Improvement of Driven Pile Installation and Design in Illinois: Phase 2

Long, James; Anderson, Andrew

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https://hdl.handle.net/2142/50310 Copy

Description

Title

Improvement of Driven Pile Installation and Design in Illinois: Phase 2

Author(s)

• Long, James
• Anderson, Andrew

Issue Date

2014-09

Keyword(s)

• piles
• driven piling
• pile capacity
• pile setup
• LRFD
• pile stresses
• driving stresses
• dynamic formula
• bearing capacity

Geographic Coverage

Illinois

Abstract

A dynamic load test program consisting of 38 sites and 111 piles with restrikes was conducted throughout Illinois to improve the Illinois Department of Transportation design of driven piling. Pile types included steel H-piles and closed-ended pipe (shell) piles. Piles were driven into all soil types including clay, silt, sand, shale, and limestone. Predictive methods for estimating pile capacity were investigated and include the K-IDOT (static) method, WSDOT (dynamic formula), WEAP, PDA, and CAPWAP. Pile capacities were taken as the capacity estimated using CAPWAP for beginning of restrike conditions. Piles were monitored during initial driving. Piles were re-driven several days later to assess the amount of setup to assess the effect of time, pile type and soil type. Restrikes were conducted typically between 3 and 15 days after initial driving. Modifying WSDOT to include effects of setup explicitly with specific equations for time-dependent setup was not any more precise than the original WSDOT formula with adjustments for pile type. Accordingly recommendations are made for adjusting WSDOT estimates based on whether the pile is an H-pile or a shell pile. Adjustments were made to the simplified stress formula (SSF) to refine predictions of stresses in driven H- and shell piles driven with diesel hammers. Resistance factors were determined using the First Order Second Moment method for the static method (K-IDOT) and the dynamic formula (WSDOT). Pile types included H-piles and shell piles for both end of driving conditions and for beginning of restrike. Resistance factors were also determined for WEAP and PDA. These resistance factors were determined using the CAPWAP (BOR) capacity as the static capacity for the pile, although it is preferable that the resistance factors be based on static load test. Accordingly, adjustments were made to the resistance factors accounting for the average agreement between capacity determined by CAPWAP(BOR) and capacity determined with a static load test.

Publisher

Illinois Center for Transportation/Illinois Department of Transportation

Series/Report Name or Number

Illinois Center for Transportation Series No. 14-021. Research Report No. FHWA-ICT-14-019

ISSN

0197-9191

Type of Resource

text

Language

en

Permalink

http://hdl.handle.net/2142/50310

Sponsor(s)/Grant Number(s)

Illinois Department of Transportation, R27-122

Copyright and License Information

No restrictions. This document is available to the public through the National Technical Information Service, Springfield, Virginia 22161.

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