HomeMy WebLinkAboutSubsurface InvestigationAugust 28, 2019
First Choice Renovations, Inc.
120 SE 13t' Street
Pompano Beach, FL 33060
RE: Subsurface Investigation
1.00 Ac. Residential Lot
5242 Slash Pine Trail
Fort Pierce, FL 34951
3931 SW 47TH Avenue, Suite 104
Davie, Fl. 33314
Tel: 954-584-6115
E-mail: ppeana@soilprobe.net
A
J U N 2 2 2020
.ST. Lucie County, Permitting
In accordance with your request and authorization, Soilprobe Engineering & Testing, Inc. has
completed subsurface exploration and geotechnical studies at the above referenced project site. We
explored the general subsurface conditions in order to evaluate their suitability for supporting the
anticipated construction, and to provide recommendations for site preparation and foundation design.
Our work included standard penetration test (SPT) borings and engineering analyses. This report
describes our explorations and tests, reports their findings, and presents our recommendations
developed from the investigation.
Our report has been prepared specifically for this project. It is intended for the exclusive use of First
Choice Renovations, Inc. their representatives and/or assigns. Our work has used methods and
procedures consistent with local foundation engineering practices. No other warranty, expressed. or
implied, is made. We do not guarantee project performance in any respect, only that our work meets
normal standards of professional care.
We understand that the vacant land is being considered as residential site for anew one-story residence.
and an auxiliary structure. At the time of our tests the site lightly wooded with scattered pine trees and
mostly covered with underbrush, weeds and vines. The property configuration, locations of proposed
construction and approximate locations of our soil tests are presented in the attached plot plan. The
proposed house will be constructed of conventional poured in place concrete and concrete masonry
unit (CMU). Bearing walls will be supported by shallow continuous and isolated footings designed for
an allowable soil bearing capacity of 2,500 PSF and concrete slab placed on compacted subgrade. The
auxiliary building will consist of pre-engineered steel framed structure with steel columns to be
supported by isolated, spread footings designed for an allowable soil bearing capacity of 2,500 PSF.
Concrete slab will be placed on grade and poured separate from foundations and columns.
First Choice Renovations, Inc.
Proposed Residence
5242 Slash Pine Trail
August 28, 2019
Page 2 of 4
Subsurface conditions at the site were explored with three (3) engineering borings advanced to a depth
of 14 feet below existing ground surface. Our representatives selected the test locations in the field
within the area of proposed construction as shown in the attached location test. Samples of the in -place
materials were recovered at frequent intervals with a standard 24 inches split barrel sampler driven into
the ground with a 140-pound hammer falling 30 inches. This work was performed on August 21, 2019
following closely the procedures recommended in ASTM Method D-1586.
Detailed subsurface conditions encountered at the locations and depth explored are presented in the
attached logs. Our drillers examined the soil recovered from the SPT sampler and maintained a log for
each boring. Soil samples were inspected and classified with the Unified Soil Classification System
(USCS). Classifications and other pertinent data obtained from our explorations and tests are reported
on the attached boring logs. Soil stratification, shown on the boring logs, is based on examination of
recovered soil samples and interpretation on the driller's field logs. It indicates only the approximate
boundaries between soil types: The actual transitions between the adjacent soil strata may be gradual
and indistinct.
Generally, the tests revealed a surfacing layer of topsoil with roots with a thickness of approx. 8-inch.
Below this surfacing layer and continuing to the boring termination depth, the soil consisted of layered
gray, tan and brown sand.. Standard penetration resistance, N-value, recorded during the tests,
indicated soil conditions as loose in the upper 3 to 4 feet, and in a medium dense condition at deeper
locations to medium dense.
Groundwater measured at the time of test was found at a depth of approximately 4.00 feet below
prevailing grade. Fluctuations in ground water level should be anticipated throughout the year due to
seasonal variations in rainfall, drainage and other factors. The groundwater level measured at the time
of test is not intended to define a limit or ensure that future seasonal fluctuations in groundwater levels
will not vary from this level. We recommend that the Contractor determine the actual water table at the
time of the construction to determine groundwater impact on his construction procedures.
It is our opinion that the soil at the site is generally suitable to support the proposed building on
conventional shallow foundations. However, compaction of the existing loose sand layers and any
added fill. material is required; if they are to support the shallow foundations, in order to avoid
excessive settlements that may be detrimental to the structure.
The following site preparation procedures are recommended prior to the installation of the foundations
or slab on grade:
First Choice Renovations, Inc.
Proposed Residence
5242 Slash Pine Trail
August 28, 2019
Page 3 of 4
Clear and grub the proposed building area plus a perimeter of minimum five feet outside the
foundation limits and any area which is to support slab on grade removing existing vegetation,
roots, trees and tree roots system. The thickness of the surfacing dark sand with roots to be
removed is expected to be approximately 12 inches. This clearing, stripping and grubbing shall
extend a minimum 10.00 feet outside buildings perimeters.
2. Level and proof roll the building areas with a medium heavy (25-ton) vibratory roller with
minimum 20 passes each direction. Any soft spots, revealed by proof rolling operation, shall be
excavated and replaced with clean, compactable fill material. This proof -rolled operation shall
bring the loose sandy soils to a minimum 98% of maximum dry density as determined by
ASTM Method D-1557. Field density tests shall verify the achieved compaction prior placing
any fill material.
3. Once the excavated building pads areas are inspected by a geotechnical engineer representative
and field density tests verified for achieving minimum density of 98% the building areas may
be filled to the design elevations using stockpiled material or clean imported fill material,
consisting of sand or sand rock mixture, free of organic and other deleterious materials and
containing not more than eight percent passing the No. 200 sieve and having rocks not larger
than 3 inches. Fill material shall be tested before being delivered and used on jobsite. The fill
shall be placed and compacted, in lifts not exceeding 12 inches in loose thickness, to a
minimum 95% of maximum dry density.
The building pads areas, prepared in accordance with the above site preparation recommendations,
should be suitable to support the proposed structure on conventional shallow foundation designed for
an allowable bearing capacity of 2,500 PSF. We also recommend that continuous strip and/or
monolithic footings to be minimum 20 inches wide, and all isolated column footings to be at least 36
inches square
Further, we recommend the use of spread footings to support the proposed bearing walls and columns
with base of footings placed at a minimum 24 inches below post -construction, adjacent grades.
Concrete slab may be placed on compacted subgrade poured separate from the walls and column
footings (stem -wall type construction) or poured monolithically with foundations. For monolithic slab
and footing design, ample consideration shall be given to the eccentric loading, foundation rotation and
increased shear stress at the slab and footing interface.
The yard final grading shall divert and convey storm water runoff away from foundation walls by
sloping the grade away from structure in order to protect the foundation. Roof gutters also may be
installed to collect, convey and discharge the water a minimum 5.00 feet from walls.
Any modification to the above -recommended procedures should be approved by Soilprobe
Engineering &Testing, Inc.
First Choice Renovations, Inc.
Proposed Residence
5242 Slash Pine Trail
August 28, 2019
Page 4 of 4
Further, in order to verify compliance with these specifications and document construction
procedures used and actual conditions encountered we suggest that Soilprobe Engineering &
Testing, Inc. be retained to test the compacting effort on this project. This office does not accept any
responsibility for any conditions that deviate from those described in this report, nor for the
performance of the foundation if not engaged to provide construction observation, testing and
certification for this project.
Due to the fact that soils are generally, naturally deposited materials under variable conditions, it must
be understood that major subsurface discontinuity may occur within short distances. It is unlikely that
the tests used for this investigation revealed all subsurface conditions.
Our office does not warrant or imply that the data collected on our log of borings are indicative of the
subsurface features, except the locations where borings were taken. If unusual or variant conditions are
found during construction, please notify this office for further evaluation and recommendation.
This report represents an accurate appraisal of the site conditions upon careful interpretation of the
physical data, to the extent reasonably possible. If variant or unusual soil conditions are found during
construction, this office shall be notified for further testing, evaluation, and recommendation.
Sincerely,
G & TESTING, INC.
Enc. Soil Logs
SPT Appendix
Plot -Plan -
LOG OF BORING
JOB #:..
1 11� '
Sheet:
1 of 1
Boring:
1
Date:
8/28/19
CLIENT:
First Choice Renovations, Inc.
Date started:
8/21/19
PROJECT:
5242 Slash Pine Trail Fort Pierce,'FL 34951
Date completed:
8/21/19
LOCATION:
'See sketch
Driller s :
PP/AO/JP
AZ
.v
3
a
DESCRIPTION:
Soil type, color, texture, and consistency. .
Notes on drilling conditions.
0.00
=
0'-011
Weeds, vines
Dark sand, roots
Dark grey sand
sand
.
Tan reddish sand
Pale tan greyish sand
End of test 14'-0"
1
3
20
0'-8"
2, _0„
3'-6"
4'-6"
' 6'-0"
7E_071
14'-0"
'.°°
1
2
2.00
2
3
8
20
1Grey
3.00
4
4
4.00
5
5
11
23
5.00
5
6.00
6
9
20
24
7.00
- 10
10
8.00
11
11
21
24
9.00
10
11
10.00
11
14
32
24
11.00
16
16
12.00
17
19
38
24
13.00
20
18
14.00
18
15.00
16.00
17.00
18.00
19.00
20.00
TYPE of SAMPLE: Cohesionless Density: Cohesive Consistency:
D — disturbed (2) — Penetrometer 0-10 Loose 0-4 Soft
U.L.- Undist. Liner 10-30 Medium 4-8 Medium Stiff
S.T.— Shelby tube 30-50 Dense 8-15 Stiff
S.S. — Sample Spoon 50+ Very dense 15-30 Very Stiff
R.C. —Rock Core 30+ Hard
140 Lb. WT. Hammer x 30" fall on T' sampler
LOG OF BORING
JOB #:
Sheet:
1 of 1
Boring:
2
Date:
8/28/19
CLIENT:
First Choice Renovations, Inc.
Date started:
8/21/19
PROJECT:
5242 Slash Pine Trail Fort Pierce, FL 34951
Date completed:
8/21/19
LOCATION:
See sketch
Driller s :
PP/AO/JP
AZ
c
3
a Y
DESCRIPTION:
Soil type, color, texture, and consistency.
Notes on drilling conditions.
0.00
o'-o"
Weeds, vines
Dark grey sand
Grey sand
Brown dark sand
Tan reddish sand
Tan to greyish sand
End of test 14'-0"
2
5
18
0'-6"
4'-0"
6'-6"
6'-6"
10'-0"
14'-0"
1.00
2
3
2.00
4
4
12
22
3.00
6
6
4.00
5
6
13
24
5.00
6
6.00
8
8
19
24
7.00
9
10
8.00
10
11
20
24
9.00
11
9
10.00
10
12
27
24
11.00
14
13
12.00
15
16
33
24
13.00
16
17
14.00
16
15.00
16.00
17.00
18.00
19.00
20.00
TYPE of SAMPLE: Cohesionless Density: Cohesive Consistency:
D — disturbed (2) — Penetrometer 0-10 Loose 0-4 Soft
U.L.- Undist. Liner 10-30 Medium 4-8 Medium Stiff
S.T. — Shelby tube 30-50 Dense 8-15 Stiff
S.S. — Sample Spoon 50+ Very dense 15-30 Very Stiff
R.C. — Rock Core 30+ Hard
140 Lb. WT. Hammer x 30" fall on 2" sampler
LOG OF BORING
JOB #:
Sheet:
1 of 1
Boring:
3
Date:
8/28/19
CLIENT:
First Choice Renovations, Inc.
Date started:
8/21/19
PROJECT:
5242 Slash Pine Trail Fort Pierce, FL 34951
Date completed:
8/21/19
LOCATION:
See sketch
I Driller s :
PP/AO/JP
aSoil
DESCRIPTION:
type, color, texture, and consistency.
Notes on drilling conditions.
0.00
—_
01-099
Weeds, vines
Dark sand with large pieces of roots
Grey sand
Brown dark sand
Tan reddish sand
End of test 14'-0"
3
9
22
1'-011
4'-6"
6'-6"
6'-6"
14'-0"
1.00
5
4
2.00
5
4
10
22
3.00
4
6
4.00
6
5
14
24
5.00
6
8
6.00
9
16
24
' °°
8
8
8.00
9
9
21
24
9.00
11
10
10.00
11
11
23
24
11.00
12
11
12.00
12
12
27
24
13.00
14
13
14.00
15
15.00
16.00
17.00
18.00
19.00
20.00
TYPE of SAMPLE: Cohesionless Density: Cohesive Consistency:
D — disturbed (2) — Penetrometer 0-10 Loose 0-4 Soft
U.L.- Undist. Liner 10-30 Medium 4-8 Medium Stiff
S.T. — Shelby tube 30-50 Dense 8-15 Stiff
S.S. — Sample Spoon 50+ Very dense 15-30 Very Stiff
R.C. — Rock Core 30+ Hard
140 Lb. WT. Hammer x 30" fall on 2" sampler
1 inch equals feet
Lot size 166.64' x 272-22'
.+
® I�k
Setback from property
front approx- 60-75'
exact location to be
determined based on
somewhat existing
driveway
50 t%,-MSV �,o CP-TkON
SL�SI-F �� N E T IZ.A• 1l.
TtALT - Ple (icE
_-
3931 SW 4r Avenue Suite 104
Davie, Fl. 33314
Tel: 954-584-6115
Fax:954-584-2862
E-mail: ppeanai@soilprobe.net
APPENDIX "A"
SUBSURFACE EXPLORATION INFORMATION
Our borings describe subsurface conditions only at the locations drilled and at the time drilled. They provide no
information about subsurface conditions below the bottom of the boreholes. At locations not explored, subsurface
conditions that differ from those observed in the borings may exist and should be anticipated.
The groundwater depth shown on our boring logs is the water level the driller(s) observed in the borehole when it
was drilled. These water levels may have been influenced by the drilling procedures. An accurate determination of
groundwater level requires long-term observation of suitable monitoring wells. The absence of a groundwater level
on certain logs indicates that no groundwater data is available. It does not mean that no groundwater will be
encountered at that boring location.
Standard Penetration Test Borings
The Standard Penetration Test (SPT) is a widely accepted method of testing foundation in place. The N-value
obtained from the test has been correlated empirically with various soil properties. These empirical correlations
allow satisfactory estimates to be made of how the soil is likely to behave when subjected to foundation loads. Tests
are usually performed in the boreholes at intervals of five feet. In addition, our Firm performs tests continuously in
the interval directly below the expected foundation -bearing grade where the soil will be most highly stressed.
Boreholes where SPT will be performed are drilled with a truck mounted SIIVICO 2800 drill -rig. The boreholes are
advanced by rotary drilling with a winged bit that makes a hole about seven inches in diameter. After the borehole
has been advanced to the depth where a SPT will be performed, the soil sampler used to run the test is attached the
end of drill rods and lowered to the bottom of the borehole. The testing procedure used conforms closely to the
methods recommended in ASTM D-1586. The sampler has a split -barrel 24 inches long and an outside diameter of
2.0 inches. It is driven into the ground below the bottom of the borehole using a hammer that weights 140 pounds
and falls freely 30 inches. The driller records the number of hammer blows needed to advance the sampler the
second and third six-inch increments. The total number of blows required to advance the sampler the second and the
third six-inch increments constitutes the test results; that is N-Value at the depth. The test is completed after the
sampler has been driven not more than 24 inches or when refusal is encountered, whichever occurs first. Refusal
occurs when 100 hammer blows advance the sampler six inches or less.
After the test is completed, the sampler is removed from the borehole and opened. The driller examines and
classifies the soil recovered by the sampler. He places representative soil specimen from each test in closed jars or
plastic bags and takes them to our laboratory. In the laboratory, additional evaluations and tests are performed, if
needed. Jar samples are retained in our laboratory for thirty days, then discarded unless our clients request
otherwise.
Hand Auger Borings
Hand auger borings are used if soil conditions are favorable, when the soil strata are to be determined within a
shallow (approximately 6 feet) depth, or when access is not available for our truck -mounted or portable mounted
drill -rigs. A three inches diameter hand bucket auger with a cutting head is simultaneously turned and pressed into
the ground. The bucket auger is retrieved at approximately six inches increments and its content emptied for
inspection. Sometimes posthole diggers are used, especially in the upper three feet or so. The soil samples obtained
are described and representative samples put in jars or plastic bags and transported to the laboratory for further
classification and testing, if necessary.