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43 rd ANNUAL FHWA MIDWEST GEOTECHNICAL CONFERENCE Bloomington, MINNESOTA, OCTOBER 1-3, 2014

43 rd ANNUAL FHWA MIDWEST GEOTECHNICAL CONFERENCE Bloomington, MINNESOTA, OCTOBER 1-3, 2014 State of Practices in Databases for Deep Foundations Load Tests Dr . Naser Abu-Hejleh, FHWA Resource Center Dr. Murad Abu- Farsak , Louisiana State University

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43 rd ANNUAL FHWA MIDWEST GEOTECHNICAL CONFERENCE Bloomington, MINNESOTA, OCTOBER 1-3, 2014

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  1. 43rd ANNUAL FHWA MIDWEST GEOTECHNICAL CONFERENCE • Bloomington, MINNESOTA, OCTOBER 1-3, 2014 State of Practices in Databases for Deep Foundations Load Tests • Dr. Naser Abu-Hejleh, FHWA Resource Center • Dr. Murad Abu-Farsak, Louisiana State University • Dr. Muhannad T. Suleiman, Lehigh University • Dr. Ching Tsai, Louisiana DOT .

  2. Presentation Goals Help State DOTs and their researchers/consultants to: • Use foundation load test databases • Benefit from existing foundation load test databases • Develop quality foundation load test databases More accurate and economical foundations geotechnical design

  3. Presentation Outline • Applications of foundation load test databases • Contents and use of: • FHWA Deep Foundation Load test Database • Other Deep Foundation Load Test Databases • Recommendations

  4. Types of Methods to Determine Foundations Geotechnical Resistance & Displacement • Full-scale static load test: most accuratemethod • Simple prediction methods (analytical expression): • Static analysis (α- and β- methods) • Soil/rock design properties (e.g., Rn= 2.5Abqu) • Dynamic analysis (dynamic load test; formula) • Driving records and hammer/soil information

  5. Load Test: Direct Measurements of Foundations Resistance/Displacements • Load test data can be used to develop more accurate/economical simple design methods

  6. How Foundation Load Test Data Can Be Used? • In the individualprojects they are used in to: • Optimize and/or verify the geotechnical design • Above and in the future to improve the simple geotechnical design methods. Needs: • Quality and complete data • Document the data (databases) Minimal extra efforts compared to the benefits!

  7. Foundations Load Test Database = Quality and Complete Data at Load Test Sites • Instrumented and proof Load test: • Procedure, direction & results (load-settlement curve) • Test foundation: type, layout, dimensions, construction, quality control • Soil/rock around the test foundation: • Design properties and the procedure to obtain them.

  8. Analysis of Load Test Databases For a group of test foundations, evaluate & compare: • Measuredresistance/displacement from load test • Predictedresistance/displacement from the simple design methods that will be evaluated. • Similar design and construction conditions for test and production foundations

  9. Applications of Foundation Load Test Databases By Designers:perform more accurate and economical design for production foundations in their projects

  10. Applications of Foundation Load Test Databases By Researchers:reliability calibration ofvarious(AASHTO, local, new) design methods: • Develop resistance factors • Identify/develop more accurate and economical: • Simple design methods • Testing methods to determine soil/rock properties • Methods for construction and quality control

  11. Future:Reliability-Based Foundation Geotechnical Design Methods This requires databases that include: • Quality and complete load test records • Statistically adequate to cover the common design and construction conditions in the US • Local databases are needed: • Accounts for specific design/construction conditions (more economical/accurate) • For methods not calibrated in AASHTO

  12. FHWA Deep Foundation Load Test Database (DFLTD) • Most comprehensive and largest database • 1307 load tests collected during 1985-2003 • Load transfer results for 21 test foundations • Used to develop other databases (discussed later) • Limitations: Missing and limited information • Distribution: contact FHWA (Dr. Naser Abu-Hejleh)

  13. FHWA DFLTD Information Location by States Subsurface Investigation

  14. FHWA DFLTD Information Pile Types Load Test

  15. FHWA DFLTD Information

  16. Other Deep Foundation Databases • PD/LT2000 (NCHRP Report 507, 2004 ) • AASHTO’s LRFD resistance factors () • Washington dynamic formula •  for drilled shafts (Ohio, 2012) • New Mexico (2012) • 24 drilled shaft load tests in granular soils • Resistance factors () for side resistance methods

  17. Deep Foundation Databases • PSU for Driven Piles (Oregon, 2010). • Identified quality data from DFLTD and applicable to Oregon practices • = 0.5 for wave equation analysis at EOD/BOR •  for different combinations of pile and soil types • California • Has a large number of load tests, archived in the web • On-going research study

  18. Deep Foundation Databases Florida DOT (FDOT): • Long history in development of databases • Deep Foundation Database • 627 load tests in Access database • Online database (100 load tests) • Local load test data • FDOT for driven piles and drilled shafts

  19. Deep Foundation Databases • International Database (Long, 2009) • Illinois: • Evaluation of various static/dynamic analysis methods • Identified/developed the best methods • Updated Illinois DOT design specifications • Wisconsin: Evaluation of 5 dynamic analysis methods and identified the best method

  20. Deep Foundation Databases • Pilot & DSHAFT Iowa online databases (2010-2011) • Local data • Driven piles (275) and drilled shafts (38) •  for driven piles: • Larger than AASHTO • Smaller than with calibration by fitting to ASD

  21. Deep Foundation Databases • Louisiana Load Tests (2008, 2012) • Driven piles (53) and drilled shafts (26) • Local load tests •  larger than AASHTO • Calibrate design methods not used in AASHTO

  22. Recommendations 1. Develop a national protocol to obtain and report quality and complete new data at load test sites: • Consistent procedure to obtain data: • Follow AASHTO/FHWA procedures • Consider local and new/better procedures • Report consistent data usingsimilar: • “Foundation Load Test Record Form” • Guide: describe the data and the procedure to obtain them

  23. Recommendations • Identify and compile existing quality load test data that were not documented 3. Deploy quality format and facilitate distribution • Consistent format with the national protocol • Flexibility to update, expand, modify, and access • Appealing user friendly interface to filter, sort, query, and generate the needed information. • Long-term management and maintenance • Online databases

  24. Recommendations 4. Develop quality and complete: • Local databases by states • Using their data and data of others appropriate to their design/construction conditions • Regional databases • Of states with similar design/construction conditions • National databases: • Bank for other states!! \

  25. Recommendations- Implementation Collaboration between Public and Private Highway Engineering Agencies

  26. Questions? Dr. Naser Abu-Hejleh, P.E. FHWA Resource Center naser.abu-hejleh@dot.gov; (708) 283-3550 • Will e-mail you: • FHWA Deep Foundation Load Test Database (DFLTD) • 2010 NHI Manual: “Implementation of LRFD Geotechnical Design for Bridge Foundations” • Relevant Papers • 2013 FHWA Report: “Implementation of AASHTO LRFD Design Specification for Driven Piles.” 

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