HomeMy WebLinkAboutEAST RIDGE - PDP - 33-98D - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORT (3)Preliminary Geotechnical Engineering Report
TriTrend, Inc.
Terracon Project No. 20995028
Engineered fill should be placed and compacted in horizontal lifts, using equipment and
procedures that will produce recommended moisture contents and densities throughout
the lift. Recommended compaction criteria for engineered fill materials are as follows:
Material
Minimum Percent
(ASTM D698)
Scarified subgrade soils..........................................................................9.5
On -site and imported fill soils:
Beneath foundations ..................... .......:.................... .................. 95
Beneathslabs.............................................................................P5
Beneath pavements....................................................................95
Miscellaneous backfill (non-structural areas)..........................................90
On -site or imported clay soils should be compacted within a moisture content range of 2
percent below, to 2 percent above optimum. Imported granular soils should be
compacted within a moisture range of 3 percent below to 3 percent above optimum
unless modified by the project geotechnical engineer.
Shrinkage
For balancing grading plans, estimated shrink or swell of soils and bedrock when used
as compacted fill following recommendations in this report are as follows:
Material
Estimated Shrink(-) Swell (+)
Based on ASTM D698
On -site soils:
Clays............................................................................ A 5 to -20%
Excavation and Trench Construction
Excavations into the on -site soils will encounter a variety of conditions. Excavations into
the clays can be expected to stand on relatively steep temporary slopes during
construction. However, caving soils and groundwater may also be encountered. The
individual contractor(s) should be made responsible for designing and constructing
0
REPORT TERMINOLOGY
(Based on ASTM D653)
Expansive Potential The potential of a soil to expand (increase in volume) due to absorption of
moisture.
Finished Grade
The final grade created as a part of the project.
Footing
A portion of the foundation of a structure that transmits loads directly to the soil.
Foundation
The lower part of a structure that transmits the loads to the soil or bedrock.
Frost Depth
The depth of which the ground becomes frozen during the winter season.
Grade Beam
A foundation element or wall, typically constructed of reinforced concrete, used
to span between other foundation elements such as drilled piers.
Groundwater
Subsurface water found in the zone of saturation of soils, or within fractures in
bedrock.
Heave
Upward movement.
Lithologic
The characteristics which describe the composition and texture of soil and rock
by observation.
Native Grade
The naturally occuring ground surface.
Native Soil
Naturally occurring on -site soil, sometimes referred to as natural soil.
Optimum Moisture
The water content at which a soil can be compacted to a maximum dry unit
Content
weight by a given compactive effort.
Perched Water
Groundwater, usually of limited area maintained above a normal water elevation
by the presence of an intervening relatively impervious continuing stratum.
Scarify
To mechanically loosen soil or break down existing soil structure.
Settlement
Downward movement.
Skin Friction (Side
The frictional resistance developed between soil and an element of structure
Shear)
such as a drilled pier or shaft.
Soil (earth)
Sediments or other unconsolidated accumulations of solid particles produced by
the physical and chemical disintegration of rocks, and which may or may not
contain organic matter.
Strain
The change in length per unit of length in a given direction.
Stress
The force per unit area acting within a soil mass.
Strip
To remove from present location.
Subbase
A layer of specified material in a pavement system between the subgrade and
base course.
Subgrade
The soil prepared and compacted to support a structure, slab or pavement
system.
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REPORT TERMINOLOGY
(Based on ASTM D653)
Allowable Soil
The recommended maximum contact stress developed at the interface of the
Bearing Capacity
foundation element and the supporting material. -
Alluv/um
Soil, the constituents of which have been transported in suspension by flowing
water and subsequently deposited by sedimentation.
Aggregate Base
A layer of specified material placed on a subgrade or subbase usually beneath
Course
slabs or pavements.
Backf/l/
A specified material placed and compacted in a confined area.
Bedrock
A natural aggregate of mineral grains connected by strong and permanent
cohesive forces. Usually requires drilling, wedging, blasting or other methods of
extraordinary force for excavation.
Bench
A horizontal surface in a sloped deposit.
Caisson (Drilled pier
A concrete foundation element cast in a circular excavation which may have an
or Shaft)
enlarged base. Sometimes referred to as a cast -in -place pier or drilled shaft.
Coefficient of
A constant proportionality factor relating normal stress and the corresponding
Friction
shear stress at which sliding starts between the two surfaces.
Colluvium
Soil, the constituents of which have been deposited chiefly by gravity such as at
the foot of a slope or cliff.
Compaction
The densification of a soil by means of mechanical manipulation.
Concrete Slab -on-
A concrete surface layer cast directly upon a base, subbase or subgrade, and
Grade
typically used as a floor system.
Differentia/
Unequal settlement or heave between, or within foundation elements of a
Movement
structure.
Earth Pressure
The pressure or force exerted by soil on any boundary such as a foundation wall.
ESAL
Equivalent Single Axle Load, a criteria used to convert traffic to a uniform
standard, (18,000 pound axle loads).
Engineered Fill
Specified material placed and compacted to specified density and/or moisture
conditions under observations of a representative of a geotechnical engineer.
Equivalent Fluid
A hypothetical fluid having a unit weight such that it will produce a pressure
against a lateral support presumed to be equivalent to that produced by the actual
soil. This simplified approach is valid only when deformation conditions are such
that the pressure increases linearly with depth and the wall friction is neglected.
Existing Fill (or man-
Materials deposited through the action of man prior to exploration of the site.
made fi//)
Existing Grade
The ground surface at the time of field exploration.
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LABORATORY TESTS
SIGNIFICANCE AND PURPOSE
TEST
SIGNIFICANCE
PURPOSE
California
Used to evaluate the potential strength of subgrade soil,
Pavement
Bearing
subbase, and base course material, including recycled materials
Thickness
Ratio
for use in road and airfield pavements.
Design
Consolidation'
Used to develop an estimate of both the rate and amount of
Foundation
both differential and total settlement of a structure.
Design
Direct
Used to determine the consolidated drained shear strength of
Bearing Capacity,
Shear
soil or rock.
Foundation Design &
Slope Stability
Dry
Used to determine the in -place density of natural, inorganic,
Index Property
Density
fine-grained soils.
Soil Behavior
Expansion
Used to measure the expansive potential of fine-grained soil
Foundation & Slab
and to provide a basis for swell potential classification.
Design
Gradation
Used for the quantitative determination of the distribution of
Soil
particle sizes in soil.
Classification
Liquid &
Used as an integral part of engineering classification systems
Soil
Plastic Limit,
to characterize the fine-grained fraction of soils, and to specify
Classification
Plasticity index
the fine-grained fraction of construction materials.
Permeability
Used to determine the capacity of soil or rock to conduct a
Groundwater
liquid or gas.
Flow Analysis
pH
Used to determine the degree of acidity or alkalinity of a soil.
Corrosion
Potential
Resistivity
Used to indicate the relative ability of a soil medium to carry
Corrosion
electrical currents.
Potential
R-Value
Used to evaluate the potential strength of subgrade soil,
Pavement
subbase, and base course material, including recycled materials
Thickness
for use in road and airfield pavements.
Design
Soluble
Used to determine the quantitative amount of soluble sulfates
Corrosion
Sulphate
within a soil mass.
Potential
Unconfined
To obtain the approximate compressive strength of soils that
Bearing Capacity
Compression
possess sufficient cohesion to permit testing in the unconfined
Analysis
state.
for
Foundations
Water
Used to determine the quantitative amount of water in a soil
Index Property
Content
mass.
Soil Behavior
ROCK CLASSIFICATION
(Based on ASTM C-294)
Metamorphic Rocks
Metamorphic rocks form from igneous, sedimentary, or pre-existing metamorphic rocks in response
to changes in chemical and physical conditions occurring within the earth's crust after formation of
the original rock. The changes may be textural, structural, or mineralogic and may be accompanied
by changes in chemical composition. The rocks are dense and may be massive but are more
frequently foliated (laminated or layered) and tend to break into platy particles. The mineral
composition is very variable depending in part on the degree of metamorphism and in part on the
composition of the original rock.
Marble
A recrystallized medium- to coarse -grained carbonate rock composed of
calcite or dolomite, or calcite and dolomite. The original impurities are
present in the form of new minerals, such as micas, amphiboles, pyroxenes,
and graphite.
Metaquartzite
A granular rock consisting essentially of recrystallized quartz. Its strength
and resistance to weathering derive from the interlocking of the quartz grains.
Slate
A fine-grained metamorphic rock that is distinctly laminated and tends to split
into thin parallel layers. The mineral composition usually cannot be
determined with the unaided eye.
Schist
A highly layered rock tending to split into nearly parallel planes (schistose) in
which the grain is coarse enough to permit identification of the principal
minerals. Schists are subdivided into varieties on the basis of the most
prominent mineral present in addition to quartz or to quartz and feldspars; for
instance, mica schist. Greenschist is a green schistose rock whose color is
due to abundance of one or more of the green minerals, chlorite or amphibole,
and is commonly derived from altered volcanic rock.
Gneiss One of the most common metamorphic rocks, usually formed from igneous or
sedimentary rocks by a higher degree of metamorphism than the schists. It is
characterized by a layered or foliated structure resulting from approximately
parallel lenses and bands of platy minerals, usually micas or prisms, usually
amphiboles, and of granular minerals, usually quartz and feldspars. All
intermediate .varieties between gneiss and schist and between gneiss and
granite are often found in the same areas in which well-defined gneisses
occur.
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ROCK CLASSIFICATION
(Based on ASTM C-294)
Igneous Rocks
Igneous rocks are formed by cooling from a molten rock mass (magma). Igneous rocks are divided
into two classes (1) plutonic, or intrusive, that have cooled slowly within the earth; and (2)
volcanic, or extrusive, that formed from quickly cooled lavas. Plutonic rocks have grain sizes
greater than approximately 1 mm, and are classified as coarse- or medium -grained. Volcanic rocks
have grain sizes less than approximately 1 mm, and are classified as fine-grained. Volcanic rocks
frequently contain glass. Both plutonic and volcanic rocks may consist of porphyries that are
characterized by the presence of large mineral grains in a fine-grained or glassy groundmass. This
is the result of sharp changes in rate of cooling or other physico-chemical conditions during
solidification of the melt.
Granite Granite is a medium- to coarse -grained light-colored rock characterized by the
presence of potassium feldspar with lesser amounts of plagioclase feldspars
and quartz. The characteristic , potassium feldspars are othoclase or
microcline, or both; the common plagioclase feldspars are albite and
oligoclase. Feldspars are more abundant than quartz. Dark -colored mica
(biotite) is usually present, and light-colored mica (muscovite) is frequently
present. Other dark -colored ferromgnesian minerals, especially hornblende,
may be present in amounts less than those of the light-colored constituents.
Quartz-Monzonite Rocks similar to granite but contain more plagioclase feldspar than potassium
and Grano -Diorite feldspar.
Basalt Fine-grained extrusive equivalent of gabbro and diabase. When basalt
contains natural glass, the glass is generally lower in silica content than that
of the lighter -colored extrusive rocks.
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ROCK CLASSIFICATION
(Based on ASTM C-294)
Sedimentary Rocks
Sedimentary rocks are stratified materials laid down by water or wind. The sediments may be
composed of particles of pre-existing rocks derived by mechanical weathering, evaporation or by
chemical or organic origin. The sediments are usually indurated by cementation or compaction.
Chert Very fine-grained siliceous rock composed of micro -crystalline or crypto-
crystalline quartz, chalcedony or opal. Chart is various colored, porous to
dense, hard and has a conchoidal to splintery fracture.
Claystone Fine-grained rock composed of or derived by erosion of silts and clays or any
rock containing clay. Soft massive; gray, black, brown, reddish or green and
may contain carbonate minerals.
Conglomerate Rock consisting of a considerable amount of rounded gravel, sand and
cobbles with or without interstitial or cementing material. The cementing or
interstitial material may be quartz, opal, calcite, dolomite, clay, iron oxides or
other materials.
Dolomite A fine-grained carbonate rock consisting of the mineral dolomite (CaMg
(CO3)21. May contain noncarbonate impurities such as quartz, chert, clay
minerals, organic matter, gypsum and sulfides. Reacts with hydrochloric acid
(HCL).
Limestone A fine-grained carbonate rock consisting of the mineral calcite (CaCO3). May
contain noncarbonate impurities such as quartz, chert, clay minerals, organic
matter, gypsum and sulfides. Reacts with hydrochloric acid (HCL).
Sandstone Rock consisting of particles of sand with or without interstitial and cementing
materials. The cementing or interstitial material may be quartz, opal, calcite,
dolomite, clay, iron oxides or other material.
Shale Fine-grained rock composed of, or derived by erosion of silts and clays or any
rock containing clay. Shale is hard, platy, or fissile may be gray, black,
reddish or green and may contain some carbonate minerals (calcareous
shale).
Siltstone Fine grained rock composed of, or derived by 'erosion of silts or rock
containing silt. Siltstones consist predominantly of silt sized particles
(0.0625 to 0.002 mm in diameter) and are intermediate rocks between
claystones and sandstones, may be gray, black, brown, reddish or green and
may contain carbonate minerals.
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UNIFIED SOIL CLASSIFICATION SYSTEM
Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests"
Coarse -Grained
Soils more than
50% retained an
No. 200 sieve
Gravels more than
50% of coarse
fraction retained on
No. 4 sieve
Soil Classification
Group a
iymbol Group Name
Clean Gravels Less Cu > 4 and 1 < Cc <3E GW Well -graded ravel'
than 5% fines g g
Cu < 4 and/or 1 > Cc > 3E
-Gravels with Fines Fines classify as ML or MH GIM Silt
more than 12% finest Y y gravel,G,H
Sands 50% or more Clean Sands Less
of coarse fraction than 5% fines°
passes No. 4 sieve
Fines classify as CL or CH
Cu> 6and 1 <Cc <3'
Cu < 6 and/or 1 > Cc > 3E
Sands with Fines Fines classify as ML or MH
GC
SW
SP
SM
Well -graded sand'
Poorly graded sand'
Silty sand°•"''
more than 12% fines°
- --
Fines Classify as CL or CH
Sc Clayey sando"'
Fine -Grained Soils Silts and Clays
inorganic PI > 7 and plots on or above "A line' -CL Lean clay'"'
50% or more Liquid limit less
passes the than 50
PI < 4 or plots below "A"
line' ML Silt"-`--"
No. 200 sieve
organic Liquid limit - oven dried
Organic clayl.L"A
< 0.75 OL
Liquid limit - not dried
Organic silt`•"-O
Silts and Clays
inorganic PI plots on or above "A" line CH Fat clay'-L'
Liquid limit 50
or more
PI lots below "A" line
MH Elastic Siltl*L,l
organic Liquid limit - oven dried
Organic clay"-`"
< 0.75 OH
Liquid limit - not dried
Organic siltK'L.".o
Highly organic soils Primarily
organic matter, dark in color, and organic odor
PT Peat
A9ased on the material passing the 3-in.
Wf soil contains 15 to 290,16 plus No. 200, add
(75-mm) sieve
.sCu"D /D Cc (�'_ '
e' 30 To
with sand" or "with gravel", whichever is
'If field sample contained cobbles or
x DEo
predominant.
boulders, or both, add "with cobbles or
`If soil contains > 30% plus No. 200
boulders, or both" to group name.
predominantly sand, add "sandy" to group
'Gravels with 5 to 12% fines require dual
Flf soil contains > 15% sand, add "with
name.
symbols:
sand" to group name.
'"If soil contains > 30% plus No. 200,
GW-GM well -graded gravel with silt
'If fines classify as CL-ML, use dual symbol
predominantly gravel, add "gravelly" to group
GW-GC well -graded gravel with clay
GC -GM, or SC-SM.
name.
GP -GM poorly graded gravel with silt
"If fines are organic, add "with organic fines"
"PI > 4 and plots on or above "A" line.
GP -GC poorly graded gravel with clay
to group name.
oPl < 4 or plots below "A" line.
'Sands with 5 to 12% fines require dual
'If soil contains > 15% gravel, add "with
'PI plots on or above "A" line.
symbols:
gravel" to group name.
'PI plots below "A" line.
SW-SM well -graded sand with silt
'If Atterberg limits plot in shaded area, soil is
SW -SC well -graded sand with clay
a CL-ML, silty clay.
SP-SM poorly graded sand with silt
SP-SC poorly graded sand with clay
so
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LIQUID LIMIT (LL
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DRILLING AND EXPLORATION
DRILLING & SAMPLING SYMBOLS:
SS : Split Spoon - 1 " I.D., 2" O.D., unless otherwise noted
PS : Piston Sample
ST : Thin -Walled Tube - 2" O.D., unless otherwise noted
WS : Wash,Sample
R : Ring Barrel Sampler - 2.42" I.D., 3" O.D. unless otherwise noted.
PA : Power Auger
FT : Fish Tail Bit
HA: Hand Auger
RB : Rock Bit
DB : Diamond Bit
BS : Bulk Sample
AS : Auger Sample
PM : Pressure Meter
HS : Hollow Stem Auger
DC : Dutch Cone
WE: Wash Bore
Penetration Test: Blows per foot of a 140 pound hammer falling 30 inches on a 2-inch O.D. split spoon, except where noted.
WATER LEVEL MEASUREMENT SYMBOLS:
WL : Water Level WS :While Sampling
WCI : Wet Cave in WD : While Drilling
DCI : Dry Cave in BCR : Before Casing Removal
AB :After Boring ACR : After Casting Removal
Water levels indicated on the boring logs are the levels measured in the borings at the time indicated. In pervious soils, the
indicated levels may reflect the location of groundwater. In low permeability soils, the accurate determination of groundwater
levels is not possible with only, short term observations.
DESCRIPTIVE SOIL CLASSIFICATION
PHYSICAL PROPERTIES OF BEDROCK
Soil Classification is based on the Unified Soil Classification
DEGREE OF WEATHERING:
system and the ASTM Designations D-2487 and D-2488.
Coarse Grained Soils have more than 50% of their dry
Slight
Slight decomposition of parent material on
weight retained on a #200 sieve; they are described as:
joints. May be color change.
boulders, cobbles, gravel or sand. Fine Grained Soils have
less than 50% of their dry weight retained on a #200 sieve;
Moderate
Some decomposition and color change
they are described as: clays, if they are plastic, and silts if
throughout.
they are slightly plastic or non -plastic. Major constituents
may be added as modifiers and minor constituents may be
High
Rock highly decomposed, may be extremely
added according to the relative proportions based on grain
broken.
size. In addition to gradation, coarse grained soils are
defined on the basis of their relative in -place density and
HARDNESS AND DEGREE OF CEMENTATION:
fine grained soils on the basis of their consistency.
Limestone and Dolomite:
Example: Lean clay with sand, trace gravel, stiff (CL); silty
Hard
Difficult to scratch with knife.
sand, trace gravel, medium dense ISM).
Moderately
Can be scratched easily with knife,
CONSISTENCY OF FINE-GRAINED SOILS
Hard
Cannot be scratched with fingernail.
Unconfined Compressive
Soft
Can be scratched with fingernail.
Strength, Qu, psf Consistency
Shale, Siltstone and Claystone;
< 500 Very Soft
Hard
Can be scratched easily with knife, cannot
500 - 1,000 Soft
be scratched with fingernail.
1,001 - 2,000 Medium
2,001 - 4,000 Stiff
Moderately
Can be scratched with fingernail.
4,001 - 8,000 Very Stiff
Hard
8,001 - 16,000 Very Hard
Soft
Can be easily dented but not molded with
RELATIVE DENSITY OF COARSE -GRAINED SOILS:
fingers.
N-Blows/ft Relative Density
0-3 Very Loose
Sandstone and Conglomerate:
4-9 Loose
Well
Capable of scratching a knife blade.
10-29 Medium Dense
Cemented
30-49 Dense
50-80 Very Dense
Cemented
Can be scratched with knife.
80 + Extremely Dense
Poorly
Can be broken apart easily with fingers.
Cemented
Ireirracon
DRILLING AND EXPLORATION
DRILLING & SAMPLING SYMBOLS:
R : Ring Barrell - 2.42" I.D., 3" O.D., unless otherwise noted
SS : Split Spoon - 1_" I.D., 2" O.D., unless otherwise noted
PS : Piston Sample
ST : Thin -Walled Tube - 2" O.D., unless otherwise noted
WS : Wash Sample
PA: Power Auger
FT : Fish Tail Bit
HA: Hand Auger
RB : Rock Bit
DB : Diamond Bit = 4", N, B
BS : Bulk Sample
AS : Auger Sample
PM : Pressure Meter
HS : Hollow Stem Auger
DC: Dutch Cone
WB : Wash Bore
Penetration Test: Blows per foot of a 140 pound hammer falling 30 inches on a 2-inch O.D. split spoon, except where
noted.
WATER LEVEL MEASUREMENT SYMBOLS:
WL :Water Level
WS :While Sampling
WCI : Wet Cave in
WD : While Drilling
DCI : Dry Cave in
BCR : Before Casing Removal
AB : After Boring
ACR : After Casting Removal
Water levels indicated on the boring logs are the levels measured in the borings at the time indicated. In pervious soils,
the indicated levels may reflect the location of groundwater. In low permeability soils, the accurate determination of
groundwater levels is not possible with only short term observations.
DESCRIPTIVE SOIL CLASSIFICATION:
Soil Classification is based on the Unified Soil Classification system and the ASTM Designations D-2487 and D-2488.
Coarse Grained Soils have more than 50% of their dry weight retained on a #200 sieve; they are described as: boulders,
cobbles, gravel or sand. Fine Grained Soils have less than 50% of their dry weight retained on a #200 sieve; they are
described as: clays, if they are plastic, and silts if they are slightly plastic or non -plastic. Major constituents may be
added as modifiers and minor constituents may be added according to the relative proportions based on grain size. In
addition to gradation, coarse grained soils are defined on the basis of their relative in -place density and fine grained soils
on the basis of their consistency. Example: Lean clay with sand, trace gravel, stiff (CL); silty sand, trace gravel, medium
dense ISM).
CONSISTENCY OF FINE-GRAINED SOILS:
Unconfined Compressive
Strength, Qu, psf
Consistency
< 500
Very Soft
500 - 1,000
Soft
1,001 - 2,000
Medium
2,001 - 4,000
Stiff
4,001 - 8,000
Very Stiff
8,001-16,000
Very Hard
RELATIVE PROPORTIONS OF
SAND AND GRAVEL
Descriptive Term(s)
(of Components Also
Percent of
Present in Sample)
Dry Weight
Trace
< 15
With
15 - 29
Modifier
> 30
RELATIVE PROPORTIONS OF FINES
Descriptive Term(s)
(of Components Also
Percent of
Present in Sample)
Dry Weight
Trace
< 5
With
5-12
Modifier
> 12
RELATIVE DENSITY OF
COARSE -GRAINED SOILS:
N-Blows/ft. Relative Density
0-3
Very Loose
4-9
Loose
10-29
Medium Dense
30-49
Dense
50-80
Very Dense
80+
Extremely Dense
GRAIN SIZE TERMINOLOGY
Major Component
of Sample
Size Range
Boulders
Over 12 in. (300mm)
Cobbles
12 in, to 3 in.
(300mm to 75mm)
Gravel
3 in. to #4 sieve
(75mm to 4.75mm)
Sand
#4 to #200 sieve
(4.75mmto 0.075mm)
Silt or Clay
Passing #200 Sieve
(0.075mm)
APPENDIX C
Marr a-r:o
0.47
0.46
0.45
0.44
V 0.4,
O
I
D
R 0.4:
A
T
I
O
0.41
0.4(
0.3!
W&I
0.3'
0.3
APPLIED PRESSURE, TSF
Boring and depth (ft.) Classificadon DD MC %
101 3 7.0 1 Sandy Lean Clay . 115 13
PROJECT 160-Acre Ryland Parcel - S/E/C of E. Vme JOB NO. zuyy5uzb
Dr. & Summit View Rd. DATE 3/24/99
CONSOLIDATION TEST
TERRACON
S
w
E
L
L
U
C
O
N
S
O
L
I
D
A
T
I
O
N
u
it
APPLIED PRESSURE, TSF
Boring and depth (ft.) Classification DD MC%
101 3 7.0 Sandy Lean Clay. 115 13
PROJECT 160-Acre Ryland Parcel - S/E/ of ._ VinP JOB NO. 20995028
Dr. & Summit View Rd. DATE 3/24/99
CONSOLIDATION TEST
TERRACON
0.44
0.43
0.0
0.41
0.4(
I
D 0.35
R
A
T
1 0.31
O
0.3'
0.31
0.1
0.3-
0.3
0.3
APPLIED PRESSURE, TSF
Boring and depth (ft.) Classification DD MC %
101 2 3.0 1 Sandy Lean Clay 118 16
PROJECT 160-Acre Ryland Parcel - S/ /C of E Vine JOB NO. ZuMuz
Dr. & Summit View Rd. DATE 3/24/99
CONSOLIDATION TEST
TERRACON
S
w
E
L
L
�a
C
O
N
S
O
L
I
D
A
T
I
O
N
4
3
2
i
01
1
2
3
4
5
6
0.1 t 10
APPLIED PRESSURE, TSF
Boring and depth (ft.) Classification DD MC%
101 2 3.0 1 Sandv Lean Clav . 118 1 16
PROJECT 160-Acre Ryland Parcel - S/E/C of E. Vine JOB NO. 20995028
Dr. & Summit View Rd. DATE 3/24/99
CONSOLIDATION TEST
TERRACON
APPENDIX B
LOG OF TEST BORING NO. 5
Page 1 of 1
CLIENT
ARCHITECT ENGINEER
TriTrend
Big Horn Resources, Inc.
SITE S/E/C of E. Vine Dr. & Summit View Rd.
PROJECT
Fort Collins, Colorado
160-Acre Ryland Parcel
SAMPLES
TESTS
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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
Irefr��®�
BORING STARTED 799
g 14.0' W.D.
=None A.B.
RING COMPLETED
WL
RIG CME-55
FOREMAN RTS
�'I
Water checked 3 days A.B.
APPROVED DAR
JOB # 20995028
LOG OF TEST BORING NO. 4 Page 1 of 1
CLIENT
TriTrend
ARCHITECT / ENGINEER
Big Horn Resources, Inc.
SITE S/E/C of E. Vine Dr. & Summit View Rd.
Fort Collins Colorado
PROJECT
160-Acre Ryland Parcel
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16
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SILTY SAND
15.0 Red, moist, medium dense U-4930.0
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11
20
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
Irerracon
BORING STARTED 3-1-99
s 14.5' W.D.
t None A.B.
COMPLETED
�
RIGCME 5
FottEN1AN-99 RTS
µ'I
Water checked 3 da s A.B.
APPROVED DAR
JOB s 20995028
LOG OF TEST BORING NO. 3 Page 1 of 1
CLIENT
ARCHITECT/ENGINEER
TriTrend
Big Horn Resources, Inc.
SITE S/E/C of E. Vine Dr. & Summit View Rd.
PROJECT
Fort Collins, Colorado
160-Acre Ryland Parcel
SAMPLES
TESTS
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12"
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112
2990
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12"
28
16
20
25.0 4925.0
25
8
SS
12"
20
11
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
Arerracon
BORING STARTED 3-1-99
WL
g 17.0' W.D.IT
15.5' A.B.ORING
COMPLETED 3-1-99
WL
RIG CME-55
FOREMAN RTS
WL
Water checked 3 days A.B.
APPROVED DAR
JOB a 20995028
LOG OF TEST BORING NO. 2 Page 1 of 1 MON
CLIENT
ARCHITECT / ENGINEER
TriTrend
Big Horn Resources, Inc.
SITE S/E/C of E. Vine Dr. & Summit View Rd.
PROJECT
Fort Collins Colorado
160-Acre Ryland Parcel
SAMPLES
TESTS
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2
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12"
16
110
3870
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6
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12"
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121
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5
22
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
rerr a c ®n
BORING STARTED 3-1-99
WL
g 11.0, W.D.
= None A.B.
BORING COMPLETED 3-1-99
WL
RIG CME-55
FOREMAN RTS
L
Water checked 3 days A.B.
APPROVED DAR
JOB a 20995028
LOG OF TEST BORING NO. 1 Page 1 of 1
CLIENT
ARCHITECT / ENGINEER
TriTrend
Big Horn Resources, Inc.
SITE S/E/C of E. Vine Dr. & Summit View Rd.
PROJECT
Fort Collins, Colorado
160-Acre Ryland Parcel
SAMPLES
TESTS
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12"
7
13
V.
2.5 Brown, dry to moist 4952.5
Medium
CLAYEY SAND
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2
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12'
7
104
6120
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3
SS
12"
9
8
5
6.0 4949.0
SANDY LEAN CLAY
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4
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12"
9
109
4450
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5
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12"
5
18
10
12.5 4942.5
15
SILTY SAND
Red, moist, medium dense
15.0 4940.0
SM
6
SS
12"
13
2
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
� r�rr �c®n
BORING STARTED 3-1-99
None w.D.
=None A.B.
RING COMPLETED 99
WL
Ig
RIGCME -55
FOREMAN RTS
L
Water checked 3 days A.B.
APPROVED DAR
JOB s 20995028
EAST VINE DRIVE
- -
- - -
- - - - - - - - - - - -
- -
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-----____-_-_---__--_-J
DIAGRAM IS FOR GENERAL LOCATION ONLY,
AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES.
N
f
FIGURE I: SITE PLAN
160-ACRE RYLAND PARCEL
SE CORNER OF E. VINE DR. AND SUMMITT VIEW RD.
FORT COLLINS, COLORADO
Project Mngr.
DAR
Irerracon
301 N. HOWES STREET
FORT COLUNS, CaARADD e0521
Project No.20
Designed Dy: DAR
Scale.
Checked Br' DAR -
Data: 3-
Approved ey: DAR
Drawn Or.
Dle Name:
28SLD
Figure No.
1
APPENDIX A
Preliminary Geotechnical Engineering Report
TriTrend, Inc.
Terracon Project No. 20995028
GENERAL COMMENTS
It should be noted this was a preliminary investigation and the foundation systems
recommended in this report are based on preliminary tests. Due to variations in soil conditions
encountered at the site, it is recommended that additional test borings be made prior to final
design. Samples obtained from the borings should be tested in the laboratory to provide a
basis for evaluating subsurface conditions.
This report has been prepared for the exclusive use of our client for specific application to the
project discussed and has been prepared in accordance with generally accepted geotechnical
engineering practices. No warranty, express or implied, is made. This report has been
prepared to aid in the evaluation of the property and to assist the architect and/or engineer in
the preliminary design of this project.
This report is for the exclusive purpose of providing preliminary 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.
10
Preliminary Geotechnical Engineering Report
TriTrend, Inc.
Terracon Project No. 20995028
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.
The soils to be penetrated by the proposed excavations may vary significantly across
the site. The preliminary soil classifications are based solely on the materials
encountered in widely spaced exploratory test borings. The contractor should verify that
similar conditions exist throughout the proposed area of excavation. If different
subsurface conditions are encountered at the time of construction, the actual conditions
should be evaluated to determine any excavation modifications necessary to maintain
safe conditions.
As a safety measure, it is recommended that all vehicles and soil piles be kept to a
minimum lateral distance from the crest of the slope equal to no less than the slope
height. The exposed slope face should be protected against the elements.
Additional Design and Construction Considerations
Underground Utility Systems
All piping should be adequately bedded for proper load distribution. It is suggested that
clean, graded gravel compacted to 75 percent of Relative Density ASTM D4253 be
used as bedding. 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 soils or imported materials approved by the geotechnical engineer. The pipe
backfill should be compacted to a minimum of 95 percent of Standard Proctor Density
ASTM D698.
Surface Drainage
Positive drainage should be provided during construction and maintained throughout the
life of the proposed project. Infiltration of water into utility or foundation excavations
must be prevented during construction. In areas where sidewalks or paving do not
immediately adjoin the structure, we recommend that protective slopes be provided with
a minimum grade of approximately 5 percent for at least 10 feet from perimeter walls.
l;'7
Preliminary Geotechnical Engineering Report
TriTrend, Inc.
Terracon Project No. 20995028
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. Lightweight excavation equipment may be required to reduce subgrade
pumping.
Subgrade Preparation
Subgrade soils beneath interior and exterior slabs, and beneath pavements should be
scarified, moisture conditioned and compacted to a minimum depth of 8 inches. The
moisture content and compaction of subgrade soils should be maintained until slab or
pavement construction.
Fill Materials and Placement
Clean on -site soils or approved imported materials may be used as fill material.
On -site soils are not recommended for use as compacted fill beneath interior or exterior
floor slabs.
Imported soils (if required) should conform to the following:
Gradation
Percent fines by weight
(ASTM C136)
6"............................................................................................................100
3".....................................................................................................7.0-100
No. 4 Sieve......................................................................................50-100
No. 200 Sieve......................................:........................................7.0 (max)
• Liquid Limit.......................................................................35 (max)
• Plasticity Index..................................................................1.5 (max)
rA
Preliminary Geotechnical Engineering Report
TriTrend, .Inc.
Terracon Project No. 20995028
Site Preparation
Strip and remove existing vegetation, debris, and other deleterious materials from
proposed building and pavement areas. All exposed surfaces should be free of mounds
and depressions which could prevent uniform compaction.
Stripped materials consisting of vegetation and organic materials should be wasted from
the site, or used to revegetate landscaped areas or exposed slopes after completion of
grading operations. If it is necessary to dispose of organic materials on -site, they should
be placed in non-structural areas, and in fill sections not exceeding 5 feet in height.
The site.should be initially graded to create a relatively level surface to receive fill, and to
provide for a relatively uniform thickness of fill beneath proposed building structures.
All exposed areas which will receive fill, once properly cleared and benched where
necessary, should be scarified to a minimum depth of eight inches, conditioned to near
optimum moisture content, and compacted.
Although evidence of fills or underground facilities such as septic tanks and cesspools
was not observed during the site reconnaissance, such features could be encountered
during construction. These facilities probably exist at the old house along Summit View
Drive. If unexpected fills or underground facilities are encountered, such . features
should be removed and the excavation thoroughly cleaned prior to backfill placement
and/or construction.
It is anticipated that excavations for the proposed construction can be accomplished
with conventional earthmoving equipment.
Depending upon depth of excavation and seasonal conditions, groundwater may be
encountered in excavations on the site. Pumping from sumps may be utilized to control
water within excavations.
Based upon the subsurface conditions determined from the geotechnical exploration,
subgrade soils exposed during construction are anticipated to be relatively stable.
However, the stability of the subgrade may be affected by precipitation, repetitive
construction traffic or other factors. If unstable conditions develop, workability may be
improved by scarifying and drying. Overexcavation of wet zones and replacement with
granular materials may be necessary. Use of lime, fly ash, kiln dust, cement or
R
Preliminary Geotechnical Engineering Report
TriTrend, Inc.
Terracon Project No. 20995028
The following foundation systems were evaluated for use on the site:
• spread footings and/or grade beams bearing on undisturbed soils;
• spread footings and/or grade beams bearing on engineered fill
Foundation Systems - Spread Footings
Due to the presence of low -swelling overburden soils on the site, spread footing foundations
bearing upon undisturbed subsoils and/or engineered fill are recommended for support for the
proposed structures. Based on preliminary test results, the footings may be designed for a
maximum bearing pressure of between 1500 to 2500 psf. In addition, the footings should be
sized to maintain a minimum dead -load pressure of between 250 to 750 psf. The design
bearing pressure applies to dead loads plus design live load conditions.
Basement Construction
Basement construction is feasible providing the finished basement slabs are placed at least 3
feet above groundwater levels and complete dewatering systems are placed around all lower
basement areas. Slab -on -grade construction is considered acceptable for use, provided that
design and construction recommendations are followed.
Floor Slab Design and Construction
Some differential movement of a slab -on -grade floor system is possible should the subgrade
soils become elevated in moisture content. To reduce potential slab movements, the subgrade
soils should be prepared as outlined in the "Earthwork" section of this report.
Earthwork
• General Considerations
The following presents recommendations for site preparation, excavation, subgrade
preparation and placement of engineered fills on the project.
All earthwork on the project should be observed and evaluated by Terracon. The
evaluation of earthwork should include observation and testing of engineered fill,
subgrade preparation, foundation bearing soils, and other geotechnical conditions
exposed during the construction of the project.
5
Preliminary Geotechnical Engineering Report
TriTrend, Inc.
Terracon Project No. 20995028
Mapping completed by the Colorado Geological Survey ('Hart, 1972), indicates the site in an
area of "Moderate Swell Potential". Potentially expansive materials mapped in this area include
bedrock, weathered bedrock and colluvium (surficial units).
Soil and Bedrock Conditions
The site is overlain by cultivated silty topsoil which has been penetrated by root growth and
organic matter. The topsoil is underlain by lean clay with sand, sandy lean clay, and clayey
sand layers which extend to silty sand or well graded sand. The clays are medium to stiff and
moist in -situ.
Field and Laboratory Test Results
Field and laboratory test results indicate that the clay soils exhibit low to, Swell potential and. low
to moderate bearing characteristics.
Groundwater Conditions
Groundwater was encountered in four of the test borings at approximate depths of 11 to 17 feet
below existing site grade at the time of field exploration. When checked three days after drilling,
four of the test borings were measured dry to the depths explored.. Groundwater was measured
at approximately 16 feet below existing grade in the remaining test boring. The groundwater is
near the surface in the depression at the south central part of thesite. These observations
represent groundwater conditions at the time of the field exploration, 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.
PRELIMINARY ENGINEERING ANALYSES AND RECOMMENDATIONS
Geotechnical Considerations
The site appears suitable for the proposed construction from ageotechnical engineering point
of view. Potentially expansive soils at the site will require particular attention in the design and
construction.
'Hart, Stephen S., 1972, Potentially Swelling Soil and Rock in the Front Range Urban Corridor, Colorado, Colorado
Geological Survey, Environmental Geology No. 7.
4
Preliminary Geotechnical Engineering Report
TriTrend, Inc.
Terracon Project No. 20995028
foundation and earthwork recommendations. All laboratory tests were performed in general
accordance with the applicable ASTM, local or other accepted standards.
Selected soil samples were tested for the following engineering properties:
• Water Content
• Dry Density
• Consolidation
Expansion
SITE CONDITIONS
• Liquid Limit
• Plasticity Index
• Percent Fines
The site consists of a vacant, undeveloped, cultivated 160-acrefarm land parcel. The property
is relatively flat with a depression roughly at the center of the. site. Surface drainage is generally
to the south except near the depression. The site is bordered to the north by Vine Drive and the
Burlington Northern Railroad tracks, out buildings and Summit View Drive to the west, vacant
farm land to the east, and a gravel pit to the south. Several stockpiles of asphalt, concrete,
sand, and gravel exist on the site.
SUBSURFACE CONDITIONS
Geology
The proposed area is located within the Colorado
physiographic province
Piedmont section of the Great Plains
formed during Late Tertiary and Early
quaternary time (approximately 2,000,000 years ago), is a broad, erosional trench which
separates the Southern Rocky Mountains from the High Plains. Structurally, the site lies along
the western flank of the Denver Basin. During the Late Mesozoic and Early Cenozoic Periods
(approximately 70,000,000 years ago), intense tectonic activity occurred, causing the uplifting of
the Front Range and associated downwarping of the Denver Basin to the east. Relatively flat
uplands and broad valleys characterize the present-day topography of the Colorado Piedmont
in this region. The site is underlain by the Cretaceous Pierre Formation at depths typically
greater than 25 feet below the surface. The bedrock is overlain. by alluvial sands and eolian
clays of Pleistocene and/or Recent Age.
The Colorado Piedmont,
3
Preliminary Geotechnical Engineering Report
TriTrend, Inc.
Terracon Project No. 20995028
SITE EXPLORATION
The scope of the services performed for this project included a site reconnaissance by a
geotechnical engineer, a subsurface exploration program, laboratory testing and engineering
analyses.
Field Exploration
A total of five (5) test borings were drilled on March 1, 1999 to approximate depths of 15 to 25
feet below existing site grades at the locations shown on the Site Plan, Figure 1. The borings
were advanced with a truck -mounted drilling rig, utilizing 4-inch diameter solid stem augers.
The borings were located in the field by pacing from property lines and/or existing site features.
The accuracy of boring locations should only be assumed to the level implied by the methods
used.
Continuous lithologic logs of each boring were recorded by the geotechnical engineer during the
drilling operations. At selected intervals, samples of the subsurface materials were taken by
means of pushing thin -walled Shelby tubes, or by driving split -spoon samplers.
Penetration resistance measurements were obtained by driving the split -spoon into the
subsurface materials with a 140-pound hammer failing 30 inches. The penetration resistance
value is a useful index in estimating the consistency, relative density or hardness of the
materials encountered.
Groundwater conditions were evaluated in each boring at the time of site exploration, and two to
seven days after drilling.
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. 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.
Laboratory tests were conducted on selected soil samples and are presented in Appendix B.
The test results were used for the geotechnical engineering analyses, and the development of
2
PRELIMINARY GEOTECHNICAL ENGINEERING REPORT
160 ACRE RYLAND PARCEL
NE'/a OF SECTION 8, TOWNSHIP 7 NORTH, RANGE 68 WEST
SOUTHEAST CORNER OF EAST VINE DRIVE AND SUMMIT VIEW DRIVE
FORT COLLINS, COLORADO
TERRACON PROJECT NO. 20995028
MARCH 25, 1999
INTRODUCTION
This report contains the results of our geotechnical engineering exploration for the proposed
160-acre development to be located at the southeast corner of East Vine Drive and Summit
View Drive in Fort Collins, Colorado. The site is located in the Northeast 1/4 of Section 8,
Township 7 North, Range 68 West of the 6th Principal Meridian.
The purpose of these services is to provide information and preliminary geotechnical
engineering recommendations relative to:
• subsurface soil and bedrock conditions
• groundwater conditions
• foundation design and construction
• basement construction
• floor slab design and construction
• earthwork
• drainage
The recommendations contained in this report are based upon the results of field and laboratory
testing, engineering analyses, and experience with similar soil conditions, structures and our
understanding of the proposed project.
PROPOSED CONSTRUCTION
Based on information provided by Gary L. Kounkel of Big Horn Resources, the proposed
development is to consist of residential structures.
Preliminary Geotechnical Engineering Report
TriTrend, Inc.
Terracon Project No. 20995028
TABLE OF CONTENTS (Cont'd)
APPENDIX A
Site. Plan
Logs of Borings
APPENDIX B
Laboratory Test Results
APPENDIX C
General Notes
iv
Preliminary Geotechnical Engineering Report
TriTrend, Inc.
Terracon Project No. 20995028
TABLE OF CONTENTS
Page No.
Letterof Transmittal............................................................................................................... i
INTRODUCTION...................................................................................................................1
PROPOSED CONSTRUCTION............................................................................................1
SITEEXPLORATION...........................................................................................................2
FieldExploration..........................................................................................................2
LaboratoryTesting.......................................................................................................2
SITECONDITIONS...............................................................................................................3
SUBSURFACECONDITIONS..............................................................................................3
Geology....................................................................................................................... 3
Soil and Bedrock Conditions........................................................................................4
Field and Laboratory Test Results...............................................................................4
Groundwater Conditions..............................................................................................4
PRELIMINARY ENGINEERING ANALYSES AND RECOMMENDATIONS .........................4
Geotechnical Considerations.......................................................................................4
Foundation Systems - Spread Footings ............................... :....................................... 5
Basement Construction................................................................................................ 5
Floor Slab Design and Construction.............................................................................5
Earthwork....................................................................................................................5
General Considerations......................................................................................5
SitePreparation..................................................................................................6
Subgrade Preparation ................... :.................................................................... 7
Fill Materials and Placement...............................................................................7
Shrinkage...........................................................................................................8
Excavation and Trench Construction .......... :....................................................... 8
Additional Design and Construction Considerations.....................................................9
Underground Utility Systems..............................................................................9
Surface Drainage...............................................................................................9
PRELIMINARY GENERAL COMMENTS...........................................................................10
Preliminary Geotechnical Engineering Report
TriTrend, Inc.
Terracon Project No. 20995028
Other design and construction recommendations, based upon preliminary geotechnical
conditions, are presented in the report.
We appreciate being of service to you in the geotechnical engineering phase of this project,
and are prepared to assist you during the 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,
TERRACON
Connie J. Schneider, E.I.T.
Geotechnical Engineer
Copies to:
Reviewed ed by:
illiam J. Attwooll, P_ a,
Office Manager �f °°• <°' a� ��
Addressee (2)
Jili110Vu ��'�..
Big Horn Resources, Inc. — Mr. Gary Kounkel (1)
M
March 25, 1999
TriTrend, Inc.
PO Box 40
Timnath, Colorado 80547
Attn: Mr. Jeff Strauss
Re: Preliminary Geotechnical Engineering Report
160-Acre Ryland Parcel
Southeast corner of East Vine Drive
and Summit View Drive
Fort Collins, Colorado
Terracon Project No. 20995028
Terracon has completed a preliminary geotechnical engineering exploration for the
proposed 160 acre development parcel located at the southeast corner of East Vine Drive
and Summit View Drive in Fort Collins, Colorado. This study was- performed in general
accordance with our proposal number D2099005 dated January 18, 1999.
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 and other earth connected phases of this project are
attached.
The subsurface soils at the site to the depths of 12 to 17 feet consisted of lean clay with
sand, sandy lean clay, and clayey sand. Silty sand and well graded sand was then
encountered to the depths explored. Groundwater was encountered in four of the borings at
approximate depths of 11 to 17 feet below the surface. The remaining boring was dry to the
depth explored. The results of our field exploration and laboratory testing completed for this
study indicate that the soils at the site have low expansive potential and low to moderate
bearing characteristics. I
Based on the subsurface conditions encountered, it is our preliminary recommendation that
lightly loaded structures be supported by conventional -type spread footings and/or grade
beam foundations. Basement and conventional slab -on -grade construction is considered
feasible at the site.
PRELIMINARY GEOTECHNICAL ENGINEERING REPORT
160-ACRE RYLAND PARCEL
NE'/4 OF SECTION 8, TOWNSHIP 7 NORTH, RANGE 68. WEST
SOUTHEAST CORNER OF EAST VINE DRIVE AND SUMMIT VIEW DRIVE
FORT COLLINS, COLORADO
TERRACON PROJECT NO. 20995028 -
March 25, 1999
Prepared for.
TriTrend, Inc.
PO BOX 40
TIMNATH, COLORADO 80547
ATTN: MR. JEFF STRAUSS
Prepared by.
Terracon
301 North Howes Street
Fort Collins, Colorado 80521
Irerracon