HomeMy WebLinkAboutB15-0199_Sub Soil Study_1434050400.pdf Hepworth-Pawlak Geotechnical,Inc.
5020
Geetech Glen County Road 154
Glenwood Springs,Colorado 81601
Phone:970-945-7988
Fax:970-945-8454
hpgeo@hpgeotech.com
SUBSOIL STUDY
FOR FOUNDATION DESIGN
PROPOSED RESIDENCES
LOT 8, FILING 4
LION'S RIDGE SUBDIVISION
ASPEN GROVE LANE
VAIL, COLORADO
JOB NO. 101 549
OCTOBER 17, 2002
PREPARED FOR:
DR. ROBERT SELBY
4380 NORTH CAMPBELL AVENUE, SUITE 200
TUSCON, ARIZONA 85718
HEPWORTH- PAWLAK GEOTECHNICAL, INC.
October 17, 2002
Dr. Robert Selby
4380 North Campbell Avenue, Suite 200
Tucson, Arizona 85718 Job No. 101 549
Subject: Report Transmittal, Subsoil Study for Foundation Design, Proposed
Residences, Lot 8, Filing 4, Lion's Ridge Subdivision, Aspen Grove
Lane, Vail, Colorado
Dear Dr. Selby:
As requested, we have conducted a subsoil study for the proposed development at the
subject site.
Subsurface conditions encountered in the exploratory borings drilled in the proposed
building areas consist of 1 foot of topsoil and 2 to 31 feet of mainly clayey sand
overlying sandstone bedrock in the Lot 8B building envelope and 1 foot of topsoil
overlying 141 to 161/2 feet of mainly clayey sand over sandstone bedrock in the Lot 8A
building envelope. Groundwater was not encountered in the borings.
The proposed residences can be founded on spread footings placed on the natural
Jsubsoils or bedrock and designed for an allowable bearing pressure of 2000 psf.
Recommendations for design and construction of the proposed driveway are included in
this report.
The report which follows describes our exploration, summarizes our findings, and
presents our recommendations. It is important that we provide consultation during
design, and field services during construction to review and monitor the implementation
of the geotechnical recommendations.
If you have any questions regarding this report, please contact us.
Sincerely,
HEPWORTH -PAWLAK GEOTECHNICAL, INC.
Daniel E. Hardin, P.E.
Rev. by: SLP
DEH/djb
J
TABLE OF CONTENTS
PURPOSE AND SCOPE OF STUDY 1
PROPOSED CONSTRUCTION 1
SITE CONDITIONS 2
FIELD EXPLORATION 2
SUBSURFACE CONDITIONS 3
FOUNDATION BEARING CONDITIONS 3
DESIGN RECOMMENDATIONS 4
FOUNDATIONS 4
FOUNDATION AND RETAINING WALLS 5
FLOOR SLABS 6
UNDERDRAIN SYSTEM 7
SITE GRADING 7
SURFACE DRAINAGE 8
DRIVEWAY CONSTRUCTION 8
LIMITATIONS 9
FIGURE 1 - LOCATION OF EXPLORATORY BORINGS
FIGURE 2 - LOGS OF EXPLORATORY BORINGS, LOTS 8A AND 8B
FIGURE 3 - LOGS OF EXPLORATORY BORINGS, ROADWAY
FIGURE 4 - LEGEND AND NOTES
FIGURES 5 AND 6 - SWELL-CONSOLIDATION TEST RESULTS •
TABLE I - SUMMARY OF LABORATORY TEST RESULTS
J
H-P GEOTECH
PURPOSE AND SCOPE OF STUDY
This report presents the results of a subsoil study for the development of two
proposed residences to be located on Lot 8, Filing 4, Lion's Ridge Subdivision, Vail,
Colorado. The project site is shown on Fig. 1. The purpose of the study was to
develop recommendations for the access drive and residential foundation design. The
study was conducted in accordance with our agreement for geotechnical engineering
services to Dr. Robert Selby dated July 9, 2002. Geologic hazards (including rockfall)
at this site have been addressed by others. A preliminary subsoil study for filing 4 was
performed by Chen and Associates under their Job No. 19,418, dated August 15, 1980.
A field exploration program consisting of exploratory borings was conducted to
obtain information on subsurface conditions. Samples of the subsoils and bedrock
obtained during the field exploration were tested in the laboratory to determine their
classification, compressibility or swell and other engineering characteristics. The
results of the field exploration and laboratory testing were analyzed to develop
recommendations for foundation types, depths and allowable pressures for the proposed
building foundations. We have also included recommendations for design of the access
drive. This report summarizes the data obtained during this study and presents our
conclusions, design recommendations and other geotechnical engineering considerations
based on the proposed construction and the subsoil conditions encountered.
PROPOSED CONSTRUCTION
The proposed residences have not been designed. We assume they will be
typical of other residences in the area and consist of two to three story wood frame
structures over crawlspaces or basements. We expect basement and garage floors will
be slab-on-grade. Grading for the structures is assumed to involve cut depths between
about 4 to 15 feet. We assume relatively light foundation loadings, typical of the
proposed type of construction. The proposed access drive will require cut and fill
depths up to 10 feet with some retaining walls.
l When building location, grading and loading information have been developed,
J we should be notified to re-evaluate the recommendations presented in this report.
H-P GEOTECH
2
SITE CONDITIONS
Lot 8 was vacant at the time of our field exploration. A narrow path to the two
building envelopes had been roughed in on the proposed driveway alignment to provide
access to the drill rig. The site slopes down to the south at grades of about 50% in the
driveway area west of the building areas and between 15 and 35% in the building areas.
The site is vegetated with aspen trees, brush, grass and weeds. Sandstone bedrock of
the Mintum Formation outcrops above the driveway west of the Lot 8A building
envelope and below the driveway south of the Lot 8A building envelope, and was
observed in the recent access path cut between Borings 5 and 6. A rockfall mitigation
fence has been installed on the downhill side of the driveway from Aspen Grove Lane
to near the Lot 8A building envelope.
HELD EXPLORATION
The field exploration for the project was conducted on September 4 and 5, 2002.
Seven exploratory borings were drilled at the locations shown on Fig. 1 to evaluate the
subsurface conditions. The borings were advanced with 4 inch diameter continuous
flight augers powered by a track-mounted CME-45 drill rig for Borings 1 to 4 and a
truck-mounted Longyear BK-51HD drill rig for Borings 5 to 7. 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 subsoils 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 and hardness of
the rock. Depths at which the samples were taken and the penetration resistance values
are shown on the Logs of Exploratory Borings, Figs. 2 and 3. The samples were
returned to our laboratory for review by the project engineer and testing.
H-P GEOTECH
- 3 -
f1 SUBSURFACE CONDITIONS
Graphic logs of the subsurface conditions encountered at the site are shown on
Figs. 2 and 3. The subsoils consist of about 1 foot of topsoil overlying medium dense,
clayey sand and stiff sandy clay with rock fragments. Hard sandstone bedrock was
encountered below the sand and clay at depths of 2 to 41 feet at Lot 8B and 16 to 18
feet at Lot 8A. On-site fill due to recent grading was encountered to depths of 4 to 51h
feet in Borings 5 to 7 along the proposed driveway. The loose fill was underlain by 11/2
to 14 feet of medium dense clayey sand with sandstone bedrock encountered at depths
of 7 to 14 feet in Borings 6 and 5, respectively. The clayey sand at Boring 7 was
underlain by relatively dense clayey sand and gravel containing cobbles and boulders
from 18 feet deep to the bottom of the boring, 31 feet. Drilling in the bedrock with
auger equipment was difficult due to the hardness of the sandstone and drilling refusal
was encountered in the formation.
Laboratory testing performed on samples obtained from the borings included
natural moisture content, density, Atterberg limits and percent finer than sand size
gradation analyses. Results of swell-consolidation testing performed on relatively
undisturbed drive samples of the clay and sand soils, presented on Figs. 5 and 6,
indicate low to moderate compressibility under conditions of loading and wetting. A
shallow sample of clay from Boring 2 showed a moderate expansion potential when
wetted. The other samples showed low to no collapse potential (settlement under
constant load) when wetted. Atterberg limits testing indicates that the clay portion of
the soils have low plasticity. The laboratory testing is summarized in Table I.
No free water was encountered in the borings at the time of drilling or when
checked almost three weeks later on September 23, 2002. The subsoils were slightly
moist to moist.
FOUNDATION BEARING CONDITIONS
Spread footing foundations should be suitable for support of residential
construction on Lot 8. Shallow sandstone bedrock was encountered at Lot 8B at depths
H-P GEOTECH
4
'D of 2 to 4 feet. The bedrock should provide relatively high bearing capacity but will be
difficult to excavate and chipping or blasting will likely be required. The bedrock was
encountered at 16 to 18 feet deep on Lot 8A and may be encountered near the bottom of
deep foundation excavations. The overlying sand and clay soils should provide
moderate bearing capacity with low to moderate settlement potential. The expansive
clay encountered in Boring 2 appears to be an anomaly and should be removed below
building areas if encountered. Recommendations for foundation design are provided
below.
DESIGN RECOMMENDATIONS
FOUNDATIONS
Considering the subsurface conditions encountered in the exploratory borings
and the nature of the proposed construction, we recommend the residences be founded
i
with spread footings bearing on the natural sand and clay soils or hard sandstone
bedrock.
The design and construction criteria presented below should be observed for a
spread footing foundation system.
1) Footings placed on the undisturbed natural sand and clay soils should be
designed for an allowable soil bearing pressure of 2000 psf. Footings
placed entirely on the sandstone bedrock can be designed for 5000 psf.
Based on experience, we expect settlement of footings designed and
constructed as discussed in this section will be about 1 inch or less.
2) The footings should have a minimum width of 16 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 48 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
H-P GEOTECH
5
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 topsoil, expansive clay and any loose or disturbed soils should be
removed and the footing bearing level extended down to natural sand and
clay soils or bedrock. Holes below footing grade due to bedrock or
boulder removal should be backfilled with concrete or compacted
granular soils. If water seepage is encountered, the footing areas should
be dewatered before concrete placement.
6) A representative of the geotechnical engineer should observe all footing
excavations prior to concrete placement to evaluate bearing conditions.
FOUNDATION AND RETAINING WALLS
Foundation walls and retaining structures 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 50 pcf
for backfill consisting of the on-site soils. Cantilevered retaining structures which are
separate from the residences 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 45 pcf for backfill consisting
of the on-site soils.
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 90% of the
maximum standard Proctor density at a moisture content near optimum. Backfill in
pavement and walkway areas should be compacted to at least 95% of the maximum
H-P GEOTECH
6
standard Proctor density. 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.
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 calculated based on a coefficient of friction of 0.40 for
the sand and clay soils and 0.60 for sandstone bedrock. Passive pressure of compacted
backfill against the sides of the footings can be calculated using an equivalent fluid unit
weight of 350 pcf. The coefficient of friction and passive pressure values recommended
above assume ultimate soil strength. Suitable factors ofsafety 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
Jloads should be compacted to at least 95% of the maximum standard Proctor density at
a moisture content near optimum.
FLOOR SLABS
The natural on-site soils, exclusive of topsoil, are suitable to support lightly
loaded slab-on-grade construction. Expansive clays should be removed from below
floor slab areas. To reduce the effects of some differential movement, 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 basement level 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.
H-P GEOTECH
7
DAll fill materials for support of floor slabs should be compacted to at least 95%
of maximum standard Proctor density at a moisture content near optimum. Required
fill can consist of the on-site granular soils devoid of vegetation, topsoil and oversized
rock.
UNDERDRAIN SYSTEM
Although free water was not encountered during our exploration, it has been our
experience in mountainous areasand where bedrock is shallow that local perched
groundwater may develop during times of heavy precipitation or seasonal runoff.
Frozen ground during spring runoff can also create a perched condition. We
recommend below-grade construction, such as retaining walls, crawlspace and basement
areas, be protected from wetting and hydrostatic pressure buildup by an underdrain
system.
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
9 should be placed at each level of excavation and at least 1 foot below lowest adjacent
fmish 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. The drain gravel backfill should be at least 11/2 feet deep.
SITE GRADING
The risk of construction-induced slope instability at the site appears low
provided cut and fill depths are limited. We assume the cut depths for the basement
level will not exceed one level, about 10 to 15 feet. The bedrock bedding is typically
down into the hillside at the site and near vertical temporary cut slopes in the bedrock
should be feasible. Fills should be limited to about 8 to 10 feet deep. Embankment fills
should be compacted to at least 95% of the maximum standard Proctor density near
optimum moisture content. Prior to fill placement, the subgrade should be carefully
prepared by removing all vegetation and topsoil and compacting to 95% standard
H-P GEOTECH
8
Proctor density. The fill should be benched into the portions of the hillside exceeding
20% grade.
Permanent unretained cut and fill slopes should be graded at 2 horizontal to
1 vertical or flatter and protected against erosion by revegetation or other means. The
risk of slope instability will be increased if seepage is encountered in cuts and flatter
slopes may be necessary. If seepage is encountered in permanent cuts, an investigation
should be conducted to determine if the seepage will adversely affect the cut stability.
This office should review site grading plans for the project prior to construction.
SURFACE DRAINAGE
The following drainage precautions should be observed during construction and
maintained at all times after the residences 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 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 building should be
sloped to drain away from the foundation in all directions. We
recommend a minimum slope of 12 inches in the first 10 feet in unpaved
areas and a minimum slope of 3 inches in the first 10 feet in paved areas.
Free-draining wall backfill should be capped with about 2 feet of the
on-site soils to reduce surface water infiltration.
4) Roof downspouts and drains should discharge well beyond the limits of
all backfill.
DRIVEWAY CONSTRUCTION
The proposed driveway alignment is shown on Fig. 1 and will involve cuts and
l fills up to 10 feet deep. We assume the cut and fill slopes will be retained or will be
sloped at 2 horizontal to 1 vertical or flatter. The western portion of the driveway
H-P GEOTECH
9
crosses existing 2 to 1 slopes and is close to the property line so retaining walls will be
required is this area. Mechanically stabilized earth (MSE) walls could be used for
support of road fill on the downhill side of the road. MSE walls could be used to
support cut slopes on the uphill side of the road but may require more extensive
excavation than other types of retaining systems. Permanent soil nailing orcast-in-
place concrete retaining walls could also be used to support the uphill side of the
driveway. Boulder walls may be appropriate provided cut heights are relatively low
compared to the size of the boulders. Boulder walls should be designed based on a base
width of at least 2/a the wall height. Retaining walls should include drainage behind the
wall and should be designed based on the recommendations contained in the Foundation
and Retaining Walls section of this report. Lateral loading for retaining walls with a 2
horizontal to 1 vertical backslope should be taken as 60 pcf equivalent fluid unit weight.
MSE and soil nail walls are typically designed and built by a specialty contractor. A
strength angle of 30° can be used for the on-site sand and clay soils compacted to at
least 95% of the maximum standard Proctor density. A strength angle of 32° can be
Jused for the in-place soils. A cohesion of zero should be taken for both the compacted
and natural soil condition. The average moist density of the in-place soils is about 110
pcf.
We recommend a pavement section of 3 inches of asphalt over 6 inches of 3/4-
inch road base for preliminary design of the proposed driveway.
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 expressed 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 Fig. 1, the proposed type of construction and our experience
in the area. 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
H-P GEOTECH
- 10 -
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 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.
Sincerely,
HEPWORTH - PAWLAK GEOTECHNICAL, INC.
Daniel E. Hardin, P.E.
Reviewed by:
Steven L. Pawlak, P.E.
DEH/djb
attachments
cc: Peak Land Consultants -Attn: George Mussman
Vanderwalker Construction - Attn: Bob Vanderwalker
H-P GEOTECH
LOT 7 w cot
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2 ASPEN 1 1 ' \ \ I I SPACE
GROVE \ \ 1 11 11 1 1 1
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\ APPROXIMATE SCALE
\ 1 130:
1 1 1 \ \ 1" = 80'
1 1 \ \ \
\ \ 1 1 \\ \ 1 \ \\
PROPOSED \ \ 1 1 \ \ \ \, \
ROADWAY
(SHADED)
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8470
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I 101 549 HEPWORTH—PAWLAK LOCATION OF EXPLORATORY BORINGS Fig. 1
GEOTECHNICAL, INC.
j „ .
BORING 1 BORING 2 BORING 3 BORING 4
ELEV.= 8490' ELEV.= 8506' ELEV.= 8487' ELEV.= 8498'
O ,� 0 _
N N N
17/12
—
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., . 50/3 • WC=5.8 8/12 —
— Sr,• I DD=100
-200=60 —
111
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' WC=7.8 WC=2.2 ' WC=6.4 5 —
' 15 DD=125 DD=108 D0=114 i —
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-
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— 20 =', 50/11 20 --
_ 25 25
LOT 88 LOT 8A
Note: Explanation of symbols is shown on Fig. 4.
1101 549 HEPWORTH—PAWLAK LOGS OF EXPLORATORY BORINGS Fig 2
GEOTECHNICAL, INC. LOTS 8A AND 8B
) BORING 5 BORING 6 BORING 7
ELEV.= 8453' ELEV.= 8452' ELEV.= 8435'
PROPOSED ROAD
ELEVATION = 8458' PROPOSED ROAD
ELEVATION
0II 0
• rl
— . PROPOSED
ELEVATION ROAD
8/12 - 8/12
• OD=12. ♦ 12/12
— . - S.
5 -20C97
— :1:- 11/12 .j' 7/6,16/6 �'1 23/12 5
• WC=5.4 WC=10.9 we=7.4
DD=90 00=108 • DD=96
–200=49 Nt4. –200=70 –200=59
LL=30 P?:
P1=10 LL=26
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we=8.5
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DNote: Explanation of symbols is shown on Fig. 4.
101 549 1 HEPWORTH—PAWLAK LOGS OF EXPLORATORY BORINGS
GEOTECHNICAL, INC. ROADWAY I Fig. 3
LEGEND:
FILL; on—site clayey sand with topsoil, scattered rock fragments, loose, slightly moist to moist,
brown.
r..
"- TOPSOIL; sandy silty clay, organic, firm, slightly moist to moist, dark brown.
c:�� CLAY AND SAND (CL—SC); sandy silty clay to clayey sand, scattered rock fragments, stiff to
very stiff or medium dense, moist, brown to reddish brown.
pg SAND AND GRAVEL (SC—GC); clayey, with sandy clay layers, cobbles and possible small boulders,
y..l dense, moist, reddish brown.
` SANDSTONE BEDROCK; hard, slightly moist, reddish brown, bedding down into hillside. Minturn
; Formation.
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 17 blows of a 140 pound hammer falling 30 inches were
17x
/12 required to drive the California or SPT sampler 12 inches.
c) Practical drilling refusal.
—> Depth at which boring had caved when checked on September 23, 2002.
NOTES:
1. Exploratory borings were drilled on September 4 and 5, 2002 with a 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 on the site plan provided.
Boring logs are drawn to depth
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 or when checked on September 23,
2002. Fluctuation in water level may occur with time.
7. Laboratory Testing Results:
WC = Water Content ( % )
DD = Dry Density ( pcf )
+4 = Percent retained on No. 4 sieve.
—200 = Percent passing No. 200 sieve.
LL = Liquid Limit ( % )
( 3 PI = Plasticity Index ( % )
I
101 549 HEPWORTH—PAWLAK LEGEND AND NOTES Fig. 4
GEOTECHNICAL, INC.
Moisture Content = 7.8 percent
4 Dry Density = 125 pcf
Sample of: Sandy Clay
• From:Boring 2 at 4 Feet
3
2 •
Expansion
o upon
1 wetting •
0
a
x
L
0
c •
0
N
0 1
a
E
0
2 •
0.1 1.0 10 100
APPLIED PRESSURE — ksf
0
Moisture Content = 2.2 percent
Dry Density = 108 pcf
Sample of: Sandy Silty Clay
From:Boring 3 at 4 Feet
0
1
Compression
upon
c 2 wetting
0
Co
•
N
a0
3
E
0
U
4
5
•
3 0.1 1.0 10 100
I APPLIED PRESSURE — ksf
1101 549 HEP WORTH—PAWLAK SWELL CONSOLIDATION TEST RESULTS Fig. 5
J GEOTECHNICAL, INC.
vr ,
Moisture Content = 8.5 percent
J Dry Density = 115 pcf
Sample of: Clayey Sand
From: Boring 3 at 14 Feet
0
1
��,Compression
g upon
.N 2 wetting
Q
E
v 3
4
0.1 1.0 10 100
APPLIED PRESSURE — ksf
i J1
Moisture Content = 6.4 percent
Dry Density = 114 pcf
Sample of: Clayey Sand
From: Boring 4 at 4 Feet
0
•
1
2
• Compression
(, upon
•
2 • wetting
n
E
0
U
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1101 549 HEPWORTH—PAWLAK SWELL CONSOLIDATION TEST RESULTS Fig. 6
GEOTECHNICAL, INC.
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