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1 43 rd ANNUAL FHWA MIDWEST GEOTECHNICAL CONFERENCE Bloomington, MINNESOTA, OCTOBER 1-3, 2014 State of Practices in Databases for Deep Foundations Load.

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Presentation on theme: "1 43 rd ANNUAL FHWA MIDWEST GEOTECHNICAL CONFERENCE Bloomington, MINNESOTA, OCTOBER 1-3, 2014 State of Practices in Databases for Deep Foundations Load."— Presentation transcript:

1 1 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 Dr. Muhannad T. Suleiman, Lehigh University Dr. Ching Tsai, Louisiana DOT.

2 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 3 Presentation Outline 1.Applications of foundation load test databases 2.Contents and use of:  FHWA Deep Foundation Load test Database  Other Deep Foundation Load Test Databases 3.Recommendations

4 4 Types of Methods to Determine Foundations Geotechnical Resistance & Displacement 1.Full-scale static load test: most accurate method 2.Simple prediction methods (analytical expression):  Static analysis (α- and β- methods)  Soil/rock design properties (e.g., R n = 2.5A b q u )  Dynamic analysis (dynamic load test; formula)  Driving records and hammer/soil information

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

6 6 How Foundation Load Test Data Can Be Used? 1.In the individual projects they are used in to:  Optimize and/or verify the geotechnical design 2.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 7  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. Foundations Load Test Database = Quality and Complete Data at Load Test Sites

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

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

10 10 Applications of Foundation Load Test Databases By Researchers: reliability calibration of various (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 11 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 Future: Reliability-Based Foundation Geotechnical Design Methods

12 12 FHWA Deep Foundation Load Test Database (DFLTD)  Most comprehensive and largest database  1307 load tests collected during  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 13 FHWA DFLTD Information State# of Load Tests State# of Load Tests State# of Load Tests California327Louisiana245Florida163 Mississippi98Texas37New York36 Arizona35Pennsylvania24Hawaii23 South Carolina19Nevada18Colorado11 Massachusetts11Washington10New Mexico 8 Boring DataLab DataSPTCPTPMT CohesiveNon-CohesiveVariable Rock s IGM Location by States Subsurface Investigation

14 14 FHWA DFLTD Information Pile Types Drilled Shafts Pile: Square Concrete Pile: Round Concrete Pile: Steel H- pile Pile: Timber Pile: Step Tapered Open Pipe Pile Screw Pile (3), Micropile (4), Monotube (18), Auger cast (9), Composite (13), Franki (10) Type of Loads CompressionTensionLateral Type of Load Tests StandardQuickOsterbergStatnamic Other Criteria CyclicTo FailureCAPWAP Load Test

15 15 FHWA DFLTD Information Construction Methods for Drilled Shafts Drilled and Grouted DryWet with Bentonite Wet with Casing Left Wet with Casing Withdrawn With Polymer Slurry Wet Water only Cast- in- Place N/A Construction Methods for Driven Piles Impact Driven Mandrel Driven Concrete Filled VibratedScrew Pile JackedVibrated and Driven N/A

16 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 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 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 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 20 Deep Foundation Databases  Pilot & DSHAFT Iowa online databases ( )  Local data  Driven piles (275) and drilled shafts (38)   for driven piles:  Larger than AASHTO  Smaller than with calibration by fitting to ASD

21 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 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 using similar:  “Foundation Load Test Record Form”  Guide: describe the data and the procedure to obtain them

23 23 Recommendations 2.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 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 25 Recommendations- Implementation Collaboration between Public and Private Highway Engineering Agencies

26 26 Questions? Will 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.” Dr. Naser Abu-Hejleh, P.E. FHWA Resource Center (708)


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