HomeMy WebLinkAboutHEARTHFIRE PUD, 1ST FILING - FINAL - 31-95D - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTREPORT 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.
lrerracon
ILABORATORY 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
Thickness
Ratio
materials for use in road and airfield pavements.
Design
Used to develop an estimate of both the rate and amount of
Foundation
Consolidation
both differential and total settlement of a structure.
Design
Used to determine the consolidated drained shear strength of
Bearing Capacity,
Direct
soil or rock.
Foundation Design &
Shear
Slope Stability
Dry
Used to determine the in -place density of natural, inorganic,
Index Property
Density
fine-grained soils.
Soil Behavior
Used to measure the expansive potential of fine-grained soil
Foundation & Slab
Expansion
and to provide a basis for swell potential classification.
Design
Used for the quantitative determination of the distribution of
Soil
Gradation
particle sizes in soil.
Classification
Liquid &
Used as an integral part of engineering classification systems
Plastic Limit,
to characterize the fine-grained fraction of soils, and to
Soil
Plasticity
specify the fine-grained fraction of construction materials.
Classification
Index
to determine the capacity of soil or rock to conduct a
Groundwater
PermeabilityUsed
liquid or gas.
Flow Analysis
Used to determine the degree of acidity or alkalinity of a soil.
Corrosion
p H
Potential
Used to indicate the relative ability of a soil medium to carry
Corrosion
Resistivity
electrical currents.
Potential
Used to evaluate the potential strength of subgrade soil,
Pavement
R-Value
subbase, and base course material, including recycled
Thickness
materials for use in road and airfield pavements.
Design
Soluble
Used to determine the quantitative amount of soluble
Corrosion
Sulphate
sulfates within a soil mass.
Potential
To obtain the approximate compressive strength of soils that
Bearing Capacity
Unconfined
possess sufficient cohesion to permit testing in the
Analysis
Compression
unconfined state.
for
Foundations
Water
Used to determine the quantitative amount of water in a soil
Index Property
Content
mass.
Soil Behavior
l erracon
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. Chert 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)2). May contain noncarbonate impurities such as quartz, chert, clay
minerals, organic matter, gypsum and sulfides. Reacts with hydrochloric acid
(HCQ.
Limestone
A fine-grained carbonate rock consisting of the mineral calcite (CaCo). May
contain noncarbonate impurities such as quartz, chart, 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.
lrerracon
UNIFIED SOIL CLASSIFICATION SYSTEM
Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests"
Coarse -Grained
Soils more than
50% retained on
No. 200 sieve
Fine -Grained Soils
50% or more
passes the
No. 200 sieve
organic soils
Gravels more than
50% of coarse
fraction retained on
No. 4 sieve
Sands 50% or more
of coarse fraction
passes No. 4 sieve
Silts and Clays
Liquid limit less
than 50
Silts and Clays
Liquid limit 50
or more
Clean Gravels Less
Cu > 4 and 1 < Cc <3'
than 5% fines'
— — —
Cu < 4 and/or 1 > Cc > 3`
Gravels with Fines
more than 12% fines
Fines classify as ML or MH
Fines classify as CL or CH
Clean Sands Less
Cu > 6 and 1 < Cc < 3'
then 5% fines'
Cu < 6 and/or 1 > Cc > 3e
Sands with Fines
Fines classify as ML or MH
more than 12% fine So
Fines Classify as CL or CH
inorganic
PI > 7 and plots on or above "A line'
PI < 4 or plots below "A" line
organic
Liquid limit - oven dried
- < 0.75
Liquid limit - not dried
inorganic
PI plots on or above "A" line
PI lots below "A" line
organic
Liquid limit - oven dried
Liquid limit - not dried
matter, dark in color, and organic odor
ABased on the material passing the 3-in.
(D„ 1:
(75-mm) sieve
Off field sample contained cobbles or
.aCu=nbe/p„ Cc -
D.o x Do
boulders, or both, add "with cobbles or
boulders, or both" to group name.
'Gravels with 5 to 12% fines require dual
`If soil contains > 15% sand, add "with
symbols:
sand" to group name.
GW-GM well -graded gravel with silt
'If fines classify as CL-ML, use dual symbol
GW-GC well -graded gravel with clay
GC -GM, or SC-SM.
GP -GM poorly graded gravel with silt
"If fines are organic, add "with organic fines"
GP -GC poorly graded gravel with clay
to group name.
'Sands with 5 to 12% fines require dual
'if soil contains > 15% gravel,, add "with
symbols:
gravel" to group name.
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
eo
Group
GW
GP
GM
GC
SW
SP
SM
SC
CL
ML
OL
CH
MH
< 0.75 OH
Soil Classification
Group Names
Well -graded gravel'
Silty gravel,G,H
Clayey gravel`•0,"
Well -graded sand'
Poorly graded sand'
Silty sand',"-'
Clayey sand'"'
SiltK.L.M
Organic ClayK.L.M.
Organic silt K.L,M.o
Fat claysL•M
Elastic Silts•L•M
slitK,L,M.0
PT Peat
'If soil contains 15 to 29% plus No. 200, add
"with sand" or "with gravel", whichever is
predominant.
Llf soil contains > 30% plus No. 200
predominantly sand, add "sandy" to group
name.
MY soil contains > 30% plus No. 200,
predominantly gravel, add "gravelly" to group
name.
"PI > 4 and plots on or above "A" line.
°PI < 4 or plots below "A" line.
'PI plots on or above "A" line.
°PI plots below "A" line.
ro, 11.. .1n. of nn. of
"ne n".- ."thee oaen.n .fu",,.- f
La"mron of •: - 1-4
w-.f.a-21.1
m t then - 0,73 LL - 201
[c.mmn of 'u' - i;n. —
v..Uwf m LL - fe to
then n - os (LL
OQ-
MH 0R
OH
I
ML oR OL
I
CL-ML
_-
I
0
o to m 20 50 +C e7 so 70 eo so foo ne
LIgCID LIMIT (LL)
�'eEn rraC 0 n
DRILLING AND EXPLORATION
TILLING & SAMPLING SYMBOLS:
oS : Split Spoon - 1-3/e" 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. FT : Fish Tail Bit
PA : Power Auger RB : Rock Bit
HA : Hand Auger BS : Bulk Sample
DB : Diamond Bit
Pressure Meter
AS : Auger Sample D: C
HS : Hollow Stem Auger W :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: WS ; While Sampling
WL :Water Level
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.
50% their dry
Slight
Slight decomposition of parent material on
Coarse Grained Soils have more than of
retained on a #200 sieve; they are described as:
joints. May be color change.
weight
oulders, cobbles, gravel or sand. Fine Grained Soils have
their dry weight retained on a #200 sieve;
Moderate
Some decomposition and color change
>s than 50% of
rhey are described as: clays, if they are plastic, and silts if
throughout.
they are slightly plastic or non -plastic. Major constituents
be added as modifiers and minor constituents may be
High
Rock highly decomposed, may be extremely
may
added according to the relative proportions based on grain
broken.
size. In addition to gradation, coarse grained soils are
basis of their relative in -place density and
HARDNESS AND DEGREE OF CEMENTATION:
defined on the
fine grained soils on the basis of their consistency.
Lean with sand, trace gravel, stiff (CL); silty
Limestone and Dolomite:
Hard Difficult to scratch with knife.
Example: clay
sand, trace gravel, medium dense ISM).
Moderately
Can be scratched easily with knife,
CONSISTENCY OF FINE-GRAINED SOILS
Hard
Cannot be scratched with fingernail.
Soft
Can be scratched with fingernail.
Unconfined Compressive
Strength, Qu, psf Consistency
Shale Siltstone and Claystone:
500 Very Soft
Hard
Can be scratched easily with knife, cannot
<
Soft
be scratched with fingernail.
500 - 1,000
1,001 - 2,000 Medium
Stiff
Moderately
Can be scratched with fingernail.
2,001 - 4,000
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
Very Loose
Sandstone and
Conglomerate:
0-3
Loose
Well
Capable of scratching a knife blade.
4-9
10-29 Medium Dense
Cemented
30-49 Dense
Very Dense
Cemented
Can be scratched with knife.
50-80
80 + Extremely Dense
Poorly
Can be broken apart easily with fingers.
Cemented
error-®n_
SUMMARY OF TEST RESULTS
PROJECT NO. 20955191
Dry
Compressive
Swell Soluble
pH Liquid
Plasticity
Group Classification
O
OHMResist`CM) vity Penetration
n.
Boring Depth
Moisture
%
Density
Strength
Pressure Sul fates
Limit
Index
Ind
Index
USCS
No. Ft.
(PCF)
(PSF)
(PSG
17/12
1 .5-1.5
16
32
18
8 A-6(8); CL
3-4
8
98
4860
1630
17/12
4-5
9
15/12
7-8
9
20/12
14-15
11
15/12
2 .5-1.5
17
16/12
3-4
10
7-8
16
112
4300
4/12
8-9
19
25/12
14-15
22
15/12
3 .5-1.5
9
3-4
10
115
13,580
1000
15/12
4-5
10
8/12
S-9
13
5/12
14-15
25
22/12
4 .5-1.5
17
3-4
9
110
7080
1015
16/12
4-5
9
13/12
7-8
6
8/12
14-15
23
0
I_F_GEND
35—Fort Collins lotuu, I to rI perecul elopes. This
ncarl,y level soil is on terraces and falls. This soil has n
profile similar to the one described as representative
of the series, hilt the combined Lhickness of the surface
layer and subsoil is about 22 inches.
Included with this soil in nnlpping are a fete small
are:ls of soils tln:lt arc more sloping or less sloping. Also
included are some small areas of Stoneham and Kim
soils and a fe.w small areas of soils that have a gravelly
layer below a depLh of 10 inches.
Runoff is slow, ;old the hazards of wind and water
erosion :uc slight; to moderate.
If irrigated, this soil is well sidled to corn, sugar
heels, alfall'a, baricy, and dry heals. Under dryland
ill:lnagemenL it is suited to wheat and barley. It is also
well suited to pasture and native grasses. Capability
units Ile-1, irrilMicII, anrd lvc-,I, dryland; Loamy
Plains range site; windbreak suitability group I.
5.I—Mini loom, ;S 10 5 pm'eont slopes. This frelntly
sloping soil is on uplands aril falls. This soil has a
profile sinlflar to the one described as representative
of the series, but the surface layer is about 10 inches
thick.
Included with this soil in napping are small areas
of soils that arc more sloping or less sloping and small
:Ll'e.:ts of soils Hutt Bove a surface layer of cl;ly loan.
A water table is within the root zone daring the grow-
ilig season in a few small areas. Also included are a
fcty small areas of Foil, Collins, Stonclutm, and Theda-
lund soils.
Runoff is medium, and the hazard of erosion is mod-
eraLe.
if irrigated, this soil is suited to barley, alfalfa, and
wheat and, to a lesser ezlenL, corn and beans. Under
dryland nlanagcnicnt it is suited to pasture and native
grasses. Capability nails Ilse-2, irrigated, and 1Ve-3;
lhyl:urtl, ],nanny Plains range site; fvindbrealc suit-
ability group 1.
103-51onclnuu loans, 5 to 9 /erecut elopes. This
strongly sloping soil is on uplan�s and high terraces
:urll benches, nn;lntly ne;u' tltc edge. This soil has a pro-
lil , sinnil:u' to the one described as rcprescnLative of
the series, but the combined surface layer and subsoil
is about 10 to 12 inches thick.
Included with Lhis soil in mapping are small gravel.
spots and small areas of soils that are redder and have
a surface layer of sandy loam. Also included are small
areas of Fort Collins, Kim, and Larilllcl' soils.
Rtmofl' is rapid, and the hazard of erosion is severe.
If irrigAud, Lhis soil is well suited to llasLurc and,
to a lesser exlanL, whcaL, barley, and alfalfa. Under
dryland management it is suited to. pasture or native.
grasses. Capability units IVe-1, irrigated, and VIe-1,
dryland; Loamy Plains range site; windbreak snit
ability, group 1.
1 re itt ff 9 ca& c o
CONSULTANTS WESTERN. INC.
EMPIRE DIVISION
LOG OF BORING No. 6
Page 1 of 1
CLIENT
ARCITITECT / ENGINEER
Merrick & Company
Merrick & Company
SITE Douglas Road & County Road 13
PROJECT
Larimer County, Colorado
Hoffman Subdivision Filing No. 1
SAMPLES
TESTS
0
—1
LL
CO
z
r
W
W
H
U)
Z 2
W
H
DESCRIPTION
>-
m
z
W
z
HF-
W
=
2
W
>
I (n
H
O
ZZ
JfA
(L
2
F-
a.
!n
U
CO
E
W
a.
O
U
3.
t- O
UI
H
>- LL_
OW
U ceLL.
JU)
W W LL.
01-1
Approx. Surface Elev.: 5095.0 ft.
W
O
W
o
O
z
>-
W
m
a_J
(nm
O
E
WU
OIL
ZF-U7
ovJa
3wUI
cno-a.
" " "
0.5 6" TOPSOIL 5094.5
I
SS
12"
16
20
SANDY LEAN CLAY
Brown, moist, medium to stiff
CL
2
SS
12"
6
17
5
6.0 5089.0
WEATHERED CLAYSTONE/
7.0 SANDSTONE 5088.0
Brown, moist
205
—
3
SS
8"
50/.7
17
Moderately hard, cemented
—
s
CT AYSTONE/SANDSTONE
—_
_
Brown, moist, hard, well cemented
—
14.5 5080.5
BOTTOM OF BORING
10
4
SS
5"
50/A
15
THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES
BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL.
WATER LEVEL OBSERVATIONS
1➢ .� '
11 ff��
BORING STARTED 7.6-87
WL
Q None W.D.
Y 8.5' A•B
BORING COMPLETED 7-6_87
WL
RIG CME-55
FOREMAN LRS
1VL
APPROVED NRS
JOB,N 20955191
LOG Or
BORING No. 5
Page
1 of 1
CLIENT
ARCHITECT / ENGINEER
Merrick & Company
Merrick & Company
SITE
Douglas Road & County Road 13
PROJECT
Larimer County, Colorado
Hoffman Subdivision Filing No. 1
SAMPLES
TESTS
F-
N
>-
H
O
U
J
O
O
J
LLz
W
W
(n
Z=
W
U
DESCRIPTION
r
O
0:
Z \
tr
z
"I—
0:
H
=
2
W
�
i Cn
F=-
O
ZZ
JN
D-
H
(n
CO
W
O
3
(n
O W
J V)
(L
U
E
(L
U
Ho
H
>- LL
U W LL
W W LL
Approx. Surface Elev.: 5083.0 ft.
W
n
W
Z:)
D
z
>-
I-
W
W
dJ
N (n
O
E
KU
o 0-
ZF-(n
(n o_
30:(n
(n n. a
A^A
0 5 6" TOPSOIL 5082.5
1
1
1 ISSI
12"
20 1
11
1
WEATHERED SANDSTONE
Tan, moist, poorly cemented
2.0 5081.0
SANDSTONE
Tan, moist, well cemented
14.3 5068.7
BOTTOM OF BORING
5
1101
3 SS 4" 50/.3 I 14
I 1 4 1 SS 1 12" 150/.3 1 141 1 1
ITHE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES
BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL.
WATER LEVEL OBSERVATIONS
WL QNone W.D. = 6.0' A.B. � �rr
WL
WL
BORING STARTED 10-31-95
BORING COMPLETED 10-31-95
RIG CME-55 FOREMAN DML
APPROVED NRS JOB H 2O955191
LOG OF BORING No. 4 Page 1 of 1
ARCHITECT / ENGINEER
CLIENT Merrick & Company
Merrick & Company
SITE Douglas Road & County Road 13 PROJECT
Larimer County, Colorado Hoffman Subdivision FilingNo. 1
TESTS
Lo
O
J
U I DESCRIPTION
H
2
o-
00 Approx. Surface Elev.: 5112.E rt.
0.5 6" TOPSOIL
15.0
CANDY LEAN CLAY
Brown, dry to moist
Stiff to very stiff
SAMPLES
Jo
1—
O
v
}
W
Z
Of
Z
H I2-
D:
In
K
W
W
�
1 N
O
F-
W
O
LL (D
Z Z
O
J to
=
1-
fn
tD
W
O
U
3
F- O
(n
H
>- U_.
Ow
U <L
J!n
W W 11
4.
U
E
0-
O
O
Z
F-
O!
tom
r_
O0-
MMd
M0.0-
1
SS
12"
22
17
S111.5
BOTT01v1 OF BORING
7-
C L
2
ST
12"
1
9
110
7080
1
3
1 SS 1
12"1
16 1
9
R
10
15
THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES
BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL.
WATER LEVEL OBSERVATIONS'Irt®�
WL Q None W.D. Y 1�1.1' A.B. er■ WL
WL
4Ts-S1 12"1 13 1 6
5 1 SS 1 12" 1 8 1 23
1015
BORING STARTED 7-6-87
BORING COMPLETED 7-6-87
RIG. CNIE-55 FOREMAN LRS
APPROVED FIRS JOB k 20955191
LOG OF
BORING No. 3
Page 1 of 1
ARCHITECT
/ ENGINEER
CLIENT
Merrick & Company
Merrick & Company
SITE
DoT)glas Road & County Road 13
PROJECT
Larimer County, Colorado
Hoffman Subdivision Filing No.
1
SAMPLES
TESTS
cD
0
1-
1—
o
0
J
LL
co
�
z
H�
c�
DESCRIPTION
r
N
M
Z\
WO
Zz
H
=
W
>
I U)
F
JN
m
W
O
3
N
O W
J to
O_
O-
U
r
O_
U
F O
H
>- LL
U W LL
W W LL
W
to
O
}
W
O-J
O
Q�U.
ZF-Ln
:lx(n
Approx. Surface ] lev.: 5101.5 ft.
0
Z)
Z
F-
O_
mm
�
O0-
too-
N(La-
".0.5
6" TOPSOIL 5101.0
1
SS
12"
15
9
15.0
SANDY LEAN CLAY
Brown, dry to moist, stiff to hard
BOTTOM OF BORING
i
W
10
15—
CL
2
ST
12"
10
115
13580
1000
10
3
SS
12"
15
4 1 SS 1 12"1 8 1 13
5 1 SS 1 12" 1 5 1 25
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 10-31-95
WL 4 None W•D• None A. BORING COMPLETED 10-31-95
WL lVerrac
RIG C�-55 FOREIvLAN DNIL
WL APPROVED NRS JOB N 20955191
LOG OF BORING No. 2 Page 1 of 1
ARCHITECT / ENGINEER
CLIENT
Merrick & Company Merrick & Company
SITE Douglas Road & County Road 13 PROJECT
Larimer Count , Colorado Hoffman Subdivision Filing No. 1
.-.
SAMPLES
TESTS
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Brown, moist, stiff to very stiff
5
2 1 SS 1 12" 1 16 1 10
10-
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4983.0
WEATHERED SANDSTONE
Tan, moist, poorly cemented
5 1 SS 1 12" 1 25 1 22
15.0 4981.0 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 BORING STARTED 7-6-87
WL Q 12.0 WD• Y 9.7' A•B 'rCA
BORING COMPLETED 7-6-87
WL er� Lit RIG CIVIE-55 FOREMAN LRS
WVWater checked 10 days A.B. ® APPROVED j�(IjS JOB H 2O955191
LOG OF BORING No. 1
Page 1 of 1
CLIENT
I!!
ITECT / ENGINEER
Merrick & Company
Merrick & Company
SITE Douglas Road & County Road 13
PROJECT
Larimer County, Colorado
Hoffman Subdivision Filing No. 1
SAMPLES
TESTS
I-
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DESCRIPTION
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Approx. Surface Elev.: 5120.0 ft.
O
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"
0.5 6" TOPSOIL 5119.5
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PSF
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8
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20
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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
I��damftalmn
130RING STARTED 7-6-87
WL
g None W.D.
IT None A.B.
BORING COMPLETED 7-6-87
WL
RIG CME-55
FOREMAN LRS
WL
Water checked 10 days A.B.
APPROVED NRS
JOB H 20955191
v .
10
103
•
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. :
FIGURE 1: SITE PLAN
DOUGLAS ROAD & COUNTY ROAD Q
TORT COLLINS COLORADO
ELL PROJECT No. 20955
� r army
CONSULTANTS WESTERN, INC.
EMPIRE DIVISION
pn�k,L.pS `2oP,�
FIGURE 1: SITE PLAN
DOUGLAS ROAD & COUNTY ROAD 13
LARIMER COUNTY, COLORADO
ELI. PROJECT No. 20955191
SCALE 1" = 400'
1 renrarcon
CONSULTANTS WESTERN. INC.
EMPIRE DIVISION
rl\
FIGURE 1: SITE PLAN
DOUGLAS ROAD & COUNTY ROAD 13
LARIMER COUNTY COLORADO
ELI. PROJECT No. 20955191
SCALE 1" = 400
I rerrac
CONSUL?A147S WESTERN, INC.
EMPIRE O1%lSION
Preliminary Geotechnical Engineering Exploration Terracon
Merrick & Company
TCW Project No. 20955191
Up = 15to25xD
Where: UP = the uplift force in kips, and
D = the pier diameter in feet
Basement Construction: Groundwater was encountered on the majority of the site. at
depths of 6 to 14 feet below existing grade. •Full -depth basement construction is
considered feasible on the site provided that basement subgrade is a minimum of 3 feet
above existing groundwater. Finished basement slabs should be placed a minimum of 3 feet
above the bedrock stratum. A complete dewatering system should be provided around the
basement area.
Perched groundwater may occur at times since the subsurface soils are relatively
impermeable and tend to trap water. Completion of site development, including installation
of landscaping and irrigation systems, will likely lead to perched groundwater development.
To reduce the potential for groundwater to enter the basement of the structure, installation
of a dewatering system is recommended. The dewatering system should, at a minimum,
include an underslab gravel drainage layer sloped to a perimeter drainage system.
Floor Slab Design and Construction: The variability of the existing soils at approximate slab
subgrade elevation could result in differential movement of floor slab -on -grade should
expansive soils become elevated in moisture content. Use of structural floor systems,
structurally supported independent of the subgrade soils, is a positive means of eliminating
the potentially detrimental effects of floor movement.
• Compliance: Recommendations for 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.
PRELIMINARY 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
f:01
Preliminary Geotechnical Engineering Exploration
Merrick & Company
TCW Project No. 20955191
• Site Clearing:
Terracon
1 . 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.
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. 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.
4. All exposed areas which will receive fill, once properly cleared and benched
where necessary, should be scarified to a minimum depth of 6 inches,
conditioned to near optimum moisture content, and compacted.
a Utility and Site Grading:
1. It is anticipated that excavations for the proposed construction can be
accomplished with conventional earthmoving equipment.
2. Excavations penetrating the well -cemented sandstone bedrock may require
the use of specialized heavy-duty equipment, together with drilling and
blasting, ripping or jack -hammering to facilitate rock break-up and removal.
3. Depending upon depth of excavation and seasonal conditions, groundwater
may be encountered in excavations on the site. Groundwater seepage should
be anticipated for excavations approaching the level of the bedrock. Pumping
from sumps may be utilized to control water within excavations. Well points
may be required for significant groundwater flow, or where excavations
penetrate groundwater to a significant depth.
[:
Preliminary Geotechnical Engineering Exploration
Merrick & Company
TCW Project No. 20955191
Terracon
Field and Laboratory Test Results: Field and laboratory test results indicate the clay soils
are medium to very stiff in consistency and exhibit moderate to high bearing characteristics
and moderate to high swell potential. The bedrock is moderately hard to hard and cemented
to well cemented and exhibits very high bearing characteristics and low swell potential.
Groundwater Conditions: Groundwater was encountered in Boring 2 at the time of drilling
and when checked 1 to 10 days after drilling, groundwater was encountered in Borings 2
through 6 at approximate depths of 6 to 14 feet. Boring 1 remained dry. These
observations represent groundwater conditions at the time of the readings, 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, seasonal and weather conditions.
Fluctuations in groundwater levels can best be determined by implementation of a
groundwater monitoring plan. Such a plan would include installation of groundwater
monitoring wells, and periodic measurement of groundwater levels over a sufficient period
of time.
The possibility of groundwater fluctuations should be considered when developing design
and construction plans for the project.
PRELIMINARY CONCLUSIONS AND RECOMMENDATIONS
Site Development Considerations: The site appears suitable for the proposed construction.
Although fill or underground facilities, such as septic tanks, cesspools, basements and
utilities, were not observed during site reconnaissance, such features might be encountered
during construction.
5
Preliminary Geotechnical Engineering Exploration
Merrick & Company
TCW Project No. 20955191
Terracon
The regional dip of the Pierre shale in this area is slight and in an easterly direction. Seismic
activity in the area is anticipated to be low; therefore, from a structural standpoint, the
property should be relatively stable. It is anticipated that the weathered bedrock and the
majority of the firm bedrock may be excavated by conventional heavy-duty construction
equipment equivalent to a D-8 tractor and ripper or a large track -mounted backhoe.
However, the sandstone becomes dense at lower depths. This dense sandstone at depth
may require the use of special heavy-duty excavation equipment or possibly blasting for
excavation. Due to the relatively flat to gently -rolling nature of the site, geologic hazards
due to mass movement caused by gravity, such as landslides, mudflows, rockfalls, etc., are
not anticipated. With proper site grading around structures and proper drainage for streets
and drive areas, erosional problems at the site should be minimal. It is recommended that
construction not be placed within the wet areas in the central portion of the site without
proper draining and filling.
The site is underlain by the Cretaceous Pierre Formation. The Pierre shale is not known to
contain economic deposits of coal, limestone, or quarry rock. Sand and gravel was not
encountered at the site, and economic deposits of these materials are not anticipated.
Background levels of radioactivity are anticipated to be low in this area. However, the
possibility does exist that abnormal;y high radiation rates may exist on the property. A
detailed study of radon gas or radiation hazards at the site is beyond the scope of this
report. It is suggested that a more detailed study be made prior to construction to more
accurately determine if radiation hazards exist at the site.
Soil and Bedrock Conditions: As presented on the Logs of Boring, the subsurface soils were
encountered in order of increasing depths.
® Silty Topsoil: The area tested is overlain by a 6-inch layer of silty topsoil. The
topsoil has been penetrated by root growth and organic matter.
O Sandy Lean Clay: This stratum underlies the topsoil and extends to the bedrock
below and/or the depths explored. The sandy lean clay is plastic, dry to wet and
medium to very hard.
o Sandstone-Siltstone Bedrock: The bedrock was encountered in Borings 2, 5 and 6
at depths of '/2 to 13 feet and extends to greater depths. The upper 1 to 1'/z feet
of the bedrock is highly weathered; however, the underlying sandstone interbedded
with claystone is well -cemented and hard.
4
Preliminary Geotechnical Engineering Exploration Terracon
Merrick & Company
TCW Project No. 20955191
• Water content a Expansion
e Dry density • Atterberg limits
The significance and purpose of each laboratory test is described in Appendix C. Laboratory
test results are presented in Appendix B, and were used for the geotechnical engineering
analyses, and the development of foundation and earthwork recommendations. All
laboratory tests were performed in general accordance with the applicable ASTM, local or
other accepted standards.
SITE CONDITIONS
The site surrounds an existing lake and wetlands areas. The area is vegetated with native
grass and Russian olive and cottonwood trees and brush. Cattails were noted growing in
the wetlands area. Fences are located throughout the property along with several oil wells.
The site is bordered on all'sides by fenced pasture land. Drainage, in general, is from the
north, south, east and west toward the lake and wetlands in the center of the project. The
property is bordered on the west by Larimer County Road.13, on the southwest by Richards
Lake, and on the north and east by open pasture.
SUBSURFACE CONDITIONS
Geology: The proposed area is located within the Colorado Piedmont section of the Great
Plains physiographic province. The Colorado Piedmont, 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. The Pierre shale at the site consists of sandstone and claystone. Bedrock
was encountered in Borings 2, 5, and 6 at depths of '/z to 13 feet, and it is anticipated it
underlies the remainder of the site at depths of 20 to 25 feet. The bedrock is overlain by
residual and alluvial clays of Pleistocene and/or Recent Age. A Geologic Map, Soil Map and
legend are included in Appendix A.
3
Preliminary Geotechnical Engineering Exploration Terracon
Merrick & Company
TCW Project No. 20955191
SITE EXPLORATION
The scope of the services performed for this project included site reconnaissance by a
geotechnical engineer and an engineering geologist, a subsurface exploration program,
laboratory testing and engineering analysis.
Field Exploration: A total of 6 test borings were drilled on July 6, 1987 and October 31,
1995 to depths of 15 feet at the locations shown on the Site Plan, Figure 1. The borings
were drilled within the area of proposed buildings. All borings were advanced with a truck -
mounted drilling rig, utilizing 4-inch diameter solid stem auger.
The borings were located in the field by pacing from property lines and/or existing site
features. Elevations were taken at each boring location from a topographic map prepared
by Merrick & Company. 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 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 driving split -spoon samplers.
Penetration resistance measurements were obtained by driving the split -spoon into the
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.
Groundwater measurements were made in each boring at the time of site exploration, and
1 to 10 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. 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, 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:
2
PRELIMINARY GEOTECHNICAL ENGINEERING REPORT Terracon
THE POND AT HEARTHFIRE
DOUGLAS ROAD AND COUNTY ROAD 13
FORT COLLINS, COLORADO
TCW Project No. 20955191
April 22, 1996
INTRODUCTION
This report contains the results of our preliminary geotechnical engineering exploration for
the proposed first filing of The Pond at Hearthfire located at the southeast corner of Larimer
County Road 13 and Douglas Road, northeast of Fort Collins, Colorado. The site is located
in the West 1 /2 of Section 30, Township 8 North, Range 68 West of the 6th Principal
Meridian.
The purpose of these services is to provide preliminary geotechnical engineering information
relative to:
• subsurface soil and bedrock conditions
e groundwater conditions
• earthwork
0 preliminary foundation systems
• basement construction
O preliminary floor slab design and construction
.• utilities
The conclusions and recommendations contained in this report are based upon the results
of limited field and laboratory testing, engineering analyses, and experience with similar soil
conditions and structures and our understanding of the proposed project. Prior to final
design, additional studies will be required.
PROPOSED CONSTRUCTION
The site will be developed as a residential subdivision with single-family and multifamily
housing. Residential streets will be constructed throughout the project area. Grading plans
were not available at the time of preparation of this report, and it is anticipated that some
cut and fill will be required.
Preliminary Geotechnical Engineering Exploration
Merrick & Company
TCW Project No. 20955191
TABLE OF CONTENTS (Cont'd)
Terracon
APPENDIX A
Figure Nos
SitePlan .................................................. 1
Geologic Map ............................................. 1
SoilsMap ................................................ 1
Logs of Borings ..................................... Al thru A6
Legend 7
APPENDIX B
Summary of Test Results ............ . ........................ B1
APPENDIX C: GENERAL NOTES
Drilling & Exploration ......................................... U i
Unified Soil Classification .................................... C2
Bedrock Classification, Sedimentary Bedrock ....................... C3
Laboratory Testing, Significance and Purpose ...................... C4
Report Terminology ........................................ C5
Preliminary Geotechnical Engineering Exploration Terracon
Merrick & Company
TCW Project No. 20955191
TABLE OF CONTENTS
Page No.
Letter of Transmittal ............................................... ii
INTRODUCTION................................................ 1
PROPOSED CONSTRUCTION ....................................... 1
2
SITE EXPLORATION .............................................
Field Exploration ..........................................
2
Laboratory Testing .........................................
2
SITE CONDITIONS .............................................. 3
CIIRCI IRFArF rnKIDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . 3
3
Geology................................................
Soil and Bedrock Conditions ..................................
4
Field and Laboratory Test Results
............................... 5
Groundwater Conditions .....................................
5
PRELIMINARY CONCLUSIONS AND RECOMMENDATIONS .................. 5
Site Development Considerations ............................... 5
Site Clearing ................ . ....................... 6
Utility and Site Grading ...... ......................... 6
Fill Materials ........................................ 7
Foundation Systems ........................................ 7
Basement Construction ...................................... 8
Floor Slab Design and Construction ............................. 8
Compliance ......................................... 8
PRELIMINARY GENERAL COMMENTS ................................ 8
Preliminary Geotechnical Engineering Exploration Terracon
Merrick & Company
TCW Project No. 20955191
Preliminary earthwork considerations are presented in the report.
We appreciated being of service during the preliminary deotechnical engineering phase of
this project, and are prepared to assist during the final geotechnical phase 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 CONSULTANTS WESTERN,
Empire Division
Pr,
Neil R. Sher ocl
Senior Engineering Geologist
Reviewed by:
n
William J. Attwooll; P.E. F
Assistant OfficeManagel G•5r `44
NRS/WJA/cic
r v,e i
Copies to: Addressee (2)
Jim Sell Design (1)
2575
A.IPG
Irerracon
CONSULTANTS WESTERN, INC.
EMPIRE DIVISION
P.O. Box 503 • 301 N. Howes
Fort Collins, Colorado 80522
(970)484-0359 Fax (970) 484-0454
Larry G. O'Dell, P.E.
Neil R. Sherrod, C.P.G.
April 22, 1996
Merrick & Company
2450 South Peoria Street
Aurora, Colorado 80014
Attn: Mr. Glen Tulk
Re: Preliminary Geotechnical Engineering Report, The Pond at Hearthfire
Douglas Road and County Road 13, Fort Collins, Colorado
TCW Project No. 20955191
Terracon Consultants Western, Inc., Empire Division, has completed a preliminary
geotechnical engineering exploration for the proposed Filing 1 of The Pond at Hearthfire to
be located on Larimer County Road 13 south of Douglas Road, northeast of Richards Lake
and northeast of Fort Collins, Colorado.
The results of our engineering study, including the boring location diagram, laboratory test
results, test boring records, and the preliminary geotechnical recommendations needed to
aid in the preliminary design and construction of foundations and other earth connected
phases of this project are attached.
The subsurface soils at the site consist of sandy lean clays underlain by sandstone-
claystone bedrock. The information obtained by the results of field exploration and
laboratory testing completed for this study indicate the soils at the site exhibit moderate to
high swell potential and moderate to high bearing characteristics. The bedrock at the site
exhibits high bearing characteristics and low swell potential. The soils at anticipated
foundation bearing depths exhibit medium to stiff consistency, and the bedrock varies from
medium hard to very hard to cemented and well cemented.
Based on the preliminary geotechnical engineering analyses, subsurface exploration and
laboratory test results, we recommend the proposed residences be supported on a
conventional -type spread footing and grade beam and/or straight shaft pier foundation
systems. Slab -on -grade may be utilized for the interior floor system provided that care is
taken in the placement and compaction of the subgrade soil. If no movement can be
tolerated, a structural floor system should be specified.
Offices of The Terracon Companies, Inc. Geotechnical, Environmental and Materials Engineers
Arizona is Arkansas ■ Colorado ■ Idaho ■ Illinois ■ Iowa ■ Kansas i Minnesota
Missouri Y Montana ■ Nebraska o Nevada ■ Oklahoma ■ Texas ■ Utah o Wyoming
QUALITY ENGINEERING SINCE 1965
PRELIMINARY GEOTECHNICAL ENGINEERING REPORT
THE POND AT HEARTHFIRE
DOUGLAS ROAD AND COUNTY ROAD 13
FORT COLLINS, COLORADO
TCW PROJECT NO. 20955191
April 22, 1996
Prepared for.
MERRICK & COMPANY
2450 SOUTH PEORIA STREET
AURORA, COLORADO 80014
ATTN: MR. GLEN TULK
Prepared by.
Terracon Consultants Western, Inc.
Empire Division
301 North Howes Street
Fort Collins, Colorado 80521
Empire Laboratories, Inc.
A Division of The Terracon Companies, Inc. I .
Preliminary Geotechnical Engineering Exploration Terracon
_. Merrick & Company
TCW Project No. 20955191
4. On -site clay soils 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.
e Fill Materials:
1. On -site clay soils are suitable for use beneath slabs or as backfill.
2. On -site bedrock materials are not recommended for use beneath structural
ares of the site, or as backfill. Should bedrock materials be used for general
site grading, placement in fills at non-structural locations on the site is
recommended.
Foundation Systems: Due to the presence of moderate of high swelling soils on the site,
spread footing and/or grade beam foundations bearing upon undisturbed subsoils and/or
engineered fill are recommended for support for the proposed structures. Consideration
should be given to using. drilled pier foundations for structures founded partly on the
bedrock stratum and partly in the clay soils. Additional testing should be done prior to final
design. Based on preliminary test results, footing and/or grade beams founded on the
undisturbed soil should be designed for a maximum allowable bearing capacity of between
2,000 to 4,500 pounds per square foot (dead load plus 1/2 live load). To counteract
swelling pressures which will develop if the subsoils be wetted, all footings should be
designed for a minimum dead load pressure of 500 to 1,500 per square foot.
Where drilled pier foundation systems are used, the piers would have minimum 12 to 15
foot lengths and extend a minimum of 5 feet into the bedrock stratum. Based on
preliminary test results, the piers should be designed for a maximum end bearing pressure
of between 15,000 to 30,000 psf and skin friction of 1,500 to 3,000 psf. For preliminary
design purposes, the uplift force on each pier can be determined on the basis of the
following equation.
SUMMARY OF TEST RESULTS
PROJECT NO. 20955191
Boring
No.
Depth
Ft.
Moisture
%
Dry
Density
(PCF)
Compressive
Strength
(PSF)
Swell
Pressure
(PSF)
Soluble
Sulfates
%
pH
Liquid
Limit
%
Plasticity
Index
%
Group
Index
Classification
AASHTO
USCS
Resistivity
(OHM -CM)
Penetration
Blow/In.
5
.5-1.5
11
20112
4-4.5
11
80
50/6
8-8.3
14
50/4
14-14.3
14
50/4
6
.5-1.5
20
16/12
3-4
17
6/12
7-7.6
17
205
50/8
14-14.5
15
50/5
Preliminary Geotechnical Engineering Exploration
Merrick & Company
TCW Project No. 20955191
Terracon
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.
9
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.
Alluvium
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.
Backfill
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.
Differential
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
lateral to be equivalent to that produced by the
against a support presumed
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
Materials deposited through the action of man prior to exploration of the site.
man-made fill)
Existing Grade
The ground surface at the time of field exploration.
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