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'�rFRNATto��v RECEIVED
May 10; 2017
Phoenix Realty Homes JAN $ 0 2018
Attn: Alan Tarpell
1760 N. Jog Road, Suite 140 ST, 6u�1��94lrlky, Permitting ,
West Palm Beach, Florida 33411 J,
Site: Proposed Three-Story Residence
8016 S Ocean Dr. (Lot 15 Diamond Sands)
St. Lucie County,.Florida
GFA Project#17-4162.00
Dear Mr. Tarpell:
GFA International, Inc. (GFA) has completed the subsurface exploration and geotechnical
engineering evaluation for the above-referenced project in accordance with the geotechnical
and engineering service agreement for this project. The scope of services was completed in
accordance with our Geotechnical Engineering Proposal (17-4162.00), planned in conjunction
with and authorized by you.
EXECUTIVE SUMMARY
The purpose of our subsurface exploration was to classify the nature of the subsurface soils and
general geomorphic conditions and evaluate their impact upon the proposed construction. This
report contains the results of our subsurface exploration at the site and our engineering
interpretations of these, with respect to the project characteristics described to us including
providing recommendations for site preparation and the design of the foundation system.
Based on the Paving, Grading and Drainage plan prepared by LBFH dated 03-25-04
(reproduced as the Test Location Plan) and conversations with the client, the project consists of
constructing a three-level residence. GFA has performed soil borings and provided geotechnical
recommendations for the site and numerous lots at the subdivision. The residential structure (or
portion thereof) will be located east of the Coastal Construction Control Line (CCCL) and
therefore a pile supported foundation is required. The residence will be elevated above a lower
level garage that may have walls and ground floor slab of frangible breakaway design. At the
time of this report, the site grade was about even with the adjacent road and GFA estimates
(based on nearby lot elevations and associated topographic data) that the site is generally at
about +7 feet NAVD and 0 to 1 foot of fill will be required to achieve final grade.We assume the
residence will have typical construction, and be supported on columns terminating on pile caps
slightly below the ground floor elevation.
The recommendations provided herein are based upon the above considerations. If the project
description has been revised, please inform GFA International so that we may review our
recommendations with respect to any modifications.
521 NW Enterprise Drive - Port St.Lucie,Florida 34986 - (772)924.3575 - (772)924.3580(fax) - www.teamgfa.com
OFFICES THROUGHOUT FLORIDA
Proposed Three-Story Residence Geotechnical Report
8016 S Ocean Dr. (Lot 15 Diamond Sands), St. Lucie County, FL May 10, 2017
GFA Project No. 17-4162.00 Page 2 of 12
A total of one (1) standard penetration test (SPT) boring to a depth of approximately forty-five
(45) feet below ground surface (BGS) was completed for this study. GFA has performed soil
borings and provided geotechnical recommendations for the site and numerous lots at the
subdivision.
At the time of this report, the site grade was about even with the adjacent road and GFA
estimates (based on nearby lot elevations and associated topographic data) that the site is
generally at about +7 feet NAVD. The subsurface soil conditions encountered at the boring
location generally consist of:
➢ +7 to +3 feet NAVD: Loose dense sand (SP)
➢ +3 to-6 feet NAVD: Medium dense sand (SP)
➢ -6 to-23 feet NAVD: Dense sand (SP)
➢ -23 to-38 feet NAVD: Loose/soft sand with silt layers (SP,SM,ML)
Please refer to Appendix D-.Record of Test Borings for a detailed account of each boring.
For pile supported structures, GFA recommends using a deep foundation system consisting of
augered cast-in-place (ACIP) piles. Based on our analysis, GFA has estimated that a 14-inch-
diameter ACIP pile installed to an elevation of -23 feet NAVD (about 30 feet below existing
grade) can provide a maximum allowable axial compressive capacity of 35 tons and a maximum
tension capacity of 11 tons, and a 16-inch-diameter ACIP pile installed to an elevation of -23
feet NAVD (about 30 feet below existing grade) can provide a maximum allowable axial
compressive capacity of 40 tons and a maximum tension capacity of 13 tons.
For the ground supported frangible walls and floor slabs, an allowable bearing capacity of 2,500
psf may be used for shallow footing foundation design.
The subgrade soils should be improved with compaction from the stripped grade prior to
constructing the foundation pads and footing excavations. The top 2 feet below stripped grade
should be compacted to a minimum of 95% density prior to placing fill to achieve final grade.
Fill (including stemwall backfill) should be placed in 12-inch lifts and compacted to achieve a
minimum 95% density. After excavation for footings, the subgrade to a depth of 2 feet below
bottom of footings should be compacted to achieve a minimum 95% density.
Scour elevations used in pile calculations are those provided by the Florida DEP for coastal
construction, but may not be adequate for actual scour elevations in hurricane(s) event(s) that
exceed the DEP assumptions and cause lower scour elevations. Therefore, GFA analysis is
limited to that provided by the DEP scour elevation, and scour analysis is not included in our
scope of work.
Proposed Three-Story Residence Geotechnical Report
8016 S Ocean Dr. (Lot 15 Diamond Sands), St. Lucie County, FL May 10, 2017
GFA Project No. 17-4162.00 Page 3 of 12
We appreciate the opportunity to be of service to you on this project and look forward to a
continued association. Please do not hesitate to contact us if you have any questions or
comments,•or ifve.rrtay further assist you as your plans proceed.
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GFA ° iat�'drl��jff n+r�
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Proposed Three-Story Residence Geotechnical Report
8016 S Ocean Dr. (Lot 15 Diamond Sands), St Lucie County, FL May 10, 2017
GFA Project No. 17-4162.00 Page 4 of 12
TABLE OF CONTENTS
1.0 INTRODUCTION .................................................................................................................5
1.1 Scope of Services............................................................................................................5
1.2 Project Description...........................................................................................................5
2.0 OBSERVATIONS.................................................................................................................6
2.1 Site Inspection .................................................................................................................6
2.2 Field Exploration..............................................................................................................6
2.3 Laboratory Analysis..........................................................................................................6
2.4 Geomorphic Conditions....................................................................................................6
2.5 Hydrogeological Conditions..............................................................................................7
3.0 ENGINEERING EVALUATION AND RECOMMENDATIONS ..............................................7
3.1 Foundation Recommendations- General.........................................................................7
3.2 Pile Foundation................................................................................................................8
3.3 Pile Installation.................................................................................................................9
3.4 Vibration Monitoring ........................................................................................................9
3.5 Design of Footings (Ground Level Frangible Walls).......................................................10
3.6 Ground Floor Slab (Frangible)......................... ..............10
.................................................
3.7 Site Preparation.............................................................................................................10
4.0 REPORT LIMITATIONS.....................................................................................................12
5.0 BASIS FOR RECOMMENDATIONS..................................................................................12
Appendix A-Vicinity Map
Appendix B-Test Location Plan
Appendix C- Notes Related to Borings
Appendix D- Record of Test Borings
Appendix E- Discussion of Soil Groups
Proposed Three-Story Residence Geotechnical Report
8016 S Ocean Dr. (Lot 15 Diamond Sands), St. Lucie County, FL May 10, 2017
GFA Project No. 17-4162.00 Page 6 of 12
2.0 OBSERVATIONS
2.1 Site Inspection
The project site was generally grassy with some trees and shrubs. The grade at the site was
estimated to be even with the adjacent road at the time of drilling. The Atlantic Ocean bordered
the east side of the property.
2.2 Field Exploration
A total of one (1) standard penetration test (SPT) boring to a depth of approximately forty-five
(45) feet below ground surface (BGS) was completed for this study. The location of the boring
performed is illustrated in Appendix B: "Test Location Plan". The Standard Penetration Test
(SPT) method was used as the investigative tools within the boring. SPT tests were performed
in substantial accordance with ASTM Procedure D-1586, "Penetration Test and Split-Barrel
Sampling of Soils". The SPT test procedure consists of driving a 1.4-inch I.D. split-tube sampler
into the soil profile using a 140-pound hammer falling 30 inches. The number of blows per foot,
for the second and third 6-inch increment, is an indication of soil strength.
The soil samples recovered from the soil boring were visually classified and their stratification is
illustrated in Appendix D: 'Record of Test Borings". It should be noted that soil conditions might
vary between the strata interfaces, which are shown. The soil boring data reflect information
from a specific test location only. Site specific survey staking for the test locations was not
provided for our field exploration. The indicated depth and location of each test was
approximated based upon existing grade and estimated distances and relationships to obvious
landmarks. The boring depths were confined to the zone of soil likely to be stressed by the
proposed construction and knowledge of vicinity soils.
2.3 Laboratory Analysis
Soil samples recovered from our field exploration were returned to our laboratory where they
were visually examined in general accordance with ASTM D-2488. Samples were evaluated to
obtain an accurate understanding of the soil properties and site geomorphic conditions. After a
thorough visual examination of the recovered site soils, no laboratory testing was deemed
necessary. Bag samples of the soil encountered during our field exploration will be held in our
laboratory for your inspection for 30 days and then discarded unless we are notified otherwise in
writing.
The recovered samples were not examined, either visually or analytically, for chemical
composition or environmental hazards. GFA would be pleased to perform these services for an
additional fee, if required.
2.4 Geomorphic Conditions
The geology of the site as mapped on the USDA Soil Survey website consists of Canaveral fine
sand, 0 to 5 percent slopes (8). These are sandy soils and organic soils are not indicated. It
should be,noted that the Soil Survey generally extends to a maximum depth of 80 inches
(approximately 63/feet)below ground surface and is not indicative of deeper soil conditions.
Jimmy Rouan
Crystal Pools
Director of Sales_
(772)567-306.7 x261 n r%
(772)47372311 Mobile
jimmyrCrysC$lpaplsire.csn ,-
4650 N.US1
Vero Beach,Fl.S2967
Have a great day!
2
Proposed Three-Story Residence Geotechnicai Report
8016 S Ocean Dr. (Lot 15 Diamond Sands), St. Lucie County, FL May 10, 2017
GFA Project No. 17-4162.00 Page 7 of 12
Boring logs derived from our field exploration are presented in Appendix D: "Record of Test
Borings". The boring logs depict the observed soils in graphic detail. The Standard Penetration
Test borings indicate the penetration resistance, or,N-values, during the drilling and sampling
activities. The classifications and descriptions shown-on the logs are generally based upon
visual characterizations of the recovered soil samples. All soil samples reviewed have been
depicted and classified in general accordance with the Unified Soil Classification System,
modified as necessary to describe typical Florida conditions. See Appendix E: "Discussion of
Soil Groups", for a detailed description of various soil groups.
At the time of this report, the site grade was about even with the adjacent road and GFA
estimates (based on nearby lot elevations and associated topographic data) that the site is
generally at about +7 feet NAVD. The subsurface soil conditions encountered at the boring
location generally,consist of:
➢ +71to +3 feet NAVD: Loose dense sand (SP)
➢ +3.to-6 feet NAVD: Medium dense sand (SP)
➢ -6 to-23 feet NAVD: Dense sand (SP)
➢ -23 to-38 feet NAVD: Loose/soft sand with silt layers (SP,SM,ML)
Please refer to Appendix D- Record of Test Borings for a detailed account of each boring.
2.5 Hydrogeological Conditions .
On the dates of our field exploration, the groundwater table was encountered at a depths of
from approximately 6.3 feet below the existing ground surface. The groundwater table will
fluctuate seasonally depending upon local rainfall and other site specific and/or local influences
including the water level in the nearby Atlantic Ocean with tidal influences. Brief ponding of
stormwater may occur across the site after heavy rains.
No additional investigation was included in our scope of work in relation to the wet seasonal
high groundwater table or any existing well fields in the vicinity. Well fields may influence water
table levels and cause significant fluctuations. If a more comprehensive water table analysis is
necessary, please contact our office for additional guidance.
3.0 ENGINEERING EVALUATION AND RECOMMENDATIONS
3.1 Foundation Recommendations - General
The residential structure (or portion thereof) will be located east of the Coastal Construction
Control Line(CCCL) and therefore a pile supported foundation is required. Frangible ground
floor slabs and ground level walls may be pile supported or supported on footings in accordance
with rules and regulations (to be determined by others).
i
kris wetherall
SUBMITTED ED TO: 321-0078
CRYSTAL POOLS OF INDIAN RIVER STREET i 325 96 SA
4684 N,US1 CITY,STATE,ZIP
VERO BEACH FL. 32967
772-567-3067 PHONE)
FAX 770-5961
STATE.CPC#1457120 DATE: 1-12-18
L CENSED AND INSURED JOB NAME:
JOB SITE: STONE13141GIDIGE
SUBDIVISION:
Install.wetedge pi so blue instead of florida gem standard finish.
WE PROPOSE HEREBY TO FURNISH MA RIAL AND LABOR-CO PLETE
IN ACCORDANCE WITH ABOVE SPECIE ATIONS,FOR THE SUM O
PAYMENT TO BE MADE AS FOLL S:' Add to contract
ALL MATERIAL IS GUARANTEED TO B AS SPECIFIED.ALL WORK TO BE COMPLETED IN A SUBSTA AL WORKMANLIKE MANNER ACCORDING TO.SPECIFICATIONS
SUBMITTED,PER STANDARD PRACTICES.ANYALTERATION OR DEVIATION FROM ABOVE SPECIFICA ONS INVOLVING EXTRA COSTS WILL BE EXECUTED ONLY
UPON WRITTEN ORDERS,AND WILL BECOME AN EXTRA CHARGE OVER AND ABOVE THE ESTIMATE. AGREEMENTS CONTINGENT UPON STRIKES,ACCIDENTS
OR DELAYS BEYOND OUR CONTROL.OWNER TO CARRY FIRE,TORNADO,AND OTHER NECESSARY IN RANCE.OUR WORKERS ARE FULLY COVERED BY
WORKER'S COMPENESATION INSURANCE.
AUTHORIZED SIGNATURE:
NOTE:THIS PROPOSAL MA4 BE WITHDRAWN BY US IF NOT
ACCEPTED WITHIN 30''DAYS
DEPOSITS ARE NON-REFUNDABLE
ACCEPTANCE OF PROPOSAL
THE ABOVE PRICES,SPECIFICATIONS,AND CONDITIONS ARE DATE OF ACCEPTANCE:
SATISFACTORY AND ARE HEREBY ACCEPTED.YOU ARE
AUTHORIZED TO DO THE WORK AS SPECIFIED.PAYMENT WILL SIGNATURE:
BE MADE AS OUTLINED ABOVE.
Proposed Three-Story Residence Geotechnical Report
8016 S Ocean Dr. (Lot 15 Diamond Sands), St Lucie County, FL- -May 10, 2017
GFA Project No. 17-4162.00 Page 5 of 12
1.0 INTRODUCTION
1.1 Scope of Services
The objective of our geotechnical services was to collect subsurface data for the subject project,
summarize the test results, and discuss any apparent site conditions that. may' have
geotechnical significance for building construction. The following scope of services are provided
within this report:
1. Prepare records of the soil boring logs depicting the' subsurface'soil conditions encountered
during our field exploration.
2. Conduct a review of each soil sample obtained during our field exploration for classification
and additional testing if necessary.
3. Analyze the existing soil conditions found during our exploration with respect to foundation
support for the proposed structure.
4. Provide recommendations,with respect to foundation support of the structure, including
allowable soil-bearing capacity, bearing elevations, and foundation design parameters.
5. Provide criteria and site preparation procedures to prepare the site for the proposed
construction.
1.2 Project Description
Based on the Paving, Grading and Drainage plan prepared by LBFH dated 03-25-04
(reproduced as the Test Location Plan)and conversations with the client, the project consists of
constructing a three-level residence. GFA has performed soil borings and provided geotechnical
recommendations for the site and numerous lots at the subdivision. The residential structure (or
portion thereof) will be located east of the Coastal Construction Control Line (CCCL) and
therefore a pile supported foundation is required. The residence will be elevated above a lower
level garage that may have walls and ground floor slab. of frangible breakaway design. At the
time of this report, the site grade was about even with the adjacent road and GFA estimates
(based on nearby lot elevations and associated topographic data) that the site is generally at
about+7 feet NAVD and 0 to 1 foot of fill will be required to achieve final grade.We assume the
residence will have typical construction, and be supported on columns terminating on pile caps
slightly below the ground floor elevation.
We have not received any information regarding structural loads. For the foundation
recommendations presented in this report we assumed the maximum column load will be 80
kips and the maximum wall loading will be 4 kips per linear foot.
The recommendations provided herein are based upon the above considerations. If the project
description has been revised, please inform GFA International so that we may review our
recommendations with respect to any modifications.
Jimmy Rouan
From: MaryAnne Spence[MalryryAnne@croomconstruction.com]
Sent: Friday, January 12, 2018 2:19 PM
To: 'jimmyr@crystalpoolsirc.com'
Subject: Difazio-Your NOC
Attachments: DiFazio-Crystal Pools INOC.pdf
You gave man NOC for ow your
to' sign:'
e
I gave it to you in our papers but her . it is. again.
LX]
www.croomconstruction.com<http:/./www.croomconstruction.com>
1
Proposed Three-Story Residence Geotechnicat Report
8016 S Ocean Dr. (Lot 15 Diamond Sands); St. Lucie County, FL May 10, 2017
GFA ProjedfNo. 17-4162.00 Page 8 of 12
3.2 Pile Foundation
The following is design parameters GFA used for pile recommendations:
➢ For CCCL construction,the FDEP has established a 100-year storm elevation (bottom of
lowest structural member) :of +17.0 or +17.9 feet NGVD (depends on location) for
structures within St. Lucie County.
➢ For CCCL construction, the FDEP has established a 100-year storm erosion elevation
(design scour elevation)of+2.7 feet NGVD for all of St. Lucie County.
➢ A loss of soil support between the bottom of lowest structural member and design scour
elevation (+2.7 feet NGVD) was included in compressive, tensile, and lateral pile
capacity analyses.
➢ We assume the residence will have typical construction, and be supported on columns
terminating on pile caps slightly below the ground floor elevation. We assume that fill will
be placed to achieve final (or near final) grade before installing the pile foundations, and
top of piles (bottom of pile caps)would be about+8 feet NGVD/+6.5 feet NAVD.
At this time, GFA recommends the deep foundation to consist of augered cast-in-place piles
(ACIP). Additional lateral capacity may be attained by utilizing inclined piles. We assumed that
the piles will have a minimum of 1% steel reinforcement for the analyses. ACIP pile installation
procedures should be performed in accordance with the guidelines presented in the latest
edition of the Deep Foundations Institute's Augered Cast-In-Place Pile Manual. The lateral
capacity and pile top deflection were calculated using the commercially available L-pile 4.0
software. A summary of pile capacities for a 14-inch diameter ACIP piles is presented in the
following table.
r
Pile Recommendations For All Pile Su ported Structures
Maximum
Nominal ENGVD
Recommended Pile Pile Pile Lateral
Pile n Pile Tip Pile Lengths Compression Tension Capacity Recommended
Diameter * Elevation (ft)*** Capacity Capacity (Tons)" Grout Strength
0.5 Tons
-23 feet NAVD (Free Head)
(-21.5 feet 1.25 Tons
14" Unknown NGVD) Unknown 35 Tons 11 Tons Fixed Head 5000 psi
0.75 Tons
-23 feet NAVD (Free Head)
(-21.5 feet 1.5 Tons
16" Unknown NGVD) Unknown 40 Tons 13 Tons Fixed Head 5000 psi
*Pile top elevation assumed above+2.7 feet NGVD (1.2 feet NAVD)for analyses.
**For calculated pile top deflection of%2 inches at top of pile elevation.
***From existing grade would be about 30 ft.long.
GFA assumed that the piles will have a minimum of 1% steel reinforcement for the analyses.
Augercast piles should be reinforced , over their entire length for tension capacity. The
reinforcement shall be as designed by the Structural Engineer.
If piles of lesser or greater capacities than those mentioned in the table above are required,
GFA would be pleased to provide further recommendations upon request.
Proposed Three-Story Residence Geotechnical Report
8016 S Ocean Dr. (Lot 15 Diamond Sands), St. Lucie County, FL May 10, 2017
GFA Project No. 17-4162.00 Page 9 of 12
The following additional notes are applicable to the pile design:
• Structural stresses in the piles may impose a more severe limitation on the
design capacity; therefore, we recommend the allowable stresses be verified for
the selected pile section.
• The pile reinforcement is sufficiently embedded in the pile cap so as to afford a
fixed end connection if required.
3.3 Pile Installation
Pile design and installation shall be in accordance with the applicable sections of the Florida
Building Code and other applicable federal, state and local requirements. In addition, piles
should be installed in accordance with the following:
1. Pile Length: The proposed 14-inch-diameter piles should be installed as determined by
the inspecting Geotechnical Engineer.
2. Spacing - Piles installed in groups should be spaced at a center-to-center distance of not
less than 3 pile diameters.
3. Plan Location - The center of the top of any pile at cut-off should be displaced laterally
no more than 3 inches from the position shown on the plans. This applies to both single
piles and piles installed in groups.
4. Vertical Alignment - The vertical alignment of the piling should not deviate from the
plumb by more than 1/4 inch per foot of length.
5. Reinforcing Cage Positioning - The top of the reinforcing cages installed in the piling
should not be more than 6 inches above and no more than 3 inches below the positions
shown in the plans. The reinforcing cages should be positioned concentrically within the
grouted pile shaft. The grout cover over longitudinal reinforcing bars should not be less
than 3 inches. Reinforcing centralizers shall be placed at maximum spacing of 15 feet at
the lower portion of the pile and at 5 feet from the cage's top.
6. Adjacent Piles - A minimum time period of 12 hours should be specified for the
installation of piles located within 5 feet, center-to-center, of each other.
7. Grout Factor-The minimum acceptable grout factor (i.e. actual grout•volume divided by
theoretical grout volume)should be 1.1.
3.4 Vibration Monitoring
The proposed construction may be within close proximity to residential structures and roadways
that maybe susceptible to damage from vibration generated at the site. We recommend that
during all aspects of construction, the bordering landmarks be monitored using a seismograph
to determine the extent of vibration absorption that these features will be subject to. The
Proposed Three-Story Residence Geotechnical Report
8016 S Ocean Dr. (Lot 15 Diamond Sands), St. Lucie County, FL May 10, 2017
GFA Project No. 17-4162.00 Page 10 of 12
seismograph used to monitor at this site should have the capability to measure ground velocities
along vertical, transverse, and longitudinal axes. The project structural engineer should
establish allowable ground velocities that the bordering facilities can safely withstand without
any damage.
3.5 Design of Footings (Ground Level Frangible Walls)
Footings may be designed using an allowable soil bearing pressure of 2,500 psf. Shallow
foundations should be embedded a minimum of 12 inches below final grade. This embedment
shall be measured from the lowest adjacent grade. Isolated column footings should be at least
24 inches in width and continuous strip footings should have a width of at least 18 inches
regardless of contact pressure.
Once site preparation has been performed in accordance with the recommendations described
in this report, the soil should readily support the proposed structure resting on a shallow
foundation system. Settlements have been projected to be less than 1-inch total and Y2-inch
differential. All footings and columns should be structurally separated from the floor slab, as
they will be loaded differently and at different times, unless a monolithic mat foundation is
designed.
3.6 Ground Floor Slab (Frangible)
The ground floor slabs may be supported directly on the existing grade or on granular fill
following the foundation site preparation and fill placement procedures outlined in this report.
For purposes of design, a coefficient of subgrade modulus 160 pounds per cubic inch may be
used. The ground floor slab should be structurally separated from all walls and columns to
allow for differential vertical movement.
Water vapor is likely to rise through the granular fill and condense beneath the base of the floor
slab. If moisture entry into the floor slab is not desirable, an impermeable membrane should be
installed at the slab bottom -subgrade interface.
3.7 Site Preparation
GFA recommends the following compaction requirements for this project:
➢ Proof Roll......................................................................95% of a Modified Proctor
➢ Building Pad Fill ............................................................95% of a Modified Proctor
➢ Footings........................................................................95% of a Modified Proctor
The compaction percentages presented above are based upon the maximum dry density as
determined by a "modified proctor' test (ASTM D-1557). All density tests should be
performed to a depth of 2 feet below stripped surface and 2 feet below bottom of
footings. All density tests should be performed using the nuclear method (ASTM D-2922), the
sand cone method (ASTM D-1556), or Hand Cone Penetrometer(HCP)tests.
Our recommendations for preparation of the site are presented below. This approach to
improving and maintaining the site soils has been found to be successful on projects with similar
soil conditions.
Proposed Three-Story Residence Geotechnical Report
8016 S Ocean Dr. (Lot 15 Diamond Sands), St. Lucie County, FL May 10, 2017
GFA Project No. 17-4162.00 Page 11 of 12
1. Initial site preparation should consist of performing stripping (removing surface vegetation,
near surface roots, and other deleterious matter) and clearing operations. This should be
done within, and to a distance of five (5) feet beyond, the perimeter of the proposed building
footprint (including exterior isolated columns). Foundations and any below grade remains of
any structures that are within the footprint of the new construction should be removed, and
utility lines should be removed or properly abandoned so as to not affect structures. If the
demolished residence had a pile foundation, GFA must be notified as the recommendations
may change.
2. Following site stripping and prior the placement of any fill, areas of surficial sand (not
exposed limestone) should be.compacted ("proof rolled') and tested. We recommend using
a steel drum vibratory roller with sufficient static weight and vibratory impact energy to
achieve the required. compaction. Density tests should be performed on the proof rolled
surface at a frequency of not less than one test per 2,500 square feet, or a minimum of three
(3)tests,whichever is greater. Areas of exposed intact limestone shall be visually confirmed
by the project geotechnical engineer prior to fill placement, in lieu of proof rolling.
3. Fill material may then be placed in the building pad as required. The fill material should be
inorganic(classified as SP, SW, GP, GW, SP-SM, SW-SM, GW-GP, GP-GM) containing not
more than 5 percent (by weight) organic materials. Fill materials with silt/clay-size soil
fines in excess of 12% should not be used. Fill should be placed in lifts with a maximum
lift thickness not exceeding.12-inches. Each lift should be compacted and tested prior to the
placement of the next lift. Density tests should be performed within the fill at a frequency of
not less than one test per 2,500 square feet per lift in the building areas, or a minimum of
three (3)tests per lift, whichever is greater.
4. For any footings bearing on a limestone formation, the bottom of all footing excavation shall
be examined by the engineer / geologist or his representative to determine the condition of
the limestone. The limestone shall be probed for voids and loose pockets of sand. Such
areas shall be cleaned to depth of 3 times the greatest horizontal dimension and backfilled
with lean concrete.
5. For footings placed on structural fill or compacted native granular soils, the bottom of all
footings shall be tested for compaction and examined by the engineer / geologist or his
representative to determine if the soil is free of organic and/or deleterious material. Density
tests should be performed at a frequency of not less than one (1) density test per each
isolated column footing and one (1) test per each seventy five (75) lineal feet of wall
footings.
6. Upon completion of production pile installation and pile cap construction, the pile caps
should be backfilled in 6 to 8 inch thick lifts and compacted to at least 95% of the modified
Proctor maximum dry density(ASTM D 1557).
7. The contractor should take into account the final contours and grades as established by the
plan when executing his backfilling and compaction operations.
Proposed Three-Story Residence Geotechnical Report
8016 S Ocean Dr. (Lot 15 Diamond Sands), St. Lucie County, FL May 10, 2017
GFA Project No. 17-4162.00 Page 12 of 12
Using vibratory compaction equipment at this site may disturb adjacent structures. We
recommend that.you monitor nearby structures before and during proof-compaction operations.
A representative of GFA International can monitor the vibration disturbance of adjacent
structures. A proposal for vibration monitoring during compaction operations can be supplied
upon request.
4.0 REPORT LIMITATIONS
This consulting report has been prepared for the exclusive use of the current project owners and
other members of the design team for the Proposed Residence located at 8016 S Ocean Dr.
(Lot 15 Diamond Sands), St. Lucie County, Florida. This report has been prepared in
accordance with generally accepted local geotechnical engineering practices; no other warranty
is expressed or implied. The evaluation submitted in this report, is based in part upon the data
collected during a field exploration, however, the nature and extent of variations throughout the
subsurface profile may not become evident until the time of construction. If variations then
appear evident, it may be necessary to reevaluate information and professional opinions as
provided in this report. In the event changes are made in the nature, design, or locations of the
proposed structure, the evaluation and opinions contained in this report shall not be considered
valid, unless the changes are reviewed and conclusions modified or verified in writing by GFA
International.
Scour elevations used in pile calculations are those provided by the Florida DEP for coastal
construction, but may not be adequate for actual scour elevations in hurricane(s) event(s) that
exceed the DEP assumptions and cause lower scour elevations. Therefore, GFA analysis is
limited to that provided by the DEP scour elevation, and scour analysis is not included in our
scope of work.
5..0. BASIS FOR RECOMMENDATIONS
The analysis and recommendations submitted in this report are based on the data obtained
from the tests performed at the locations indicated on the attached figure in Appendix B. This
report does not reflect any variations; which may occur between borings. While the borings are
representative of the subsurface conditions at their respective locations and for their vertical
reaches, local variations characteristic of the subsurface soils of the region are anticipated and
may be encountered. The delineation between soil types shown on the soil logs is approximate
and the description represents our interpretation of the subsurface conditions at the designated
boring locations on the particular date drilled.
Any third party reliance of our geotechnical report or parts thereof is strictly prohibited without
the expressed written consent of GFA International. The applicable SPT methodology (ASTM
D-1586), CPT methodology (ASTM D-3441), and Auger Boring methodology (ASTM D-1452)
used in performing our borings and sounding, and for determining penetration and cone
resistance is specific to the sampling tools utilized and does not reflect the ease or difficulty to
advance other tools or materials.
Appendix A - Vicinity Map
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Appendix B - Test Location Plan
Test Location Plan: 8 1 0 6 S Ocean Dr (Lot15 Diamond Sands), St. Lucie County, FL
Michelle Franklin, CFA- Saint Lucie County Properly Appraiser
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May 10,2017 1:1.128
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000P(t13lt2GJ?Wit Leek Cwly►Itpel4/gPf3lset.AYAJItt catlnee.
-�-Approximate Standard Penetration Test(SPT) Location
Appendix C - Notes Related to Borings
NOTES RELATED TO
RECORDS OF TEST BORING AND
GENERALIZED SUBSURFACE PROFILE
1. Groundwater level was encountered and recorded(if shown) following the completion of the soil test boring on
the date indicated.Fluctuations in groundwater levels are common;consult report text for a discussion.
2. The boring location was identified in the field by offsetting from existing reference marks and using a cloth tape
and survey wheel.
3.. The borehole was backfilled to site grade following boring completion,and patched with asphalt cold patch mix
when pavement was encountered.
4. The Record of Test Boring represents our interpretation of field conditions based on engineering examination of
the soil samples.
5. The Record of Test Boring is subject to the limitations,conclusions and recommendations presented in the Report
text.
6. "Field Test Data"shown on the Record of Test Boring indicated as 11/6 refers to the Standard Penetration Test
(SPT)and means 11 hammer blows drove the sampler 6 inches.SPT uses a 140-pound hammer falling 30 inches.
7. The N-value from the SPT is the sum of the hammer blows required to drive the sampler the second and third 6-
inch increments.
8. The soil/rock strata interfaces shown on the Records of Test Boring are approximate and may vary from those
shown.The soil/rock conditions shown on the Records of Test Boring refer to conditions at the specific location
tested;soil/rock conditions may vary between test locations.
9. Relative density for sands/gravels and consistency for silts/clays are described as follows:
SPT CPT SANDS/GRAVELS SPT CPT SILTS/CLAYS
BLOWS/FOOT KG/CM RELATIVE DENSITY BLOWS/FOOT KG/CM CONSISTENCY
04 0-16 Very loose 0-1 0-3 Very soft
5-10 17-40 Loose 2-4 4-6 Soft
11-30 41-120 Medium Dense 5-8 7-12 Finn
31-50 121-200 Dense 9-15 13-25 Stiff
50+ over 200 Very Dense 16-30 25-50 Very stiff
>30 >50 Hard
10. Grain size descriptions areas follows:
NAME SIZE LIMITS
Boulder 12 Inches or more
Cobbles 3 to 12 Inches
Coarse Gravel %to 3 Inches
Fine Gravel No.4 sieve to Y4 inch
Coarse Sand No. 10 to No.4 sieve
Medium Sand No.40 to No. 10 sieve
Fine Sand No.200 to No.40 sieve
Fines Smaller than No.200 sieve
11. Definitions related to adjectives used in soil/rock descriptions:
PROPORTION ADJECTIVE APPROXIMATE ROOT DIAMETER ADJECTIVE
<5% Trace Less than 1/32" Fine roots
5%to 12% Little 1/32"to''/<" Small roots
12%to 30% Some ''/a"to V Medium roots
30%to 50% And Greater than V Large roots
Organic Soils:Soils containing vegetable tissue in various stages of decomposition that has a fibrous to amorphous texture,
usually a dark brown to black color,and an organic odor.
Organic Content<25%:Slightly to Highly Organic;25%to 75%:Muck;>75%:Peat
Appendix D - Record of Test Borings
GFA INTERNATIONAL
521 N.W.ENTERPRISE DRIVE,PORT ST.LuclE,FLORIDA 34986
PHONE: (772) 924-3575 - FAx: (772) 924-3580
STANDARD PENETRATION TEST BORING(ASTM D-1586)
Client: Phoenix Realty Homes Project No.:17-4162.00
Lab No.:
Project: 8016 S Ocean Dr(Lot 15 Diamond Sands) Page: 1 of 1
St.Lucie County,Florida Date: 5/8/2017
Elevation: Existing Grade Drill Rig: CME45
Water Level:6.3 feet after 0 hours Drilling Fluid commenced at depth of 8 feet Field Party: PM/NM
TEST LOCATION: SPT- 1 N27.317960 W80.225670 Laboratory Tests
Depth Blows/ N Sample Layer: Passing Moisture Organic
(feet) 6 in. Value No. From/to USCS Description No.200 Content Content
1 0 6 SP Brown fine sand,trace shell
- -- 1 . .. ..4... 1
--- 2 . 3 .......
6
---- 4
3 ...........................
_ -- 6 10 2
q . 6 .......
5
--- 5 6
..........................
-- 5 11 3
6
7 6 10 SP Brown fine to medium sand
7 10
..........................
4
-- 8 11 ....................... ...
7
10
9 .....i.1........2i.... 5
- --10 14.
11 .......
12 ........ .......
13 ........ .......
-- IA
17 13%s- 15 SP Brown fine to medium sand,little shell
15
15
.....1-71 6
16 ........ .......
17 ........ .......
18 ........ .......
19 19 18%2-20 SP Brown fine to medium sand,little shell
_ 19
20 39 7
GFA INTERNATIONAL
521 N.W.ENTERPRISE DRIVE,PORT ST.LUCIE,FLORIDA 34986
PHONE: (772)924-3575 - FAx: (772) 924-3580
STANDARD PENETRATION TEST BORING(ASTM D-1586)
Client: Phoenix Realty Homes Project No.:17-4162.00
Lab No.:
Project: 8016 S Ocean Dr(Lot 15 Diamond Sands) Page: 2 of 3
St.Lucie County,Florida Date: 5/8/2017
Elevation: Existing Grade Drill Rig: CME45
Water Level:6.3 feet after 0 hours Drilling Fluid commenced at depth of 8 feet Field Party: PM/NM
TEST LOCATION: SPT- 1 N27.31796° W80.22567° Laboratory Tests
Depth Blows/ N Sample Layer: USCS Descrl tion Passing Moisture Organic
(feet) 6 in. Value No. From/to p no.200 Content Content
20 ----- ------
21 .......
22 ........ .......
23 ........ .......
----24
9 23'/z-25 SP Gray fine sand
...................
12
---25 16 28
26 ........ .......
27 ........ .......
28 ........ .......
---- 12 28%2-30 SP Gray fine sand,trace shell
29
15
30 ....22 37.... 9
31 ........ .......
32 ........ .......
33 ........ .......
34
WOH 33%z-35 SM,ML Gray fine sand and silt
WOH
35 WOH -W-0-H 10 WOH=Weight of Hamner
36 ........ .......
37 ........ .......
38 ........ .......
39 •• 4 38'h-40 SP Gray fine sand,trace silt and clay
......2
6 8 11
Appendix E - Discussion of Soil Groups
GFA INTERNATIONAL
521 N.W.ENTERPRISE DRIVE,PORT ST.LuclE,FLORIDA 34986
PHONE: (772)924-3575 - FAX: (772) 924-3580
STANDARD PENETRATION TEST BORING(ASTM D-1586)
Client: Phoenix Realty Homes Project No.:17-4162.00
Lab No.:
Project: 8016 S Ocean Dr(Lot 15 Diamond Sands) Page: 3 of 3
St.Lucie County,Florida Date: 5/8/2017
Elevation: Existing Grade Drill Rig: CME45
Water Level:6.3 feet after 0 hours Drilling Fluid commenced at depth of 8 feet Field Party: PM/NM
TEST LOCATION: SPT- 1 N27.31796° W80.22567° Laboratory Tests
Depth Blows/ N Sample Layer: Passing Moisture Organic
(feet) 6 in. Value No. From/to USCS Description No.200 Content Content
40 ------ ----
41 ........ .......
42 .......
43 ........ .......
44 4 43%2-45 SM,ML Gray fine sand and silt
...................
2
45 ......3 5..... 12
...........
Terminated boring at 45 feet
46 ........ .......
47 ........ .......
48 ........ .......
49 ........ .......
50 ........ .......
5 I ........ .......
52 ........ .......
53 ........ .......
54 ........ .......
55 ........ .......
56 ........ .......
57 ........ .......
58 ........ .......
59 ........ .......
DISCUSSION OF SOIL GROUPS
COARSE GRAINED SOILS
GW and SW GROUPS. These groups comprise well-graded gravelly and sandy
soils having little.or no plastic fines (less than percent passing the No. 200 sieve).
The presence of the fines must not noticeably change the strength characteristics
of the coarse-grained friction and must not interface with it's free-draining
characteristics.
GP and SP GROUPS. Poorly graded gravels and sands containing little of no
plastic fines (less than 5 percent passing the No. 200 sieve) are classed in GP
and SP groups. The materials may be called uniform gravels, uniform sands or
non-uniform mixtures of very coarse materials and very fine sand, with
intermediate sizes lacking (sometimes called skip-graded, gap graded or step-
graded). This last group often results from borrow pit excavation in which gravel
and sand layers are mixed.
GM and SM GROUPS. In general, the GM and SM groups comprise gravels or
sands with fines (more than 12 percent the No. 200 sieve) having low or no
plasticity. The plasticity index and liquid limit of soils in the group should plot
below the "A" line on the plasticity chart. The gradation of the material is not
considered significant and both well and poorly graded materials are included.
GC and SC GROUPS. In general, the GC and SC groups comprise gravelly or
sandy soils with fines (more than 12 percent passing the No, 200 sieve) which
have a fairly high plasticity. The liquid limit and plasticity index should plat above
the "A" line on the plasticity chart.
FINE GRAINED SOILS
ML and MH GROUPS. In these groups, the symbol M has been used to
designate predominantly silty material. The symbols L and H represent low and
high liquid limits, respectively, and an arbitrary dividing line between the two set
at a liquid limit of 50. The soils in the ML and MH groups are sandy silts, clayey
silts or inorganic silts with relatively low plasticity. Also included are loose type
soils and rock flours.
CL and CH GROUPS. In these groups the symbol C stands for clay, with L and
H denoting low or high liquid limits, with the dividing line again set at a liquid of
50. The soils are primarily organic clays. Low plasticity clays are classified as
CL and are usually lean.clays, sandy clays or silty clays. The medium and high
plasticity clays are classified as CH. These include the fat clays, gumbo clays
and some volcanic clays.
OL and OH GROUPS. The soil in the OL and OH groups are characterized by
the presence of organic odor or color, hence the symbol O. Organic silts and
clays are classified in these groups. The materials have a plasticity range that
corresponds with the ML and MH groups.
HIGHLY ORGANIC SOILS
The highly organic soils are usually very soft and compressible and have
undesirable construction characteristics. Particles of leaves, grasses, branches,
or other fibrous vegetable matter are common components of these soils. They
are not subdivided and are classified into one group with the symbol PT. Peat
humus and swamp soils with a highly organic texture are typical soils of the
group.