Improving Agreement Between Static Method and Dynamic Formula for Driven Cast-In-Place Piles in Wisconsin

This study focuses on comparing the capacities and lengths of piling necessary as determined with a static method and with a dynamic formula. Pile capacities and their required lengths are determined two ways: 1) using a design and computed method, such as the static method (Nordlund/Thurman/Tomlinson) identified in the Wisconsin Bridge Manual, and 2) using as-driven information, such as the Wisconsin-modified Engineering News Formula, the modified-Gates method. A collection of 182 cases was used to compare predictions made with the static method with prediction made using the Federal Highway Administration (FHWA)-modified Gates driving formula. The most effective factors influencing the agreement between predictions made by DRIVEN and FHWA-Gates were the effective stress at the tip of the pile, the friction angle for coarse-grained soils, and whether load was carried in side resistance or end bearing. Correction factors are developed to correct the static method for overburden stress at the tip of the pile. Furthermore, conditional limits are suggested for the friction angle for coarse-grained soils. Improvements were attained in the agreement for pile length required for many of the cases, however, in about 10 percent of the cases, the prediction of length of piling was not as accurate and the overall coefficient of variation increased. However, predictions of capacity at the depth driven in the field was significantly improved. Coefficients of variation for the agreement between methods improved to 0.28 from the original 0.98.

• Record URL:
  http://wisdotresearch.wi.gov/wp-content/uploads/WisDOT-WHRP-project-0092-10-09-final-report.pdf
• 
• Summary URL:
  http://wisdotresearch.wi.gov/wp-content/uploads/WisDOT-WHRP-project-0092-10-09-brief.pdf
• Corporate Authors:

  University of Illinois, Urbana-Champaign

  Department of Civil and Environmental Engineering
  205 North Mathews Avenue
  Urbana, IL  United States  61801-2352

  Wisconsin Department of Transportation

  Division of Business Services, Research Coordination Section
  4802 Sheboygan Avenue
  Madison, WI  United States  53707

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Long, James H
• Publication Date: 2013-6

Language

• English

Media Info

• Media Type: Digital/other
• Edition: Final Report
• Features: Appendices; Figures; References; Tables;
• Pagination: 114p

Subject/Index Terms

• TRT Terms: Bearing capacity; Cast in place structures; Dynamic models; Formulas; Length; Pile driving; Piles (Supports)
• Uncontrolled Terms: Driven piles; Static models
• Geographic Terms: Wisconsin
• Subject Areas: Bridges and other structures; Design; Highways; I24: Design of Bridges and Retaining Walls;

Filing Info

• Accession Number: 01497505
• Record Type: Publication
• Report/Paper Numbers: WHRP 0092-10-09
• Contract Numbers: WisDOT SPR# 0092-10-09
• Files: TRIS, ATRI, USDOT, STATEDOT
• Created Date: Nov 5 2013 8:14PM