Volumetric change of silts following cyclic loading.

Details

• Creators:
  Baxter, Christopher D.P. ; Trautmann, Jan ; Taylor, Oliver-Denzil S.
• Corporate Creators:
  University of Rhode Island. Dept. of Ocean/Civil and Environmental Engineering
• Subject/TRT Terms:
  • Silts
  • Pile driving
  • Ground settlement
  • Repeated loads
  • S waves
  • Pore pressure
  • Literature reviews
  • Volume changes
  • State of the practice
• Publication/ Report Number:
  URITC FY08-09
• Resource Type:
  Tech Report
• Geographical Coverage:
  Rhode Island
• Corporate Publisher:
  University of Rhode Island. Transportation Center
• NTL Classification:
  NTL-HIGHWAY/ROAD TRANSPORTATION-Soils and Geology
• Abstract:
  Estimating the settlement of adjacent structures during pile installation in silts is a challenging problem for ; practicing engineers. The current state-of-practice relies primarily on local case studies and monitoring efforts, such as ; inclinometers and site surveys, where adjacent structures are in relatively close proximity to pile driving activity. Few ; predictive models exist to aid engineers, and those that do exist are limited to relatively “clean” sands and are rarely used ; in practice. A very important aspect of pile driving are the shear waves that will be generated causing localized regions of ; increased pore pressures resulting in significant reduction of soil strength and stiffness. Unfortunately, current practice ; does not provide an engineer with any quantifiable means to estimate how these shear waves would affect the local soil ; behavior. ; The objective of this study was to perform a detailed review of the literature regarding pile driving-induced ; settlements and to develop a laboratory testing program to quantify the relationship between cyclic loading, generation of ; pore pressures, and the resulting volume changes in silts.In the first part of the present work a review of case studies and a ; summary of settlement prediction methods are presented and the most important facts concerning those are highlighted. ; The second part focuses on a series of cyclic triaxial tests carried out to evaluate volumetric change caused by pore ; pressure dissipation of silt samples following cyclic loading. It was found that the greater the pore pressure ratio ; generated during cyclic loading, the greater the volume changes of the silt sample resulting from pore pressure ; dissipation. Cyclic loading and drainage caused a maximum of 5% volumetric strain in the silt samples, compared to less ; than 1% for sands in comparable studies. The measured increase in volumetric strain was small up to a pore pressure ratio ; of 0.6. The results of this research work supply important information on the behavior of volume changes of silt cyclically ; loaded and provide a sound basis for future settlement predictions of silt due to dynamic loading.
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• Format:
  PDF
• Funding:
  URI 0001851
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/26218/dot_26218_DS1.pdf
• File Type:
  [PDF - 2.05 MB]
• Collection(s):
  University Transportation Centers ; US Transportation Collection
• Main Document Checksum:
  urn:sha-512:7c634f92fc30e171ec8f4e109e83e980d5c1af6ff426f604f39e7426df8bdc89d909f8b99682913f07d0f26d0f3f44e8e96d74ed1574389f05de1cf64d4e26f3