Drilled Shaft
Advancing the state of the practice or state of the art in design, construction, and quality verification of drilled shaft foundation systems.
Committee Chair
Paul Axtell, P.E., D.GE
Dan Brown and Associates PC
paxtell@dba.world
Axtell is the Chief Operating Officer and a Senior Principal Engineer for Dan Brown and Associates in Overland Park, Kansas. In recent years, Paul has primarily focused on foundations for major bridge projects across the nation, delivered under a variety of project delivery methods. He is the Geotechnical Engineer of Record for eight Mississippi River Crossings and has acted as foundation design, construction, or load test consultant on several others.
Axtell holds a B.S. degree in civil engineering from the University of Missouri and a M.S. degree in engineering from the University of Texas with a geotechnical emphasis. He is registered as a professional engineer in 7 states and is a diplomate of the ASCE Academy of Geo-Professionals. Paul has over 20 years of experience in geotechnical and foundation engineering and has authored or co-authored more than 25 technical papers. Since 2013, he has served as chairman of the Deep Foundations Institute Drilled Shaft Committee. Axtell serves on the Board of Directors for the ASCE Academy of Geo-Professionals and was recently honored with admittance into the University of Missouri’s Civil Engineering Academy of Distinguished Alumni.
Upcoming Events
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48th Annual Conference on Deep Foundations
October 31 – November 3, 2023 – Seattle, Washington
Initiatives
Committee Research
DFI Committee Project Fund committee research projects
- Best Practices for Bored Pile/Drilled Shaft Design and Construction – International technical working group in North America and Europe defined best practices for design, construction, contracting, QC/QA and innovations. DFI Journal, Volume 10, Issue 2, December 2016.
- Literature review and development of online database of previous large scale pile experiments.
Shear Amplification in Rock Sockets Study – investigate shear amplification at soil-rock interface in rock socketed drilled shafts.
Tremie concrete pour simulation for 52 ft deep drilled shaft.
Colors represents the age of concrete. Stages simulate the lifted tremie pipe.
The oldest concrete is pushed to the top of shaft.
Guide to Tremie Concrete for Deep Foundations (2nd Edition)
EFFC-DFI task force developed guidance for characterization related to performance, mix design process, and methods used to test fresh concrete.
Side and Base Resistance Task Force
Studying the mechanisms of load transfer between side and base resistance in drilled shafts. Click below for consensus document on rock-socketed drilled shafts. Research on soil-supported drilled shafts continues.
Fundamentals
FHWA Geotechnical Engineering Circular No. 10 (FHWA-NHI-18-024) Drilled Shafts: Construction Procedures and LRFD Design Methods
FHWA Evaluation and Guidance Development for Post-Grouted Drilled Shafts for Highways
Final Report: Workshop on Quality Assurance for Post-Grouted Drilled Shafts
Manual for Non Destructive Testing and Evaluation of Drilled Shafts (#TM-NDT-1)
Drilled Shaft Inspector’s Manual (2nd edition) (#TM-DS-1)