Pile Design from Constructability Perspective

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1 Pile Design from Constructability Perspective Prestressed Concrete Piles in Coastal Georgia Presented by: Guoming Lin, Ph.D., G.E., D.GE Senior Principal / Senior Consultant Savannah, Georgia November 8, 2017

2 Outline Geology and Geotechnical Challenges Prestressed Concrete Piles in the Marl o o o Marl Formation Driveability and Driving Stresses Setup and Freeze Bearing Project Case History o Georgia Ports Container Berth 8 o o Truman Parkway Phase V Kinder Morgan Elba Island Terminal Summary & Conclusions

3 Savannah is in Coastal Plain Bedrock ft deep Three Geology Regions Blue Ridge Piedmont Coastal Plain

4 Soil Strata in Savannah

5 Silty Clay Sand Soft Clay Sand Marl Formation Soft Limestone Ref: Dames & Moore Talmadge Memorial Bridge Foundation Load Testing Report Sept 1985.

6 Soft Clay Floridian Limestone SPT Samples No Rock Core Sand Marl Formation 380 boring Soil Profile in upper 150 ft boring

every 5 years Building Constructed in 1975 Photo taken

8 Restroom for Hutchinson Island Golf Elba LNG Terminal Administration Building Supported on 6 piles A new step every 5 years Building Constructed in 1975 Photo taken in 2002 Ground settled >12 inches below pile-supported building

9 Soil Bearing Failure/Mud Wave Martin Marietta Aggregates / Marine Terminal Soils have consistency close to peanut butter

10 Outline Geology and Geotechnical Challenges Prestressed Concrete Piles in the Marl o o o Marl Formation Driveability and Driving Stresses Setup and Freeze Bearing Project Case History o Georgia Ports Container Berth 8 o o Truman Parkway Phase V Kinder Morgan Elba Island Terminal Summary & Conclusions

11 Prestressed concrete piles o Most commonly used along the Savannah River, Why? All piles are supported in the Marl o What is Marl? o Driveability and Driving Stresses o Setup and Freeze Bearing

12 PSC Piles Advantages Quality and reliability Local experience Corrosion resistant Cost: less expensive than steel H piles or pipe piles or drilled shafts Disadvantages Heavy to transport and handle Difficult to adjust length Cost: more expensive than timber pile, auger cast piles

13 Marl Loose or crumbling earthy deposit (as of sand, silt, or clay) that contains a substantial amount of calcium carbonate Miocene Formation-(5 to 23 million years ago) Olive green and gray color Marl

14 Marl, Origin and Characteristics The Cooper Marl* Skeletal remains of microscopic sea organisms Apparent over-consolidation due to cementation Uniform across the area Constant properties along depth SPT N=10 to 20, CPT tip q T ~50 tsf, V S ~1500 fps, S U ~4 ksf Difference of Savannah Marl Higher sand content Less calcareous Denser, SPT N=15 to 50, CPT tip q T ~50 to 100 tsf Pile driving difficulties: high blow counts and limited penetration High driving stresses and pile damage * ref: W.M. Camp (2002) Drilled and Driven Foundation Behavior in Calcareous Clay Proc. GeoCongress, Orlando, FL.

15 Marl, Excavated at SHEP Upper Water Intake Structure Rincon, Georgia Dense sandy silty clay can be excavated imperious

16 PSC Pile Behaviors in the Marl in Savannah High side frication capacities High pore pressure (CPT or pile driving) Setup/freeze effect Low compressibility/settlement Limited penetration High driving stresses (~hammer)

17 Outline Geology and Geotechnical Challenges Prestressed Concrete Piles in the Marl o o o Marl Formation Driveability and Driving Stresses Setup and Freeze Bearing Project Case History o Georgia Ports Container Berth 8 o o Truman Parkway Phase V Kinder Morgan Elba Island Terminal Summary & Conclusions

18 Three Case Histories GPA Container Berth 8 Kinder Morgan Elba Island Terminal Truman Parkway Phase V

19 Georgia Ports Garden City Terminal The longest contiguous berth in the US CB8 and 9

20 Dock: 1700 ft long Construction: barge mounted cranes Pile driving rig with swing lead Rigid steel framed templates

21 +15, Top of dock +10, Ground surface on land Subsurface Profile -16, Top of marl, undredged -48, Dredge depth Marl (silty sand clay, CL/CH) SPT N ~ 20 to 60

22 Pile Design Sizes: 20, 18, 16 square PSC Length: 60 to 98 ft Compression Capacities: 100 to 135 tons Ref: Lockwood Greene, GPA Container Berth 8 Dock, Aug 2003.

23 Pile Test Program 11 Indicator piles with PDA testing PDA testing: initial driving, 6 or 7 day restrike Static Load Testing: 2 Compression tests 1 Tension test

24 Pile Test Results-Driveability and Stresses Pile Hammer Model APE Rated Energy: kips-ft Ram Weight: 10.1 kips Pile cushion: 9 thick plywood Pile Casting Details 7000 psi concrete (actual>10,000 psi) 1000 psi effective prestressing Allowable Stress: compressive: 4.95 ksi Allowable Stress: tensile: 1.25 ksi Driving Resistances (blow counts): 10 to 45 bpf in the marl Occasionally > 50 bpf in dense layers All driven to tip elevations No pile damage observed Driving Stresses: Compressive: 2.4 to 4.7 ksi Tensile: 0.5 to 1.2 ksi Lower fuel setting to 2 to reduce driving stresses

25 Pile Test Results-Pile Capacities Max Load=360 tons Max deflection=0.40 inches Pile did not fail Max Load=440 tons Max deflection=0.41 inches Pile did not fail

26 Pile Test Results-Setup Effect and Capacity Increases Pile Capacity (tons) Test Pile End of Initial Drive 6D/7D Restrike Increase (tons) Percent IP4 (E-76) % IP5 (E-66) % IP6 (A-53) % IP7 (A-18) % IP8 (F-52) % IP9 (P-39.7) % IP10 (D-38) % IP11 (E-24) % IP12 (D-4) % IP13 (F.5-61) % IP14 (G-31) % Average %

27 Piles at CB8 Over 2,000 Piles Vertical and Horizontal Tolerance (rigid template) Only One Pile Damaged

28 Three Case Histories GPA Container Berth 8 Kinder Morgan Elba Island Terminal Truman Parkway Phase V

29 Truman Parkway V Marsh and Vernon River $72 million

30 Pile Casting Details-GDOT Standards 5000 psi concrete 734 psi prestressing Allowable Stress: compressive: 3.6 ksi Allowable Stress: tensile: 0.9 ksi 1782 piles 16 for end bents 18 for intermediate bents Design Load: 80 tons compression Pile Hammer Model ICE I-30 Rated Energy: 71.7 kips-ft Ram Weight: 6.6 kips Pile cushion: 8 thick plywood

31 BFI Report Min tip elevation=-12 to -16 m Estimated tip elevation=-17 m

32 Pile Testing and Driving Conditions Pile Testing: 17 probe piles along alignment GDOT does not require continuous monitoring End of Driving Blow Count as acceptance criteria Driving Resistances (blow counts): Mostly normal driving, achieved the required bearing Occasionally > 50 bpf in dense layers Min tip was adjusted to -13 meters for a few bends

33 Truman Parkway Phase V Pile Damage due to Tensile Driving Stress

34 PDA Testing and Driving Stresses PDA Testing: Bent 44, 18 Square, 73.8 ft long and tip m (-40 ft) CAPWAP Capacity 312 tons Driving Stresses: Max compression stress: 3.0 ksi Max tension stress: 0.7 ksi Pile driving procedures were adjusted to avoid driving damage

35 Three Case Histories GPA Container Berth 8 Kinder Morgan Elba Island Terminal Truman Parkway Phase V

36 Elba Island LNG Terminal 20,000 piles at the terminal >9,000 piles in current phase

37 Comparison of SPT, CPT and DMT Soundings SPT, CPT and DMT within 5 ft at Tank Center

38 SPT Comparison of SPT, CPT and DMT at Tank Center T5B5 T5C5 CPT DMT T5D1

39 Static Load Test-Setup

40 Static Test-Load Deflection Curves

41 Pile Instrumentation Plan Piles cast at Standard Concrete Products Savannah, Georgia

42 Static Test-Unit Side Friction

43 Pile Driving Stresses and Damage PDA Monitor

44 Pile Setup Effect (Strength Gain over Time) Test Pile No. Type Axial Load Test Results (tons) EOD 1 4DR 2 6D STN 3 TP1 18-in sq PPC D SLT 4 TP2 18-in sq PPC TP in dia. ICP TP4 18-in sq PPC Not Tested TP5 18-in sq PPC Axial Capacity Testing Program Summary. NOTES: EOD = End Of Driving (Dynamic) 4DR = 4 Day Restrike (Dynamic) 6D STN = 6 Day STATNAMIC test SLD capacity 12D SLT = 12 Day Static Load Test Average increases: 4 days=70%; 6 days=151%

45 Pile Driving Sequence Started with peripheral rings Over-densified sand layers Predrilling required to complete pile driving

46 Liquid Level = 113 ft Outer diameter = 258 ft Inner diameter = 252 ft 68 ft inch Square prestressed concrete piles

47 Elba Liquefaction Project (on-going) $2.4 billion project to convert the terminal into an LNG export facility 10 MMLS (movable modular liquefaction system) >9,000 prestressed concrete piles

48 Pile Test Program Prestressed concrete piles (18 and 14 square) Steel H piles Three types of auger cast piles: conventional auger, displacement and partial displacement piles

49 Very long case Difficult drilling

50 Speed! Speed! Speed!

51 Very large hammer High driving stress Green concrete No templates Alignment

52 Outline Geology and Geotechnical Challenges Prestressed Concrete Piles in the Marl o o o Marl Formation Driveability and Driving Stresses Setup and Freeze Bearing Project Case History o Georgia Ports Container Berth 8 o o Truman Parkway Phase V Kinder Morgan Elba Island Terminal Summary & Conclusions

53 Conclusions The Marl Formation is a reliable bearing stratum for piles. Marl has special characteristics that affect pile foundation design and construction. Prestressed concrete piles (PSC) have been the most popular foundation system along the Savannah River. Pile driving into the Savannah Marl can be difficult. Selection of pile hammer is critical for pile drivability. PSC piles are prone to damage by excessive driving stresses (compression and tension). Using higher strength concrete and prestressing than the current GDOT standards can help reduce the risk of pile damage. The setup effect for PSC piles in the marl is very significant and should be taken into account in the design and construction.

54 Acknowledgements Clients: Georgia Ports, Georgia DOT, Chatham County, Kinder Morgan Partners: CH2M-Hill, Moffatt Nichol, Jacobs, CB&I, IHI E&C Contractors: Orion Marine, Balfour Beatty, TIC, Bo-Mac, Cajun n Standard Concrete Products The Terracon Team (65+ strong in Savannah)

55 Thank You! Any Questions / Comments? Guoming Lin, Ph.D., G.E., D.GE Terracon Consultants Savannah, Georgia P: (912) E: glin@terracon.com

Evaluation of PDA Data to Identify Pile Issues Presented at Annual KC Specialty Seminar January 9, 2015

Evaluation of PDA Data to Identify Pile Issues Presented at Annual KC Specialty Seminar January 9, 2015 Presentation Topics Overview of PDA data collection Case histories for how PDA testing reduced the