HomeMy WebLinkAboutHPK 180606 Soils Report copy.pdf H-P KU MAR5020 County Road 154
Glenwood Springs, CO 81601
Geotechnical Engineering I Engineering Geology Phone: (970)945-7988
Materials Testing I Environmental Fax:(970)945-8454
Email: hpkglenwood@kumarusa.com
Office Locations: Parker,Glenwood Springs,and Silverthorne,Colorado
SUBSOIL STUDY
FOR FOUNDATION DESIGN
PROPOSED DUPLEX RESIDENCE
LOT 8,BLOCK 1, GORE CREEK SUBDIVISION
5128 GROUSE LANE
VAIL, COLORADO
PROJECT NO. 18-7-252
JUNE 6, 2018
PREPARED FOR:
STAN JERANKO
11367 RANCH RESERVE PARKWAY
DENVER, COLORADO 80234
(pwdrhnd@aol.com)
TABLE OF CONTENTS
PURPOSE AND SCOPE OF STUDY - 1 -
PROPOSED CONSTRUCTION - 1 -
SITE CONDITIONS - 2 -
FIELD EXPLORATION - 2 -
SUBSURFACE CONDITIONS - 2 -
FOUNDATION BEARING CONDITIONS - 3 -
DESIGN RECOMMENDATIONS -4 -
FOUNDATIONS -4 -
FOUNDATION AND RETAINING WALLS - 5 -
FLOOR SLABS - 6 -
UNDERDRAIN SYSTEM - 7 -
SITE GRADING - 8
SURFACE DRAINAGE - 8 -
LIMITATIONS - 9 -
FIGURE 1 - LOCATION OF EXPLORATORY BORINGS
FIGURE 2 - LOGS OF EXPLORATORY BORINGS
FIGURE 3 - LEGEND AND NOTES
FIGURE 4 - SWELL-CONSOLIDATION TEST RESULTS
FIGURES 5 and 6 - GRADATION TEST RESULTS
TABLE 1- SUMMARY OF LABORATORY TEST RESULTS
H-PkKUMAR
Project No. 18-7-252
PURPOSE AND SCOPE OF STUDY
This report presents the results of a subsoil study for a proposed duplex residence to be located
on Lot 8, Block 1, Gore Creek Subdivision, 5128 Grouse Lane, Vail, 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 in accordance with our proposal for geotechnical
engineering services to Stan Jeranko dated April 3, 2018.
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
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 foundation. 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 subsurface conditions
encountered.
PROPOSED CONSTRUCTION
An existing duplex residence on the lot will be removed and a new duplex residence constructed.
The proposed building will be primarily a two story wood frame structure over a walkout
basement level occupying most of the western half of the lot as shown on Figure 1. Ground
floors will be slab on grade. Grading for the structure is expected to require cut depths between
about 3 to 15 feet. We assume relatively light foundation loadings, typical of the proposed type
of construction.
If building loadings, location or grading plans change significantly from those described above,
we should be notified to re-evaluate the recommendations contained in this report.
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Project No. 18-7-252
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SITE CONDITIONS
The site is currently occupied with the existing duplex residence located in the southern and
western parts of the lot near Grouse Lane. The site has been graded some for the existing
development. The terrain is steep to moderately steeply sloping hillside below Grouse Lane.
The ground slope is down to the northeast/north at grades from about 40 to 50% decreasing to
about 10 to 15% in the northern part of the lot. Elevation difference across the proposed building
foot-print is about 20 feet and across the lot about 30 feet. The lot is bordered on the east by
Gore Creek and there is a paved access drive to Lot 7 in the eastern part of the lot. The building
vegetation consists of landscaped grasses and natural fir trees, weeds and grasses.
FIELD EXPLORATION
The field exploration for the project was conducted on April 17, 2018. Three exploratory
borings were drilled at the locations shown on Figure 1 to evaluate the subsurface conditions.
The borings were advanced with 4-inch diameter continuous flight augers powered by a truck-
mounted CME-45B drill rig. The boring locations were limited due to the existing building and
steep terrain. Borings 2 and 3 were drilled on the lower portion of the lot and Boring 1 was
drilled in the upper part of the lot near Grouse Lane. The borings were logged by a
representative of H-P/Kumar.
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. 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 at the site are shown on Figure 2. The
subsoils encountered, below about 8 feet of fill at Boring 1 or about 1 to 3 feet of organic topsoil
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Project No. 18-7-252
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at Borings 2 and 3, consisted of medium dense,clayey silty sand with scattered gravel and
cobbles underlain at depths from about 41/2 to 121/2 feet by relatively dense, clayey silty sand and
gravel with cobbles and boulders that extended down to maximum depth drilled of 18 feet.
Drilling in the dense coarse granular soils with auger equipment was difficult due to the cobbles
and boulders and drilling refusal was encountered in Borings 1 and 3 in the deposit. The fill was
generally loose, clayey silty sand with gravel.
Laboratory testing performed on samples obtained from the borings included natural moisture
content and density, and gradation analyses. Results of swell-consolidation testing performed on
relatively undisturbed drive samples of the clayey silty sand soils, presented on Figure 4, indicate
low to moderate compressibility under conditions of loading and wetting. Results of analyses
performed on small diameter drive samples (minus 11/inch fraction) of the natural subsoils are
shown on Figures 5 and 6. The laboratory testing is summarized in Table 1.
Groundwater was encountered in Boring 2 at a depth of about 15 feet at the time of drilling. No
groundwater was encountered in Borings 1 and 3. The subsoils were generally moist.
FOUNDATION BEARING CONDITIONS
At assumed excavation depths, the subgrade soils are expected to range from the medium dense,
clayey silty sand soils to the relatively dense, silty clayey sand and gravel with cobble and
boulder soils. These soils possess generally moderate bearing capacity and low to moderate
settlement potential. Spread footings bearing on these soils should be feasible for foundation
support of the building with some risk of differential settlement. The risk of differential
settlement is due to the assumed variable bearing conditions and the more compressible nature of
the clayey silty sand soils. Bearing the footings entirely on the underlying dense coarse granular
soils would provide a relatively low risk of foundation settlement. As an alternative, it may be
feasible to remove and replace a depth (typically 3 feet) of the sand soils in a well compacted
condition in the non-coarse granular soil bearing areas to reduce the risk of differential
settlement. We should review the need for removing and replacing a depth of the sand soils with
structural fill below footing areas at the time of construction.
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Project No. 18-7-252
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Groundwater could be encountered in deeper cut areas at the site depending on when the
excavation is made. The excavation should be dewatered as needed for foundation construction
and permanently to protect below grade construction. Trenches placed outside the footing areas
sloped to gravity outlet should be feasible for shallow drawdown of groundwater for the
construction dewatering, if needed.
DESIGN RECOMMENDATIONS
FOUNDATIONS
Considering the subsurface conditions encountered in the exploratory borings and the nature of
the proposed construction, we recommend the building be founded with spread footings bearing
on the natural granular soil and/or properly placed and compacted structural fill with some risk
of settlement. The structural fill can consist of the on-site sand and gravel soils or suitable
imported granular soils such as road base.
The design and construction criteria presented below should be observed for a spread footing
foundation system.
1) Footings placed on the natural granular soils and/or properly placed and
compacted structural fill should be designed for an allowable bearing pressure of
2,000 psf. Based on experience, we expect settlement of footings designed and
constructed as discussed in this section will be about 1 to 11/2 inches depending on
the foundation loading and subgrade conditions. Structural fill below footing
areas, as needed, or bearing entirely on the natural coarse granular soils will'
reduce the settlement potential.
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 48 inches below exterior grade is typically used in this
area.
4) Continuous foundation walls should be well reinforced top and bottom to span
local anomalies and better withstand the effects of some differential settlement
H-PWUMAR
Project No. 18-7-252
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such as by assuming an unsupported length of at least 14 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) All existing fill, debris, topsoil and any loose or disturbed soils should be
removed and the footing bearing level extended down to the firm natural granular
soils. The exposed soils in footing area should then be moistened as needed and
compacted. If water seepage is encountered, the footing areas should be
dewatered before concrete placement.
6) Structural fill below footing areas should be a suitable granular material approved
by us compacted to at least 98%standard Proctor density at a moisture content
near optimum. Structural fill below footings should extend laterally beyond the
edges of the footings a distance equal to at least 1/2 the depth of fill below the
footings.
6) A representative of the geotechnical engineer should observe all footing
excavations and test structural fill compaction 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 at least 50 pcf for backfill consisting
of the on-site granular soils. Cantilevered retaining structures which are separate from the
residence 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 granular soils. The
backfill should not contain debris, topsoil or oversized (plus 6 inch) rocks.
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
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Project No. 18-7-252
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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 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. Use of a select granular material such as road base and
increasing compaction to at least 98%standard Proctor density could be done to reduce the
backfill settlement.
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. Passive pressure of compacted backfill against the
sides of the footings can be calculated using an equivalent fluid unit weight of 375 pcf. 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 a granular material, such as the on-site
sand and gravel soils, 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. There may be some risk of differential settlement of floor slabs that span from the
more compressible sand to the less compressible sand and gravel with cobble soils. Providing a
depth (typically 11 to 2 feet) of removed and replaced soils in a well compacted condition in the
H-PWUMAR
Project No. 18-7-252
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non-coarse granular soil bearing areas would act to reduce the risk of differential settlement. We
should review the need for removing and replacing a depth of the sand soils with structural fill
below floor slab areas at the time of construction.
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 6-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.
Required fill beneath slabs can consist of the on-site granular soils, excluding debris, topsoil and
oversized (plus 6 inch) rocks, or a suitable imported material such as road base. The fill should
be spread in thin horizontal lifts, adjusted to near optimum moisture content, and compacted to at
least 95% of the maximum standard Proctor density. All fill, topsoil and loose or disturbed soil
should be removed and the subgrade compacted prior to fill placement.
UNDERDRAIN SYSTEM
Groundwater was encountered in one of our borings at a depth of about 15 feet during our field
exploration. It has been our experience in mountainous areas that local perched groundwater can
develop during times of heavy precipitation and groundwater rise during 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 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. If PVC drain pipe is used (which we recommend) the pipe slope can be
H-PKUMAR
Project No. 18-7-252
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reduced to 1/2%. 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, extend to
above any seepage in the adjacent cut face, and be covered by filter fabric such as Mirafi 140N
or 160N.
SITE GRADING
There is a risk of construction-induced slope instability at the site due to the steep slope in the
upper part of the lot and the deeper cuts planned, especially if groundwater seepage would be
encountered. The excavation slopes should be cut back to a stable grade and/or shored. We
recommend cut depths for the basement not exceed one level, about 12 feet unless shored. Soil
nailing is commonly used in the area for shoring and done by design/build contractors with
experience in the area. We can review the excavation and/or shoring plans if desired.
Embankment fills should be limited to about 8 to 10 feet deep, especially in the steeper part of
the sit and 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 debris and topsoil, and compacting to at least 95% of the maximum standard Proctor density.
The fill should be benched horizontally 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. We 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 duplex residence has been completed:
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Project No. 18-7-252
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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 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 filter fabric and about 2 feet of the on-site finer grained soils to
reduce surface water infiltration.
4) Roof downspouts and drains should discharge well beyond the limits of all
backfill.
5) Landscaping which requires regular heavy irrigation should be located at least 5
feet from foundation walls.
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. 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.
H-PWUMAR
Project No. 18-7-252
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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.
Respectfully Submitted,
H-P A KU MAI
Prile/Adf"V
James H. Parsons,E.I.
411,40
Reviewed by: ,to (t01
a s�' 'f. a • V.«I_S ,'
V
d+' i 'x`216
David A. Young, P.1S,Q .,(0»1..1 ckpeq�
JHP/kac 4q#®�p�0 NAL ?,�`
A8aoe.4Q.1%
cc: Martin Manley Architects—John Martin (john@martinmanleyarchitects.com)
Project No. 18-7-252
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4 18-7-252 H-P%KUMAR LOCATION OF EXPLORATORY BORINGS Fig. 1
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BORING 1 BORING 2 BORING 3
EL. 8604' EL. 8684' EL. 8680'
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18-7-252 H-PvKUMAR LOGS OF EXPLORATORY BORINGS Fig. 2
LEGEND
TOPSOIL: ORGANIC CLAYEY SILTY SAND WITH GRAVEL, MOIST, DARK BROWN.
X FILL: MAN—PLACED CLAYEY SILTY SAND WITH GRAVEL, LOOSE, MOIST, RED BROWN TO DARK.
X
/SAND (SC—SM): CLAYEY, SILTY, SCATTERED GRAVEL AND COBBLES, MEDIUM DENSE, MOIST,
/ RED BROWN.
/
/� SAND AND GRAVEL (SC—GC): WITH COBBLES AND PROBABLE BOULDERS, CLAYEY, SILTY,
° / DENSE, MOIST, RED BROWN.
/
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.
9/12 DRIVE SAMPLE BLOW COUNT. INDICATES THAT 9 BLOWS OF A 140—POUND HAMMER
FALLING 30 INCHES WERE REQUIRED TO DRIVE THE CALIFORNIA OR SPT SAMPLER 12 INCHES.
77 DEPTH TO WATER LEVEL ENCOUNTERED AT THE TIME OF DRILLING.
t PRACTICAL AUGER REFUSAL.
NOTES
1. THE EXPLORATORY BORINGS WERE DRILLED ON APRIL 17, 2018 WITH A 4—INCH DIAMETER
CONTINUOUS FLIGHT POWER AUGER.
2. THE LOCATIONS OF THE EXPLORATORY BORINGS WERE MEASURED APPROXIMATELY BY PACING
FROM FEATURES SHOWN ON THE SITE PLAN PROVIDED.
3. THE ELEVATIONS OF THE EXPLORATORY BORINGS WERE OBTAINED BY INTERPOLATION BETWEEN
CONTOURS 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 THE TRANSITIONS MAY BE GRADUAL.
6. GROUNDWATER LEVELS SHOWN ON THE LOGS WERE MEASURED AT THE TIME AND UNDER
CONDITIONS INDICATED. NO GROUNDWATER ENCOUNTERED IN BORINGS 1 AND 3.
7. LABORATORY TEST RESULTS:
WC = WATER CONTENT (%) (ASTM D 2216);
DD = DRY DENSITY (pcf) (ASTM D 2216);
+4 = PERCENTAGE RETAINED ON NO. 4 SIEVE (ASTM D 422);
—200= PERCENTAGE PASSING NO. 200 SIEVE (ASTM D 1140).
18-7-252 H-PkKUMAR LEGEND AND NOTES Fig. 3
SAMPLE OF: Clayey Silty Sand with
Gravel
FROM: Boring 1 CSD 7.5'
WC = 11.7 %, DD = 120 pcf
1
J NO MOVEMENT UPON
J
WETTING
vii 0
—1 •
fi
Z —2
0
I
—3
—4
.1 1.0 APPLIED PRESSURE - KSF 10 100
SAMPLE OF: Clayey Silty Sand with Gravel
FROM: Boring 1 CSD 10'
WC = 11.5 %, DD = 117 pcf
1 I
I
J NO MOVEMENT UPON
J
WETTING
En 0
a —1 •
F,
—2
—3
These test results apply only to the
samples tested.The testing report
shall not be reproduced.except in
$ lull.without the written approval of
i Kumar and Associates.Inc.Swell
Coneolidotian letting performed in
E accordance with ASTM D-4546.
.1 1.0 APPLIED PRESSURE - KSF 10 100
18-7-252 H-P- KUMAR SWELL-CONSOLIDATION TEST RESULTS Fig. 4
HYDROMETER ANALYSIS SIEVE ANALYSIS
TIME READINGS U.S. STANDARD SERIES
CLEAR SQUARE OPENINGS
24 MRS 7 MRS
100 45 MIN 15 MIN GOWN 19141N 4MIN 4MIN — 1MIN #200 0100_ ASO 4. 30 — 16 1. 8 4 3 8" 4" I 1 3" "6" 8'0
90 — _ •
r r / - 10
t I
so I
I 20
70
I I �, 30
I I
50
40
B - _
t S0 I I &
50F. u
a 40 1 I I
+ I 60 W
30 I
70
20
ao
10 . _
go
_
0 1-1-M1 (----1-1-1-1-TTI.T I -(----1-1-1-1-TT-- TTfT\ - MP.- 100
.001 .002 .005 .009 .019 .037 .075 .150 .300 I .600 1.18 12.36 4.75 9.5 19 38.1 76.2 127 200
.425 2.0 152
I DIAMETER OF PARTICLES IN MILLIMETERS
I
CLAY TO SILT SAND GRAVEL
FINE MEDIUM COARSE FINE COARSE COBBLES
GRAVEL 37 % SAND 50 % SILT AND CLAY 13 %
SAMPLE OF: Clayey Silty Sand and Gravel FROM: Boring 2 0 5'
HYDROMETER ANALYSIS SIEVE ANALYSIS
TIME READINGS U.S. STANDARD SERIES I CLEAR SQUARE OPENINGS
24 MRS 7 HRS
100 45 MIN 15 MIN 60MIN 191.1IN 4MIN IMIN 0200 0100 /50.40/30 /16 010 IS /4 3_8" 3 4" 1 1 2" 3" 5"6' 8"o
90 I
I 10
-.- - .. __ I ---
ao
_. I — j 20
70 -
30
-_ I _f___L_
_ -
--
-
- _ -
60 -1
__.-_ __ 1- 40 c
5 -._1 i 50
-_ 60 m
I
I I -
I I L_ 70
20
I I
10
-. I I ._-__-__�._- I _ 90
I ! I--
b 0 I I--f-1T a - INN se ItT TTTI 1 I I I n I 1 1 t IIT 1 El I loo
.001 .002 .005 .009 .019 .037 .075 .150 .300 I .600 1.18 12.36. 4.75 9.5 19 38.1 76.2 127 200
.425Ig 2.0 152 I
12 I DIAMETER OF PARTICLES IN MILLIMETERS
CLAY TO SILT SAND GRAVEL
FINE -1 MEDIUM COARSE FINE COARSE COBBLES
GRAVEL 17 % SAND 60 % SILT AND CLAY 23 %
3
SAMPLE OF: Clayey Sond with Grovel FROM: Boring 2 0 15'
These test results apply only to the
samples which were tasted. The
testing report shall not be reproduced,
except In full, without the written
": approval of Kumar & Associates, Inc.
Sieve analysts testing is performed in
accordance with ASTM D422, ASTM C136
and/or ASTM D1140.
C. 18-7-252 H-PvKUMAR GRADATION TEST RESULTS Fig. 5
HYDROMETER ANALYSIS SIEVE ANALYSIS
TIME READINGS U.S. STANDARD SERIES CLEAR SQUARE OPENINGS
24 HRS 7 HRS
100 45 MIN 15 MIN GOWN 19MIN__ 4MIN MN_ /200 /100 /50J40 4 0 /16 /10/8 4 3/8" 3/4" 1 1 2" " TIT" 8"0
_- _—__ - _ --- _ _-- --. I(( 111
90
to
80
_— —__ I 20
70
30
80 I I
40
P.
50 �— o
€ — w
z
40 L— k
60
30L 70
20 — — 80
10
I 90
0 T I I ry, -I 1 1 1 1 1 1 11 1 11 I l i n I 11 1 I I I I I I I I I I I I 11 I 100
.001 .002 .005 .009 .019 .037 .075 .150 .300 I .600 1.18 12.36 4.75 9.5 19 38.1 76.2 127 200
.425 2.0 152 I
DIAMETER OF PARTICLES IN MILLIMETERS
CLAY TO SILT SAND GRAVEL
FINE MEDIUM COARSE FINE COARSE COBBLES
GRAVEL 19 % SAND 50 % SILT AND CLAY 31 %
SAMPLE OF: Clayey Silty Sand with Gravel FROM: Boring 3 0 10'
c These test results apply only to the
samples which were tested. The
testing report shall not be reproduced,
except In full, without the written
approval of Kumar & Associates, Inc.
Sieve analysis testing Is performed In
accordance with ASTM D422, ASTM C136
,
.1cn
and/or ASTM 01140.
18-7-252 H-PtiKUMAR GRADATION TEST RESULTS Fig. 6
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