Evaluation of Secondary Consolidation Settlement Associated with Embankment Construction for Fast-paced Transportation Projects in Utah

This report discusses the design and implementation of surcharging technology in terms of the required laboratory, field and engineering evaluations. It is hoped that such information will provide a more consistent and technically defensible rationale for deploying this technology on highway projects constructed atop soft soils. Surcharging or preloading of the earthen embankments and underlying compressible soils is the most commonly deployed strategy to reduce the magnitude of secondary compression. Surcharging or overconsolidating of the foundation soils can be used to reduce the post-construction secondary settlement. In the course of this research, twenty-two consolidation tests and eighty-eight time rate tests were performed on Pleistocene and recent fine-grained, cohesive, lacustrine deposits comprised of Lake Bonneville and more recent clays, most likely of Utah Lake origin located along the Wasatch Front in Utah. Prior to analyzing the data, the test results were screened using the sample quality designation (SQD). Plots of the adjusted amount of surcharge (AAOS) were plotted versus the normalized rate of secondary settlement (Cₐ’/Cₐ) and compared with the research performed by Ng (1998). The data from this thesis plots higher than that reported by Ng (1998). This higher trend agrees better with the long-term settlement performance monitoring data obtained from the I-15 Reconstruction Project in Salt Lake County, Utah. Data from the time rate tests were used to determine the Cₐ/compression ratio (CR) ratio, giving a mean value of Cₐ/CR = 0.0442. This value compared favorably with the research performed by Ng (1998), which had a value of Cₐ/CR = 0.0433. Also provided with this report is a recommended method for designing surcharge fills considering post-construction (i.e., secondary compression) settlement.


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Appendices; Figures; Photos; References; Tables;
  • Pagination: 512p

Subject/Index Terms

Filing Info

  • Accession Number: 01703110
  • Record Type: Publication
  • Report/Paper Numbers: UT-17.22, MPC 20-422
  • Contract Numbers: 12-9310
  • Created Date: Apr 26 2019 4:58PM