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November 17, 2016
Phoenix Realty Homes, Inc.
Attention: Alan Tarpell
1760 N. Jog Road, Suite 140
West Palm Beach, Florida 33411 OR IGIN A L
RE: Soil Exploration Addendum #2 - Helical Piers for Pool
Proposed One -Story Residence
121 Queen Gunevier Court, Fort Pierce, Florida
GFA Project # 16-1614.01
(Reference GFA Geotechnical Report # 16-1614.00 dated 7/26/2016)
(Reference GFA Report # 16-1614.01 Report of Test Pits and Auger Borings dated 11/16/2016)
Dear Mr. Tarpell:
GFA International was requested to provide helical pile recommendations for pool support at the
above referenced project. The subsurface exploration activities from reports referenced above were
performed in accordance with Chapter 18 of the Florida Building Code (latest addition) and applicable
ASTM standards. The boring logs and site plans are attached to this report for reference. Helical pile
recommendations are provided below based on the borings.
Pile Foundation (Helical Piers)
Helical piers consist of galvanized steel shafts with helical flight augers on the bottom shaft. The shafts
are bolted together as the shafts are drilled into the subsurface. The torque applied to the piers during
drilling is correlated to the compression capacity of the helical pier. The shafts are cut to the appropriate
cut-off elevation, and typically pile caps, grade beams, or footings are cast on the top of the helical
piers.
Helical piers for these type of structures generally require a 4 to 12 ton capacity. We recommend the
piers be spaced at least 3 diameters (largest helical diameter) apart center -to -center. To obtain
required axial capacity, the piers would likely have to be installed and seated into the medium dense
to very dense sand encountered from about 18%z to 35 feet below existing grade. The length of the
piers could extend beyond 35 feet before achieving the required torque and corresponding
capacity.
Each pier must be installed with a minimum of twice their design capacity. The capacity of several
piers must be verified by shear pins or other calibration techniques as required by the Florida Building
Code. 2010 ed as noted below.
521 NW Enterprise Drive - Port St. Lucie, Florida 34986 • (772) 924.3575 • (772) 924-3580 (fax) • www.teamgfa.com
OFFICES THROUGHOUT FLORIDA
Soil Exploration Addendum(,-' ';!Helical Piers for Pool
1121 Queen Gunevier Court, V __,,,Pierce, FL
GFA Project# 16-1401.01
November 17, 2016
In accordance with Section 1810.3.3.1.9 of the Florida Building Code, 2010 ed, the allowable axial
design load, Pa, of helical piles shall be determined as follows:
Pa = 0.5 P„ (Equation 18-4)
where P„ is the least value of:
1. Sum of the areas of the helical bearing plates times the ultimate bearing capacity of the soil or
rock comprising the bearing stratum.
2. Ultimate capacity determined from well -documented correlations with installation torque.
3. Ultimate capacity determined from load tests.
4. Ultimate axial capacity of pile shaft.
5. Ultimate axial capacity of pile shaft couplings.
6. Sum of the ultimate axial capacity of helical bearing plates affixed to pile.
Helical pier design and installation is proprietary in nature. The locations and required capacity of the
piers must be designed by the structural engineer or other qualified professional. Helical pile support
recommendations are based on the existing structures (including existing footings and slabs if
applicable) having structural integrity which will be determined by others. GFA recommends that a
representative of GFA monitor the helical pier installation in accordance with the Florida
Building Code.
Installation of piers should be performed after all utilities have been identified and located to avoid
installation problems and for safety reasons. These services were not within our scope of services.
Fill and backfill should be "clean" sand with less than 5% fines (percent of dry weight passing a U.S.
No. 200 sieve). The fill (including backfill around pile caps and grade beams) should be placed in 12-
inch thick compacted lifts with each lift compacted to at least 95% of the modified Proctor maximum
dry density (A�TV`111697h, J'
The compaction should be checked with field density tests.
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Sincerel)$�,��i: • -9 `moo
GFA In �o�al, Inco n �p
FBPE �_ 3
Donald V1��,�f(er.,.P.E.....•' 'a`�� C i an Collie, E.I.
Senior Geol.'e�,�f Yg6g1n ftO P j t Manager
Florida Reg istr��i�nitlw4t975
Attachments: Attachments from GFA Geotechnical Report # 16-1614300 dated 7/26/2016 (7 pages)
Attachments from GFA Report # 16-1614.00 Report of Test Pits and Auger Borings
dated 11/16/2016 (4 pages)
Copies: Client (2)
.A
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1994 Imagery Date: 1/23/2016 lat 27.515805O2
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Test Location Plan
121 Queen Gunevier Court
Fort Pierce, FL
GFA Project No. 16-1614.00
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+ Approximate Standard Penetration Test (SPT) Boring & Auger Boring (AB) Locations
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, Inc. Project No.:16-1614.00
Lab No.:
Project: 121 Queen Gunevier Ct. Page: 1 of 2
Fort Pierce, FL Date: 7/12/2016
Elevation: Existing Grade Drill Rig: Simco-24
Water Level: 6 feet after 0 hours Drilling Fluid commenced at depth of 10 feet Field Party: JS/ES
TEST LOCATION: SPT - 1 N27.5155400 W80.3225490
Laboratory Tests
Depth
Blows/
N
Sample
Layer:
USCS
Description
Passing
Moisture
Organic
(feet)
6 in.
Value
No.
From/to
No. 200
Content
Content
2
0 - 6h
SP
Light brown fine sand
6�
10
1
•9..........
--- 3
--2 - 9 ---
- ----
9
18
2
_7.
----
5
8
------
......7
9
3
---- 6
_13
...
5
6'Y2 - 8
SP-SC
Gray fine sand, little silt and clay
8
_ _
_-----
10
18
4
8
••
8-9
SM,ML
Gray silt and sand
WOH
_
1
WOH=Weight of Hammer
3
4
5
9-10
SP
Gray fine sand, trace shell
--- 10....
-
---
11
-------
------
12
..............
13
-------
------
14
WOH
-------
13Y2 - 15
SM,ML
Gray fine sand and silt and shell
WOH
WOH=Weight of Hammer
----15
- 3-
.3.
6
16
----
---
17
----
---
18
..............
18%2 - 20
SP
Gary fine sand and shell
19
..47 _-
______
38
33
71
7
1 J
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, Inc. Project No.:16-1614.00
Lab No.:
Project: 121 Queen Gunevier Ct. Page: 2 of 2
Fort Pierce, FL Date: 7/12/2016
Elevation: Existing Grade Drill Rig: Simco-24
Water Level: 6 feet after 0 hours Drilling Fluid commenced at depth of 10 feet Field Party: JS/ES
TEST LOCATION: SPT - 1 N27.5155400 W80.3225490
Laboratory Tests
Depth
(feet)
Blows/
6 in.
N
Value
Sample
No.
Layer:
From/to
USCS
Description
Passing
No. 200
Moisture
Content
Organic
Content
20
-------
----
21
----
---
22
----
---
23
..............
24
-9 _
10
-----
23'/2 - 25
SP
Gray fine sand, trace shell
---- 25
-_ 15 .......25.....
8
26
..............
27
----
---
28
..............
29
--12.........
18
28'/2 - 30
SP
Dark gray fine sand
---- 30
_26
44
9
31
----
---
32
..............
33
•...
•--
34
-14 .........
33'/2 - 35
SP
Dark gray fine sand and shell
20
35
..26 -_
_ 46_ _
10
37
----
---
38
----
---
39
9 ..........
2
38'/2 - 40
CH
Gray silt and clay, some sand
1
3
11
Boring terminated at 40 feet
010- Since 1988
Florida's Leading Engineering Source
AUGER BORING LOGS WITH HAND CONE PENETROMETER (HCP) TESTS
Client: Phoenix Realty Homes, Inc.
Project: 121 Queen Gunevier Ct.
Fort Pierce, FL
Elevation: Existing Grade
Project No:
Lab No:
Test Date:
Technician:
16-1614.00
7/12/2016
JS/ES
TEST LOCATION: AB — 1 N27.5155080 W80.3223600
HCP
Depth (feet)
Description (color, texture, consistency, remarks)
Depth
Reading
0-2
Gray fine sand SP
1
70
2-5
Dark gray fine sand, some silt and clay SC
2
45
5-8
Dark gray fine sand, trace shell SP
3
80+
8-10
Gray silt and sand SM,ML
4
1 80+
5
60
6
25
7
20
8
15
9
10
10
15
Water table at 5 feet below ground surface
TEST LOCATION: AB — 2 N27.5154970 W80.3222600
HCP
Depth (feet)
Description (color, texture, consistency, remarks)
Depth
Reading
0-2
Light brown fine sand SP
1
45
2-4
Gray fine sand, trace shell SP
2
55
4-9
Gray fine sand, some silt and clay SC
3
70
9-10
Gray fine sand, some shell SP
4
1 80+
5
60
6
50
7
35
8
15
9
20
10
10
Water table at 5.5 feet below ground surface
Florida's Leading Engineering Source
AUGER BORING LOGS WITH HAND CONE PENETROMETER (HCP) TESTS
Client: Phoenix Realty Homes, Inc.
Project: 121 Queen Gunevier Ct.
Fort Pierce, FL
Elevation: Existing Grade
Project No:
Lab No:
Test Date:
Technician:
16-1614.00
7/12/2016
JS/ES
TEST LOCATION: AB — 3 N27.515571 ° W80.3223600
HCP
Depth (feet)
Description (color, texture, consistency, remarks)
Depth
Reading
0 - 2'/2
Light brown fine sand SP
1
55
2'/2 - 6
Gray fine sand, trace shell SP
2
65
6 - 10
Gray fine sand, some silt and clay and shell SC
3
80+
4
80+
5
50
6
35
7
40
8
20
9
15
10
25
Water table at 5.5 feet below ground surface
\ � .J
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/CMJ
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
1 121-200
1 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:
NAME
SIZE LIMITS
Boulder
12 Inches or more
Cobbles
3 to 12 Inches
Coarse Gravel
% to 3 Inches
Fine Gravel
No. 4 sieve to % 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
Greater than 1"
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�