HomeMy WebLinkAboutANALYSIS & RECOMENDATIONS-_____--mm 2 g 2018 -
i'cting Department
perm County,; FL
St, Lucie
Subject Property: Eberle Residence 65 Aqua Ra Dr, Jensen Beach FL
Project #:18-5521.00
Analysis and recommendation:
FIRST
SCANNED) PT I O N
BYENGINEERVNG. INSFFCTION. & CONSTRUCTION, LLC
May 8th, 2018
This letter is to address the field soil conditions for the above project. Review of documentation and analysis was
performed. The follow lists details of the project along with design parameters:
• Pool is to have a minimum depth of 42" with maz 60".
• Pool width is approximately 14ft
• Soil analysis indicates fine sand and rock to a depth of roughly 10ft.
• Below loft, soil was determined to have a minimum N-value of 10, with an average of 13.
%:
• Maximum settlement assumed to be "
Assuming worst case conditions, N-value equal to 10 consistently throughout, the allowable bearing pressure on the soil
was calculated to be roughly 2165psf, which is more than the minimum of 2000psf per design. Based on this allowable,
the use of piles does not appear to be necessary for the installation of this pool.
This calculated bearing pressure should be deemed only as a best guess as this analysis was based on soil information
from a sin le bore. Determination of soil conditions other than at this location is beyond the scope of this report.
Limitations
This report has been prepared in accordance with generally accepted professional engineering practice, based on review of
the provided documents and/or information. Nolother warranties are implied or expressed. In no event shall Engineer of
Record be liable for any special, incidental, indirect, or consequential damages whatsoever (including, without limitation,
damages for loss of business profits, business interruption, loss of business information, or any other pecuniary loss) arising
out of the use of or inability to use information provided.
We appreciate the opportunity to be of service,'. Please contact us if you have questions or require additional assistance.
Sincerely,
First Option Engineering, Inspection, & Construction, LLC
Certificate of Authorization #31724
I,- f - ZG! l/
Greg Arias
Professional Engineer
Florida License #73071 ,
Florida's Leading Engineering Source
Environmental •Geotechnical - Construction Materials Testing - Threshold and Special Inspections • Plan Review & Code Compliance
April 30, 2018.
Mr. Glenn Eberle
65 Aqua Ra Drive
Jensen Beach, Florida 34957
Re: Report of Soil Exploration
Proposed Pool
65 Aqua Ra Drive, Jensen Beach, Florida
Project No. 18-5521.00
GFA International, Inc. (GFA) has completed the subsurface exploration and geotechnical engineering
evaluation for the above referenced project in laccordance with the geotechnical and engineering
service agreement for this project. The scopel of services was completed in accordance with our
Geotechnical Engineering Proposal (18-5521.00), planned in conjunction with and authorized by you.
Field Exploration
GFA initially performed a hand auger boring with hand cone penetrometer (HCP) testing at the above
referenced property on April 13, 2018. Loose Isiity sand soils were encountered in the auger boring
between depths of 8 and 10 feet below the ground surface. To further explore for the presence of
these soils at a greater depth, GFA returned to the site with mechanized drilling equipment on April
24, 2018 and performed a supplemental Standard Penetration Test (SPT) boring to an approximate
depth of 14 feet below the existing ground surface. The SPT and auger borings were performed at the
approximate same location within the footprint of the proposed pool as shown on the attached Test
Location Plan.
The Standard Penetration Test (SPT) and Hand Cone Penetrometer (HCP) test methods were used
as the investigative tools within the borings. The SPT tests were performed in substantial accordance
with ASTM Method D 1586, "Penetration Test and Split -Barrel Sampling of Soils" and the auger
boring in substantial accordance with ASTM Method D 1452, "Practice for Soil Investigation and
Sampling by Auger Borings." 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 failing 30 inches. The number of blows per
foot, for the second and third 6-inch increment, provides an indication of soil strength
HCP tests were conducted at one -foot depth intervals in the auger boring. The HCP test, in
conjunction with information about the soil type, is empirically correlated to the relative density of
subsurface soils.
The soil samples recovered from the soil borings were visually classified and their stratification is
shown on the boring log attached to this report. Note that the soils encountered in both the auger and
SPT borings are presented on one composite log. It should be noted that soil conditions may vary
between the strata interfaces indicated on the log. The soil boring data reflect information from the
specific test location only. The boring depth was established based upon our knowledge of vicinity
soils and confined to the zone of soil likely to be influenced by the planned construction.
607 NW Commodity Cove • Port St. Lucie, Florida 34986 • (772) 924-3575 • (772) 924.3580 (fax) • www.teamgfa.com
OFFICES THROUGHOUT FLORIDA
A Proposed Pool April30, 2018
65 Aqua Ra Drive, Jensen Beach, Florida Page 2
GFA Project No. 18-5521.00
Site specific survey staking for the test locations was not provided for our field exploration. The
indicated depth and location of the test was approximated based upon existing grade and estimated
distances and relationships to the existing residence and other landmarks at the property.
Pool Desian and Construction Recommendations (Ground Supported)
A layer of silty fine sand (SM) was encountered from a depth of approximately 8 to 10 feet below the
ground surface at the 'boring location. Allowing;this soil layer to remain in place may lead to settlement
problems and associated distress within the pool. Therefore, prior to pool construction, we
recommend that these soils be completely removed (excavated) and replaced using clean
sand, and rock/sand mixture, or coarse gravel backfill such as FDOT No. 57 stone.
During the pool excavation, soils that are suitable for reuse as fill should be stockpiled separately. We
expect that the sandy soils (SP, SPASM) encountered above the silty sand soil layer during our field
exploration will be suitable for use as fill material. Organic soils or soils having fines contents of more
than 12 percent should not be used for structural fill next to the pool walls, under the pool deck, or
below any other structure.
The bottom of the pool excavation should be compacted so that the upper 1 foot of .materials achieve
a density of at least. 95 percent of modified Proctor maximum dry density (ASTM D 1557). The
compacted subgrade should be tested by performing in -place density tests or by using a hand cone
penetrometer or probe rod.
The backfill around the sides of the pool should be placed in 6- to 8-inch thick lifts and compacted
using portable equipment until achieving 95 percent of modified Proctor maximum dry density (ASTM
D 1557). The backfill should be clean sand.' having less than 5 percent fines. (percent of dry weight
passing the No. 200 sieve).
If the water table is at or above the bottom of the proposed pool, dewatering may be necessary during
construction. In addition, we recommend that consideration be given to anchoring the pool vessel to
resist potential hydraulic uplift when the pool is empty. Hydrostatic pressure relief valves could also
be installed in the pool bottom.
To reduce the potential for surcharge loading upon the pool side walls resulting from the footings of
the existing residence, the pool should be located so that its side walls that are closest to the existing
residence do not infringe on a 45-degree; downward plane from the horizontal measured from the
bottom edge of the residence footings.
Based upon the above considerations, it m.ay be determined that the organic soils cannot be removed
safely by excavation and backfilling. As an alternative, helical piers or an alternative deep foundation
system may be a viable alternative for support of the pool structure.
Site Excavations
In Federal Register, Volume 54, No. 209 (October 1989), the United States Department of Labor,
Occupational Safety and Health Administration (OSHA) amended its "Construction Standards for
Excavations, 29 CFR, part 1926, Subpart! P." This document was issued to. better insure the safety of
workers entering trenches or excavations. It is mandated by this federal regulation that all
excavations, whether they be utility trenches, basement excavations, or footing excavations, be
constructed in accordance with the OSHA guidelines.
Gf
H
Proposed Pool April 30, 2018
65 Aqua Ra Drive, Jensen Beach, Florida Page 2
GFA Project No. 18-5521.00
The contractor is solely responsible for designing and constructing stable temporary excavations and
should shore, slope, or bench the sides of any excavations deeper than 4 feet as required to maintain
stability of both the excavation sides and bottom. Care must be exercised when performing site
excavations so that caving of excavation side walls will not undermine the footings and slabs
of the adjacent residence or other nearbyl structures. The contractor's responsible person, as
defined in 29 CFR Part 1926, should evaluate the soil exposed in the excavations as part of the
contractor's safety procedures. In no case should slope height, slope inclination, or excavation depth,
including utility trench excavation depth, exceed those specified in local, state, and federal safety
regulations.
GFA is providing this information solely as a service to our client. GFA is not assuming responsibility
for construction site safety or the contractor's, activities. Such. responsibility is not being implied and
should not be inferred.
:O��Z
This consulting report has been prepared for the exclusive use of the current property owner(s) and
members of the design and construction team for the subject project. 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 location of the proposed pool 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 byi GFA
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 Test Location Plan. This report does not
reflect any variations which may occur away from the boring location. While the boring represents the
subsurface conditions at .its specific location and vertical reach, 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 log is approximate and the description represents our interpretation of the
subsurface conditions at the designated boring location on the specific dates drilled.
Analysis of poolfoundation performance under hurricane conditions or other storm events, including
the effects of loss of soil support due to scour or other forces,, is not within the scope of this report.
The recommendations are valid only for normal conditions. Additional analysis and options for
foundation systems with scour conditions or other scenarios can be performed, if requested.
Any third -party reliance of our geotechnical report or parts thereof is strictly prohibited without the
expressed written consent of GFA International, Inc. The applicable SPT methodology (ASTM D
1586) and Auger Boring methodology (ASTM D 1452) used in performing our borings and for
determining penetration resistance is specific to the sampling tools utilized and does not reflect the
ease or difficulty to advance other tools orimaterials.
Gf�
Proposed Pool
65 Aqua Ra Drive, Jensen Beach, Florida
• GFA Project No. 18-5521.00
April 30, 2018
Page 2
We appreciate the opportunity to beofservice to you during this phase of the project and look forward
to a continued association. Please contact the; undersigned if you have any questions or comments,
or if we may further assist you as your plans proceed.
tA
111111��.1.I1�
V
RemKit
Gf 41 AUeJNC.
trondo'C�rtifica e of•Autfi4rization No. 4930
63218.
a 'Ken
ts.oF • lV n Collie, E.I.
Se 'f?rojgg vif,,P
'`�— 3Ov16 r ' c Manager
F16 fiP3218
8�jVnip
'fill 111�\
Attachments: Yest Location Plan
SPT Boring Log (1)
Notes Related to Test Borings;
Distribution: Mr. Glenn Eberle 1 pdf
I
1100 ft
JAJ
N
LOG OF BORING SPT-1
GFA Intematonal PAGE 1 OF 1
CLIENT Glenn Eberle PROJECT NAME Proposed Pool
PROJECT NUMBER 18-5521.00 PROJECT LOCATION 65 Aqua Ra Dr., Jensen Beach
DRILLING CONTRACTOR GFA International Inc. HOLE DEPTH 14 ft 'HOLE DIAMETER
DRILLER MMITM DATE STARTED 4/13/18 COMPLETED 4/24/18
DRILL RIG Simco GROUNDWATER LEVEL: SAT TIME OF DRILLING 6.00 ft
METHOD SPT LATITUDE 27.264623 LONGITUDE-80.206234
NOTE: Top 1Oft w/ Hand Auger and Hand Cone Penetrometer (HCP) HAMMER TYPE
♦ SPT N VALUE
Oz
U
of
}
U
W
W
U
20 40 60 80
PL MC LL
a
¢
=O
m
w
gz
-
Oz
Zz
o"
w"
O
x�
MATERIAL DESCRIPTION
o U
>
O
O¢
m0
>
Ln W
W--1
(fz
20 40 60 80
w
O
¢ Z
W
U
Z
Oz
Z' 0
00
❑ FINES CONTENT (%) ❑
20 40 60 80
Brown fine sand, few rock pieces (SP)
1
35
40
2.5
2
25
15
3
25
5'
5.0
Brown fine sand, trace shell fragments (SP)
i
4
20
20
7.5
Brown silty fine sand, trace shell (SM)
I
5
20
38.8
460
20
10.
10.0
Gray fine sand with shell fragments (SP)
10
6
10
12
22
14
12.0
Gray fine sand (SP)
12.
13
7
14
15
29
i
17
114.0
Bottom of borehole at 14.0 feet.
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.
i
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/CM2
CONSISTENCY
0-4
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
Firm
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 are as follows: i
NAME
SIZE LIMITS
Boulder
12 Inches or more
Cobbles
3 to 12 Inches
Coarse Gravel
% to 3 Inches
Fine Gravel
No. 4 sieve to 3/4 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''/4"
Small roots
12% to 30%
Some
''/4" to 1"
Medium roots
30% to 50%
And i
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
GF�