The document discusses recent trends in pile foundations, focusing on auger cast piles, particularly for projects with soft clay and high groundwater conditions in California. Nick Briffa of Delta Consultants presented various pile types, including auger cast and driven piles, and the importance of quality control for installation and load testing. Additionally, it covers the implementation of electronic monitoring for better project outcomes and highlights ongoing construction efforts using these technologies.

1. Recent Trends in Pile Foundations
Auger Cast Piles for
Low Noise / Low Vibration
Presenter: Nick Briffa, PE
Group Delta Consultants
Presented to:
ASCE Orange County Geo-Institute

2. Driven Piles

3. Auger Cast – Continuous Flight Auger
(CFA)
• Continuous Hollow
Screw Auger
• Genrates spoils
• Designed like CIDH
• No displacement
• Not common in Calif

4. Need for Auger Cast Piles
• Soft Clay Site
• High Groundwater
• Surcharge improvement not always possible
• Sound restrictions for driven piles
• Environmental restrictions for drilled piles
• Contaminated Groundwater/soil (no cuttings)

5. Auger Displacement Pile (ADP)
• Solid lead with
Displacement Tip
• Generates little spoils
• Designed like Driven
Pile
• Displacement
• Most common in Calif
• Morris-Shea, Condon-
Johnson, Malcolm,
Berkel

6. Auger Cast Pile Overview

7. Goal of Previous Test Programs
by Group Delta
• Test Program for Agency Acceptance
• Replacement for Driven 14” Concrete Piles
• 180-200 Kip Design Loads
• 70-100 Kip Liquefaction Down-drag loads
• 500-600 Kip Ultimate Capacity
• Over 50 Load Tests to date

8. Project Location
Largest Urban In-fill in US
$6 Billion development
Former Hughes Aircraft / Runway Facility

9. Playa Vista Geotechnical

10. AUGER CAST PRESSURE GROUTED
(closed system, continuous grout pressure)

11. QC - Installation
Record
• Improvement from standard
record
• Real-Time plots of torque, grout
pressure and grout take with
depth (not time)
• Field Verification of embedment
depth into target layer
• Torque in absolute Kip-ft

12. DeWaal Pile
• Open System
• Concrete
Gravity
• Conc Feed
Pressure by
tremmie head

13. QA/QC - Installation
Record
• “Open System” – top open to
gravity
• DeWaal Pile, Fundex
Inspector’s IPad Screen

14. Torque as a Target Indicator
• Absolute torque analogous to driving energy
• Dense Sand/Gravel indicated by 60 Ft-Kips
• Good correlation with CPT Qc
• Useful for Installation / End Bearing
Verification

15. Torque vs. Qc

16. Typical Compression Test Result

17. Typical Tension Test Result

18. Load Test – Creep Plot
• Modified ASTM Procedure
• Held at Design load until less than 0.005 inch/hr.
(ASTM is 0.01 inch/hr)

19. Long Term Test – 62 days
• Tested at Ultimate Load – 602 Kips.

20. Pile Exhumation
Initial Jack-out Pile Lifting after relief holes drilled

21. Exhumed Pile Examination

22. Exhumed Pile Details
Pile “Belly” – Soft Clay
Response
Pile “Wart”

23. Exhumed Pile Details
Pile “Swirl” –
Sensitive Clay Response
Pile “Neck” – low grout at
interval

24. Pile Tip – In Dense Gravel from 50 feet deep

25. Composite of Exhumed Pile

26. Pile Coring

27. ADP Conclusions
• Local Agency Acceptance (DSA, City)
• Torque good indicator of bearing (60 ft-kips) –
independent of auger type
• Electronic Monitoring improved QC and installation
verification – better than Gamma or HighStrain
• Monitored Grout increment should be no more than
2 feet
• Long Term Testing at ultimate load – long term creep
• Pile Exhumation verified monitoring and NDT

28. Alternate Application
Auger Cast Tangent Pile Walls

29. Current Pile Installs and Testing
Morris Shea DeWaal Piles
• 8,000 Piles since 2013
• 50-70 Feet Long
• 500-600 Kip Ult. Capacity
• 200 Kip Allowable Capacity
• Another 2000 for 2 projects
starts Nov 2015

30. Accepted Specs
for Buildings
Open Systems
(DeWall, Fundex)

31. Accepted Specs for
Buildings
Closed Grout
Systems
(APGD, Alpha)