Prediction of the Ultimate Capacity of Driven Piles and Optimization of Design Parameters

This research endeavor encompasses the following objectives, as reiterated in the March 5, 2019 Memorandum between the author and the PhD Guidance Committee.

1. Evaluation of available methods for estimating the interpreted capacity of single driven piles from static load tests and address the research question as to which is the best method, especially for LDOEPs.

2. Evaluation of various available methods for calculating the nominal resistance of single driven piles against the pile load tests stored in the Warehouse; and selection of the best performing design method as the basis to propose an improved design method. In particular, you should address the research question of whether or not existing interpreted capacity methods from static load tests for piles wider than 36 inches are suitable for LDOEPs.

3. Address the long-standing research question of whether or not, and under what conditions does skin friction increase linearly with depth, using data in the Warehouse.

4. Employ the warehouse to provide recommendations for revised resistance factors for design.

5. Address the research question of whether or not soil plugging is affected by factors other than pile’s length to diameter ratio.

Members of the Ph.D. Guidance Committee:

• Magued Iskander, PhD, PE, Professor & Chair, Department of Civil and Urban Engineering, NYU

• Torsten Suel, PhD, Professor, Department of Computer Science and Engineering, NYU

• Muhannad Suleiman, PhD, Associate Professor, Department of Civil and Environmental Engineering, Lehigh University

• Antonio Marinucci, PhD, Adjunct Professor, Department of Civil and Urban Engineering, NYU

• Debra Laefer, PhD, Associate Professor, CUE & Professor of Practice, CUSP

Table of contents:

• 1. Introduction
• 2. Pile Load Test Data Warehouse
• 3. Algorithmic Implementation
• 4. Existing Interpreted Capacity Methods
  • 4.1. Description of Interpreted Capacity Methods
    • 4.1.1. Methods Based on Pile Properties and Shape of the Load Settlement Curve
      • 4.1.1.1. Davisson (1972)
      • 4.1.1.2. Davisson (AASHTO, Briaud)
      • 4.1.1.3. 5% Diameter
      • 4.1.1.4. 10% Diameter
      • 4.1.1.5. NYC Building Code Criterion
    • 4.1.2. Methods Based Only on the Shape of the Load Settlement Curve
      • 4.1.2.1. Hansen 80%
      • 4.1.2.2. Hansen 90%
      • 4.1.2.3. Chin-Kondner
      • 4.1.2.4. Decourt
      • 4.1.2.5. De Beer
      • 4.1.2.6. Maximum Curvature (Vesic)
      • 4.1.2.7. Butler-Hoy
      • 4.1.2.8. Fuller-Hoy
      • 4.1.2.9. Van Der Veen
  • 4.2. Evaluation of Interpreted Capacity Methods
    • 4.2.1. For Standard Width Piles
    • 4.2.2. For Large Diameter Open Ended Piles (LDOEP)
• 5. An Improved Interpreted Capacity Method
  • 5.1. For Standard Width Piles
  • 5.2. For Large Diameter Open Ended Piles (LDOEP)
• 6. Existing Nominal Capacity Methods
  • 6.1. Description of Nominal Capacity Methods
    • 6.1.1. Nordlund (1963)
    • 6.1.2. Tomlinson (1980)
    • 6.1.3. API RP2A (1993)
    • 6.1.4. Olson (1990)
    • 6.1.5. \(\beta\)-method (1993)
    • 6.1.6. Brown (2001)
    • 6.1.7. Eurocode 7
  • 6.2. Evaluation of Nominal Capacity Methods
    • 6.2.1. For Standard Width Piles
    • 6.2.2. For Large Diameter Open Ended Piles (LDOEP)
    • 6.2.3. Soil Arching
• 7. An Improved Nominal Capacity Method
  • 7.1. Based on a Mechanistic Approach
    • 7.1.1. For Side Resistance
    • 7.1.2. For End Bearing
  • 7.2. Based on Artificial Intelligence
• 8. Reliability Analysis for Resistance Factors
  • 8.1. Methodology
  • 8.2. Improved resistance factors for Nordlund 1963, Tomlinson 1980, \(\beta\)-method 1993, Eurocode 7
  • 8.3. New resistance factors for API RP2A 1993 and Brown 2001
• 9. Conclusion
  • 9.1. Summary
  • 9.2. Improved Methods
  • 9.3. Resistance Factors
  • 9.4. Recommendations for Future Research