HomeMy WebLinkAboutLetter; Subsurface InvestigationOrlando: i ih DoW A 7 i AN 1011110 Phone: 772-589-0712
723 Progress Way C.A. # 5693
Sanford, FL. 32771 KSMengineering.net
August 24, 2020
Tony Patton
Patton Construction
845 37th Avenue
Vero Beach, Florida 32960
Re: 10527 Oakbridge Court
Fort Pierce, Florida
KSM Project #: 203962-b
Dear Mr. Patton:
RECEIVED
SEP' 21 2020
Permitting Department
St. Lucie County
a33Z
As requested, KSM Engineering & Testing has performed a subsurface investigation at
the referenced site. Presentation of the data gathered during the investigation, together
with our geotechnical related opinions, are included in this report.
A. Site Description:
At the time of drilling, the site was fairly flat with light surface vegetation (grass) and few
trees.
B. Project Description:
A one-story single-family residence is planned to be constructed on the site. Loads
from the structure will be transferred to the ground by conventional shallow footings.
We estimate the maximum loads will be less than 2,500 pounds per linear foot along the
wall foundation.
Some additional site fill will be required to reach the desired grades.
Proudly Serving Florida since 1990
Orlando: i%s•DwF&VA ANU' MINh
° 723 Progress Way
Sanford, FL. 32771
10527 Oakbridge Court -2-
Fort Pierce, Florida
C. The scope of our study consisted of the following:
Phone: 772-589-0712
C.A. # 5693
KSMengineering.net
August 24, 2020
1. Performed Standard Penetration Test Borings in the proposed construction area
to estimate the subsoil relative density.
2. Measured the groundwater level at each boring.
3. Evaluated the existing soil conditions with respect to the proposed construction
and provided recommendations for site preparation and foundation design.
4. Prepared this report to document our findings.
D. Site Investigation:
The site investigation program consisted of performing four (4) Standard Penetration
Test borings (SPT), in the proposed construction area. The SPT borings were
terminated at depths of 10 to 14 feet below grade. The locations of the borings are
indicated on the attached boring logs.
The SPT borings were completed in accordance with procedures described in ASTM D-
1586. A standard 1.5 inch I.D., 2 inch O.D. split -spoon sampler is driven into the soil by
successive blows of a 140 pound hammer freely falling 30 inches. The number of blows
required to drive the sampler 1 foot, after seating 6 in., is designated the Penetration
Resistance, or "N" value. At regular intervals the sampler is extracted from the ground
and opened to allow visual examination and classification of the retained soil sample.
Also, the groundwater table was allowed to stabilize and the depth of the groundwater
elevation recorded from existing grade.
The records of the soils encountered, the penetration resistances and groundwater level
are shown on the attached logs.
Proudly Serving Florida since 1990
Orlando: i i140 A V A A i u ,' La' II�1� N U
• 723 Progress Way
Sanford, FL. 32771
10527 Oakbridge Court -3-
Fort Pierce, Florida
E. Engineering Evaluation and Conclusions:
Phone: 772-589-0712
C.A. # 5693
KSMengineering.net
August 24, 2020
Based on the information obtained from this site investigation, we are pleased to offer
the following evaluation:
The boring logs indicate the subsurface conditions to be fairly uniform across the site.
The soils consist mostly of fine-grained sand, slightly silty or slightly clayed sand, and
clayed sand. "N" values recorded during the boring operation indicate the soil density is
generally medium dense to a depth of approximately 10 feet below existing grade and
then the soils became loose. Please refer to the soil boring logs for specific information
relative to the soil description.
Based on the existing soil conditions, the proposed structure can be supported on a
shallow foundation system provided that the site is properly prepared.
The following sections provide recommendations for the site preparation and foundation
design.
F. Site Preparation:
The proposed building area and areas to be paved, plus a minimum margin of five feet
beyond- the proposed construction shall be stripped and grubbed of surface debris,
including vegetation, roots and organic matter. Stumps shall be removed entirely. The
building area should be graded level and proofrolled. Any soft yielding areas shall be
excavated and replaced with clean compacted fill. Sufficient passes should be made
during compaction operations to produce a density no less than 95 percent of its
modified dry Proctor value (ASTM D 1557) to a depth of two feet.
After the exposed surface has been proofrolled, the building and pavement areas may
be filled to the desired grades. The fill material shall consist of clean granular sand
containing less than 10% material passing the U.S. Standard No. 200 mesh sieve.
Place structural fill in loose layers of 12 inches in thickness and compact each lift to at
least 95 percent of its modified dry Proctor value.
After excavating for the footings, the disturbed footing subgrade should be recompacted
to 95 percent (minimum) of its modified dry Proctor value. This can be best achieved by
making several passes with a relatively light -weight walk -behind vibratory sled or roller.
Proudly Serving Florida since 1990
oriando: i INa/ A r S H11 U I CJ I l II U Phone: 772-589-0712
• 723 Progress Way C.A. # 5693
Sanford, FL. 32771 KSMengineering.net
10527 Oakbridge Court -4- August 24, 2020
Fort Pierce, Florida
G. Foundation:
Provided that our recommendations for site preparation are followed, the proposed
structure may be supported on conventional concrete, steel reinforced footings
designed for an allowable soil bearing pressure of 2,500 pounds per square foot, or
less.
With the foundation properly designed and the site properly prepared, we anticipate
total settlements less than 3/ of an inch and differential settlement of less than %4 of an
inch. The majority of the settlement should occur during construction.
H. Floor Slabs:
A conventional slab -on -grade can be used in the "at grade" portion of the building. We
recommend the disturbed subgrade below the floor slab be re -compacted to 95 percent
of the modified Proctor maximum dry density (ASTM D 1557) prior to placement of the
concrete. An estimated modulus of subgrade reaction of 150 pounds per cubic inch
(pci) can be used for design of the slab -on -grade. We recommend that control joints be
incorporated in the slab at frequent intervals to control shrinkage cracks.
A moisture barrier is recommended beneath the floor slab to prevent moisture migration
from the underlying soil resulting in dampness of the slab.
I. Pool (If Constructed):
Based on the existing soil conditions, a pool can be designed and constructed using an
allowable soil bearing pressure of 2,500 pounds per square foot.
When excavating the pool, if any organic soil or soft material is encountered, these
materials/soils should be removed and replaced with 3/" stones so the subgrade
becomes firm below the pool bottom.
Backfill material behind the pool shell shall consist of clean granular sand with less than
10 percent "fines" passing the U.S. No. 200 sieve. Place backfill material in loose lifts of
12 inches in thickness and compact each lift to no less than 95 percent of its modified
dry Proctor value (ASTM D 1557).
Proudly Serving Florida since 1990
Orlando: &Mm"iTi AMU 1011 \U Phone:772-589-0712
723 Progress Way C.A. # 5693
Sanford, FL. 32771 KSMengineering.net
10527 Oakbridge Court -5- August 24, 2020
Fort Pierce, Florida
J. Closure:
This report has been prepared in accordance with generally accepted soil and
foundation engineering practices based on the results of the test borings and the
assumed loading conditions. No warranties, either expressed or implied, are intended
or made. This report does not reflect any variations which may occur between the
borings. If variations appear evident during the course of construction, it would be
necessary to re-evaluate the recommendations of this project.
Environmental conditions, wetland delineation, water quality, and municipal
requirements are not a part of this report.
We are pleased to be of assistance to you on this phase of your project. When we may
be of further service to you or should you have any questions, please feel free to
contact us.
J Eft
E-mail to: apatton@pattonconst.com
Proudly Serving Florida since 1990
CLIENT Patton Construction
PROJECT NAME 10527 Oakbridge Court
PROJECT NUMBER 203962-b
PROJECT LOCATION Fort Pierce Florida
DATE STARTED 8/21/20 COMPLETED 8/21/20
GROUND ELEVATION
HOLE
SIZE inches
DRILLING CONTRACTOR
GROUND WATER LEVELS:
DRILLING METHOD Split Spoon Sample
�-Z AT TIME OF DRILLING 3.08 ft
LOGGED BY MS/MH CHECKED BY JEK
AT END OF DRILLING --
NOTES See Attached Location Plan
AFTER DRILLING --
wn.
o
z
A SPT N VALUE A
~^
U
a0
UJm
>
Ul
w
z-3
a
1=
20 40 60 80
PL MC LL
a.
O
MATERIAL DESCRIPTION
M
> 0
O Q
z CL
p—�
o
CD
z
Ov
m O z
U"
}
20 40 60 80
<
W
d
0
0 FINES CONTENT (%) ❑
0
20 40 60 80
Gray Sand with Some Roots
::'•': t:
Dark Brown Sand
5 -6-7
:.......:.......:.......:......
SS
(13)
=
Gray Sand, Slightly Clayed
- Gray Sand, Slightly Silty
SS
10-10-11
(21)..
............................
5
Brownish Gray Sand, Slightly Clayed
7-7-7
•:.
SS
(14)
:.......:.......:.........
::,....
SS
5-6-7
.....................................
;:;:
SS
4-4-4
(8)
:.......:.......:.......:.
2-1-2
......................
.• .
Dark Brown Clayed Sand
F
(3)
""'2-2-2.:.....Light
Gray Clayed Sand
IA%
......" """ "' " """
of borehole at
p
a
CLIENT • Patton Construction
PROJECT NAME 10527 Oakbridae Court
_
PROJECT NUMBER 203962-b
PROJECT LOCATION Fort Pierce, Florida
DATE STARTED 8/21/20 COMPLETED 8/21/20
GROUND ELEVATION
HOLE
SIZE inches
DRILLING CONTRACTOR
GROUND WATER LEVELS:
DRILLING METHOD _Split Spoon Sample
AT TIME OF DRILLING 3.00 ft
LOGGED BY MS/MH CHECKED BY JEK
AT END OF DRILLING —
NOTES See Attached Location Plan
AFTER DRILLING —
a
a
Z
A SPT N VALUE
~
U
= c9
0:
r W
}
0:
w
D
W
a
20 40 60 80
PL MC LL
-,
w v
0-0
MATERIAL DESCRIPTION
2
j C�
o Q
W a
'"
z m
o
z
U S
m V Z
v
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20 40 60 80
<
ui
a
W
❑ FINES CONTENT (%) C3
0
20 40 60 80
Gray Sand with Some Roots
.
Dark Brown Sand
SS
5-5-7
(12)
"'""""""" """"
............. ........ ....... .:......
.......... ....... ........ :......
..............
:....... :....... ....... :......
:....... :......
Gray Sand, Slightly Clayed
.:
• ..
Gray Sand, Slightly Silty
SS
7-8-10
(18)
SS
6 6-7
(13)
•:
:, ..
• :
Brownish Gray Sand, Slightly Clayed
SS
5-5-5
(10)
SS.......
5-5-4
(9)
Bottom of borehole at 10.0 feet.
J
CLIENT Patton Construction
PROJECT NAME 10527 Oakbridae Court
PROJECT NUMBER 203962-b
PROJECT LOCATION Fort Pierce, Florida
DATE STARTED 8/21/20 COMPLETED 8121/20
GROUND ELEVATION HOLESIZE
inches
DRILLING CONTRACTOR
GROUND WATER LEVELS:
DRILLING METHOD Split Spoon Sample
AT TIME OF DRILLING 3.17 tt
LOGGED BY MS/MH CHECKED BY JEK
AT END OF DRILLING —
NOTES See Attached Location Plan
AFTER DRILLING ---
w
♦ SPT N VALUE
U
CL
W
w
20 40 60 80
o.CLO
MATERIAL DESCRIPTION
-1g
Ci
O � ¢
w
z
z a
�0
20
ov
OJ
o-z
V�
m0z
Uv
40 60 80
❑ FINES CONTENT (%) ❑
<
Lu
.�
a
ce
Gray Sand with Some Roots
Dark Brown Sand
Gray Sand,
Dark Gray Clayed Sand
R
C*
SS
6-5-7
(12)
.
......................................
... ... .... ....
.... ... ....
..... :.......:.......:.......:......
:.......:.......:.............
.....................................
... ... .... ....
.....................................
.......:...................
.....................................
..... ....... ....... ....... :......
....... :....... :....... ....... :......
SS
9-10-11
(21)
Clayed
SS
8-7-7
(14)
SS
6-7-6
(13)
SS
5-4-4
(8)9—
SS
3-2-1
(3)
SS2-2-2
(4)
>rehole at 14.0 feet.
CLIENT Patton Construction
PROJECT NAME 10527 Oakbridge Court
PROJECT NUMBER 203962-b
PROJECT LOCATION Fort Pierce, Florida
DATE STARTED 8/21/20 COMPLETED 8/21120
GROUND ELEVATION HOLE
SIZE inches
DRILLING CONTRACTOR
GROUND WATER LEVELS:
DRILLING METHOD _ Split Spoon Sample
Q AT TIME OF DRILLING 3.08 ft
LOGGED BY MS/MH CHECKED BY JEK
AT END OF DRILLING —
NOTES See Attached Location Plan
AFTER DRILLING --
W
o
W
A SPT N VALUE A
U
o:
>•
rn w
n
20 40 60 80
PL MC LL
-,
n-
= C9
O
MATERIAL DESCRIPTION
w
WE
j a
g~ 3
O=¢
w y
z CL
pv
a.Z
v�
mOZ
V"
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20 40 60 80
❑ FINES CONTENT (%) ❑
O'�
L
v
a
M
Gray Sand with Some Roots
:.......:......:.......:......
• • •
....................................
Dark Brown Sand
SS
6-7-9
(16)
...
Gray Sand, Slightly Clayed
:.
..
Gray Sand, Slightly Silty
SS
6-6-5
..
(11)
Brownish Gray Sand, Slightly Clayed
7-7-6
: '
SS
(13)
'
.....................................
SS
7-6-7
(13)
SS
5-5-4
.. .
.......:.......:.......:......
(9)
Bottom of borehole at 10.0 feet.
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PROJECT: 10527 Oakbridge Court, Fort Pierce, Florida