HomeMy WebLinkAboutHARMONY SCHOOL SHOPS PUD - PRELIMINARY - 42-89D - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTPRELIMINARY GEOTECHNICAL ENGINEERING REPORT
HARMONY SCHOOL SHOPS
TIMBERLINE ROAD AND HARMONY ROAD
FORT COLLINS, COLORADO
TERRACON PROJECT NO. 20955160
September 22, 1995
Prepared for.
GT LAND, INC.
3555 STANFORD ROAD
FORT COLLINS, CO 80525
ATTN: MR. STAN WHITTAKER
lrerrocon
September 22, 1995
GT Land, Inc.
3555 Stanford Road
Fort Collins, CO 80525
Attn: Mr. Stan Whittaker
Re: Preliminary Geotechnical Engineering Report
Timberline Road and Harmony Road
Fort Collins, Colorado
Terracon Project No. 20955160
Irerracon
CONSULTANTS WESTERN, INC.
P.O. Box 503 •301 N. Howes
Fort Collins, Colorado 80522
(970) 484-0359 Fax (970) 484-0454
Chester C. Smith, P.E.
Larry G. O'Dell, P.E.
Neil R. Sherrod, C.P.G.
Terracon Consultants Western, Inc. (Terracon) has completed a preliminary geotechnical
engineering study for the proposed project to be located at the northeast corner of
Timberline Road and Harmony Road in southeast Fort Collins, Colorado. This study was
performed in general accordance with our proposal number D2095248 dated September 19,
1995.
The results of our preliminary engineering study, including the boring location diagram,
laboratory test results, test boring records, and preliminary geotechnical recommendations
needed to aid in the design and construction of foundations and other earth connected
phases of this project are attached. The accompanying geotechnical report presents our
preliminary findings and recommendations concerning the design and construction of
foundations and general site development. Further details are provided in this report.
We appreciate the opportunity to be of service to you on this phase of your project. If you
have any questions concerning this report, or if we may be of further service to you, please
do not hesitate to contact us.
Sincerely,
TERRACON CONSULTANTS WESTERN, INC.
Empire Division
Prepared by:
.... 7aii11/1/1�//,
,p; ;�I;�Ar��r
Reviewed y:
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isa R. Schoenfeld, P.E.
° _ =
William J. Attwooll, P.E.
Geotechnical Engineer
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Assistant Office Manager
LRS/WJA/dmf
Copies to: Addressee (3)
Offices of The Terracon Companies, Inc. Geotechnical, Environmental and Materials Engineers
Arizona ■ Arkansas ■ Colorado ■ Idaho ■ Illinois ■ Iowa ■ Kansas ■ Minnesota
Missouri ■ Montana ■ Nebraska ■ Nevada ■ Oklahoma ■ Texas ■ Utah ■ Wyoming
QUALITY ENGINEERING SINCE 1965
Geotechnical Engineering Exploration
GT Land, Inc.
Terracon Project No. 20955160
TABLE OF CONTENTS
Page No.
Letter of Transmittal ............................................... i
INTRODUCTION................................................ 1
PROPOSED CONSTRUCTION ...................................... 1
SITE EXPLORATION ............................................. 2
Field Exploration .......................................... 2
Laboratory Testing ......................................... 2
SITE CONDITIONS .............................................. 3
SUBSURFACE CONDITIONS ....................................... 3
Soil Conditions ............................................ 3
Field and Laboratory Test Results ............................... 4
Groundwater Conditions ..................................... 4
PRELIMINARY CONCLUSIONS AND RECOMMENDATIONS .................. 4
Site Development Considerations ............................... 4
Earthwork............................................... 4
Site Clearing ........................................ 4
Foundation Systems ........................................ 5
PRELIMINARY GENERAL COMMENTS ................................ 5
APPENDIX A
Site Plan .......................................... Figure No. 1
Logs of Borings ..................................... Al thru A4
APPENDIX B: GENERAL NOTES
Drilling & Exploration ....................................... C1
Unified Soil Classification .................................... C2
Laboratory Testing, Significance and Purpose ...................... C3
Report Terminology ........................................ C4
PRELIMINARY GEOTECHNICAL ENGINEERING REPORT
HARMONY SCHOOL SHOPS
TIMBERLINE ROAD AND HARMONY ROAD
FORT COLLINS, COLORADO
Terracon Project No. 20955160
September 22, 1995
INTRODUCTION
Terracon
This report contains the results of our preliminary geotechnical engineering exploration for
the proposed project to be located at the northeast corner of Timberline Road and Harmony
Road in southeast Fort Collins, Colorado. The site is located in the SW %< of Section 32,
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 conditions
• groundwater conditions
• earthwork
• foundation design and construction
The conclusions and recommendations contained in this report are based upon the results
of limited field and laboratory testing, engineering analyses, our 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
Based on information provided concerning construction, the proposed development will
consist of single -story, slab -on -grade commercial and retail buildings. Paved parking areas
and access roads will be constructed around the buildings.
Although final site grading plans were not available prior to preparation of this report,
ground floor levels are anticipated to be at or near existing site grades.
Geotechnical Engineering Exploration
GT Land, Inc.
Terracon Project No. 20955160
SITE EXPLORATION
Terracon
The scope of the services performed for this project included site reconnaissance by an
engineering geologist, a subsurface exploration program, laboratory testing and engineering
analysis.
Field Exploration: A total of four test borings were drilled to depths of 15 feet 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 corners. Elevations were
' determined at each boring location using an engineer's level and a temporary benchmark
(TBM) shown on the Site Plan. The accuracy of boring locations and elevations should only
be assumed to the level implied by the methods used.
' Continuous litholo is logs of each boring were recorded b the engineering geologist during
9� 9 9 Y 9 9 9 9� 9
' the drilling operations. At selected intervals, samples of the subsurface materials were
taken by pushing thin -walled Shelby tubes, or by driving split -spoon samplers.
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
two 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 B. 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.
2
' Geotechnical Engineering Exploration
GT Land, Inc.
' Terracon Project No. 20955160
' Selected soil samples were tested for the following engineering properties:
• Water content • Liquid Limit
t • Dry density • Plasticity Index
• Compressive strength • Percent Fines
• Expansion
Terracon
' The significance and purpose of each laboratory test is described in Appendix B. Laboratory
test results are presented on the boring logs and were used for the geotechnical engineering
analyses, and the development of preliminary 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 is a field of harvested sorghum. The southwest corner of the site is occupied by
a two-story brick building (Harmony School) and a small frame residence. An irrigation ditch
approximately 10 feet wide by 4 feet deep cuts across the southwest corner of the site,
northeast of these two structures. The ditch had approximately 2 feet of water in it at the
time of our field exploration. The area exhibits slight surface drainage to the north-
northeast. The property is bordered by the Sunstone Subdivision to the north, Harmony
Road to the south, a trailer park to the east and Timberline Road to the west.
SUBSURFACE CONDITIONS
Soil Conditions: As presented on the boring logs, the subsurface soils were encountered
in order of increasing depth as follows:
• Topsoil. A '/2 foot layer of topsoil was encountered at the surface of the test
borings. The topsoil has been penetrated by root growth and organic matter.
• Lean Clay with Sand. A layer of brown lean clay with sand was encountered below
' the topsoil in test boring 2 and extends to a depth of 21/2 feet. This clay is moist
and contains moderate quantities of sand.
3
Geotechnical Engineering Exploration
GT Land, Inc.
Terracon Project No. 20955160
Terracon
• Lean Clay. A layer of lean clay was encountered below the topsoil and/or lean clay
with sand in all four test borings and extends to the depths explored. The lean clay
is moist to wet with depth and contains minor quantities of sand.
Field and Laboratory Test Results: Field test results indicate the clay soils are stiff to
medium stiff above the water table and soft near or below the water table.
Laboratory test results indicate that the clay soils at anticipated foundation bearing depth
have low to moderate expansive potential.
Groundwater Conditions: Groundwater was observed at depths of approximately 10 to
10'/2 feet in three of the test borings at the time of the field exploration. When checked
two days after drilling, groundwater was measured at depths of approximately 9'/z to 12
feet in all four test borings. These observations represent only current groundwater
conditions, and may not be indicative of other times, or at other locations. Groundwater
levels can be expected to fluctuate with varying seasonal and weather conditions.
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.
Earthwork:
• Site Clearincg:
1. Strip and remove existing vegetation, debris, and other deleterious materials
from proposed building areas. All exposed surfaces should be free of mounds
and depressions which could prevent uniform compaction.
0
Geotechnical Engineering Exploration
GT Land, Inc.
Terracon Project No. 20955160
Terracon
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, should be
scarified to a minimum depth of 8 inches, conditioned to near optimum
moisture content, and compacted.
Foundation Systems: Based on the soil conditions encountered in the test borings, spread
' footing and/or grade beam foundation systems bearing upon undisturbed subsoils and/or
engineered fill are recommended for support of the proposed structures. Preliminary design
' of footings and/or grade beams bearing on the natural clayey strata may use a maximum
bearing capacity in the range of 1,500 to 2,700 psf. The preliminary design bearing
pressures apply to dead loads plus '/z of design live load conditions. Additional testing
' should be done prior to final design. In addition, the footings and/or grade beams should
be sized to maintain a minimum dead load pressure in the range of 500 to 900 psf.
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
' 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
1 to provide a basis for evaluating subsurface conditions.
5
� I
' Geotechnical Engineering Exploration
GT Land, Inc.
Terracon Project No. 20955160
Terracon
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.
1
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LOG OF BORING No. 1 Page 1 of 1
CLIENT
ARCHITECT / ENGINEER
GT Land Inc.
RBD Inc.
SITE Timberline Road & Harmony Road
PROJECT
Fort Collins, Colorado
Harmony School Shops
SAMPLES
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WATER LEVEL OBSERVATIONS
BORING STARTED 9-18-95
Irerracon
BORING COMPLETED 9-18-95
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LOG OF BORING No. 2
Page 1 of 1
CLIENT
ARCHITECT i ENGINEER
GT Land Inc.
RBD Inc.
SITE Timberline Road & Harmony Road
PROJECT
Fort Collins, Colorado
Harmony School Shops
SAMPLES
TESTS
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WATER LEVEL OBSERVATIONS
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LOG OF BORING No. 3 Page 1 of 1
CLIENT
ARCHITECT ENGINEER
GT Land Inc.
RBD Inc.
SITE Timberline Road & Harmony Road
PROJECT
Fort Collins, Colorado
Harmony School Shops
SAMPLES
TESTS
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WATER LEVEL OBSERVATIONS
BORING STARTED 9-18-95
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LOG OF BORING No. 4
Page I of 1
CLIENT
ARCHITECT ! ENGINEER
GT Land Inc.
RBD Inc.
SITE Timberline Road & Harmony Road
PROJECT
Fort Collins, Colorado
Harmony School Shops
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
BORING STARTED 9-18-95
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BORING COMPLETED 9-18-95
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DRILLING AND EXPLORATION
DRILLING & SAMPLING SYMBOLS:
R : Ring Barrell - 2.42" I.D., 3" O.D., unless otherwise noted
SS : Split Spoon - 1-Ya" 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 (SM).
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-Blowslft.
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
(4.75mm to 0.075mm)
Silt or Clay
Passing #200 Sieve
(0.075mm)
Irerracon
UNIFIED SOIL CLASSIFICATION SYSTEM
Soil Classification
Criteria for Assigning Group Symbols and Group Names Using Laboratory Test? Group
Group Name'
Symbol
Coarse -Grained Gravels more than Clean Gravels Less Cu > 4 and 1 < Cc <3E GW Well -graded grave IF
Soils more than 50% of coarse than 5% fines' — — —
50% retained on fraction retained on
No. 200 sieve No. 4 sieve Cu < 4 and/or 1 > Cc > 3E GP Poorly graded grave IF
Gravels with Fines Fines classifyas ML or MH GM Silty gravel,G,H
more than 12% finesc
Sands 50% or more Clean Sands Less
of coarse fraction than 5% finesE
passes No. 4 sieve
Fine -Grained Soils Silts and Clays
50% or more Liquid limit less
passes the than 50
No. 200 sieve
Silts and Clays
Liquid limit 50
or more
Fines classify as CL or CH
Cu> 6and 1 <Cc <3E
Cu < 6 and/or 1 > Cc > 3E
Sands with Fines Fines classify as ML or MH
more than 12% fine SD
Fines Classify as CL or CH
inorganic
GC Clayey graveII.G."
SW Well -graded sand'
SP Poorly graded sand'
SM Silty sandG•"•l
SC Clayey sandG•"'
PI > 7 and plots on or above "A line' CL Lean clal
PI < 4 or plots below "A" line' ML Silt K,L,M
organic Liquid limit - oven dried < 0.75 OL Organic clayK•L.M.
Liquid limit - not dried Organic siltK.L,M.o
inorganic
PI plots on or above "A" line CH Fat clayK,L.M
PI lots below "A" line MH Elastic SiltKIN
organic Liquid limit - oven dried
Organic clayK,L.M.P
< 0.75 OH
Liquid limit not dried
Organic siltr,,L.M.0
Or 9
Highly organic soils Primarily organic matter, dark in color, and organic odor
PT Peat
ABased on the material passing the 3-in.
Klf soil contains 15 to 29% plus No. 200, add
(75-mm) sieve
ECu=D601Dio Cc = (D'°) 2
"with sand" or "with gravel", whichever is
'If field sample contained cobbles or
D:o x D6o
predominant.
boulders, or both, add "with cobbles or
Llf 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
'if soil contains > 15% sand, add "with
name.
symbols:
sand" to group name.
'if soil contains > 30% plus No. 200,
"gravelly"
GW-GM well -graded gravel with silt
'If fines classify as CL-ML, use dual symbol
predominantly gravel, add to group
GW-GC well -graded gravel with clay
GP -GM poorly graded gravel with silt
GC -GM, or SC-SM.
"If fines are organic, add "with organic fines"
name.
"PI > 4 and plots on or above "A" line.
"A"
GP -GC poorly graded gravel with clay
to group name.
GPI < 4 or plots below line.
"A"
'Sands with 5 to 12% fines require dual
'If soil contains > 15% gravel, add "with
PPI plots on or above 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
bo
$o
a
X 40
14
Q
z
30
F
U_
M 20
a
10
4
For cloefifieotion of fine—grained spill
OnEnfl—gl'ined fracflon of coana-
proi • r
A.rio;w t F, = a 1. LL 2$.$
then = 0.73 (LL - 20)=
Eamtion of V - line
verticcl of LL = 16 to PI 7,
then ' = 0.9 (LL
II
����• '
•�%.'� �
Ox
Q�
�\
I
0
Off'
MH OR
OH
ML OR OL
CL-ML
0
0 10 16 20 30 40 Y� 60 70 °0 90 100 11C
LIQUID LIMIT (LL)
Berracon
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
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
Used to determine the capacity of soil or rock to conduct a
Groundwater
Permeability
liquid or as.
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
Merracon
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
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
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.
Irerracon
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.
Irerracon