• DFI Europe
  • DFI India
  • DFI Trust

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

David Graham, P.E.
Dan Brown and Associates PC

David Graham, P.E., is a senior engineer with Dan Brown and Associates in Chattanooga, Tennessee. He has over 14 years of experience in the geotechnical engineering and construction industry. He has consulted on deep foundation design, load testing and construction for many major bridges throughout the U.S., including several Mississippi River crossings and the Gordie Howe International Bridge currently under construction between Detroit, Michigan, and Windsor, Ontario. Graham is a licensed professional engineer in nine states and the District of Columbia. He is the lead author of eight peer-reviewed technical papers. An active member of ASCE and DFI Graham holds B.S. and M.S. degrees in civil engineering from Auburn University.


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.

Guide to Support Fluids for Deep Foundations (1st Edition)

EFFC-DFI task force outlined the state of the art of support fluid practice to improve existing design, testing and practices for deep foundation elements – bored piles (drilled shafts), barrettes (LBEs) and diaphragm wall panels.

CSL Task Force

Supporting Testing and Evaluation Committee review of existing cross hole sonic logging rating criteria and proposing improvements for potential future incorporation in codes and specifications.

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.


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)