HomeMy WebLinkAboutuniversal"EXHIBIT 3 At!.
Subsurface
Evaluation/Geotechnical
UNIVERSAL
ENGINEERING SCIENCES
Ccoaultents In: eisoinchnlcal Engineering • Threehhoid Inspection Services
Environmental Sciences • Construction Materiels Testing
July 23, 2004
Mr. William Fergen
Sabre Communications Corporation
P.O. Box 658
Sioux City, Iowa 51102-0658
Reference: Geotechnical Exploration Summary
125-Foot Self -Supported Tower
City of Miami Fire Station #11
5920 West Flagier, Miami, Florida
UES Project No. 67905-001-01
UES Report No. 9217
Dear Mr. Fergen:
Exploration
Offices In:
• Orlando
• Gainesville
• Ft. Myera
• Merritt Island
• St. Augustine
• Daytona Beach
• West Palm Beach
• ThIlahaeaee
• Jacksonville
• DeBary
Universal Engineering Sciences, Inc. (UES) has completed a subsurface eval
above -referenced site. The purpose of the exploration was to complete one
Standard Penetration Test (SPT) boring as close as possible to the proposed t
UES was able to provide general site Information and selected geotechnical sol
for later foundation design calculations.
PROJECT PURPOSE AND SCOPE OF SERVICES
This report presents the data from one test boring completed at the above -refer
order to determine the soli profile at a proposed self -supported tower. UES un
subsurface Information will be used to design and construct the foundations for a p
supported tower,
UES has provided the folldwing services in order to achieve the preceding obje
• Performed one Standard Penetration Test (SPT) boring at the location
marked by Sabre Communications Corporation to a depth of 50 feet.
• Visually classify the retrieved soil samples In our laboratory based upo
Soil Classification System (USCS).
• Measure the depth to existing groundwater upon initial encounter and
average wet seasonal high groundwater level.
ation at the
0-foot deep
er location.
parameters
nced site in
rstands the
oposed seff-
we:
rovided and
the Unified
estimate an
• Prepare a brief report which summarizes the methods used In s mpiing and
encountered subsurface conditions, Including the estimated soil parameters based
on a visual examination of the retrieved soil samples.
Page 1 of 5 Pages
1818 7th Avenue North • Unit 1 • Lake Worth, Florida 33461 • (561) 540-6200 • Fax (561) 540-6242
UES Project No.: 87905-001-01
UES Report No.: 9217
SUBSURFACE EXPLORATION
The subsurface conditions at the sign base were explored with one 50-foot deep Standard
Penetration Test (SPT) soil boring. The boring was performed near the field staked location,
in an accessible area as designated by Sabre Communications Corporation.
The SPT boring was performed in general accordance with the procedures outlined by ASTM
D-1586; however, continuous sampling was used to detect slight variations in the soil profile
at shallow depths. The base procedure for the SPT Is as follows: A standard split barrel
sampler is driven Into the soil by a 140-pound hammer falling 30 inches. The number of blows
required to drive the sampler 1 foot, after seating 6 inches, is designated the penetration
resistance, or N-value, this value is an index to soil strength and consistency.
LABORATORY SERVICES
The soil samples recovered from the soil test boring were returned to our laboratory and a
member of our geotechnical engineering staff visually examined and reviewed the field
descriptions. The samples were classified in general accordance with American Society of
Testing and Materials (ASTM) method D-2488, titled "Description and Identification of Soils"
(Visual -Manual Procedure). See Appendix A: Boring Log for further results.
SUBSURFACE CONDITIONS
The results of the field exploration, together with pertinent information obtained from the SPT
boring, such as the soil profile, penetration resistance and groundwater level are shown on the
boring log Included in Appendix A. The Key to Boring Logs/Soil Classification Chart is also
Included in Appendix A. The soil profiles were prepared from the field log after the recovered
sail samples were examined by a member of our geotechnical engineering staff. The
stratification lines shown op the boring log represent approximate boundaries between soil
types, and may not depict"exact subsurface soil conditions. The actual soil boundaries may
be more transitional than depicted. A generalized profile of the soils encountered along with
the estimated unit weights are presented in Table I. For a more detailed profile, please refer
to the attached boring log.
Page 2 of 5 Pages
UES Project No.: 67905-001-01
UES Report No.: 9217
TABLE 1: GENERAL SOIL PROFILE WITH UNIT WEIGHTS
Typical
Depth
Below
Grade* (feet)
Soil Description
Estimated
Unit Weight
(pcf)
''sat
' " ub
0 - 4
Loose, brown sand with traces of limestone [SP]
115
53
4 - 8
Loose, tan sand with limestone [SP]
115
53
8 - 25
Very loose to medium dense, tan to brown sand with
traces of limestone [SP]
117
55
r 25 - 45
Medium dense, gray sand [SP]
117
55
45 - 50**
Medium dense to very dense, greenish gray to tan sand
with limestone [SP]
119
57
NOTE: * Depth measured In feet below existing grade
** Boring Termination
Depth to existing groundwater was measured to be approximately 7.5 feet below the existing
land surface (bis) at the time this exploration was completed. The best estimate for an average
wet seasonal high groundwater table is approximately 5.5 feet bis. Fluctuations in the
groundwater table level should be anticipated throughout the year due to variations in rainfall,
surface runoff, changes in the established drainage characteristics/features and other factors.
ENGLNEERING EVALUATION
The recommendations included herein are based on the project characteristics described to
us, results of our field exploration and our experience with similar projects. Table 2 presents
the recommended soil parameters for the boring location.
It is our understanding that the foundation system will be designed by others. The sel-
supported tower foundations should be designed using the soil parameters provided below In
Table 2. The designs should incorporate factors of safety in the loading considerations due to
axial compression Toads, and lateral and torsional loads created by wind action.
Page 3 of 5 Pages
UES Project No.: 67905-001-01
UES Report No.: 9217
Construction will most likely require the use of "wet -hole" methods due to the encountered soils
and relatively shallow groundwater. Drilling procedures that include a drill slurry to maintain the
open hole will most likely be required.
TABLE 2: RECOMMENDED SOIL DESIGN PARAMETERS
Layer
Depth
(Feet)
SPT "N"
Range
Estimated
Angle of
Internal
Friction
(Degrees)
Cohesion
(PSF)
Active
Earth
Pressure
Coefficient
(Ka)
Passive
Earth
Pressure
Coefficient
(Kp)
Tip
Resistance
(ksf)
Estimated
Unit
Friction
Values
(ksf)
0-4
9-8
30
0
•0.33 ,
3.0
0
0
4-8
5-9
30
0
0.33
3.0
1
0.5
8-25
4-21
31
0
0.32
3.1
2
0.5
25 - 45
12 - 13
31
0
0.32
3.1
5
0.6
45 - 50
19 - 55
34
0
0.28
3.5
7
0.7
Note: 1, Tip resistance values include a safety of factor of 3 and are computed at the middle of the soil
layer
2. Friction values calculated using Coyle/Castello method.
LIMITATIONS
During the early stages of most construction projects, geotechnical issues not addressed in this
report may arise. Because of the natural limitations inherent in working with the subsurface,
it is not possible for a geotechnical engineer to predict and address all possible problems. An
Association of Engineering Firms' Practicing in the Geosciences (ASFE) publication, "important
Information About Your GeQtechnical Engineering Report' appears In Appendix B, and will help
explain the nature of your"geotechnical issues.
Further, we present documents in Appendix B: Constraints and Restrictions, to bring to your
attention the potential concerns and the basic limitations of a typical geotechnical report.
Page 4 of 5 Pages