HomeMy WebLinkAboutSoils Report 11.30.2015ech
HEPWORTH—PAWLAK GEOTECHNICAL
1-t1n:.
5020 01111.14 1c,,;IJ 154
Glcntcn)J Springs, Col. midi) 81601
Phone: 970-945 -798
Fax: 970.9.15-8454
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GEOTECHNICAL ENGINEERING STUDY
FOR FOUNDATION DESIGN
PROPOSED SITE REDEVELOPMENT
OLD BUFFALO VALLEY PROPERTY
3637 STATE HIGHWAY 82
GARFIELD COUNTY, COLORADO
JOB NO. 113 106A
NOVEMBER 30, 2015
PREPARED FOR:
PARTNERS III, LLC
ATTN: NORM BACHELDOR
353 GOOSE LANE
CARBONDALE, COLORADO 81623
narmaitbaclicIdor@ginai1,coin
Parker 303.841-7119 • Colorado Springs 719.633-5561 • SiI1'erthornc 970-468-1989
TABLE OF CONTENTS
PURPOSE AND SCOPE OF STUDY - 1 -
PROPOSED CONSTRUCTION .. - 1 -
SITE AND GEOLOGIC CONDITIONS - 2 -
FIELD EXPLORATION - 2 -
SUBSURFACE CONDITIONS - 3 -
FOUNDATION BEARING CONDITIONS , - 4 -
DESIGN RECOMMENDATIONS - 4 -
FOUNDATIONS- 4 -
FOUNDATION AND RETAINING WALLS + - 6 -
FLOOR SLABS -7-
UNDERDRAIN SYSTEM - 7 -
SITE GRADING - 8 -
PAVEMENT SECTION - 9 -
SURFACE DRAINAGE - 10 -
LIMITATIONS - 10 -
FIGURE 1 - LOCATION OF EXPLORATORY BORINGS
FIGURE 2 - LOGS OF EXPLORATORY BORINGS
FIGURE 3 - LEGEND AND NOTES
FIGURS 4 AND 5 - SWELL -CONSOLIDATION TEST RESULTS
FIGURE 6 - GRADATION TEST RESULTS
TABLE 1- SUMMARY OF LABORATORY TEST RESULTS
PURPOSE AND SCOPE OF STUDY
This report presents the results of a geotechnical engineering study for the proposed
redevelopment of the old Buffalo Valley property located at 3637 State Highway 82,
Garfield County, Colorado. The project site is shown on Figure 1. The purpose of the
study was to develop recommendations for the foundation design. The study was
conducted as additional services to and in general accordance with our agreement for
geotechnical engineering services to Partners III, LLC dated April 22, 2013. We
previously conducted a geologic hazards review of the subject property and presented our
findings in a report dated April 30, 2013, Job No. 113 106A.
A field exploration program consisting of exploratory borings was conducted to obtain
information on the subsurface conditions. Samples of the subsoils obtained during the
field exploration were tested in the laboratory to determine their classification,
compressibility or expansion potential and other engineering characteristics. The results
of the field exploration and laboratory testing were analyzed to develop recommendations
for building foundation design including types, depths and allowable pressures. This
report summarizes the data obtained during this study and presents our conclusions,
recommendations and other geotechnical engineering considerations based on the
proposed construction and the subsurface conditions encountered.
PROPOSED CONSTRUCTION
The proposed development generally consists of two apartment buildings located
approximately as shown on Figure 1 which will be constructed in place of the existing
buildings. The proposed buildings will be 3 stories with a walkout lower level. Ground
floor of the proposed buildings will be slab -on -grade with cut depths up to about 10 feet.
Parking and drives will be provided around and adjacent to the new buildings at grades
near the existing ground surface. Low retaining walls and graded slopes will be needed
for grade change across the property. We assume relatively light foundation loadings
typical for the apartment buildings.
Job No. 113 106A
Gatech
2
If building locations, grading and loading information change significantly from that
described above, we should be notified to re-evaluate the recommendations presented in
this report.
SITE AND GEOLOGIC CONDITIONS
The site is currently developed with one and two story, wood frame buildings previously
used as a restaurant (Buffalo Valley) and motel. The site slopes moderately down from
the northeast to the southwest with a terraced parking area in the middle of the property.
A small drainage ditch drains to the southwest along the north side of the property. The
property then slopes relatively steep down to an adjacent property on the west and
southwest sides. A recent stockpile of soil is located in the middle terrace area and upper
proposed building site. Where not occupied by buildings or parking lot, the site is
moderately vegetated with grass, shrubs and trees. The site is generally bordered to the
east by County Road 154 and Highway 82, to the north by the Mountain View Church
property, to the west by residential properties and to the south by a trailer park
development.
Potential geologic hazard impacts to the property were evaluated and presented in our
preliminary review report dated April 30, 2013. Based on our review, there are no
potential geologic hazards that could make development of the property infeasible. Our
previous report should be referenced for more specific geologic conditions information.
FIELD EXPLORATION
The field exploration for the project was conducted on November 11, 2015. Five
exploratory borings were drilled at the locations shown on Figure 1 to evaluate the
subsurface conditions. A sixth proposed boring (Boring 3) could not be drilled due to
underground utility conflicts. The borings were drilled with 4 -inch diameter continuous
Job No. 113 106A
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flight augers powered by a truck -mounted CME -45B drill rig. The borings were logged
by a representative of Hepworth-Pawlak Geotechnical, Inc.
Samples of the subsoils were taken with 1% inch and 2 inch I.D. spoon samplers. The
samplers were driven into the subsurface materials at various depths with blows from a
140 pound hammer falling 30 inches. This test is similar to the standard penetration test
described by ASTM Method D-1586. The penetration resistance values are an indication
of the relative density or consistency of the subsoils. Depths at which the samples were
taken and the penetration resistance values are shown on the Logs of Exploratory
Borings, Figure 2. The samples were returned to our laboratory for review by the project
engineer and testing.
SUBSURFACE CONDITIONS
Graphic logs of the subsurface conditions encountered in the borings at the site are shown
on Figure 2. The subsoils encountered, below asphalt pavement materials at Borings 1
and 2 and at ground surface of the other borings, generally consist of stiff, sandy to very
sandy silty clay with scattered gavel (alluvial fan deposits) down to depths of about 3 to 4
feet in the lower proposed building site and to depths of about 13 to 17 feet in the upper
proposed building site. Underlying the clay soils was dense, coarse granular soils (river
gravel deposits). Drilling in the coarse granular soils was difficult due to the cobbles and
probable boulders and drilling refusal was encountered in the deposit.
Laboratory testing performed on samples obtained from the borings included natural
moisture content and density, gradation analyses and liquid and plastic limits. The results
of swell -consolidation testing performed on two samples of the clay soils, shown on
Figures 4 and 5, indicate low to moderate compressibility under conditions of loading and
wetting. The sample from Boring 5 at 10 feet showed a low collapse potential (settlement
under constant load) when wetted. Results of gradation analyses performed on a small
diameter drive sample (minus 1'/2 inch fraction) of the coarse granular soils are shown on
Figure 6. The laboratory testing is summarized in Table 1.
Job Pio. 113 106A
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4
No free water was encountered in the borings at the time of drilling and the soils were
typically slightly moist with the clay soils being moist with depth.
FOUNDATION BEARING CONDITIONS
The relatively dense, natural granular soils and stiff clay soils are suitable for support of
the apartment buildings. Spread footings placed on these materials should have Iow to
moderate bearing capacity for the clay and granular soils, respectively, with expected
relatively low settlement potential. It appears that the upper proposed building will
encounter the clay soils at cut depth and the lower proposed building will encounter the
dense gravel soils at cut depth. Fill material and debris from the existing development
should be completely removed from beneath the proposed building areas: Structural fill
can be used to reestablish design bearing levels. The structural fill can consist of the on-
site granular soils provided they are processed to a relatively well graded material and
devoid of organics, construction debris and rock larger than about 5 inches. Excavation
and grading along the downhill side of the lower building should be carefully planned to
maintain stability and not oversteepen the embankment.
DESIGN RECOMMENDATIONS
FOUNDATIONS
Considering the subsurface conditions encountered in the exploratory borings and the
nature of the proposed construction, we recommend the buildings be founded with spread
footings bearing on the natural granular soils, clay soils or compacted structural fill.
The design and construction criteria presented below should be observed for a spread
footing foundation system.
1) Footings pined on the coarse granular soils or compacted structural fill
should be designed for an allowable bearing pressure of 2,500 psf.
Footings placed on the clay soils should be designed for an allowable
bearing pressure of 1,500 psf.
Job No. 113 106A
Based on experience, we expect initial
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settlement of footings designed and constructed as discussed in this section
will be up to about 1 inch. Additional differential settlement on the order
of 1/2 to 1 inch could occur if the clay bearing soils are wetted. The
settlements could also be differential between clay and granular soils and
variable bearing soil conditions within a single building should be avoided
as much as practical.
2) The footings should have a minimum width of 18 inches for continuous
walls and 2 feet for isolated pads.
3) Exterior footings and footings beneath unheated areas should be provided
with adequate soil cover above their bearing elevation for frost protection.
Placement of foundations at least 36 inches below exterior grade is
typically used in this area.
4) Continuous foundation walls should be reinforced top and bottom to span
local anomalies such as by assuming an unsupported length of at least 12
feet. Foundation walls acting as retaining structures should also be
designed to resist lateral earth pressures as discussed in the "Foundation
and Retaining Walls" section of this report.
5) The existing fill, topsoil, debris and any loose or disturbed soils should be
removed to expose the natural granular soils or clay soils. The exposed
soils should then be moistened and compacted.
Voids created by boulder
removal should be backfilled with structural till or with concrete. The
structural fill should consist of a relatively well graded granular material
limited to a depth of about 6 feet below footing bearing level and
compacted to at least 98% of standard Proctor density (ASTM —D 698) at
near optimum moisture content. The areas stripped of the existing fill soils
should be observed prior to placing structural fill and the structural fill
evaluated for compaction by a representative of the geotechnical engineer.
6) A Site Class C can be assumed for building seismic design based on Table
1613.5.2 of the 2009 IBC.
7) A representative of the geotechnical engineer should observe all footing
excavations prior to concrete placement to evaluate bearing conditions.
Job No. 113 106A
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6
FOUNDATION AND RETAINING WALLS
Foundation walls and retaining structures up to about 12 feet high which are laterally
supported and can be expected to undergo only a slight amount of deflection should be
designed for a lateral earth pressure computed on the basis of an equivalent fluid unit
weight of at least 55 pcf for backfill consisting of the on-site soils. Cantilevered retaining
structures which are separate from the buildings and can be expected to deflect
sufficiently to mobilize the full active earth pressure condition should be designed for a
lateral earth pressure computed on the basis of an equivalent fluid unit weight of at least
45 pcf for backfill consisting of the on-site soils. Backfill should not contain organics,
debris and rock larger than about 5 inches.
All foundation and retaining structures should be designed for appropriate hydrostatic and
surcharge pressures such as adjacent footings, traffic, construction materials and
equipment. The pressures recommended above assume drained conditions behind the
walls and a horizontal backfill surface. The buildup of water behind a wall or an upward
sloping backfill surface will increase the lateral pressure imposed on a foundation wall or
retaining structure.
An underdrain should be provided to prevent hydrostatic pressure
buildup behind walls.
Backfill should be placed in uniform lifts and compacted to at least 95% of the maximum
standard Proctor (ASTM -D698) density at a moisture content near optimum. Care should
be taken not to overcompact the backfill or use large equipment near the wall, since this
could cause excessive lateral pressure on the wall. Some settlement of deep foundation
wall backfill should be expected, even if the material is placed correctly, and could result
in distress to facilities constructed on the backfill. Use of a select granular wall backfill
compacted to at least 98% of standard Proctor density will help reduce the settlement
potential.
The lateral resistance of foundation or retaining wall footings will be a combination of the
sliding resistance of the footing on the foundation materials and passive earth pressure
against the side of the footing. Resistance to sliding at the bottoms of the footings can be
Job No. 113 106A
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calculated based on a coefficient of friction of 0.50 for the coarse granular soils and 0.30
for the clay soils. Passive pressure of compacted backfill against the sides of the footings
can be calculated using an equivalent fluid unit weight of 400 pcf for granular soils and
300 pcf for clay soils. The coefficient of friction and passive pressure values
recommended above assume ultimate soil strength. Suitable factors of safety should be
included in the design to limit the strain which will occur at the ultimate strength,
particularly in the case of passive resistance. Fill placed against the sides of the footings
to resist lateral loads should be compacted to at least 95% of the maximum standard
Proctor density at a moisture content near optimum.
FLOOR SLABS
The natural soils and properly constructed structural fill are suitable to support lightly
loaded slab -on -grade construction. To reduce the effects of some differential movement,
non-structural floor slabs should be separated from all bearing walls and columns with
expansion joints which allow unrestrained vertical movement. Floor slab control joints
should be used to reduce damage due to shrinkage cracking. The requirements for joint
spacing and slab reinforcement should be established by the designer based on experience
and the intended slab use. A minimum 4 inch layer of free -draining gravel should be
placed beneath below basement slabs to facilitate drainage. This material should consist
of minus 2 inch aggregate with at least 50% retained on the No. 4 sieve and less than 2%
passing the No. 200 sieve.
Fill materials placed for support of floor slabs above footing bearing level should be
compacted to at least 95% of maximum standard Proctor (ASTM- D 698) density at a
moisture content near optimum. Required fill can consist of the on-site soils devoid of
vegetation, topsoil, debris and oversized rock.
UNDERDRAIN SYSTEM
Although groundwater was not encountered during our exploration, it has been our
experience in the area and where clay soil is present that local perched groundwater can
develop during times of heavy precipitation or seasonal runoff. Frozen ground during
Job No. 113 106A
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spring runoff can create a perched condition. We recommend below -grade construction,
such as retaining walls and basement areas, be protected from wetting and hydrostatic
pressure buildup by an underdrain system. Building floor slabs constructed at to above
finish exterior grade should not need a perimeter subdrain.
The drains should consist of drainpipe placed in the bottom of the wall backfill
surrounded above the invert level with free -draining granular material. The drain should
be placed at each level of excavation and at least 1 foot below lowest adjacent finish
grade and sloped at a minimum 1% to a suitable gravity outlet. Free -draining granular
material used in the underdrain system should contain less than 2% passing the No. 200
sieve, less than 50% passing the No. 4 sieve and have a maximum size of 2 inches.
SITE GRADING
Excavation of the uphill side of the buildings could be relatively extensive and with a risk
of construction -induced slope instability. We assume the uphill cut slope will be retained
with the foundation wall of the buildings and designed for earth pressure and additional
surcharge loading where needed. We assume cut and fill depths throughout the project
will be about 10 feet or less and fill will not be placed on the steep slopes. Embankment
fill slopes should be compacted to at least 95% of the maximum standard Proctor
(ASTM -D698) density near optimum moisture content. Prior to fill placement, the
subgrade should be carefully prepared by removing all vegetation, topsoil, debris and
existing fill, and compacting to at least 95% of the maximum standard Proctor density.
The fill should be benched into slopes that exceed 20% grade. The on-site soils should be
selectively excavated and processed, including sorting or crushing as needed, to achieve a
relatively well graded material with less than 35% passing the No. 200 sieve and 5 -inch
maximum size. If existing fill is left in-place, such as within pavement areas, it should be
evaluated for suitability of material type and compaction at the time of construction.
Crushed concrete (if used) should have a maximum size of 3 inches and combined on a
one to one ratio with CDOT Class 6 aggregate base course where used as structural
backfill. Permanent unretained cut and fill slopes should be graded at 2 horizontal to 1
Job No. 113 106A
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vertical or flatter and protected against erosion by revegetation or other means. This
office should review site grading plans for the project prior to construction.
PAVEMENT SECTION
We expect that asphalt pavement will be used for the proposed driveways and parking
areas. Traffic loadings have not been provided. The subgrade soils encountered at the
site mainly consist of low plasticity, silty sandy clay which is considered a poor support
for pavement sections. Structural fill needed for the pavement construction should
consist of granular soil. The clay soils encountered on-site is estimated to have a
minimum Hveem stabilometer `R' value of 8. Based on our experience, a 18 kip EDLA
of 15 for driveways and 5 for parking areas, a Regional Factor of 2.0 and a serviceability
index of 2.0, we recommend the minimum pavement section thickness consist of 3 inches
of asphalt on 8 inches of base course. In clay subgrade soil areas, a minimum 12 -inch
thick subbase layer of CDOT Class 2 base course or processed onsite coarse granular
soils should be used under the pavement section given above. As an alternative to asphalt
pavement in areas of concentrated truck loading (such as at trash enclosures) or tight
turning movements, the pavement section should consist of at least 6 inches of portland
cement concrete on 4 inches of aggregate base course. Once traffic loadings are better
known, we should review our pavement section recommendations.
The asphalt should be a batched hot mix, approved by the engineer and placed and
compacted to the project specifications. The base course should meet CDOT Class 6
specifications. All base course and subbase materials and required subgrade fill should be
compacted to at least 95% of the maximum standard Proctor density at a moisture content
within 2% of optimum. The section thicknesses assume structural coefficients of 0.12 for
aggregate base course, 0.44 for asphalt surface and design compressive strength of 4,500
psi for portland cement concrete. The material properties and compaction should be in
accordance with the project specifications.
Required fill to establish design subgrade level should consist of suitable granular soils
consistent with the project specifications. Prior to fill placement the subgrade should be
stripped of unsuitable soils, scarified to a depth of 8 inches, adjusted to near optimum
Job No. 113 106A
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moisture content and compacted to at least 95% of standard Proctor density. The
subgrade should be proofrolled. Areas that deflect excessively should be corrected before
placing pavement materials. The subgrade improvements and placement and compaction
of base and asphalt materials should be monitored on a regular basis by a representative
of the geotechnical engineer.
SURFACE DRAINAGE
Proper surface grading and drainage will be important to the satisfactory performance of
the constructed facilities. The following drainage precautions should be observed during
construction and maintained at all times after the buildings have been completed:
1) Inundation of the foundation excavations and underslab areas should be
avoided during construction.
2) Exterior backfill should be adjusted to near optimum moisture and
compacted to at least 95% of the maximum standard Proctor (ASTM -D
698) density in pavement and slab areas and to at least 90% of the
maximum standard Proctor density in landscape areas.
3) The ground surface surrounding the exterior of the buildings should be
sloped to drain away from the foundation in all directions. We
recommend a minimum slope of 6 inches in the first 10 feet in unpaved
areas and a minimum slope of 21 inches in the first 10 feet in paved areas.
Free -draining wall backfill should be capped with at least 2 feet of the on-
site finer graded soils to reduce surface water infiltration.
4) Roof downspouts and drains should discharge well beyond the limits of all
backfill.
LIMITATIONS
This study has been conducted in accordance with generally accepted geotechnical
engineering principles and practices in this area at this time. We make no warranty either
express or implied. The conclusions and recommendations submitted in this report are
based upon the data obtained from the exploratory borings drilled at the locations
indicated on Figure 1, the proposed type of construction and our experience in the area.
Job No. 113 106A
Gertech
Our services do not include determining the presence, prevention or possibility of mold or
other biological contaminants (MOBC) developing in the future. If the client is
concerned about MOBC, then a professional in this special field of practice should be
consulted. Our findings include interpolation and extrapolation of the subsurface
conditions identified at the exploratory borings and variations in the subsurface
conditions may not become evident until excavation is performed. If conditions
encountered during construction appear different from those described in this report, we
should be notified so that re-evaluation of the recommendations may be made.
This report has been prepared for the exclusive use by our client for design purposes. We
are not responsible for technical interpretations by others of our information. As the
project evolves, we should conduct additional subsurface exploration and provide
continued consultation and field services during construction to review and monitor the
implementation of our recommendations, and to verify that the recommendations have
been appropriately interpreted. Significant design changes may require additional
analysis or modifications to the recommendations presented herein. We recommend on-
site observation of excavations and foundation bearing strata and testing of structural fill
by a representative of the geotechnical engineer.
Respectfully Submitted,
HEPWORTH - PAWLAK GEOTECHNICAL, INC.
Steven L. Pawlak,
Reviewed by:
Daniel E. Hardin, P.E.
SLP/ksw
cc: Z -Group — Seth Hmielowski (seth@zgrouparchitects.com)
Job No. 113 106A
Gtech
APPROXIMATE SCALE
1" = 50'
\
EXISTING
BUILDING
(SHADED)
N.
6b-
N-..,\S$$� \ \
N.
N.
COUNTY ROAD 154
5890- -
/
\ PROPOSED PARKING LOT /
5885
`B RING 5
AL
•
BORING 1
PROPOSED PARKING LOT
5875
PROPOSED PARKING LOT
BORING 2
•
EXISTING
BUILDING
(SHADED)
BORING 4 •
EXISTING
BUILDING
(SHADED)
PROPOSED
BUILDING
BORING 3
(NOT DRILLED)
•
LOCATION OF EXPLORATORY BORINGS
Figure 1
LL
a
a)
0
0
5
10
15
BORING 1
ELEV.= 5872'
BORING 2
ELEV.= 5872'
1111
222 15/12
WC= 16.3
9/6,50/6 DD=110
WC=15.7 .. -200=66
DD=112 UC— 6,300
50/6 36/6,50/2
WC=2.9
DD=111
+4=54
-200=11
BORING 4
ELEV.= 5880'
18/12
WC=15.6
DD=111
-200=81
LL=26
PI=6
8/12
WC=15.2
DD=103
63/12
BORING 5
ELEV.= 5886'
12/12
9/12
WC=5.8
DD=107
-200=45
8/12
WC=9.3
DD= 105
11/12
BORING 6
ELEV.= 5883'
0
11/12
14/12 5
WC=10.6
DD=115
-200=69 —
8/12 10
WC=16.3
DD=109
-200=67
15
20 20
Note: Explanation of symbols is shown on Figure 3.
L
r
a)
113106A
LOGS OF EXPLORATORY BORINGS
Figure 2
r
LEGEND:
1111
15/12
T
ASPHALT PAVEMENT; overlying base course.
CLAY (CL); sandy to very sandy and silty, scattered gravel, stiff, slightly moist to moist with depth, red, low
plasticity,
GRAVEL AND COBBLES (GM -GP); slightly silty, sandy, dense, slightly moist, brown, rounded rock.
Relatively undisturbed drive sample; 2 -inch I.D. California liner sample.
Drive sample; standard penetration test (SPT), 1 3/8 inch I.D. split spoon sample, ASTM D-1586.
Drive sample blow count; indicates that 15 bows of a 140 pound hammer falling 30 inches were
required to drive the California or SPT sampler 12 inches.
Practical drilling refusal.
NOTES:
1. Exploratory borings were drilled on November 11, 2015 with 4 -inch diameter continuous flight power auger.
2. Locations of exploratory borings were measured approximately by pacing from features shown on the site plan
provided.
3. Elevations of exploratory borings were obtained by interpolation between contours shown on the site plan provided.
4. The exploratory boring locations and elevations should be considered accurate only to the degree implied by the
method used.
5. The lines between materials shown on the exploratory boring logs represent the approximate boundaries between
material types and transitions may be gradual.
6. No free water was encountered in the borings at the time of drilling. Fluctuation in water level may occur with time.
7. Laboratory Testing Results:
WC = Water Content (%)
DD = Dry Density (pcf)
+4 = Percent retained on the No. 4 sieve
-200 = Percent passing No. 200 sieve
LL = Liquid Limit (%)
PI = Plasticity Index (%)
UC = Unconfined Compressive Strength (psf)
113106A
LEGEND AND NOTES
Figure 3
Compression %
Compression %
0
1
2
3
4
0
1
2
3
Moisture Content = 15.7 percent
Dry Density = 112 pcf
Sample of: Sandy Silty Clay
From: Boring 1 at 2 2 Feet
No movement
upon
wetting
0.1
1.0 10
APPLIED PRESSURE - ksf
100
Moisture Content = 15.2 percent
Dry Density = 103 pcf
Sample of: Sandy Silty Clay
From: Boring 4 at 5 Feet
Na movement
upon
westing
0.1
1.0 10
APPLIED PRESSURE - ksf
100
113106A
H
Hepworth—Pawlak Geatechnicfll
SWELL -CONSOLIDATION TEST RESULTS
Figure 4
Compression %
Compression %
0
1
2
3
4
0
1
2
3
4
Moisture Content = 9.3 percent
Dry Density =. 105 pcf
Sample of: Sandy Silt and Clay
From: Boring 5 at 10 Feet
Compression
upon
wetting
0.1
1.0 10
APPLIED PRESSURE - ksf
100
Moisture Content = 16.3 percent
Dry Density = 109 pcf
Sample of: Sandy Silty Clay
From: Boring 6 at 10 Feet
Compression
upon
wetting
0.1
.0 10
APPLIED PRESSURE - ksf
100
I-IYDROMFTTR ANALYSIS
TIME READINGS U.S. STANDARD SERIES
0 45 MIN 15 MIN. 60MIN19MIN.4 MIN. 1 MIN. #200 #100 #50 #30 #16 #8
SIEVE ANALYSIS
#4
10
20
30
40
50
60
70
80
90
100
CLEAR SQUARE OPENINGS I
3/8' 3/4" 1 1/2' 3" 5'6" 8" 100
t
r
1
�i
1
.1
001 .002 .005 .009 .019 .037 .074 .150
.300 .600 1.18 2.36
DIAMETER OF PARTICLES IN MILLIMETERS
4.75 9.5 19.0
12.5
37.5
76.2 152 203
127
CLAY TO SILT
SAND GRAVEL
PI B$
I ACEOLL e 1 COAE FINE J COARSE
COBBLES
GRAVEL 54 %
LIQUID LIMIT
SAND 35 %
SILT AND CLAY 11 %
PLASTICITY INDEX %
SAMPLE OF: Slightly Silty Sandy Gravel FROM: Boring 2 at 5 Feet
90
80
70
60
50
40
30
20
10
0
RCE PA e
113 106A
GRADATION TEST RESULTS
Figure 6
Job No. 113 106A
SOIL OR
BEDROCK TYPE
Sandy Silty Clay
f 6,300 C Sandy Silty Clay 11
Slightly Silty Sandy Gravel
Sandy Silt and Clay
Sandy Silty Clay
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-- UNCONFINED
COMPRESSIVE
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ATTERBERG LIMITS
LIQUID PLASTIC
LIMIT INDEX
(%) (%)
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