Control of Embankment Settlement Field Verification on PCPT Prediction Methods

Piezocone penetration tests (PCPT) have been widely used by geotechnical engineers for subsurface investigation and evaluation of different soil properties such as strength and deformation characteristics of the soil. This report focuses on the verification of the PCPT settlement prediction methods for estimating the magnitude and time-rate of consolidation settlement of embankments over fine-grained soils. The settlement prediction methods involve the interpretation of piezocone penetration soundings and dissipation tests to determine the consolidation parameters, which include constrained modulus (M), overconsolidation ratio (OCR), and the horizontal and vertical coefficients of consolidation (ch ,cv). This Louisiana Transportation Research Center (LTRC) research team selected two case study sites, Juban Road Interchange Bridge at I-12 and Bayou Courtableau Bridge, to verify the PCPT predicted magnitude and time-rate of settlement. The embankments at each site were instrumented with horizontal inclinometers and vertical extensometers to monitor/measure their settlement with time. Both conventional one-dimensional consolidation tests and PCPT tests were performed to determine the consolidation parameters needed to calculate the magnitude and time-rate of consolidation settlements. The predicted magnitude and time-rate of consolidation settlements estimated using the laboratory one-dimensional consolidation tests and the PCPT tests were compared with field measurements. The results of this study showed that the piezocone penetration and dissipation data can reasonably estimate the magnitude and rate of consolidation settlement within the same range of accuracy as of the laboratory calculation. Friendly, visual basic software (Louisiana Embankment Settlement Prediction Program from PCPT, LESPP-PCPT) was also developed to calculate the magnitude and time-rate of consolidation settlements for symmetrical and unsymmetrical embankments utilizing the PCPT and dissipation tests for use by geotechnical engineers.

• Record URL:
  • http://www.ltrc.lsu.edu/pdf/2011/fr_476.pdf
• 
• Record URL:
  • https://rosap.ntl.bts.gov/view/dot/23069
• Corporate Authors:

  Louisiana State University, Baton Rouge

  Department of Civil and Environmental Engineering
  Baton Rouge, LA  United States  70803

  Louisiana Department of Transportation and Development

  1201 Capitol Access Road, P.O. Box 94245
  Baton Rouge, LA  United States  70804-9245

  Louisiana Transportation Research Center

  4101 Gourrier Avenue
  Baton Rouge, LA  United States  70808

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Abu-Farsakh, Murad Y
  • Yu, Xinbao
  • Gautreau, Gavin
• Publication Date: 2011-7

Language

• English

Media Info

• Media Type: Web
• Edition: Final Report
• Features: Figures; References;
• Pagination: 81p

Subject/Index Terms

• TRT Terms: Consolidation; Dissipation; Embankments; Field tests; Geotechnical engineering; Ground settlement
• Uncontrolled Terms: Piezocone penetration tests
• Subject Areas: Geotechnology; Highways; I42: Soil Mechanics;

Filing Info

• Accession Number: 01354134
• Record Type: Publication
• Report/Paper Numbers: FHWA/LA.10/476
• Files: NTL, TRIS, USDOT, STATEDOT
• Created Date: Oct 19 2011 12:53PM