HomeMy WebLinkAboutKINGDOM HALL - PDP - 18-05B - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTresults of these tests will be furnished to the contractor. These test results shall be the
basis of control for compaction effort.
DENSITY TESTS
The density and moisture content of each layer of compacted fill will be determined by the
Soils Engineerin accordance with ASTM D 1556, D2167 orD2922, at frequencies required
by municipal codes, city or county inspectors, or by the Soils Engineer. Any material found
to not comply with the minimum specified density shall be recompacted and retested until
the required density is obtained. The results of all -density tests shall be furnished to both
the owner and the contractor by the Soils Engineer.
COMPACTION REQUIREMENTS
The following compaction requirements are based on the Standard proctor (ASTM D 698).
Location
Compaction
Overlot Fills - Supporting Foundations, 95%
Exterior Slabs, Roadways, Driveways, Curb, Gutters,
Drive -over Walks
Overlot Fills - Backlots Where No 90%
Structures Will Be Located
Utility Lines
Under Roadways, Curb/Walk, etc. 95%
Under Yards, Backlots, etc. 90%
Interior Floor Slabs
95% f 2% "
* If expansive material is used for fill, moisture content should be 4% to +3% above
optimum.
"` If expansive material is used for fill, moisture content should be optimum to 4% above
optimum.
MOISTURE - DENSITY DETERMINATION
(PROCTOR)
Samples of representative fill materials to be placed shall be furnished by the contractor
to the Soils Engineer at least 48 hours prior to compaction testing for determination of
maximum density and optimum moisture for these materials. Tests for this determination
will be made using methods conforming to requirements of ASTM D 698. Copies of the
PLACING FILL
No sod, brush, frozen material or other deleterious or unsuitable material shall be placed
in the fill. The select fill material shall be placed in uniform, level layers in a manner which
will preclude the formation of lenses and will result in a uniformly compacted fill. The
thickness of each compacted lift shall be six inches (6') or as specified, as determined by
the capability of the compaction equipment. Each lift shall be compacted to the
requirements described in Compaction Requirements of this Appendix or as specified
otherwise.
MOISTURE CONTROL
The fill material in each layer, at the time of compaction, shall contain the amount of
moisture required for optimum density; and the moisture shall be uniform throughout the
fill. Expansive soils may need moisture above the optimum moisture content in order to
pre -swell the soil as based on laboratory tests. The contractor maybe required to add and
thoroughly mix moisture to the backfill material. If, in the opinion of the Soils Engineer, the
material proposed for use in the compacted fill is too wet to permit adequate compaction,
it shall be dried in an acceptable manner prior to placement and compaction or a suitable
imported fill material may be chosen.
COMPACTION METHODS
When an acceptable, uniform moisture content is obtained, each layershall be compacted
by a method acceptable to the Soils Engineer and as specified in the foregoing report as
determined by the Standard Proctor Test (ASTM D 698). Compaction shall be performed
by rolling with approved ramping rollers, three -wheel power rollers, or other approved
equipment well suited to the soil being compacted. If a sheepsfoot roller is used, it shall
be provided with cleaner bars so attached as to prevent the accumulation of material
between the tamper feet.
APPENDIX A
Suggested Specifications for Placement of Compacted Earth Fills and/or Backfills.
GENERAL
A Soils Engineer shall be the owner's representative to supervise and control all
compacted fill and/or compacted backfill placed on the project. The Soils Engineer shall
approve all earth materials prior to their use, the methods of placing, and the degree of
compaction obtained. A certificate of approval from the Soils Engineer will be required
prior to the owner's final acceptance of the filling operations.
MATERIALS
The soils used forcompacted fill beneath interior floor slabs and backfill around foundation
walls shall be relatively impervious and non -swelling. Fill materials utilized for street
subgrades shall have plasticities equal to orless than and/orR-values equal to orgreater
than those upon which the pavement recommendations were based. The materials used
should not have any rocks or lumps greater than six inches (6') and shall be free of
organics, trash, frozen ground or other deleterious matter. All materials used in either
compacted fill or compacted backfill shall be subject to the approval of the Soils Engineer.
PREPARATION OF SUBGRADE
All topsoil and vegetation shall be removed to a depth satisfactory to the Soils Engineer
before beginning preparation of the subgrade. The subgrade surface of the area to be
filled shall be scarified to a minimum depth of six inches (6'), uniformly moistened or dried
to within an acceptable moisture content range as determined by ASTM D 698 or as
otherwise specified. The surface shall be free of ruts, ridges or other uneven surfaces
which would prevent uniform compaction. The subgrade shall then be compacted to 95%
or greater of ASTM D 698 or as otherwise specified.
Test Hole No.: 3 Depth: 6 1/2 ft
Sample Description: sandy lean clay
Moisture Content: -- 12.4 % ---TDry Density: 104.4 lbs/ft
Swell: 0.7 %
SWELL/CONSOLIDATION
3.00
2.00
LU 1.00 -
::F 0.00 1
F
0
1-00 --Kd-ded
:1 -2.00
0
0 3.00
-4.00 -
-5.00 A
0.1 1 10 100
LOAD (KSF)
Water;
Test Hole No.: Depth: ft
Sample Description:
Moisture Content: % --TDry Density: lbs/ft'
Swell: % %
:'SWELL/CONSOLIDATION
6
T
4 -
0
< 0
0 -2 -
0
-4 i L I La.
Hih
-6
0.1 10 100
LOAD (KSF)
Client: Frederickson Group LLC
Landmark jProject No.: FREDEG-4J5F-02-709 777d
3521 W. Eisenhower Blvd.
Loveland, Colorado 80537 DRAWING NO,:
970-667-6286 1 3 1
Client: Frederickson Group LLC
Landmark jProject No.: FREDEG-4J5F-02-709 777d
3521 W. Eisenhower Blvd.
Loveland, Colorado 80537 DRAWING NO,:
970-667-6286 1 3 1
Test Hole No.:
2
Depth: 2 1/2 ft
Sample Description:
sandy lean clay
Moisture Content:
16.2 %
Dry Density: 86.6 Ibs/ft
Swell:
--- %
iS WELLICONSOLIDATION
2.00
Added
Wate ! j
j!I
0.00
ii
LU
-2.00
I
I
I
-4.00
—I
�
I
❑
I i I
i
I
i
I
I
-6.00
�
fn
o
-8.00
I
-10.00
0.1
1 10 100
LOAD (KSF)
Test Hole No.: 3 Depth: 2 1/2 ft
Sample Description: sandy lean clay
Moisture Content: 11.4 % D Densit 87.3 Ibs/ft3
Swell: --- %
LSWELUCONSOLIDATION I
2.00 Arlded
0.00
J
3 -2.00
y -4.00
-6.00
❑
o LLL
-8.00
N
o -10.00 -
U
-12.00
-14.00
0.1 1 10 100
LOAD (KSF)
-
�� Client: Frederickson GroupLLC
(, Lu nd m imirk Project No.: FREDEG-4J5F-02-709 77771
3521 W. Eisenhower Blvd.
Loveland, Colorado 80537 DRAWING NO.:
970-667-6286
2
Test Hole No.: 1 Depth: 2 ft
Sample Description: sandy lean clay
Moisture Content: 20.7 % Dry Density: 102.7 lbs/ftj
Swell: 0.1.%
'SWELLJCONSO Ll DATION
1.00
-j Water,
71\
0.00 1
U
z
0
1.00
O
cn
z
U0 -2.00
-3.00
0.1 1 10 100
LOAD (KSF)
dded
A
Water!
Test Hole No.: 7 1/2 ft
Sample Description: clayey sand w/ fine gravel
Moisture Content: 9.3 % JlDry Density:- 109.7 IbS/ft3
Swell: --- %
rSWELUCONSOLIDATION
1.00
0.00 LL 11
U1
3: -1.00
0
z -z.uu i
LLi
.
'0�' -3.00 -
0
z
ul -4.00
0
-5.00
T
-6.00 J
0.1 1 10 100
LOAD (KSF)
Water!
Test Hole No.: 7 1/2 ft
Sample Description: clayey sand w/ fine gravel
Moisture Content: 9.3 % JlDry Density:- 109.7 IbS/ft3
Swell: --- %
rSWELUCONSOLIDATION
1.00
0.00 LL 11
U1
3: -1.00
0
z -z.uu i
LLi
.
'0�' -3.00 -
0
z
ul -4.00
0
-5.00
T
-6.00 J
0.1 1 10 100
LOAD (KSF)
III
h Client:
ur
Frederickson Group LLC
jProject No.: FREDEG-4J5F-02-709
Lundm
3521 W. Eisenhower Blvd.
Loveland, Colorado 80537 DRAWING NO.:
970-667-6286
1
LOG OF BORING BORING
NO.
CLIENT: The Frederickson Group LLC DRILL RIG: Acker AD -II 4
PROJECT NO: FREDEG-4J5F-02-709 ROD SIZE: AW
PROJECT LOCATION: Poudre Valley Congregation METHOD OF DRILLING: 4" s.s.
of Jehovas Witnessess DRILLER: LAM
DATE DRILLED: May 21, 2005 ENGINEER/GEOLOGIST: LAM
ELEVATION: natural grade WEATHER:
W
w
}
F
w
O
w
DESCRIPTION
J
� z
Z
z
w
REMARKS
=
Q-
Ui
W w
U
w
>-
¢
a
(n
Q
Op
LL
�U
to
U)
to
U
O d
sandy lean clay, med. stiff, moist,
CL
-#200=70%
-
dk. brown -brown -It. brown
L.L.= 41
P.I.= 20
-
-5.
no water encountered
-- ---
-10
-15-
-20-
-25
-30-
-35-
-40-
PLATE 6
-Landmark
ENGINEERING LTD.
LOG OF BORING
CLIENT: The Frederickson Group LLC DRILL RIG: Acker AD -II
PROJECT NO: FREDEG-4J5F-02-709 ROD SIZE: AW
PROJECT LOCATION: Poudre Valley Congregation METHOD OF DRILLING: 4" s.s.
of Jehovas Witnessess DRILLER: LAM
DATE DRILLED: May 21, 2005 ENGINEER/GEOLOGIST: LAM
ELEVATION: natural grade WEATHER:
_
F
W
>
W
Q
a
DESCRIPTION
v)
W
W
J
Q
z
Z
00
}
�
Z
w
w
WU
REMARKS
.
sandy lean clay, med. stiff, moist,
dk. brown -brown -It. brown
11.4
87.3
6/12
-5-
with sand & gravel lenses, brown -
red
12.4
104.4
v
9/12
-10
med. stiff -soft, v. moist -wet
\
-15-
7/12_ _
brown gray ______ __._
21.9
water @ 14'
20
-25-
-30-
-35-
-40-
PLATE 5
1Landmarh
ENGINEERING LTD.
LOG OF BORING BORING
NO.
CLIENT: The Frederickson Group LLC DRILL RIG: Acker AD -II 2
PROJECT NO: FREDEG-4J5F-02-709 ROD SIZE: AW
PROJECT LOCATION: Poudre Valley Congregation METHOD OF DRILLING: 4" s.s.
of Jehovas Witnessess DRILLER: LAM
DATE DRILLED: May 21, 2005 ENGINEER/GEOLOGIST: LAM
ELEVATION: natural grade WEATHER:
J
W
J
}
F
LLL
w
DESCRIPTION
z
w
REMARKS
=
m
a_
W
O F
0,
w
¢
c-
o
f
¢OO
xv
sandy lean clay, med. stiff, moist,
dk. brown -brown -It. brown
16.2
86.6
-
18/12
tan -cream
-5-
with sand & gravel lenses, brown -
red
12/12
9.7
-10-
-
med. stiff -soft, v. moist -wet
--
water @ 13.5'
-15
\\
stiff, brown -gray
-20-
14/12 _
...----�._.._.,-.__........__.._.
18.3
-25-
-30-
-35-
-40-
PLATE 4
�Undmark
ENGINEERING LTD.
LOG OF BORING BORING
NO.
CLIENT: The Frederickson Group LLC DRILL RIG: Acker AD -II
PROJECT NO: FREDEG-4J5F-02-709 ROD SIZE: AW
PROJECT LOCATION: Poudre Valley Congregation METHOD OF DRILLING: 4" s.s.
of Jehovas Witnessess DRILLER: LAM
DATE DRILLED: May 21, 2005 ENGINEER/GEOLOGIST: LAM
ELEVATION: natural grade WEATHER:
_
J
W
}
F
F-
w
DESCRIPTION
_
z
w
REMARKS
=~
ma_
w�
Cn
U
0—
w>_
Q
a
U~OpLL
n
W U
o
U)
U
cn
Z)
mo
\
sandy lean clay, med. stiff, moist,
dk. brown -brown -It. brown
20.7
102.7
5/12
-5-
tan -cream
with sand & gravel lenses, brown -
red
9.3
109.7
7/12
-10
'
7
\
—
water @ 12.5'
-15-
10/12
stiff, brown-gray
21.5
-20-
-25
-30-
-35-
-40-
PLATE 3
�QLandmarh
ENGINEERING LTD.
LEGEND OF SOIL AND ROCK SYMBOLS
FILL MATERIAL .
GRAVELS (GW,GP, GM,GC)
SANDS (SW, SF SM, SC )
SILTS (ML,MH )
CLAYS (CL,CH,OL,OH )
ORGANICS
WEATHERED BEDROCK
CLAYSTONE 81 SHALE
SILTSTONE
SANDSTONE
LIMESTONE
IGNEOUS/ METAMORPHIC
ROCKS
SYMBOLS COMBINED
TO REPRESENT SOIL
M IXTURES
Example:
SILTY CLAY
GRAVELLY CLAY
Depth Below
Surfar�
Water Level
After 24 Hours
y Thin -walled Sampler
spoon Sampler *
irnia Sampler
Sample
* Split -spoon sample utilizes a
140lb. hammer dropping 30"'
Recording number of blows
per 12" or partial increment.
(ASTM DI586)
ENGINEERS/ARCHITECTS/PLAN NERS/SURVEYORS/GEOTECHNICAL
3521 West Eisenhower Blvd., Loveland, Colorado 80537
(970) 667-6286 Denver (303) 629-7124 Fax (970) 667-6298
PLATE
NUMBER
2
u 1 1 OUT
rc) I T
/ I SE R+G
/ 15'T
I W \ I
I 11
l � /
3 I JW
o1
NN /
pp
3 ( Soo { I
II1 FOOGbLT IINt
I II I 5,OIS 9F.
I /
tB-
I I I
I '
i
L 1
PROPOSED.15' UTILITY, DRAINAGE
ACCESS EA5NENT
—
//
II
i
II
_i B-4
PORTICO
UVE
I
F
ND _ 10.
g —
EXIST EDGE
__----__---
_.... _ +O. OC. TYPICAL
5ECTICNLINE
FAST COUNTY ROAD 35, !KF(:uTFr? Roan)
PLATE 1
CLIENT: The Frederickson Group LLC
Qy (Examammlxe Lem TITLE: soil Boring Site Map
NGINEERS/ARCHITECTS/PLANNERS/SURVEYORS
3521 West Eisenhower Blvd., Loveland, Colorado 60537 PROJECT NUMBER: FREDEG-4J5F-02-709
(970) 667-6256 Denver (303) 629-7124 Fox (970) 667-6298
__ DATE: May 24, 2005 1 SCALE: 1"=501t
which could trap water are eliminated. Seals should be provided between curb and
pavement and at all joints to reduce moisture infiltration, Landscaped areas and detention
ponds in pavement areas should be avoided.
Routine maintenance such as sealing and repair of cracks annually and overlays at 5 to
7 year intervals are necessary to achieve long-term life of the pavement system. If the
design recommendations cannot be followed or anticipated traffic loads change
considerably, we should be contacted to review our recommendations.
GENERAL INFORMATION
The data presented herein were collected to help develop designs and cost estimates for
this project. Professional judgements on design alternatives and criteria are presented in
this report. These are based on evaluation of technical information gathered, partly on our
understanding of the characteristics of the proposed slab on grade church, and partly on
our experience with subsurface conditions in the area. We do not guarantee the
performance of the project in any respect, only that our engineering work and judgements
rendered meet the standard of care of our profession.
The test holes drilled were spaced to obtain a reasonably accurate picture of subsurface
conditions for design purposes. Variations from the conditions portrayed frequently occur.
These variations are sometimes sufficient to necessitate modifications in design.
We recommend that construction be continuously observed by a qualified soils technician,
trained and experienced in the field to take advantage of all opportunities to recognize
different conditions and minimize the risk of having some undetected condition which might
affect the performance of the foundation and pavement elements.
Course (A.B.C.) having an R-value between 70-77. A design drainage coefficient (M) of
1.0 was also used.
Rigid Portland Cementconcrete pavement designs were also calculated using
A.A.S.H.T.0. design procedures. These designs are based on a Modulus of Subgrade
Reaction of Soils (K-Value) of 150, a Concrete Modulus of Rupture of 650 p.s.i. with a
compressive strength of 4,000 p.s.i. and an air content between 5 - 8%.
Our design calculations indicate the appropriate areas can be paved using the following.
ANTICIPATED TRAFFIC
ASPHALT & BASE
FULL DEPTH
TYPE
CONCRETE
Main Traffic Corridors
3.5"H.B.P. &
8.0" A. B. C.
--
Automobile Parking Areas
3.5" H.B.P. &
6.0" A. B. C.
--
Loading Docks, Delivery
Not
Aprons & Dumpster Locations
Recommended
6"
We do recommend full depth, reinforced concrete pads be constructed at dumpster
locations, loadingdocks, deliveryaprons, entry aprons and otherareas where heavytrucks
turn at low speeds. Prior to paving, the subgrade should be scarified to a depth of 8",
moisture conditioned and compacted to at least 95% of maximum Standard Proctor dry
density. Other subgrade preparation recommendations can be found in Appendix A.
The primary cause of early pavement deterioration is water infiltration into the pavement
subgrade. The addition of moisture usually results in softening of the untreated subgrade
and the eventual failure of the pavement. We recommend drainage be designed for rapid
removal of surface runoff. Curb and gutter backfill should be compacted and sloped to
reduce ponding adjacent to the pavements. Final grading of the subgrade should be
carefully controlled so the design cross -slope is maintained and low spots in the subgrade
93
outside perimeter of the structure should be compacted at optimum moisture, or above,
and to at least 90 percent of Standard Proctor Density as determined by ASTM Standard
Test D-698. A suggested specification for placement of backfills is included as Appendix
A. Backfill material should be relatively impervious and non -swelling. The backfill should
be free of frozen soil, large dried clods, and organic matter. Backfilling should only be
accomplished when concrete strength and adequate support to foundation walls are
applied and acceptable to the Foundation Engineer. It is our opinion that the natural soils
at the site could be used for backfill material. Finished grades should be sloped away from
the structure on all sides to provide positive drainage. A minimum of 6 inches fall in the
first 10 feet is required. However, we recommend 12 inches of fall. The fall should be
maintained throughout the life of the structure. Sprinkling systems should not be installed
or direct water to within 10 feet of the structure. Downspouts with extensions are
recommended and should be arranged to carry drainage from the roof at least 5 feet
beyond the foundation walls and backfill zone. Should landscaping plants be located next
to the structure, we recommend the installation of plants that require minimal watering.
PAVEMENT THICKNESS RECOMMENDATIONS
In conjunction with the subsurface soils investigation, this office performed pavement
thickness designs for parking lot areas, main traffic corridors and truck loading areas.
These designs have been performed in accordance with the A.A.S.H.T.O. Guide For
Design of Pavement Structures, 1993 Software. A subgrade sample was obtained from
pavement subgrade�boring No. 4. This sample was classified revealing a liquid limit of 41,
plasticity index of 20 and a group index of 13. The sample classified as a sandy lean clay,
(A-7-6) type soils. A correlated R-Value of 5 was determined. Using this figure along with
an Equivalent Single Axle Loads (ESAL's) of 36,500 for parking lot areas and 54, 750 for
main traffic corridors, and overall standard deviation (50) of 0.44, a reliability of 75%, and
a terminal serviceability loss of 2.0, a structural number of parking areas of 2.29 and 2.44
for main traffic areas was calculated. Flexible pavement options are also based on Hot
Bituminous Pavement (H.B.P.) having an R-value of 95 or better and Aggregate Base
7
and taking responsibility for risks involved, a floating floor slab bearing on the native
materials may be a reasonable option.
If a floating slab option is pursued, it should be constructed to be "free-floating, " isolated
from all bearing members, utilities, and partition walls, door frames, cabinets, etc., so that
the slab can move unimpaired without producing architectural orstructural damage. Slabs
should be underlain with a 4-inch layer of washed rock to help distribute floor loads,
provide a capillary break, and provide a pathway for potential infiltrating water to be
directed toward sump areas. If moisture sensitive floor coverings are used on interior
slabs, consideration should be given to the use of barriers to minimize moisture rise
through the slab. Positive drainage should be provided for the excavation subgrade to
prevent pooling of water beneath the slab. At a minimum, concrete floor slabs should be
reinforced with 6" x 6" - W1.4 x W1.4 wire fabric, or equivalent. The slabs should be
jointed to a depth of at least 114 of the slab thickness in dimensions not to exceed 15 feet
or 225 square feet and at areas of potential cracking. Exterior slabs exposed to de-icing
chemicals or extreme weathering should be constructed using Type ll cement with higher
air contents.
BASEMENTS
Based on current groundwater levels, basement construction is deemed feasible at the
site. We do, however, require that all below grade habitable space be protected with a
perimeter drain system.
SITE GRADING, LANDSCAPING & DRAINAGE
Every precaution should be taken to prevent wetting of the foundation subsoils and the
percolation of water in the backfill zone or other areas that may reach the foundation or
slab elements. Water infiltrating near the foundation may result in architectural orstructural
damage due to consolidating or swelling of the subsoils. Backfill around the
ON
FLOOR SLABS
Below, we have provided the following table provided by the Colorado Association of
Geotechnical Engineers in their December 1996 report entitled, Guidelines for Slab
Performance Risk Evaluation and Residential Basement Floor System Recommendations.
This table can be used to evaluate potential slab risk with varying swell percentages. It
should be noted that all of our swell tests were performed using a 500 p.s.f. surcharge.
RECOMMENDED REPRESENTATIVE SWELL POTENTIAL
DESCRIPTIONS AND CORRESPONDING SLAB
PERFORMANCE RISK CATEGORIES
Slab Performance
Risk Category
Representative
Percent Swell
500 psf Surchar a
Representative
Percent Swell
10.00 psf Surcharge)
Low
0 to <3
0 to <2
Moderate
3 to <5
2 to <4
High
5 to <8
4 to <6
Very High
>8
>6
Note: The representative percent swell values presented are not necessarily measured
values; rather, they are a judgement of the swell of the soil and bedrock profile likely to
influence slab performance.
Based on our testing of the encountered materials, swell results fall within the low risk slab
performance category. However, movement is still possible if subgrade soils become
saturated. Therefore, we advise that a structural floor system with a void beneath it be
utilized if movement cannot be tolerated.
Another alternative would be to over -excavate 3 feet and replace the soil beneath the slab
with non -expansive structural fill. This would help to minimize slab heave. However, the
cost of these systems may be prohibitive. Therefore, with the owner/builder recognizing
5
The following requirements should be followed in the design of the foundation system:
9. All footings and pads should bear on or in the same type of soil or engineered fill.
Foundation elements and concrete floor slabs should not be placed on frozen
ground, topsoil, or inadequately compacted or unsuitable fill material. Where old
foundations are encountered and are removed, (existing house), backfill and
compaction procedures outlined in Appendix A shall be used.
2. All below grade habitable space should be protected by a properly installed
perimeter subdrain system around the exterior of the foundation. Crawl spaces
should also be protected with a subdrain system if ground water or site grading
conditions warrant installation.
3. Partition walls should not be placed directly on concrete floorslabs. They should be
suspended from the floor joists or roof assembly, or other approved methods that
will allow the slab to move vertically, unimpaired fora minimum vertical distance of
2 inches. Foundation elements shall be provided for all bearing walls. Bearing
walls should be isolated from the remaining concrete floor slab.
4. Based on the presence of soluble sulfates, a Type I -11 or Type 11 cement should be
used for all concrete exposed to the soils.
5. The bottom of all foundation components should be placed at least 3 feet above
subsurface water levels.
6. The completed open excavation should be observed by an experienced Soils
Engineer or technician, to confirm the subsurface conditions described in this report
and observe any variations which may affect construction at the site.
FOUNDATION RECOMMENDATIONS
The selection of the foundation type for a given situation and structure is governed by 2
basic considerations. First, the foundation elements must be designed to be safe against
shear failure in the underlying soils; and second, differential settlement or other vertical
movement of the foundation must be reduced to a reasonable level.
Two basic methods are available to us in selecting the foundation type and allowable
loads. These are the standard penetration test and consolidation -swell testing. Ultimately,
the bearing capacity of the foundation soil depends upon the size and shape of the
foundation element, the depth below the surface, and the physical characteristics of the
supporting soil.
Below we have provided design criteria for spread footings bearing on the native
undisturbed clays oron compacted engineered fills. The engineered fill can either consist
of native, onsite soils or granular structural fill. Engineered fills shall be constructed,
compacted and tested in accordance with Appendix A of this report.
Continuous Spread Footing Foundations
Where the foundation will be placed on the native undisturbed sandy lean clays, and at
least 3 feet above the high groundwater table, the foundation could be a continuous
spread footing foundation designed for a maximum allowable bearing capacity of 850
pounds per square foot (dead load plus half live load). If higher bearing capacities are
warranted, the foundation elements shall be over -excavated by 3-feet of depth and width
and replaced with compacted engineered fills. Where foundation elements will bear
entirely on these engineered fills, the maximum allowable bearing capacity may be
increased to 1750 p.s.f. with a 500 p.s.f. minimum dead load requirement. All footings
should be placed a minimum of 30 inches below finished grade for frost protection.
Foundation walls should be reinforced with rebarto span an unsupported length of 10 feet
or as required by the Foundation Engineer. Splicing and placement should comply with
ACI 318, ACI 332, or as required by the Foundation Engineer.
3
Undisturbed samples for use in the laboratory were taken in 3-inch O.D. thin wall Shelby
samplers, hydraulically pushed into the soil. Undisturbed and disturbed samples were
sealed in the field and preserved at natural moisture content until tested in the laboratory.
Complete logs of the boring operation are shown on the attached plates and include visual
classifications of each soil, location of subsurface changes, standard penetration test
results, and subsurface water level measurements at the time of this investigation.
LABORATORY TESTING
Laboratory tests were performed to determine visual classification, moisture contents, dry
densities, swelling and consolidation characteristics, plasticity, gradation and soluble
sulfates.
SUBSURFACE CONDITIONS
Subsurface strata was relatively uniform consisting of overburden sandy lean clay soils
with sand and gravel lenses to depths explored. Based on field and laboratory test data,
these materials offer low to moderately low bearing capacities while exhibiting minor swell
to consolidation potentials when subjected to a 500 p.s.f. wet surcharge.
At the time of this investigation and 72-hours later, free groundwater was noted at depths
ranging from 12.5 to 14 feet. These water levels should be anticipated to fluctuate
throughout the year and, therefore, may not be indicative of high groundwater levels.
2
SCOPE
The following report presents the results of a geotechnical investigation on a parcel of land
located at the Northeast corner of Timberline Road and Kechter Road, Fort Collins,
Colorado. The investigation was performed for The Frederickson Group, LLC. The
purpose of this investigation was to obtain the technical information and subsurface
property data necessary for the design and construction of a foundation for the proposed
Poudre Valley Congregation of the Jehovah's Witnesses. The conclusions and
recommendations presented in this report are based upon analysis of field and laboratory
data and experience with similar subsurface conditions in the general vicinity.
SITE DESCRIPTION
The subject site is located at the Northeast corner of Timberline Road and Kechter Road.
A single family residence presently occupies the relatively flat site.
FIELD INVESTIGATION
The field investigation consisted of 4 borings at selected locations on the site. The borings
were advanced with an Acker AD-11 drill rig utilizing 4-inch diameter continuous flight
augers.
As the boring operation advanced, an index of soils relative density and consistency was
obtained by use of the standard penetration test, ASTM Standard Test D-1586. The
penetration test results listed on the boring logs are the number of blows required to drive
the 2-inch diameter split -spoon sampler 12 inches, or increments as shown, into
undisturbed soil using a 140-pound hammer dropped 30 inches.
1
OLandmark ENGINEERING Ltd.
Engineers P I a it n e r s S it r v e y o r s A r c h i t e c t s G e o t e c h it i c a i
May 27, 2005
Project No. FREDEG-4J5F-02-709
The Frederickson Group
7711 Windsong Drive
Windsor, Colorado 80550
Dear Deanne:
The enclosed report presents the results of a geotechnical investigation at the Northeast corner
of Timberline Road and Kechter Road, Fort Collins, Colorado.
If you have any questions or if we can be of further assistance, please contact our office as soon
as possible.
Sincerely,
Landmark Engineering Ltd.
Larry!!/ M' ler
Geol ist
LA /tv
Enclosure
The above has been reviewed and approved under the direct supervision of
Colorado P.E. 35177.
�Gp REC�s
H T
2 3517
3521
Nest Eisenhower
Boitlevat'd
Loveland Colorado 80537
Loveland
(970) 667-6286
Fax (970) 667-6298
Memo (303) 629-7124
GEO TECHNICAL INVESTIGATION AT
NORTHEAST CORNER OF TIMBERLINE
ROAD & KECHTER ROAD,
FORT COLLINS, COLORADO
Prepared For:
The Frederickson Group LLC
7711 Windsong Drive
Windsor, Colorado 80550
May 27, 2005
Project No. FREDEG-4J5F-02-709
LANDMARK ENGINEERING LTD.
3521 W. EISENHOWER BLVD.
LOVELAND, CO 80537