HomeMy WebLinkAboutWESTBURY PUD, SECOND FILING - FINAL - 11-94B - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTLOG OF BORING No. 9
Page 1 of 1
CLIENT
ARCHITECT/ENGINEER
Linder Real Estate
Cityscape Urban Design \ Stewart & Associates
SITE South Shields Street
PROJECT
Fort Collins, Colorado
Westbury P.U.D. Filing Two
SAMPLES
TESTS
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c 11
5
z
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s
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FIT T -Fat clay
CH
1
SS
12"
15 1
8
Brown/red, moist
2 1
SS 1
12"1
15
3.0
SANDY LEAN CLAY
Tan, moist, stiff
WEATHERED SANDSTONE/
CLAYSTONE
Tan/gray, moist, moderately hard
BOTTOM OF BORING
5080.0
5
507� 10
12" 1 11 1 1
41SS112"1 19 1 12
THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES
BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL.
WATER LEVEL OBSERVATIONS
Empire Laboratories
Incorporated
Division of Terracon
BORING STARTED 3-3-95
WL
g None W.D.=
BORING COMPLETED 3-3-95
wL
RIG CME-55
FOREMAN DML
a I
Hole filled in A.B.
APPROVED LRS
IJOB # 20955035
LOG OF BORING No. 8
Page 1 of 1
CLIENT
ARCHITECT/ENGINEER
Linder Real Estate
Cityscape Urban Design \ Stewart & Associates
SITE South Shields Street
PROJECT
Fort Collins, Colorado
Westbury P.U.D. Filing Two
SAMPLES
TESTS
o
Z Wo
o
000
H~(n
JLL
z
z
H~
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DESCRIPTION
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to
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Approx. Surface Elev.: 5084.0 ft.
a
o
Z
F-
mm
E
oa
ova
�d�
FILL -Fat clay
1
SS
12"
11
15
Brown, moist
SS
12"
7
voo<2
3.0 Composite sample @ 1 to 4 ft. 5081.0
50/31/85
CH
3
BS
SANDY LEAN CLAY
Tan/gray/olive, moist, medium
stiff
5
g.5 5075.5
WEATHERED SANDSTONE/
C AYSTONE 50740
10.0 Tan/gray/olive, moist .10
Moderately hard
BOTTOM OF BORING
M&xy51
5 1 SS 1 12" 1 26 1 13
THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES
BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL.
WATER LEVEL OBSERVATIONS
Empire Laboratories
Incorporated
of Terracon
BORING STARTED 3-3-95
BORING COMPLETED 3-3-95
w►
g None WD•
-
=
RIG CME_;;
FOREMAN DMEL
WL
EDivision
APPROVED LRS
JOB # 20955035
WL
Hole filled in A.B.
LOG OF BORING No. 7
Page
1 of 1
CLIENT
ARCHITECT/ENGINEER
Linder Real Estate
Cityscape Urban Design \ Stewart & Associates
SITE
South Shields Street
PROJECT
Fort Collins, Colorado
Westbury
P.U.D. Filing
Two
SAMPLES
TESTS
Jo
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DESCRIPTION
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WWLL
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Approx. Surface Elev.: 5084.0 ft.
W
o
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o
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0.5
6" TOPSOIL
5083.5
CL
1
SS
12"
19
19
2.0
LEAN CLAY
Brown, moist, very stiff
5082.0
SANDY LEAN CLAY
CL
475
2
ST
4"
16
116
4550
Tan/red, moist, very stiff
4.0
5080.0
3
SS
12"
18
13
WEATHERED CLAYSTONE
5
Tan/olive, moist, moderately hard
6.5
5077.5
4
ST
12"
5
SS
10"
50110
10
C'T AYSTONE
10
Tan/olive, moist, hard
14.5 5069.5
THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES
BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL.
WATER LEVEL OBSERVATIONS BORING STARTED 3-1-95
WL g None w.D- = Empire Laboratories BORING COMPLETED 3-1-95
`A'L 13.0' D.C.I. Incorporated RIG CME-55 FOREMAN DML
wl Water checked 4 days A.B. Division of Terracon APPROVED LRS JOB N 20955035
LOG OF BORING No. 6
Page 1 of 1
CLIENT
ARCHITECT/ENGINEER
Linder Real Estate
Cityscape Urban Design \ Stewart & Associates
SITE South Shields Street
PROJECT
Fort Collins, Colorado
Westbu P.U.D. Filing Two
SAMPLES
TESTS
►-
X
o
0
0
.,
o
-j
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>.
LL
W
N
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DESCRIPTION
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to
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EL
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a
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a
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UMU-
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Approx. Surface Elev.: 5085.5 ft.
W
0
Ln
o
D
Z
>_
W
M
aJ
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o a
ZI—Cn
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" " "
0.5 6" TOPSOIL 5085.0
1:5 LEAN CLAY 5084.0
Brown, moist, stiff
CL
1
SS
12"
13
17
SANDY LEAN CLAY
Tan/red, moist, medium stiff
CL
2
ST
4"
13
107
1800
3
SS
12"
6
18
5
7.5 5078.0
4
ST
12"
15
SW
5
SS
12"
7
16
1
a
SAND WITH GRAVEL
10
1
Red/tan, moist to wet _
Loose to medium dense
6
SS
12"
16
1 22
�?
14.5 5071.0
15
YZ
15.0 WEATHERED CLAYSTONE 5070.5
Tan/olive, moist, soft
BOTTOM OF BORING
THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES
BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL.
WATER LEVEL OBSERVATIONS
Empire Laboratories
Incorporated
Division of Terracon
BORING STARTED 3-1-95
WL
ju None a' D
= 10.3' A.B.
BORING COMPLETED 3-1-95
WL
RIG CME-55
FOREMAN DML
WL
Water checked 4 days A.B.
APPROVED LRS
JOB k 20955035
LOG OF BORING No. 5 Page 1 of 1
CLIENT
Linder Real Estate
ARCHITECT/ENGINEER
Cityscape Urban Design \ Stewart & Associates
SITE South Shields Street
Fort Collins, Colorado
PROJECT
Westbury P.U.D. Filing Two
L�
=
IL
LD
DESCRIPTION
Approx. Surface Elev.: 5092.5 ft.
2
F-
d
o
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}
to
(n
U
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SAMPLES
TESTS
W
m
r
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W
a.
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ow
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0.5 6" TOPSOIL 5092.0
LEAN CLAY
Brown, moist, very stiff to stiff
soluble sulfate
7.5 content at 7' to 8'=0.0022% 5085.0
5
10
15
1
SS
12"
17
18
1950
011AWater
CL
2
ST
4"
20
105
2010
3
SS
12"
8
23
4
ST
12"
22
110
2500
WEATHERED CLAYSTONE
Tan/olive, moist, moderately hard
10.0 5082.5
5
SS
12"
26
13
i
CLAYSTONE
Tan/olive, moist, hard
19.7 5072.8
BOTTOM OF BORING
6
SS
12"
48
13
7
SS
8"
50/8
13
THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES
BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL.
WATER LEVEL OBSERVATIONS
Empire Laboratories
Incorporated
Division of Terrecon
BORING STARTED 3-1-95
WL
Q None W.D.
__ 12,4+ A.B.
BORING COMPLETED 3-1-95
WL
RIG CME-55
FOREMAN DMI,
WL
Water checked 4 days A.B.
APPROVED LRS
JOB a 20955035
LOG OF BORING No. 4
Page 1 of 1
CLIENT
ARCHITECT/ENGINEER
Linder Real Estate
Cityscape Urban Design \ Stewart & Associates
SITE South Shields Street
PROJECT
Fort Collins, Colorado
Westbury P.U.D. Filing Two
SAMPLES
TESTS
\
Y
C7
O
J
O
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Y
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Approx. Surface Elev.: 5089.0 ft.
o
:3
z
M
to m
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o o-
5 N D.
(n D. D-
CL
1
SS
12"
11
16
r_.FAN CLAY
Brown, moist, stiff
3.0 5086.0
135
CL
2
ST
4"
14
113
3740
3
SS
12"
li
16
SANDY LEAN CLAY
5
Red/tan, moist to wet
Stiff to medium stiff
Water soluble sulfate
4
ST
12"
14
115
3860
content at 3' to 4'=0.0007 %
5
SS
12"
7
18
10
i
6
SS
12"
6
24
15.0 5074.0
15
BOTTOM OF BORING
THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES
BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL.
WATER LEVEL OBSERVATIONS
Empire Laboratories
Incorporated
Division of Te((acon
BORING STARTED 3-1-95
WL
g None W.D.
= 10.67 A.B.
BORING COMPLETED 3-1-95
WL
RIG CME-55
FOREMAN DML
WL
Water checked 4 days A.B.
APPROVED LRS
JOB N 20955035
14
LOG OF BORING No. 3 Page 1 of 1
CLIENT
ARCHITECT/ENGINEER
Linder Real Estate
Cityscape Urban Design \ Stewart & Associates
SITE South Shields Street
PROJECT
Fort Collins, Colorado
Westbury P.U.D. Filing Two
SAMPLES
TESTS
W
m
E
m
z
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a.
>-
F_
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H
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H
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DESCRIPTION
Approx. Surface Elev.: 5099.5 ft.
LL
=
N
0-
W
o
O
}
O
W
U
N
^ "^"
0.5 6" TOPSOIL 5099.0
T_.F_AN CLAY
Tan, moist, medium stiff to stiff
1
SS
12"
8
22
48/29/86
CL
2
BS
3.0 Composite sample @ 1 to 3 ft. 5096.5
CL
3
ST
4"
13
109
2180
SANDY LEAN CLAY
4
SS
12"
4
14
Tan/red, moist
Medium stiff to stiff
5
Gravelly below 7 feet
5
ST
12"
16
113
1670
6
SS
12"
13
8
9.0 5090.5
WEATHERED L�TONE/
SANDSTONE
10
11.0 Tan/olive, moist, moderately hard 5088.5
SANDSTONE/CLAYSTONE
Tan/olive, moist, hard
7
SS
8"
50/8
9
14.7 5084.8
BOTTOM OF BORING
THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES
BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL.
WATER LEVEL OBSERVATIONS
BORING STARTED 3-1-95
Empire Laboratories
BORING COMPLETED 3-1=95
wL
g None W D
t
Incorporated
RIG CME-55
FOREMAN DML
wL
13.1' D.C.I.
Division of Terrecon
APPROVED LRS
JOB # 209�935 ..
vvl.
Water checked 4 days A.B.
LOG OF BORING No. 2
Page 1 of 1
CLIENT
ARCHITECT/ENGINEER
Linder Real Estate
Cityscape Urban Design \ Stewart & Associates
SITE South Shields Street
PROJECT
Fort Collins, Colorado
Westbury P.U.D. Filing Two
SAMPLES
TESTS
N
}
S co
U
DESCRIPTION
}
w
z�
M
z
H�
M
y
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fn
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U
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Approx. Surface Elev.: 5103.5 ft.
W
o
w
:3
M
z
}
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W
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cn fa
O
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D:U
co-
zhcn
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0.5 6" TOPSOIL 5103.0
1
SS
12"
12
21
a
f.
's
!' >
';..._.
SANDY LEAN CLAY
625
CL
2
ST
4"
12
111
8130
Tan, moist, stiff to very stiff
3
SS
12"
16
12
�g
5
7.5 5096.0
4
ST
12"
11
113
5580
4
WEATHERED CLAYSTONE/
SANDSTONE
5
SS
12"
15
15
Tan/olive, moist
Soft to moderately hard
10
10.5 5093.0
SANDSTONE/CLAYSTONE
Tan/olive, moist, hard
14.5 5089.0
BOTTOM OF BORING
6
SS
6"/
•
i
i
9
r
s
t
THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES
BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL.
3 WATER LEVEL OBSERVATIONS
BORING STARTED 3-1-95
Empire Laboratories
WL
g None W.D.
= None A.B.
BORING COMPLETED 3-1-95
Incorporated
Division of Terracon
WL
RIG CME-55
FOREMAN DMIL
WL
x_
Water checked 4 days A.B.
APPROVED LRS
JOB x 20955035
r,
LOG OF BORING No. 1 Page 1 of 1
CLIENT
Linder Real Estate
ARCHITECT/ENGINEER
Cityscape Urban Design \ Stewart & Associates
SITE South Shields Street
Fort Collins, Colorado
PROJECT
Westbu P.U.D. Filing Two
0
H
_
0-
Cc
LD
DESCRIPTION
-
Approx. Surface Elev.: 5103.0 ft.
�
S
F—
4_
o
o
en
>
O
U
�
SAMPLES
TESTS
W
m
E
z
W
G.
w
>
O
U
W.
�
zLL
: Cn
3
F— O
(n CO
�
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H
E
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w
O
} LL
O a
o
W
H�
Z Z
ow
UQ� LL
m cn a.
M
J (n
J fA
W W LL.
N a. a
AAAAA
0.5 6" TOPSOIL 5102.5
LEAN CLAY
Brown, moist, very stiff
3.0 5100.0
5
10
15
CL
1
SS
12"
17
17
970
CLAYEY SAND WITH GRAVEL
Red/tan, moist, dense
7.5 5095.5
4"
SC
3
SS
IT,
44
8
4
ST
12"
14
108
2320
WEATHERED CLAYSTONE
Tan/gold, moist, moderately hard
9.5 5093.5
5
SS
12"
34
15
CLAYSTONE
Tan/gold, moist, hard
19.5 5083-
6
SS
8"
50/8
14
4
BOTTOM OF BORING
THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES
BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL.
WATER LEVEL OBSERVATIONS
Empire Laboratories
Incorporated
Division of Terracon
BORING STARTED 3-1-95
Wil
g None W.D.
t
BORING COMPLETED 3-1-95
wL
12.4' D.C.I.
RIG CME-55
FOREMAN DMI,
wL
Water checked 5 days A.B.
APPROVED LRS
I JOB s 20955035
1 N a K
— r • s. °' N �
a � N
a M I
N �
1 J u1 r N
0
V 3 M
N N
M
m
N
o N N
i
to 1
i
V
J�� c
�P
Qv 3
e 1 �
FIGURE 1. SITE PLAN O��N
WESTBURY P.U.D. FILING TWO
FORT COLLINS, COLORADO
ELI. PROJECT No. 209,55035 scarf r' =zoo'
Empire Laboratories, Inc.
A Division of The Terracon Companies, Inc.
N
I ]
1]
Geotechnical Engineering Exploration
Linder Real Estate
ELI Project No. 20955035
Terracon
This report is for the exclusive purpose of providing geotechnical engineering and/or testing
information and recommendations. The scope of services for this project does not include,
either specifically or by implication, any. environmental assessment of the site or
identification of contaminated or hazardous materials or conditions. If the owner is
concerned about the potential for such contamination, other studies should be undertaken.
20
Geotechnical Engineering Exploration
Linder Real Estate
ELI Project No. 20955035
Terracon
• Corrosion Protection: Results of soluble sulfate testing indicate that ASTM Type 1-11
Portland cement is suitable for all concrete on and below grade. Foundation
concrete should be designed in accordance with the provisions of the ACI Design
Manual, Section 318, Chapter 4.
GENERAL COMMENTS
It is recommended that the Geotechnical Engineer be retained to provide a general review
of final design plans and specifications in order to confirm that grading and foundation
recommendations have been interpreted and implemented. In the event that any changes
of the proposed project are planned, the conclusions and recommendations contained in this
report should be reviewed and the report modified or supplemented as necessary.
The Geotechnical Engineer should also be retained to provide services during excavation,
grading, foundation and construction phases of the work. Observation of footing and pier
excavations should be performed prior to placement of reinforcing and concrete to confirm
that satisfactory bearing materials are present and is considered a necessary part of
continuing geotechnical engineering services for the project. Construction testing, including
field and laboratory evaluation of fill, backfill, pavement materials, concrete and steel should
be performed to determine whether applicable project requirements have been met. It
would be logical for Empire Laboratories, Inc. to provide these additional services for
continuing from design through construction and to determine the consistency of field
conditions with those data used in our analyses.
The analyses and recommendations in this report are based in part upon data obtained from
the field exploration. The nature and extent of variations beyond the location of test
borings may not become evident until construction. If variations then appear evident, it
may be necessary to re-evaluate the recommendations of this report.
Our professional services were performed using that degree of care and skill ordinarily
exercised, under similar circumstances, by reputable geotechnical engineers practicing in
this or similar localities. No warranty, express or implied, is made. We prepared the report
as an aid in design of the proposed project. This report is not a bidding document. Any
contractor reviewing this report must draw his own conclusions regarding site conditions
and specific construction techniques to be used on this project.
19
Geotechnical Engineering Exploration
Linder Real Estate
ELI Project No. 20955035
Terracon
2. In areas where sidewalks or paving do not immediately adjoin buildings, we
recommend that protective slopes be provided with a minimum grade of
approximately 10 percent for at least 10 feet from perimeter walls. Backfill
against footings, exterior walls, and in utility and sprinkler line trenches
should be well compacted and free of all construction debris to reduce the
possibility of moisture infiltration.
3. Downspouts, roof drains or scuppers should discharge into splash blocks or
extensions when the ground surface beneath such features is not protected
by exterior slabs or paving.
4. Sprinkler systems should not be installed within 5 feet of foundation walls.
Landscaped irrigation adjacent to the foundation system should be minimized
or eliminated.
Additional Design and Construction Considerations:
• Exterior Slab Design and Construction: Exterior slabs -on -grade, exterior architectural
features, and utilities founded on, or in backfill may experience some movement due
to the volume change of the backfill. Potential movement could be reduced by:
• minimizing moisture increases in the backfill
• controlling moisture -density during placement of backfill
• using designs which allow vertical movement between the exterior
features and adjoining structural elements
• placing effective control joints on.relatively close centers
• allowing vertical movements inutility connections
• Underground Utility Systems: All piping should be adequately bedded for proper load
distribution. It is suggested that clean, graded gravel compacted to 80 percent of
Relative Density ASTM D4253 be used as bedding below the pipe. Where utilities
are excavated below groundwater, temporary dewatering will be required during
excavation, pipe placement and backfilling operations for proper construction. Utility
trenches should be excavated on safe and stable slopes in accordance with OSHA
regulations as discussed above. Backfill should consist of the on -site sandy lean
clay. The pipe backfill should be compacted to a minimum of 95 percent of
Standard Proctor Density ASTM D698.
18
Geotechnical Engineering Exploration Terracon
Linder Real Estate
ELI Project No. 20955035
J 4. If a well defined maximum density curve cannot be generated by impact
compaction in the laboratory for any fill type, engineered fill should be
compacted to a minimum of 80 percent relative density by determined by
JASTM D4253 D4254.
5. Clay soils placed beneath pavements should be compacted within a moisture
content range of 2 percent below to 2 percent above optimum. All other clay
fill and backfill should be compacted within a moisture content range of
optimum to 2 percent optimum. Imported granular soils should be compacted
within a moisture range of 3 percent below to 3 percent above optimum.
• Compliance: Performance of slabs -on -grade, foundations and pavement elements
supported on compacted fills or prepared subgrade depend upon compliance with
"Earthwork" recommendations. To assess compliance, observation and testing
should be performed under the direction of the geotechnical engineer.
• Excavation and Trench Construction: Excavations into the on -site soils will
encounter a variety of conditions. Excavations into the clays and bedrock can be
expected to stand on relatively steep temporary slopes during construction.
However, the granular soils may cave and groundwater may also be encountered.
The individual contractor(s) should be made responsible for designing and
constructing stable, temporary excavations as required to maintain stability of both
the excavation sides and bottom. All excavations should be sloped or shored in the
interest,of safety following local, and federal regulations, including current OSHA
excavation and trench safety standards.
Drainage:
• Surface Drainage:
1. Positive drainage should be provided during construction and maintained
throughout the life of the proposed construction. Infiltration of water into
utility or foundation excavations must be prevented during construction.
Planters and other surface features which could retain water in areas adjacent
to the building or pavements should be sealed or eliminated.
J
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Percent fines by weight
Gradation (ASTM C136)
6.. ......................................... 100
3.. ....................................... 70-100
No. 4 Sieve .................................. 50-80
No. 200 Sieve .............................. 70 (max)
• Liquid Limit .......... 36 (max)
• Plasticity Index ......................... 20 (max)
• Minimum R-value (in paved areas) 6.5
4. Aggregate base should conform to Colorado Department of Transportation
Class 5 or 6 specifications. Select subbase should conform to Colorado
Department of Transportation Class 1 specifications.
• Placement and Compaction:
1. Place and compactfill in horizontal lifts, using equipment and procedures that
will produce recommended moisture contents and densities throughout the
lift.
2. No fill should beplaced over frozen ground.
3. Materials should be compacted to the following:
Minimum Percent
Material (ASTM D698)
Subgrade soils beneath fill areas .....................
95
On -site soils or approved imported fill:
Beneath foundations ..........................
98
Beneath slabs .............................
95
Beneath pavements .........................
95
Beneath clay liner for canal ....................
95
Aggregate base (beneath pavements) ..................
95
Miscellaneous backfill ..............................
90
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4. All exposed areas which will receive fill, upper level floor slabs, a clay liner
or pavement, once properly cleared, should be scarified to a minimum depth
of 8 inches, conditioned to near optimum moisture content, and compacted.
5.. On -site clay soils in proposed pavement areas may pump or become unstable
or unworkable at high water contents. Workability may be improved by
scarifying and drying. Overexcavation of wet zones and replacement with
granular materials may be necessary. Lightweight excavation equipment may
be required to reduce subgrade pumping.
Use of lime, fly ash, kiln dust, cement or geotextiles could also be considered
as a stabilization technique. Laboratory evaluation is recommended to
determine the effect of chemical stabilization on subgrade soils prior to
construction.
Proof -rolling of the subgrade may be required to determine stability prior to
paving.
• Fill Materials:
1. Clean on -site sandy lean clay or approved imported materials may be used as
fill material for the following:
• general site grading
• foundation areas
• interior floor slab areas
• exterior slab areas
• pavement areas
• foundation backfill
2. Frozen soils should not be used as fill or backfill.
3. Imported soils (if required) should conform to the following:
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• Placing compacted backfill against the exterior side of curb and gutter; and,
• Placing curb, gutter and/or sidewalk directly on subgrade soils without the
use of base course materials.
Preventative maintenance should . be planned and provided for an on -going pavement
management program in order to enhance future pavement performance. Preventative
maintenance activities are intended to slow the rate of pavement deterioration, and to
preserve the pavement investment.
Preventative maintenance consists of both localized maintenance (e.g. crack sealing and
patching) and global maintenance (e.g. surface sealing). Preventative maintenance is
usually the first priority when implementing a planned pavement maintenance program and
provides the highest return on investment for pavements.
Recommended preventative maintenance policies for asphalt and jointed. concrete
pavements, based upon type and severity of distress, are provided in Appendix D. Prior to
implementing any maintenance, additional engineering observation is recommended to
determine the type and extent of preventative maintenance.
Earthwork:
• Site Clearing and Subgrade Preparation:
1. Strip and remove existing vegetation and any other deleterious materials from
proposed building, pavement, box culvert and canal realignment areas.
2. If unexpected fills or underground facilities are encountered during site
clearing, such features should be removed and the excavation thoroughly
cleaned prior to backfill placement and/or construction. All excavations
should be observed by the geotechnical engineer prior to backfill placement.
3. Stripped materials consisting of vegetation and organic materials should be
wasted from the site, or used to revegetate exposed slopes after completion
of grading operations.
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Concrete should be deposited by truck mixers or agitators and placed a maximum of 90
minutes from time the water is added to the mix. Other specifications outlined by the
Colorado Department of Transportation should be followed.
Longitudinal and transverse joints should be provided as needed in concrete pavements for
expansion/contraction and isolation. The location and extent of joints should be based upon
the final pavement geometry and should be placed (in feet), at roughly twice the slab
thickness (in inches), on center in either direction. Sawed joints should be cut within 24-
hours of concrete placement, and should be a minimum of 25% of slab thickness plus 1/4
inch. All joints should be sealed to prevent entry of foreign material and dowelled where
necessary for load transfer. Where dowels cannot be used at joints accessible to wheel
loads, pavement thickness should be increased by 25 percent at the joints and tapered to
regular thickness in 5 feet.
Future performance of pavements constructed on the clay soils at this site will be
dependent upon several factors, including:
• maintaining stable moisture content of the subgrade soils; and,
• providing for a planned program of preventative maintenance.
Since the clay soils on the site have shrink/swell characteristics, pavements could crack in
the future primarily because of expansion of the soils when subjected to an increase in
moisture content to the subgrade. The cracking, while not desirable, does not necessarily
constitute structural failure of the pavement.
The performance of all pavements can be enhanced by minimizing excess moisture which
can reach the subgrade soils. The following recommendations should be considered at
minimum:
• Site grading at a minimum 2% grade away from the pavements;
• Compaction of any utility trenches for landscaped areas to the same criteria
as the pavement subgrade;
• Sealing all landscaped areas in, or adjacent to pavements to minimize or
prevent moisture migration to subgrade soils;
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Aggregate base course and select subbase should be placed in lifts not exceeding six inches
and should be compacted to a minimum of 95% Standard Proctor Density (ASTM D698).
Asphalt concrete should be obtained from an approved mix design stating the Marshall or
Hveem properties, optimum asphalt content, job mix formula, and recommended mixing and
placing temperatures.. Aggregate used in asphalt concrete should meet a particular
gradation. Use of materials meeting Colorado Department of Transportation Grading C or
CX specification is recommended. The mix design should be submitted prior to construction
to verify its adequacy. The asphalt materials should be placed in maximum 3-inch lifts, and
should be compacted to a minimum. of 95% Marshall or Hveem density (ASTM D1559)
(ASTM D1560).
Plant -mixed bituminous base course should be composed of a mixture of aggregate, filler
and additives if required, and approved bituminous material. The bituminous base should
conform .to an approved mix design stating the Marshall or Hveem properties, optimum
asphalt content, job mix formula, and recommended mixing and placing temperatures.
Aggregate used in plant -mixed bituminous base course should meet a particular gradation.
Use of aggregates meeting Colorado Department of Transportation Grading G or C
specifications is recommended. The mix design should be submitted prior to construction
to verify it adequacy. The asphalt material should be placed in maximum 3-inch lifts, and
should be compacted to a minimum of 95% Marshall or Hveem density (ASTM D1559)
(ASTM D1560).
Where rigid pavements are used, the concrete should be obtained from an approved mix
design with the following minimum properties:
• Modulus of Rupture @ 28 days ................. 650 psi minimum
• Strength Requirements ........................... ASTM C94
• Minimum Cement Content ................ I .... 6.5 sacks/cu. yd.
• Cement Type ................................. Type I Portland
• Entrained Air Content .............................. 6 to 8%
• Concrete Aggregate ............ ASTM C33 and CDOT Section 703
• Aggregate Size ............................. 1 inch maximum
0 Maximum Water Content .................... 0.49 lb/lb of cement
• Maximum Allowable Slump . 4 inches
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The rigid pavement thicknesses for each traffic category were determined on the basis of
the AASHTO design equation.
Recommended alternatives for flexible and rigid pavements, summarized for each traffic
area, are as follows:
Recommended Pavement Section Tfiickness.(inches}
Traffic Area
Alter
native
Asphalt
Aggregate
Select:;
Plant=Mixed
Portland
Concrete
B..ase
> Su66ase
Bituminous.'
Cement
Yatal
Surface
Course
Base
Concrete
A
3
8
11
Belleview
B
2
4
6
C
6
6
A
3
10
13
Westbury
B
2
4'/2
6 %:
C
6
6
A
5
12
7
24
Shields
B
4
7 %:
11 y=
C
I
1 1
8
8
Each alternative should be investigated with respect to current material availability and
economic conditions.
Aggregate base course (if used on the site) should consist of a blend of sand and gravel
which meets strict specifications for quality and gradation. Use of materials meeting
Colorado Department of Transportation Class 5 or 6 specifications is recommended for base
course. Use of materials meeting Colorado Department of Transportation Class 1
specifications is recommended for select subbase.
In addition, the base course material should be moisture stable. Moisture stability is
determined by R-value testing which shows a maximum 12 point difference in R-values
between exudation pressures of 300 psi and 100 psi. Aggregate base course material
should be tested to determined compliance with these specifications prior to importation to
the site.
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it is recommended that the new canal slopes be covered with a minimum of 6 inches of
topsoil and seeded with native.grasses or other suitable vegetation.
Pavement Design and Construction: Design of pavements for the project have been based
on the procedures outlined in the 1986 Guideline for Design of Pavement Structures by the
J American Association of State Highway and Transportation Officials (AASHTO). Areas
within proposed pavements on the site will be divided into three categories based upon
anticipated traffic and usage.
Traffic criteria provided for pavement thickness designs include 18-kip equivalent daily load
applications (EDLA's) of 7 for Belleview Drive, 12 for Westbury Drive and 220 for South
Shields Street.
Based upon AASHTO criteria, Colorado is located within Climatic Region VI of the United
States. This region is characterized as being dry, with hard ground freeze and spring thaw.
The spring thaw condition typically results in saturated or near -saturated subgrade soil
moisture conditions. The AASHTO criteria suggests that these moisture conditions are
prevalent for approximately 12-1/2% of the annual moisture variation cycle.
Local drainage characteristics of proposed pavement areas are considered to be good.
These characteristics, coupled with the approximate duration of saturated subgrade
J conditions, results in a design drainage coefficient of 1.0 when applying the AASHTO
criteria for design.
For flexible pavement design, terminal serviceability indices of 2.0 for the residential streets
and 2.5 for South Shields Street were utilized along with inherent reliabilities of 70% for
residential streets and 90% for South Shields Street. A design R-value of 6.5 was used for
the residential streets and South Shields Street. The structural numbers (SN) of the
pavement sections were determined using these factors in the 1986 AASHTO design
equation.
In addition to the flexible pavement design analyses, a rigid pavement design analysis was
J completed, based upon AASHTO design procedures. Rigid pavement design is based on an
evaluation of the Modulus of Subgrade Reaction of the soils (K-value), the Modulus of
J Rupture of the concrete, and other factors previously outlined. The design K-value of 100 .
for the subgrade soil was determined by correlation to the laboratory tests results. A
l modulus of rupture of 650 psi (working stress 488 psi) was used for pavement concrete.
J
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minimum 4-inch layer of clean -graded gravel should be placed beneath all
other interior slabs.
• Floor slabs should not be constructed on frozen subgrade.
• Other design and construction considerations, as outlined in the ACI Design
Manual, Section 302.1 R are recommended.
Box Culvert Foundation System: It is recommended the box culvert be founded on original,
undisturbed soil. If the subgrade soil is saturated or unstable, the subgrade below the box
culvert should be overexcavated and backfilled with an approved granular material. The box
culvert may be designed for a maximum allowable bearing capacity of 1,500 psf (dead load
plus maximum live load). The predicted settlement under the above maximum loading
should be less. than 1 inch, generally considered to be within acceptable tolerances. Cutoff
walls should be provided below the upstream and downstream ends of the box culvert to
minimize erosion in the area of the culvert.
Lateral Earth Pressures: The following equivalent fluid pressures are recommended for on -
site clay soils above any free water surface:
Active Pressure - 45 psf/ft.
Passive Pressure - 325 psf/ft.
At Rest Pressure - 65 psf/ft.
The lateral earth pressures herein are not applicable for submerged soils. Additional
recommendations may be necessary if such conditions are to be included in the design.
Fill against walls should be compacted to densities specified in the "Earthwork" section of
this report. Medium to high plasticity clay soils or claystone should not be used as backfill
against. walls. Compaction of each lift adjacent to walls should be accomplished with hand -
operated tampers or other lightweight compactors. Overcompaction may cause excessive
lateral earth pressures which could result in wall movement.
Canal Realignment: The canal realignment should be constructed with maximum 2:1
slopes. The slopes should be lined with at least 1 foot of clay having a permeability of
1 x10-6 cm/sec or less. The clay liner and 8 inches of subgrade below the clay liner should
be compacted as outlined in the "Earthwork" section of this report. To minimize erosion,.
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Foundations placed within 3 feet of groundwater and/or bedrock should be surrounded by
a perimeter drainage system. The drainage system should be constructed around the
exterior perimeter of the basement foundation and slope at a minimum Ma inch per foot. The
drainage system should empty into a suitable outlet such as a sump and pump system.
The drainage system should consist of a properly sized perforated pipe, embedded in free -
draining gravel, placed in a trench at least 12 inches wide. Gravel should extend a minimum
of 3-inches beneath the bottom of the pipe, and at least 1 foot above the bottom of the
foundation wall. The gravel should be covered with drainage fabric prior to placement of
foundation backfill.
Floor Slab Design and Construction: Due to the high expansive potential of the claystone
bedrock, differential movement of a floor slab -on -grade may occur should the bedrock
1 increase in moisture content. Use of floor systems supported structurally independent of
_ the subgrade is a positive means of eliminating the potentially detrimental effects of floor
movement where slabs are founded on or within 3 feet of the bedrock stratum. If the
owner opts for slab -on -grade construction and is willing to assume the risk of future slab
movement and related structural damage, the following precaution is recommended:
• A minimum 2-inch void space should be constructed above, or below non -
bearing partition walls placed on the floor slab. Special framing details should
be provided at doorjambs and frames within partition walls to avoid potential
distortion. Partition walls should be isolated from suspended ceilings.
The following recommendations are applicable to all slab -on -grade construction:
Positive separations and/or isolation joints should be provided between slabs
and all foundations, columns or utility lines to allow independent movement.
• Contraction joints should be provided in slabs to control the location and
extent of cracking. Maximum joint spacing of 15 to 20 feet in each direction
is recommended.
• Interior trench backfill placed beneath slabs should be compacted in
accordance with recommended specifications outlined below.
• A minimum 8-inch layer of free -draining gravel should be placed beneath
basement floor slabs in conjunction with the underslab drainage system. A
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All piers should be reinforced full depth for the applied axial, lateral and uplift stresses
imposed. The amount of reinforcing steel for expansion should be determined by the tensile
force created by the uplift force on each pier, with allowance for dead -load.
To reduce potential uplift forces on piers, use of long grade beam spans to increase
individual pier loading, and small diameter piers are recommended. For this project, use of
a minimum pier diameter of 10 inches is recommended. A minimum 4 inch void space
should be provided beneath grade beams between piers. The void material should be of
suitable strength to support the weight of fresh concrete used in grade beam construction,
and to avoid collapse when foundation backfill is placed.
J Drilling to design depths should be possible with conventional single -flight power augers.
Groundwater conditions indicate that temporary steel casing may be required to properly
drill and clean piers prior to concrete placement. Groundwater should be removed from
each pier hole prior to concrete placement. Pier concrete should be placed immediately
after completion of drilling and cleaning: If pier concrete cannot be placed in dry conditions,
a tremie should be used for concrete placement. Due to potential sloughing and raveling,
foundation concrete quantities may exceed calculated geometric volumes.
If casing is used for pier construction, it should be withdrawn in a slow continuous manner
maintaining a sufficient head of concrete to prevent infiltration of water or the creation of
voids in pier concrete. Pier concrete should have a relatively high fluidity when placed in
Jcased pier holes or through a tremie. Pier concrete with slump in the range of 5 to.7 inches
is recommended.
JTo provide increased resistance to potential uplift forces, the sides of each pier should be
mechanically roughened in the bearing strata. This should be accomplished by a roughening
tooth placed on the auger. Pier bearing surfaces must be cleaned prior to concrete
placement. A representative of the geotechnical engineer should inspect the bearing surface
Jand pier configuration.
Basement Construction: Groundwater was not encountered within a depth of 10 feet on
the site. Therefore, full -depth basement construction is considered acceptable on the site.
Perched groundwater may occur at times since the bedrock is relatively impermeable and
Jmay tend to trap water. Completion of site development, including installation of
landscaping and irrigation systems, will likely lead to perched groundwater development.
J
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J Footings should be proportioned to minimize differential foundation movement.
Proportioning on the basis of equal' total settlement is recommended; however,
proportioning to relative constant dead -load pressure will also reduce differential settlement
J between adjacent footings. Total or differential settlement resulting from the assumed
structural loads are estimated to be on the order of % inch or less. Additional foundation
J movements could occur if water from any source infiltrates the foundation soils; therefore,
proper drainage should be provided in the final design and during construction. .
Foundations and masonry walls should be reinforced as necessary to reduce the potential
for distress caused by differential foundation movement. The use of joints at openings or
other discontinuities in masonry walls is recommended.
JFoundation excavations should be observed by the geotechnical engineer. If the soil
conditions encountered differ from those presented in this report, supplemental
recommendations may be required.
Foundation Systems - Piers: Structures founded in or within 3 feet of the bedrock stratum
should be supported by drilled pier foundation systems. Drilled foundation systems will
most likely be appropriate in the west and southeast portions of the property.
Straight shaft piers, drilled a minimum of 5 feet into firm bedrock, with a minimum shaft
length of 12 feet are recommended.
For axial compression loads, piers may be design for a maximum end -bearing pressure of
J 20,000 pounds per square foot (psf), and skin friction of 2,000 psf for the portion of the
pier in firm bedrock.
Required pier penetration should be balanced against potential uplift forces due to expansion
of the subsoils and bedrock on the site. For design purposes, the uplift force on each pier
Jcan be determined on the basis of the following equation:
U..= 25xD.
JWhere: UP = the uplift force in kips, and
D = the pier diameter in feet
Uplift forces on piers should be resisted by a combination of dead load and pier penetration
Jbelow a depth of 7 feet and in the bearing stratum.
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Laboratory test results indicate the clay soils at anticipated foundation bearing depth have
low to moderate expansive potential and moderate bearing capacity. The bedrock has high
expansive potential and high bearing capacity.
Groundwater Conditions: Groundwater was not observed in any test boring at the time of
the field exploration. However, when checked 4 to 5 days after drilling, groundwater was
measured at depths of 10.6, 12.4 and 10.3 feet in borings 4, 5 and 6, respectively. These
observations represent only current groundwater conditions, and may not be indicative of
other times, or at other locations. Groundwater levels can be expected to fluctuate with
varying seasonal and weather conditions.
Zones of perched and/or trapped groundwater may also occur at times in the subsurface
soils overlying bedrock, on top of the bedrock surface or within permeable fractures in the
bedrock materials. The location and amount of perched water is dependent upon several
factors, including hydrologic conditions, type of site development, irrigation demands on or
adjacent to the site, fluctuations in water features, and seasonal and weather conditions.
Borings 1 and 3 were cased to a depth of 10 feet to monitor fluctuations in groundwater
levels.. The possibility of groundwater fluctuations should be considered when developing
design and construction plans for the project.
CONCLUSIONS AND RECOMMENDATIONS
Foundation Systems - Footings: Spread footing and/or grade beam foundations bearing
upon undisturbed subsoils and/or engineered fill are recommended for support of the
proposed structures founded a minimum of 3 feet above the bedrock stratum. The footings
may be designed for a maximum bearing pressure of 1,500 psf. The design bearing
pressure applies to dead loads plus '/2 design live load conditions. The ,design bearing
pressure may be increased by one-third when considering total loads that include wind or
seismic conditions. In addition, the footings and/or grade beams should be sized to maintain
a minimum dead load pressure of 500 psf.
Exterior footings should be placed a minimum of 30 inches below finished grade for frost
protection. Interior footings should bear a minimum of 12 inches below finished grade.
Finished grade is the lowest adjacent grade for perimeter footings and floor level for interior
footings.
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JSUBSURFACE CONDITIONS
Soil and Bedrock Conditions: The following describes the characteristics of the primary soil
Jstrata in order of increasing depths:
J • Topsoil. A '/s foot layer of topsoil was encountered at the surface of borings 1
through 3 and 5 through 7. The topsoil has been penetrated by root growth and
organic matter.
• Fill. A 3 foot Layer a fill was encountered at the surface of borings 8 and 9. The fill
consists of fat clay. It is not known whether the fill has been uniformly or properly
compacted.
• Lean Clay. A layer of dark brown lean clay was encountered below the topsoil in
borings 1 through 3 and 5 through 7 and at the surface of boring 4. The lean clay
is moist and contains minor quantities of sand.
• Sandy Lean Clay. A layer of tan to red sandy lean clay was encountered at depths
of '/: to 3 feet in borings 2 through 4 and 6 through 9 and extends to the underlying
bedrock or to the depth explored. The sandy lean clay is moist to wet with depth
and contains substantial quantities of sand.
• Clayey Sand with Gravel and Sand with Gravel. A layer of clayey sand with gravel
was encountered at a depth of 3 feet in boring 1 and extends to the underlying
bedrock stratum. The clayey sand with gravel is moist and contains substantial
quantities of clay. A layer of sand with gravel was encountered at a depth of 7'/z
feet in boring 6 and extends to the underlying bedrock stratum. The sand with
gravel is relatively clean and is moist to wet with depth.
0 Claystone and Claystone-Sandstone Bedrock. The bedrock stratum was encountered
in borings 1 through 3 and 5 through 9 at depths of 4 to 14'/: feet. The upper 2 to
3 feet of bedrock is weathered.
Field and Laboratory Test Results: Field test results indicate the clay soils vary from
medium stiff to very stiff in consistency. The clayey sand with gravel is dense and the sand
with gravel is loose to medium dense in relatively density. The weathered bedrock is soft
to moderately hard and the underlying bedrock is hard.
Geotechnical Engineering Exploration
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ELI Project No. 20955035
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Laboratory Testing: All samples retrieved during the field exploration were returned to the
laboratory for observation by the project geotechnical engineer, and were classified in
accordance with the Unified Soil Classification System described in Appendix C. Samples
of bedrock were classified in accordance with the general notes for Bedrock Classification.
At that time, the field descriptions were confirmed or modified as necessary and an
applicable laboratory testing program was formulated to determine engineering properties
of the subsurface materials. Boring logs were prepared and are presented in Appendix A.
Selected soil and bedrock samples were tested for the following engineering properties:
• Water content
• Dry density
• Consolidation
• Compressive strength
• Expansion
• Liquid limit
• Plasticity index
• Percent fines
• R-value
• Water soluble sulfate content
The significance and purpose of each laboratory test is described in Appendix C. Laboratory
test results are presented on the, boring logs and in Appendix B, and were used for the
geotechnical engineering analyses, and the development of foundation, pavement and
earthwork recommendations. All laboratory tests were performed in general accordance
with the applicable ASTM, local or other accepted standards.
SITE CONDITIONS
The site is a field vegetated with low, dense grass and weeds. The Pleasant Valley and
Lake Canal flows in a generally southeast direction across the west half of the site. The
property is bordered by Gress Gallery and the first filing of the Westbury P.U.D. to the
north, undeveloped land to the south, South Shields Street to the east and The Ridge
subdivision to the west. The west portion of the site exhibits slight surface drainage to the
northeast, toward the Pleasant Valley and Lake Canal. The east portion of the site exhibits
slight surface drainage to the northeast portion of the site.
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constructed where Belleview Drive crosses the canal. South Shields Street will be widened
and improved along the east edge of the site.
Although final site grading plans were not available prior to preparation of this report,
ground floor levels of the residences are anticipated to be at or near existing site grade.
SITE EXPLORATION
The scope of the services performed for this project included site reconnaissance by an
engineering geologist, a subsurface exploration program, laboratory testing and engineering
analysis.
Field Exploration: A total of nine (9) test borings were drilled on March 1 and 3, 1995 to
depths of 10 to 20 feet at the locations shown on the Site Plan, Figure 1. Five borings
were drilled in proposed building areas, and four borings were drilled in proposed pavement
areas. All borings were advanced with a truck -mounted drilling rig, utilizing 4-inch diameter
solid stem auger.
The borings were located in the field relative to the property lines and South Shields Street.
Elevations were determined at each boring location by interpolation from contours on a
topographic map provided by Cityscape Urban Design, Inc. The accuracy of boring
locations and elevations should only be assumed to the level implied by the methods used.
Continuous lithologic logs of each boring were recorded by the engineering geologist during
the drilling operations. At selected intervals, samples of the subsurface materials were
taken by pushing thin -walled Shelby tubes, or by driving split -spoon samplers.
Representative bulk samples of subsurface materials were obtained from pavement borings.
Penetration resistance measurements were obtained by driving the split -spoon into the
J
subsurface materials with a 140-pound hammer falling 30 inches. The penetration
resistance value is a useful index to the consistency, relative density or hardness of the
materials encountered.
J Groundwater measurements were made in each boring at the time of the site exploration,
Jand four to five days after drilling.
2
GEOTECHNICAL ENGINEERING REPORT
WESTBURY P.U.D., 2ND FILING
SOUTH SHIELDS STREET
FORT COLLINS, COLORADO
ELI Project No. 20955035
March 17, 1995
INTRODUCTION
Terracon
This report contains the results of our geotechnical engineering exploration for the proposed
subdivision to be located on the west side of South Shields Street, south of Harmony Road
in southwest Fort Collins, Colorado. The site is located in the NE'A of the NE'/< of Section
3, Township 6 North, Range 69 West of the 6th Principal Meridian.
The purpose of these services is to provide information and geotechnical engineering
recommendations relative to:
D
• subsurface soil and bedrock conditions
• groundwater conditions
• foundation design and construction
• basement construction
• floor slab design and construction
• box culvert design and construction
• lateral earth pressures
0 canal realignment
• pavement design and construction
0 earthwork
• drainage
The conclusions and recommendations contained in this report are based upon the results
of field and laboratory testing, engineering analysis, our experience with similar soil
conditions and structures and our understanding of the proposed project.
PROPOSED CONSTRUCTION
Based on information provided concerning construction, the proposed subdivision will
include 32 single-family residences and 25 attached homes. Westbury Drive will be
extended across the site and a local street, Belleview Drive, will also be constructed. A
portion of the Pleasant Valley and Lake Canal will be relocated. A box culvert will be
Geotechnical Engineering Exploration
Linder Real Estate
ELI Project No. 20955035
Terracon
Structures founded in or within 3 feet of the bedrock should be supported by a drilled pier
foundation system. The bedrock is encountered at relatively shallow depths in the west and
southeast portions of the site. Consideration should be given to the use of structural floor
systems in conjunction with the drilled pier foundations if no slab movement can be
tolerated.
Other design and construction details, based upon geotechnical conditions, are presented
in the report.
We appreciate being of service during the geotechnical engineering phase of this project,
and are prepared to assist you during the design and construction phases as well. If you
have any questions concerning this report or any of our testing, inspection, design and
consulting services, please do not hesitate to contact us.
Sincerely;
EMPIRE LABORATORIES, INC.
J A Division of The Terracon Companies, Inc.
, ,M1 r
Prepared By: C� SC
Ja . Schoenfeld, P.E. %,�1'���AL�Q�C
Geotechnical Engineer
Reviewed by: (ERGS,y�
6d��0�8TEgFO
4808
Chester C. Smith, P.E. i�
�^ o
Division Manager
LRS/CCS/dmf
Copies to: Addressee (2)
Cityscape Urban Design (1)
Empire Laboratories, Inc.
A Division of The Terracon Companies, Inc.
P.O. Box 503.301 No. Howes
Fort Collins, Colorado 80522
(303)484-0359
Fax (303) 484-0454
Chester C. Smith, P.E.
Larry G. O'Dell, P.E.
Neil R. Sherrod, C.P.G.
March 17, 1995
Linder Real Estate
3500 JFK Parkway, Suite 221
Fort Collins, CO 80525
Attn: Mr. Mark Linder
Re: Geotechnical Engineering Report
Westbury P.U.D., 2nd Filing
Fort Collins, Colorado
ELI Project No. 20955035
Empire Laboratories, Inc. (ELI) has completed a geotechnical engineering exploration for the
proposed subdivision to be located on the west side of South Shields Street, south of
Harmony Road in southwest Fort Collins, Colorado. This study was performed in general
accordance with our proposal number 2095053 dated February 28, 1995.
The results of our engineering study, including the boring location diagram, laboratory test
results, test boring records, and the geotechnical recommendations needed to aid in the
design and construction of foundations, pavement and other earth connected phases of this.
project are attached.
The subsurface soils consisted of lean clay, sandy lean clay and sand with gravel overlying
claystone and claystone-sandstone bedrock. The information obtained by the results of field
exploration and laboratory testing indicate the clay soil at anticipated foundation bearing
depth has low to moderate expansive potential and the claystone bedrock has high
expansive potential. The soils and bedrock at anticipated foundation depth have moderate
and high load bearing capabilities, respectively.
Structures founded a minimum of 3 feet above the bedrock may be supported by a spread
footing and/or grade beam foundation system. Slab -on -grade may be utilized for the interior
floor system in conjunction with a spread footing and/or grade beam foundation system
provided care is taken in the placement and compaction of the subgrade soil.
Offices of The Terracon Companies, Inc. Geotechnical, Environmental and Materials Engineers
Adzona ■ Arkansas ■ Colorado ■ Idaho . ■ Illinois ■ Iowa ■ Kansas ■ Minnesota
Missouri ■ Montana ■ Nebraska ■ Nevada ■ Oklahoma ■ Texas ■ Utah ■ Wyoming
niter 1Tv curruccoiur. cttant: 10s4
Geotechnical Engineering Exploration
Linder Real Estate
ELI Project No. 20955035
TABLE OF CONTENTS (Cont'd)
APPENDIX A
Figure No.
SitePlan .............................................. A.. 1
Logs of Borings .................. Al thru A9
APPENDIX B
Consolidation Tests ................................... B1 thru B2
R-Value Tests ....................................... B3 thru B4
Summary of Test Results .................................... B5
APPENDIX C: GENERAL NOTES
Drilling & Exploration ........................................ C1
Unified Soil Classification .................................... C2
Bedrock Classification, Sedimentary Bedrock ....................... C3
Laboratory Testing, Significance and Purpose ...................... C4
Report Terminology ........................................ C5
APPENDIX D
Recommended Preventative Maintenance -Asphalt Concrete Pavements .... D1
Recommended Preventative Maintenance -Jointed Concrete Pavements .... D2
Geotechnical Engineering Exploration
Linder Real Estate
ELI Project No. 20955035
TABLE OF CONTENTS
JPage No.
iLetter of Transmittal ............................................... ii
JINTRODUCTION ................................................ 1
PROPOSED CONSTRUCTION ....................................... 1
SITE EXPLORATION ............................................. 2
J Field Exploration . ' .... • .................. • .. , , . , .......... 2
Laboratory Testing 3
SITECONDITIONS .............................................. 3
SUBSURFACE CONDITIONS ....................................... 4
Soil and Bedrock Conditions .................................. 4
Field and Laboratory Test Results ............................... 4
Groundwater Conditions ..................................... 5
CONCLUSIONS AND RECOMMENDATIONS ............................ 5
Foundation Systems ........................................ 5
Foundation Systems ........................................ 6
Basement Construction ...................................... 7
Floor Slab Design and Construction ............................. 8
Box Culvert Foundation System ................................ 9
Lateral Earth Pressures ...................................... 9
Canal Realignment ......................................... 9
Pavement Design and Construction ............................. 10
Earthwork............................................... 14
Site Clearing and Subgrade Preparation ...................... 14
Fill Materials ........................................ 15
Placement and Compaction .............................. 16
Compliance......................................... 17
Excavation and Trench Construction ........................ 17
Drainage................................................ 17
Surface Drainage ..................................... 17
Additional Design and Construction Considerations .................. 18
Exterior Slab Design and Construction ...................... 18
Underground Utility Systems ............................. 18
Corrosion Protection ................................... 19
GENERAL COMMENTS ........................................... 19
GEOTECHNICAL ENGINEERING REPORT
WESTBURY P.U.D., 2ND FILING
SOUTH SHIELDS STREET
FORT COLLINS, COLORADO
ELI PROJECT NO. 20955035
March 17, 1995
Prepared for•
LINDER REAL ESTATE
3500 JFK PARKWAY, SUITE 221
FORT COLLINS, COLORADO 80525
ATTN: MR. MARK LINDER
Prepared by. -
Empire Laboratories, Inc.
A Division of The Terracon Companies, Inc.
Empire Laboratories, Inc.
A Division of The Terracon Comoanies. Inc.
GEOTECHNICAL ENGINEERING REPORT
WESTBURY P.U.D., 2ND FILING
SOUTH SHIELDS STREET
FORT COLLINS, COLORADO
ELI PROJECT NO. 20955035
March 17, 1995
A Division of
The Terracon Companies, Inc.