RC-12-21-3146 Engineering Ltr 10560 NE 2 CtGEOTECHNICAL I ENVIRONMENTAL I MATERIALS TESTING I ASBESTOS I ROOF TESTING I INSPECTION SERVICES I DRILLING SERVICES
I= DYNATECH ENGINEERING CORP
DEC
`, _•;, WWW.DYNATECHENGINEERING.COM
Miami, September 14, 2022
Mr, Juan Vazquez
PINECREST GROUP, INC.
18672 SW 93`d Court
Cutler Bay, FL 33157
Re: Proposed Addition @
10560 NE 2nd Court
Miami Shores, FL 33138
Dear Mr. Vazquez:
60, -- 12 -2 l - -_:�14 �,
Pursuant to your request, DYNATECH ENGINEERING CORP. (DEC) completed a Subsoil
Investigation on September 14, 2022 at the above referenced project. The purpose of our investigation
was to help determine the subsoil conditions relative to foundation design of the proposed structures.
A total of (2) standard penetration boring tests were performed according to ASTM-D 1586 down to an
average depth of 15' below existing ground surface at the locations shown on the attached sketch only.
The following graph was developed as a general condition below existing ground surface at the time of
drilling for the subject site (Subsoil conditions are non -homogenous, refer to field boring logs for exact
locations and soil description. Average depths are approximate and will vary in the field):
Average Depth
From
To
Description
0'-0-
0'-6"
Topsoil
0'-6"
2'-0"
Gray medium sand w/rock fragments
2'-0"
8'-0"
Tan medium sand
8'-0"
15'-0"
Tan sandy limerock
Groundwater was measured immediately at the completion of each boring and was found at an average
depth of approximately 7' below existing ground surface at the time of drilling. This immediate depth to
groundwater level should not be relied upon alone for project design considerations. Existing ground
surface elevation was not provided to us at the time of drilling. Design engineers must verify existing
ground elevations as well as FEMA Flood and County highest and lowest groundwater elevation for their
design. Fluctuation in water level is anticipated due to seasonal variations and run off as well as varying
ground elevations construction dewatering and pumping activities in the area, king tides, flash flooding,
storm surge and global warming. Site contractor must familiarize himself with site conditions in the event
groundwater controls and dewatering is needed during construction. Surface flooding may result under
hurricane conditions and should be taken into consideration in the design of the project. The contractor
shall monitor and make sure that groundwater levels on adjacent properties are not adversely impacted
due to the contractors dewatering activities. Specialty groundwater and water proofing contractors shall
be consulted for all work below the.groundwater level. All dewatering volume & effluent discharge must
meet local, State & Federal requirements.
or-
750 WEST 84TH STREET, HIALEAH, FL 33014 PHONE (305) 828-7499 FAX (305) 828-9598 EMAIL:INFOODYNATECHENGINEERING.COM EG
Re: 10560 NE 2" d Court, Miami Shores; FL
Based on our understanding of the proposed structure and our field boring logs; the following are our
recommendations for foundations design.
A- Strip the entire building construction areas of all topsoil, grass, tree stumps and construction debris
down to clean granular material wherever encountered (see field boring logs). Any underground
structures, former pools, septic tanks, utilities, root systems and drainages trenches, etc ... must be
removed in their entirety from beneath the proposed construction area. All roots greater than one inch
in diameter, or a high concentration of smaller diameter roots, must be removed prior to back filling.
Clean fill can be stored for reuse pursuant to our approval. The actual depth of stripping MUST be
determined in the field during the clearing and excavations.
B- Compact all construction areas with a heavy self-propelled roller to a rninirnum of 95% of ASTM
D-1557 but not less than 10 passes in each direction. Localized areas of loose materials, if present, will
become evident during site clearing, grubbing and proof rolling, and must be removed prior to filling
operations. Backfill construction areas to required elevation using clean granular homogenous material
placed in lifts not to exceed 12 inches in thickness and compact as indicated above. In areas not
accessible for compaction, flowable fill shall be used.
C- Excavate footing areas only to proper depth and recompact as indicated above. Footings must be cast
as soon as possible after excavation to minimize potential damage to bearing soils from exposure to
the element, construction activities and soil creep.
D- Care should be taken not use vibration in case of existing structures in the vicinity of the
construction area. [f vibration cannot be used for corpaction, static compaction may be applied.
However, in this case, the compacted layer should not exceed 6 inches in thickness.
[:;- All construction fill material above the water table shall consist of clean granular homogenous soil,
free of organics or other deleterious material, and shall contain no more than 12 percent fines passing
a U.S, standard No. 200 sieve and have a Unified Soil Classification System (USCS) designation of
GP, GW, GP -GM, GW-GM, SP, or SW. No particle size greater than 3 inches shall be in the top 12
inches ofthe building pad.
Fill material below the water table shall consist of washed free draining gravel to about 12 inches above
the water table. (ie: Ballast rock FDOT No. 57 stone or equivalent) unless dewatering is employed.
When dewatering is employed, fill material shall consist of clean, granular homogenous soil, free of
organics or other deleterious material, and shall contain no more than 5 percent fines passing a US
standard No. 200 sieve.
F- Verify all compaction efforts by taking an adequate number of field density tests in each layer of
compacted material and in each footing pad but no less than 1 test every 2500 square feet.
G- Representative samples of the on -site and proposed fill material shall be collected and tested to
detennine the classification and compaction characteristics prior to use.
1-1- All Geotechnical work must be performed under the supervision of our geotechnical engineer
or his representative to verify compliance with our specifications and the Florida Building Code.
I- In case of existing structures, existing footings new foundations and proposed drainage lines,
provisions shall be made by the structural engineer, the civil engineer; and site contractor to protect all
footings from future erosion, undermining and exposure. The geotechnical engineer shall be notified
of these conditions to evaluate the applicability of his recommendations.
The above foundation recommendations being achieved and verified; it is our opinion that the proposed structures
be designed for a shallow foundation system with a net static permissible soil bearing pressure not to exceed 2500
P.S.F. All footings bottom shall be based at a depth of not less than 12" below the lowest adjacent grade. Design
computations for thickness shall utilize a modulus of subgrade reaction value of 250 pct.
750 WEST B4TH STREET, HIALEAH, FL 33014 PHONE (305) 828 -749 9 FAX (305) 828-959B EMAIL: INFOODYNATECHENGINEERING.COM
Re: 10560 NE 211d Court, Miami Shores, FL
Slabs may be designed as slabs on grade and must be provided with proper expansion and control joints
as designed by the structural engineer.
The following soil parameters shall be used for retaining wall designs:
- Soil unit weight moist: 115 pef. Submerged: 53 pcf.
- Angle of internal friction: 30'
- Earth pressure coefficient Ka: 0.33; Kp: 3.0
- Angle of wall friction: 30' for steel piles, 20' for concrete or brick walls; 15' uncoated steel.
Excavations shall not extend within 1 foot of the angle of repose, next to existing footings or structures,
unless underpinned. Trenching shall be in compliance with the Florida Building Code, OSHA and Trench
Safety Act. Shorings shall be designed and inspected by Florida licensed professional engineer.
Excavation contractor must make provisions for hard excavation conditions. Particular attention should
be paid to any deep excavations and their potential impacts on adjacent structures.
Provisions shall be made by the architect, engineer of record and contractor to address differential
vibration / dynamic loading; settlements when tying in new to existing structures. Mixing of different
foundation types shall not be used unless provided with expansion joints to address differential settlements
and vibration transfer.
Also note that as a common engineering practice for existing and new construction; outside ground
surfaces must be sloped away from the structure as to avoid water accumulation and ponding. Rain gutters
shall be installed and all rain water shall be discharged over splash guards a minimum of 5 feet away from
building foundations. Verify all water, sewer, plumbing, sprinkler and drainage lines are properly
functioning with no leaks in the vicinity of the foundations.
An arborist must be consulted prior to any land clearing to verify compliance with local codes.
Detailed settlement analysis was beyond the scope of this report. However, we have compared the field
test data obtained in this exploration with our experience with structures similar to those proposed for this
report. The estimated magnitude of these settlements is less than inch differential and less than
1-inch total settlements. Due to the granular nature of the subsurface materials, the foundation settlements
should occur as the loads are applied and should be virtually negligible by the end of the building shell
completion.
If dynamic loading is proposed (ie: parking garage, etc...) this condition MUST be brought to our attention
to re-evaluate the applicability of our recommendations.
The site may have been developed in the past. The exact extent of this development is unknown; therefore,
any changes in the subsurface conditions must be brought to our attention for evaluation and
recommendation. Any voids created by the removal of former structures must be properly backfilled as
described in our foundation recommendations.
750 WEST 84TH STREET HIALEAH, FL 33014 PHONE (305) 828-7499 FAX (305) 828-9598 EMAIL:INFOODYNATECHENGINEERING.COM WE IC
Re. 10560 NE 2"d Court, Miami Shores, FL
This report was prepared in compliance with the 2020 Florida Building Code, 7111 edition. Site elevations
were not provided to us for the test locations. Depths reported on the field boring logs represent the depth
below existing ground surface as they existed on the date of drilling. In the event of subsequent filling,
excavations or site work, the reported depths must be adjusted to represent proper depths.
The boring log (s) attached present (s) a detailed description of the soils encountered at test location (s).
The soil stratification shown on the boring log (s) is based on the examination of the recovered soil samples
and interpretation of the driller's field log (s). It indicates only the approximate boundaries between soil
types. The actual transitions between adjacent soil types may be gradual. Regardless of the thoroughness
of a geotechnical exploration there is always the possibility that conditions may be different from those of
the test locations; therefore, DYNATECH ENGINEERING CORP. does not guarantee any subsoil
conditions between the bore test holes. In accepting and using this report the client understands and accepts
that all data from the borings are strictly for foundation analysis only and are not to be used for excavation
or back .filling estimates and pricing. Owner and site contractor must familiarize themselves with site
conditions prior to bidding. Client recognizes that actual conditions in areas not tested by DEC may differ
from those anticipated in DEC's report. Client understands and accepts that this can significantly increase
the cost of construction for its future projects. Client agrees that DEC shall not be responsible or liable for
any variations in the actual conditions of areas not tested by DEC. This report is not a Phase I and/or Phase
II Environmental Site Assessments. As a mutual protection to clients, the public and ourselves, all reports
are submitted as the confidential property of clients, and authorization for publication of statements,
conclusions or extracts from or regarding our reports is reserved pending our written approval. The scope
of services performed in the execution of this investigation may not be appropriate to satisfy the needs of
other users, and use or re -use of this document or the findings, conclusions, or recommendations is at the
risk of said user. Said user must contact DEC in writing to verify applicability of this report for their use.
All work must be conducted under the supervision of our geotechnical engineer. The discovery of any site
or subsurface conditions during construction which deviate from the information obtained from our
subsoil investigation is always likely and should be reported to us for our evaluation. All work shall be
conducted in compliance with the Florida Building Code FBC and OSHA workers protection rules and
all applicable Federal, State, County and City rules and regulations. In the event, changes, challenges and
other value engineering opportunities occur without our knowledge, our recommendations may become
compromised and geotechnical related issues may be misconstrued. Therefore, all geotechnical work shall
be performed under our supervision to verify compliance with the intent of our recommendations.
It has been a pleasure working with you and look forward to do so in the near future.
Sincerely y yours,
�-ani,
E11���No.3958�4TI-1
DYNATECI-I ENGINEERING CORP. - ' -
Florida Reg. No. 39584 = .a'; STATE OF •r
Special Inspector No. 757 ;�0,�;••.t RSpA..�4`
Certificate of Authorization No.: CA 5491 �`'�'SS/�NALE�G`'���.
►I
THIS ITEM HAS I3EEN DIGITALLY
SIGNED AND SEALED
BY WISSANI SAND NAAIIAN'I, P.E. ON
TI IE DATE ADIACFNTTO TIIE SEAL.
PRINTED COPIES OF THIS DOCUMENT
ARE NOT CONSIDERED SIGNED AND
SEALED AND THE SIGNATURE MUST BE
VERIP' rD ON .ANY ELECTRONIC COPIES.
750 WEST 84TH STREET. HIALEAH, FL 33014 PHONE (305) 828-7499 FAX (305) B28-9598 EMAIL:INFOODYNATECHENGINEER ING.COM t`
li,foEST BORING FIELD I.�ZG-,
DYNATECH
ENGINEERING CORP.
TEST BORING FIELD LOG
CLIENT : PINECREST GROUP, INC.
PROJECT Proposed Addition @
ADDRESS 10560 NE 2nd Court, Miami Shores, FL
LOCATION See attached sketch
DATE: September 14, 2022
HOLE NO.: B-1
DRILLER: JA / NV
Depth
From - To
DESCRIPTION OF MATERIALS
Depth
From -
To
HAMMER
BLOWS ON
SAMPLER
"N"
0'-0" to V-6"
1'-6" to 4'-O"
4'-0" to T-0"
T-0" to 8'-0"
8'-0" to 8'-6"
8'-6" to 15'-V
GRAY SAND WITH ROCK FRAGMENTS
WHITE MEDIUM SAND
LIGHT TAN SAND
TAN SAND
TAN SLIGHTLY SILTY SAND
TAN SANDY LIMEROCK
2
Hand
H
4
4 5
4 6
9
6
6 4
4 7
8
8
8 6
5 5
11
10
A
A
12
A
A
14
A
A
16
A
A
18
20
22
24
26
28
30
32
34
36
38
Water Level: 7' Below Existing Land Surface at time of drilling As a mutual protection to clients, the public and ourselves, all reports are submitted as the
confidential property of clients, and authorization for publication of statement conclusions or extracts from or reearding our reports is reserved pending on our written
approval. I I.A. I land Auger; A: Hollow Stem Auger; R: Refusal., DRILLING: S: Soft, M: Medium, H: Hand, R: Refusal, V.H.: Very I lard.
5
750 WEST 84TH STREET, HIALEAH. FL 33014 PHONE (305) 828-7499 FAX (305) 828-9598 EMAIL:INFOODYNATECHENGINEERING COM $i'
DYNATECH ENGINEERING CORP
TEST BORING FIELD LOG
CLIENT
PINECREST GROUP, INC.
DATE: September 14, 2022
PROJECT
Proposed Addition @
HOLE NO.: B-2
ADDRESS
10560 NE 2nd COUrt, Miami Shores, FL
DRILLER: JA / NV
LOCATION
See attached sketch
Depth
Depth
HAMMER
From - To
DESCRIPTION OF MATERIALS
From - BLOWS ON "N"
TO
SAMPLER
2
Hand H
4
4 4 7
0'-0" to 0'-6"
TOPSOIL AND GRASS
3 5
6
5 4 8
0'-6" to 2'-0"
GRAY SAND WITH ROCK FRAGMENTS
4 7
8
6 8 14
2'-0" to 3'-6"
WHITE MEDIUM SAND
6 8
10
A A
3'-6" to 5'-6"
LIGHT TAN SAND
12
A A
5'-6" to 8'-0''
'FAN SAND
14
A A
8%0" to 8'-6"
TAN SLIGHTLY SILTY SAND
16
A A
8'-6" to 15'-0"
TAN SANDY LIMEROCK
18
20
22
24
26
28
30
32
34
36
38
Below Existing Land Surface at time of drilling As a mutual protection to clients, the public and ourselves, all reports are submitted as the
Water Level: 7'
confidential property of
clients, and authorization for publication of statement conclusions or extracts from or regarding our reports is reserved pending on our written
approval. I1.A,: Hand Au.-er; A: Hollow Stem Auger; R: Refusal., DRILLING: S: Soft, M: Medium. H: [land, R:
Ref, sal, V.I-1.. Ven• Hard.
6
750 WEST 84TH STREET, HIALEAH. FL 33014 PHONE (305) 828-7499 FAX (305) 828-9598 EMAIL:INFOODYNATECHENGINEERING.COM C
1�-
SITE PLAN
GENERAL (VOTES
Soil borings on unmarked vacant property should be considered preliminary with further
boring (s) to be drilled after building pad (s) are staked out.
Soil borings on existing structures that are to be demolished should be considered
preliminary and additional borings should be performed after the structure (s) has been
demolished and proposed new building staked out.
As mutual protection to clients, the public and ourselves, all reports are submitted as
confidential property of clients. Authorization for publication statement, conclusions,
extracts from or regarding our reports is reserved pending our written approval,
KEY CLASSIFICATIONS & 5YMBOL5
CORRELATION OF PENETRATION RESISTANCE WITH
RELATIVE DENSITY AND CONSISTENCY
CONE - --- - —.
PENETRATION STANDARD RELATIVE
TESTS PENETRATION DENSITY
SANDS
SILTS &
CLAY
0-16
17-40
41-80
81-120
Over 120
0-3
4-9
10-17
18-31
32-60
Over 60
(Blows/Ft.)
0-4
5-10
11-20
21-30
31-50
0-2
3-4
5-8
9-15
16-30
31-50
Very Loose
Loose
Firm
Very Firm-�
Dense
Very Loose
Soft
Firm
Stiff
Very Stiff
Hard _ ....
_ PARTICLE SIZE -
BOULDERS -- 12 in. -- -
COBBLE y 3 in, to 1 in. y
GRAVEL 4.76 mm to 3 in.
SAND_ 0.07 mm to 4.67 mm
w SILT _ J i 0.005 mm to 0.074 nim
CLAY < 0.005 mm ^�
MODIFIERS -
5%-10",,In Slightly Silty or Clayey
10%-30% Siltyor Clayey
_ --( �- —
30%_50 j Very Silty or Very Ciaycy
Slight Trace
6%10% Trace
11%-20^� Little -� _ ' ' •• _...
21%-35:7� I Some - -- — — -
>35% { Some More.
ROCK HARDNESS DESCRIPTION _
Soft core. Crumbles when _handled. -� —
Medium EtRock
an break with your hands
Moderate { Thin edges or rock core. Can be broken with fingers.
Hard
Hard �Rock
dges or rock core. Can be broken with fingers.
Very Hard ore. Rings when struck with hammer (cherts).