HomeMy WebLinkAboutAPPROVED Halgas - Soil Reprot approved - 2.15.2022Addendum to Geotechnical Services 8112 South Ocean Drive, Jensen Beach, FL
13 January 2022 21 - 179
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3866 PROSPECT AVENUE SUITE 9 WEST PALM BEACH, FLORIDA 33404 (561) 881-1939
13 January 2022
Phoenix Custom Homes
1760 Jog Road, Suite 120
West Palm Beach, FL 33411
Subject: Addendum to Report of Geotechnical Services - 3-Level Custom Home
8112 South Ocean Boulevard, Diamond Sands Lot 24 Jensen Beach, Florida
Allterra Engineering & Testing respectfully submits this addendum to its report of
geotechnical services for the subject project dated 14 September 2021. This addendum
revises conclusions and recommendations about auger-cast pile capacity, load
deflection, and design. This addendum is Allterra’s instrument-of-service provided for
sole reliance and use by Phoenix Custom Homes. Third parties may read this report for
information purposes.
A digital copy of a memorandum dated September 16, 2021, and entitled Design Wave
Condition, 8112 S. Ocean Boulevard, Jensen Beach, St. Lucie County, Florida by
Isiminger & Stubbs Engineering was provided for Allterra’s refence in performing its
services. The memorandum presented information on design eroded-grade elevation,
breaking wave crest elevation, still water elevation, wave and debris impact forces on
square and round piles, and hydrodynamic wave forces
Allterra applied the memorandum’s information and conceptual subsurface profile from
the 14-September-2021 geotechnical services report to its design model. Allterra
estimated the following capacities for 14-inch and 16-inch auger-cast piles installed to
approximately 27 feet below surface grade (approximately 17 feet below scour grade).
Pile Diameter CULTIMATE CALLOWABLE CULT / CALLOW Uplift Resistance
14 inches 140 Kips 70 Kips 2.0 86 Kips
16 inches 160 Kips 80 Kips 2.0 99 Kips
Notes: CULTIMATE = ultimate compressive load capacity.
CALLOWABLE = allowable compressive load capacity.
CULT/CALLOW = CULTIMATE / CALLOWABLE
Uplift Resistance = (weight of pile + skin friction)/1.5.
Kips = 1000 pounds.
Considering the breaking wave crest elevation of +15.5 feet NAVD and FF elevation
from site plans, Allterra assumed a low structural floor beam at +18 feet NAVD
(approximately 19 feet above eroded grade). Model lateral displacements for fixed-toe
fixed-head piles installed to approximately 27 feet below surface grade (approximately
17 feet below scour grade) are summarized in following table:
Pile Diameter Single-Pile Displacement 4-Pile-Group Displacement
14 inches 3.1 inches 0.8 inch
16 inches 2.0 inches 0.5 inch
A L L T E R R A
E N G I N E E R I N G & T E S T I N G
DocuSign Envelope ID: 31221A37-B653-48BD-B89E-C494C0723342
Addendum to Geotechnical Services 8112 South Ocean Drive, Jensen Beach, FL
13 January 2022 21 - 179
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For auger-cast piles, Allterra recommends:
Pile Materials. Piles shall be formed with minimum 4000 PSI grout placed under
pressure as the auger is progressively withdrawn from the borehole. Piles (14-inch
diameter) shall be reinforced with five full-depth number-5 steel bars and number-3 ties
spaced not more than 16 inches on-center. Piles (16-inch diameter) shall be reinforced
with seven full-depth number-5 steel bars and number-3 ties spaced not more than 16
inches on-center. The structural engineer shall determine the number and distribution of
piles considering structural loads and geometry.
Pile Layout. The number and distribution of piles shall be determined by the structural
engineer considering project loads and geometry. Piles shall be spaced at-least 3
diameters center-to-center to avoid group effect on stress distribution in the bearing
stratum.
Pile-Installation Monitoring. Engage Allterra to monitor installation of piles. For
auger-cast piles, monitoring shall include:
1. Check pile layout for conformance to design foundation plan.
2. Observe field trial and calculate gout-pump factor.
3. Observe drilling of pile to verify target depths are achieved.
4. Observe grouting of pile bore to verify acceptable grout return.
5. Sample grout for compressive-strength testing.
6. Observe installation of reinforcing steel to verify full-depth penetration.
7. Test grout specimens to verify design compressive strength is achieved.
8. Calculate grout factors and summarize installation data for each pile.
9. Prepare report of work acceptance signed and sealed by Professional Engineer.
Please call the undersigned if one has questions about this report or needs other
services.
Yours truly,
Allterra Engineering & Testing
FBPE Registry No. 9139
Wendell Rodgers, PE
Principal Engineer
FL Lic. No. 55960
C: Rob Agsten, PE
This item has been digitally signed and sealed by
Wendell K. Rodgers, PE on the date adjacent to
the seal.
Printed copies of this document are not
considered signed and sealed and the signature
must be verified on electronic copies.
DocuSign Envelope ID: 31221A37-B653-48BD-B89E-C494C0723342