HomeMy WebLinkAboutSubsoil StudyI (+rt iäffi fitril*ËtrrrÏiå
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An Employcc Omrcd Compony
5020 County Road 154
Glenwood Springs, CO 81601
phone: (970) 945-7988
fax: (970) 945-8454
email: kaglenwood@kumarusa.com
www.kumarusa.com
Offrce Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
SUBSOIL STUDY
F'OR FOT]NDATION DESIGN
PROPOSED SHOP A¡ID RESIDENCE
TBD PARACIIUTE/RULISON ROAI)
GARFIELD COUNTY, COLORADO
PROJECT NO. 20-7-416
SEPTEMBF,R23,2020
PREPARED FOR:
MIKE PERDUE
P.O. BOX 476
PARACHUTE, COLORADO 81635
@
TABLE OF CONTENTS
PURPOSE AND SCOPE OF STUDY
PROPOSED CONSTRUCTION
SITE CONDITIONS....
FIELD EXPLORATION .......
SI]B SURFACE CONDITIONS
FOLINDATION BEARING CONDITIONS
DESIGN RECOMMENDATIONS .....................
FOI.INDATIONS
FOTINDATION AND RETAINING WALLS
FLOOR SLABS
LINDERDRAIN SYSTEM ..............
SURFACE DRAINAGE
LIMITATIONS
FIGURE 1 - LOCATION OF EXPLORATORY BORINGS
FIGURE 2 - LOGS OF EXPLORATORY BORINGS
FIGURE 3 - LEGEND AND NOTES
FIGURES 4 and 5 - SWELL-CONSOLIDATION TEST RESULTS
FIGURES 6 and 7 - GRADATION TEST RESULTS
TABLE 1- SUMMARY OF LABORATORY TEST RESULTS
1
1
1
2-
,)
3-
3
aJ
4
5
5
6
,,.6 -
Kumar &Associates, Inc, o Project No.20-7-416
PURPOSE AND SCOPE OF STUDY
This report presents the results of a subsoil study for a proposed shop and residence to be located
on ParachutelRulison Road, Garfield County, Colorado. The project site is shown on Figure 1.
The purpose of the study was to develop recommendations for the foundation desi$n. The study
was conducted in accordance with our proposal for geotechnical engineering services to Mike
Perdue dated July 23,2020.
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 analyzedto develop recommendations forfoundation tlpeq depths andallowable--
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
The proposed residence will be a one story wood frame structure over a walkout basement witþ
attached garage. The shop will be a 60 by 100 foot steel frame structure. Ground floors are
assumed be a combination of structural over crawlspace and slab-on-grade for the residence and
slab-on-grade for the shop. Grading for the structures is assumed to be relatively minor with cut
depths between about 2 to l0 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.
SITE CONDITIONS
The subject site was vacant at the time of ow field exploration. The ground surface is sloping
down to the north at grades of between 5 and 15 percent. There is a steep slope of up to 50%
grade to the northwest of the subject site. Vegetation consists of grass and sage brush with
juniper trees near the steep slope to the northwest.
Kumar & Associates, Inc. @ Project No. 20-7-416
a
FIELD EXPLORATION
The field exploration for the project was conducted on July 30, 2020. Four exploratory borings
were drilled and two profile pits were excavated at.the locations shovm on Figure 1 to evaluafe
the subsurface conditions. The borings were advanced with 4 inch diameter continuous flight
Augers powered by a truck-mounted CME-458 drill rig. The borings were logged by a
representative of Kumar & Associates, Inc.
Samples of the subsoils were taken with 1% inch and 2 ineh I.D. spoon samplers. The sampleru
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 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 consist of about Yz foot of topsoil overlying very stiff; low plasticity, sandyclayey silt to
þetween 3 and 7/z feet deep. Underlying the silt, silty clayey sand and gravel was encountered to
the maximum drilled depth of 21 feet. Borings I andT eicoüntered very stiff, high trilasticiÍy, -
sandy clayey silt to befween 12 and 13 feet. Drilling in the dense granular soils with auger
equipment was difficult due to the cobbles and boulders and drilling refusal was encountered in
the deposit in Borings 2 and3.
Laboratory testing performed on samples obtained from the borings included natural moisturç
content, density, Atterberg limits and gradation analyses. Results of swell-consolid-ation te,sli¿g
performed on relatively undisturbed drive samples, presented on Figures 4 and 5, indicate low to
moderate compressibility under conditions existing conditionsand þht l,oadinganúalow--
collapse potential (settlement under constant load) to low swell potential when wetted under
constant light surcharge. Results of gradation analyses performed on small diameter drive
samples (minus lYz-inchfraction) of the coarse granular subsoils are shown on Figures 6 and1.
The laboratory testing is summarizedinTable 1.
No free water was encountered in the borings atthe time of drilling and the subsoils were
slightly moist to moist.
Kumar & Associates, lnc. @ Project No,20-7-416
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FOUNDATION BEARING CONDITIONS
The shallow sandy clayey silt soils encountered at the site possess low bearing capacity and a
variable swellor collapse potential especially when wetted. The exposed soils inÍhe subgrade
should be evaluated for swell potential at the time of excavation. The underlying gravel soils
pç)ssess a moderate bearing cVpacity and a low gettlement potential. 'We anticipate the exposed
subgrade will consist of sandy silt soils. Spread footings placed on the silt soils can be used for
support of the proposed construction can be used with a risk of differential foundation movemeql
and possible distress, especially if the bearing soils become wetted. A lower risk option would
be to extend the bearing level down to the underlying gravel soils either through sub-excavation
to the gravel soils and replacement with imported structural fill or a deep foundation system such
as helical piers or drilled piers.
DESIGN RECOMMENDATIONS
FOI-INDATIONS
Considering the subsurface conditions encountered in the exptoratoryborings anûthe nature of * --
the proposed construction, the buildings can be founded with spread footings bearing on the
natural soils with a risk of foundation movement especially if the bearing soils become wette{.
The design and construction criteria presented below should be observed for a spread footing
foundation system.
1) Footings placed on the undisturbed natural soils should be designed for an
allowable bearing pressure of 1,500 psf. Based on experience, we expect
settlement of footings designed and constructed as discussed in this section will
be up to about 1 inch. A representative of the geotechnical engineer should
observe the exposed soils in the subgrade for swell potential at theiime of
excavation. Sub-excavation of expansive soils and placement of at least 3 feet of
structural fill could be needed to mitigate moistgre sensitive soils.
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 36 inches below exterior grade is fypically used in this
area.
4) Continuous foundation walls should be reinforced top and bottom to span local
anonrralios sueh as þ assumhgrn-unsupporbe#leûgth-ofât.least 12 feet
Foundation walls acting as retaining structures should also be designed to resist
Kumar & Associates, lnc. @ Project No.20-7-416
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lateral earth pressures as discussed in the "Foundation and Retaining Wal.ls"
section of this report.
Topsoil and any loose or disturbed soils should be removed and the footing
bearing level extended down to the natural soils. The exposed soils in footing
area should then be moistened and compacted. If water seepage is encountered,
the footing areas should be dewatered before concrete placement.
A representative of the geotechnical engineer should observe all footing
excavations prior to concrete placement to evaluate bearing conditions.
FOLINDATION AND RETAINING V/ALLS
Foundation walls and retaining structures which arelaterally 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 equivatent fluid unit-weighfof at*east5fpcf fûr backfillconsisting
qf the on-site soils. Cantilevered retaining structures which are separate from the buildings and
can be expected to deflect sufficiently to mobiliZé thê fuIÏ-aetive earth þressure 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 backf,rll consisting of the on-site soils.
4ll foundation and rctaining structures should be designed for appropriate hydrostatic and
surcharge pressures such as adjacent footings, traffrc, 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 90o/o of the maximum
standard Proctor density at a moisture content near optimum. Backfill in pavement and walkway
areas should be compacted to at least 95Yo 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, anúcould resutt in dishess to
facilities constructed on the backfill.
The lateral resistance of foundation or retaining wall footings will bé 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 0.35. Passive pressure of compacted backfill against the
s)
6)
Kumar & Associates, Inc. @ Project No.20-7-416
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sides of the footings can be calculated using an equivalent fluid unit weight of 325 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 compacted to at least 95%ó of the
maximum standard Proctor density at a moisture content near optimum.
FLOOR SLABS
The natural on-site soils, exclusive of topsoil, may be suitable to support lightly loaded slab-on-
grade construction. The exposed underslab soils should be checked for expansion potential at
thstime of construction. If expansive soils are eficonnterefsubexcavation of a few feet of soil
and replacement with imported road base may be needed. To reduce the effects of some
differential movement, floor slabs should be seþarated from all bearing walls and columns with
g¡pansion 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
fevel slabs to facilitate drainage. This material should consist of minus 2-inchaggregate with at
Ieast 50% retained on the No. 4 sieve and less than 2Yo passing the No. 20Û sieve.
All fill materials for support of floor slabs should be compacted to at least 95Yo of maxirmrm
standard Proctor density at a moisture content near optimum. Required fill can consist of
imported granular soils such as3/q-inchroad base devoid of vegetation, topsoil and oversized
rock.
LINDERDRAIN SYSTEM
Although free water was not encountered during our exploration, it has been our experience in
the areathat local perched gtoundwater can develop during times of heavy precipitation or
seasonal runoff. Frozen ground during spring runoff can 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 eaú¡ levsl of -
excavation and at least 1 foot below lowest adjacent finish grade and sloped at a minimum Io/a 1o
a suitable gravity outlet. Free-draining granular material used in the underdrain system should
contain less than 2Yopassingthe No. 200 sieve, less than 50% passing the No. 4 sieve and have a
Kumar & Associates, lnc. @ Project No, 20-7-416
-6-
maximum size of 2 inches. The drain gravel backfill should be at least IYz feet deep. An
impervious membrane such as 20 mil PVC should be placed beneath the drain gravel in a trough
shape and attached to the foundation wall with mastic to prevent wetting of the bearing soils.
SI.IRFACE DRAINAGE
The following drainage precautions should be observed during construction and maintained at all
times after the buildings have been completed:
1) Inundation ofthe foundation excavations andunderslab areas should be avoided
during construction.
2) Exterior backfill should be adjusted to near optimum moisture and compacted to
at least 95o/o of the maximum standard Proctor density in pavement and slab areas
and to at least 90o/o 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 wallbackfillshouldbe
capped with about 2 feet of the on-site soils to reduce surface water infiltration.
4) Roof downspouts anddrains shoul&diseharge-well beyota+thrlimits of all iì
backfill.
5) Landscaping which requires regular heavy irigation should be located at least
10 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 implie{,
The conclusions and recommendations submitted in this report are based upon the data obtained
from the exploratory borings drilled atthe 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 concemed about MOBC, therra professional-in*ris special fieldof
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.
Kumar & Associates, lnc. @ Project No. 20-7-416
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This report has been prepared for the exclusive use by our client for design pu{poses. We are not
responsible for technical interpretations by others of our information. As the project evolves, we
should provjde continued consultation and field services during construction to review and
monitor the implementation of ourrecommendations, and to veriry 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,
Kumar & Associates, Inc.
H. Parsons, E.I.
Reviewed by:
Daniel E. Hardin,
JHPlkac
Kumar & Assoeiates, lnc. @ Project No.20-7-416
t
O BORING 2
o PROPOSED RESIDENCE
BORING 1
PP-1 I r,,-2
BORING ¡l
o
o
BORING 3
PROPOSED
SHOP
;._
NOT TO SCALE
LOCATION OF EXPLORATORY
BORINGS AND PITS Fig. 120-7 -41 6 Kumar & Associates
BORING 1
EL. 60.9'
BORING 2
EL. 53.4'
BORING 5
EL. 94.2'
BORING 4
EL. 91 .8'
01s/12
2e/12
WC=4.2
DD=94
-200=88
23/ 12
WC=5.8
ÐD=122
-200=89
5 5
26/12
WC=4.3
DD=97
1s/12
\NC=14.7
DD=68
-2OO=46
21/12
WC=6.4
DD=1 07
1e/12
WC=4.8
DD= 1 05
t-
l¡JLIl¡-
I-FfL
LJô
10 10
FLJt¡ltL
I
70/12
WC=.l4.5
DD=98
57 /12
WC=5.4
+4=23
-2OO=34
LL=26
PI=E
36/6, 5s/6
WC=7.2
-200=22
LL= 29
Pl=2
5a/ 1
Õ
15 27/6,3s/6 1550/3 50/1
2A 20
50/2
25 25
PROFILE PIT 1 PROFILE PIT 1
0 0
l-t¡l
t¡Jti-
I-t-.-fLl¡lo
5
-l wc=¡.1
_l cn¡vrt=t
SAND=38
SILT=50
CLAY=11
5
F
L¡J
l¡JlL
ITF(L
tJô
l010
Fig. 220-7 -41 6 Kumar & Associates LOGS OF EXPLORATORY
BORINGS AND PITS
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LEGEND
TOPSOIL; SILT, SAND, CLAY, ORGANIC MATTER, SOME GRAVEL AND COBBLES,
MEDIUM DENSE, DRY TO SLIGHTLY MOIST, LIGHT BROWN.
SILT (ML); SLIGHTLY SANDY TO SANDY, MEDIUM DENSE, SLIGHTLY MOIST, TAN, SLIGHTLY
CALCAREOUS.
S|LT (ML); SLIGHTLY SANDY To SANDY, occASloNAL MEDIUM GRAVEL, MEDIUM DENSE To
VERY DENSE, SLIGHTLY MOIST, WHITE CALICHE.
GRAVEL (CC); CI-¡YEY, SANDY GRAVEL AND SAND ANGULAR, VERY DENSE, SLIGHTLY
MOISÏ, TAN.
GRAVEL (CU); Str-tV, SANDY TO VERY SANDY GRAVEL ANGULAR WITH SOME BASALT
PIECES, VERY DENSE, SLIGHTLY MOIST, TAN.
DRIVE SAMPLE, 2_INCH I.D. CALIFORNIA LINER SAMPLE.
DRTVE SAMPLE, 1 3/9-|NCH l.D. SPLIT SPOON STAI,IDARD PENETRATION TEST.
,o/1, DRTVE SAMPLE BLOW COUNT. INDICATES THAT 29 BLOWS OF A 14o-POUND HAMMER
FALLING 30 INCHES WERE REQUIRED TO DRIVE THE SAMPLER 12 INCHES.
f enacrrcAl AUGER REFUsAL.
NOTES
THE EXPLORATORY BORINGS WERE DRILLED ON JULY 30, 2O2O WIÏH A 4_INCH-DIAMETER
CONTINUOUS-FLIGHT POWER AUGER.
2. THE EXPLORATORY BORINGS WERE LOCAÏED BY THE CLIENT.
5. THE ELEVATIONS OF THE EXPLORATORY BORINGS WERE MEASURED BY INSTRUMENT LEVEL AND
REFER TO THE GROUNÐ SURFACE AT THE WESTERN MOST ENTRY GATE POST AS 1 OO'
ASSUMED.
4. THE EXPLORATORY BORING LOCATIONS AND ELEVATIONS SHOULD BE CONSIDERED ACCURATE
ONLY TO THE DEGREE IMPLIED BY THE MEIHOD USEÛ.
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 WAS NOT ENCOUNTERED IN THE BORINGS AT THE TIME OF DRILLING
7. LABORATORY TEST RESULTS:
WC = WATER CONTENT (%) (ASTM Ð2216);
DD = DRY DENSITY (pcf) (ASTM D2216);
+4 = PERCENTAGE RETAINED ON NO. 4 SIEVE (ASTU OOSIS);
-200= PERCENTAGE PASSING NO. 200 SIEVE (ASTM Dl140);
LL = LTQUTD LrMrT (ASTM Da318);
Pl = PLASTICITY INDEX (ASTM 0a518);
GRAVEL = PERCENT RETAINED ON NO. 10 SIEVE;
SAND = PERCENT PASSING NO. 1 0 SIEVE AND RETAINED oN No. 325 SIEVE;
SILT = PERCENT PASSING NO. 325 SIEVE TO PARTICLE SIZE .002MM;
CLAY = PERCENT SMALLER THAN PARTICLE SIZE .002MM'.
i
1
LEGEND AND NOTES Fig. 320-7 -41 6 Kumar & Associates
I
SAMPLE OF: Sllghtly Sondy Silt
FROM:Boringl@5'
WC = 4.ı %, DD = 97 pcf
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¡
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EXPANSION UNDER CONSTANT
PRESSURE UPON WETTING
JJl¡l
=ln
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-1
-2
-3
-4
1.0 - KSF t0
JJl¡J
=tt',
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z.o
F
Õ
JoÎnzo()
2
1
0
-1
-2
-3
PRESSURE - KSF t0 100
SAMPLE OF: Slightly Sondy Silt with Coliche
FROM: Boring 1 @ 10'
WC = 14.5 %, DD = 98 pcf
'i
Ii
IIiì
th.
ThGtët d.
th€
lf,
- -: i : -
I
EXPANSION UNDER CONSTANT
!l
ir
iì:
t)ii:iì.
i PRESSURE UPON WETTING
20-7 -416 Kumar & Associates SWELL-CONSOLIDATION TEST RESULTS Fig. 4
{
SAMPLE OF: Slightly Sondy to Sondy Silt
FROM:BoringS@5'
WC = 6.4 %, DD = 107 pcf
I
I
I
I
il
I
l
I
,l
1l
I
1
EXPANSION UNDER CONSTANT
PRESSURE UPON WETTING
{
JJIJ
=UI
I
z.o¡-
o
=o
U1z.oo
1
0
-1
2
1.0 10 100
àq
-J-JL¡l
=(n
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z.o
F-
ô
Jotnz.oO
1
0
-1
-2
-3
ÁPPLIED PRESSURE - KSF f0
SAMPLE OF: Slightly Sondy Silt
FROM:Boring4@5'
WC = 4.8 %, DD = 103 pcfiil1,,
rlìll
ilt
l
I
ADDITIONAL COMPRESSION
UNDER CONSTANT PRESSURE
DUE TO WETTING
I -t -
rlr
i :-* t:ll
:lt;,i
il
!
i
üø td @Ra opply oDly b fb
smplæ t.Bt d. lh. t6t¡ng Gpod
lhqll nol b! roprdrcod, ê¡copt ln
lull, without tho wlttsn eprovol of
Kuñor ond Ás@¡otlq læ, Ss6ll
conÈol¡dotìoñ t.5t¡ng p€ffom.d ¡n
æcôrddR. {¡th Æil 0-4544.
20-7 -416 Kumar & Associates SWELL-CONSOLIDATION TEST RESULTS Fig. 5
û
t00
90
ao
70
60
50
40
30
20
to
o
HYDROMETER ANALYSIS SIEVE ANALYSIS
Ttt¡€ REAOTNGS
24 HRS 7 HRS
U.S. STANDARO SERIES CI.EAR SQUARE OPENI¡GS
a/*, 3f^' t | /r" 3'
I
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Iijrl
I lll rì
L
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l:,",ffi ',1 1"'1"1 lil
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tttlrlIrl
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20
30
40
50
60
70
80
90
too
¡
I
.o37 t9 5a,t.125'2.O
ILLIMETERSDIAMETERFINM
CLAY TO SILT COBBLES
GRAVEL 23 % SAND
LIQUID LIMIT 26
SAMPLE OF: Cloyey Sond wilh Grovel
43%
PLASTICITY INDEX
SILT AND CLAY 34 %
I
FROM:Bor¡ng2Ol0'
fhâlc l6sl rosulls opply only lo lhâ
sdñDl€s whlch wero lesled. fhe
tesliirg report $holl not ba reproduced,
ôxcopt ln full, wllhoul lha wrlll€n
opprovol of Kumor & Assoclolos, lnc.
Si€vg qnolysls t.sllng is pgrlormod lñqccordoncrvllh ASTI - D89'l 5; ASTII }792E;
ASTM Cl56 qnd/or ASTM 01140.
GRAVELSAND
MEDTUM lco¡nsE FIN E COARSEFINE
20-7 -41 6 Kumar & Associates GRADATION TEST RESULTS Fig.6
SIEVE ANALYSISHYDROMETER ANALYSIS
NGS SERIES
24HR 7HR
045 100
10
g0
20 BO
30 70
ô
L¡lz
F
LrlE
Fz
LilOtL¡
o_
40 60 z
Ø
U)
o_
Fz
L¡lOu
LJ
o
50 50
60 40
70 30
80 20
90 10
100 106 .025 .500 1.00 2,00 4.75 9.5 19,0 37.5 76.2 152 203.001 .002 .045
DIAMETER OF PARTICLES IN MILLIMETERS
CLAY COBBLÊS
GRAVEL 1 %SAND 38 %SILT 50 %CLAY 11 %
USDA SOIL TYPE: Very Sandy Slightly Loam FROM: PlTl @3'-4.5'
/
I
SAND
LAFGEFINEMEDIU[J{strf
lig. 7USDA GRADATION TEST RISULTSKumar & Associates20-7-416
Ktrlfumal & Associates, lnc.'Geotechnical and Materials Engineersand Environmental ScientistsTABLE 1SUMMARY OF LABORATORY TEST RESULTSProject No. 20-7-4161 ol2Silty Sandy GravelSlightly Sandy SiltSOIL TYPESlightly Sandy SiltSlightly Sandy SiltSlightly Sandy Silt \MithCalictreSand and SiltClayey Sand with GravelSlightly Sandy to SandySiltSlightly Sandy to SandysiltfosfìUNCONFINEDCOMPRESSIVESTRENGTH2lololPLASTICINDEX829ATTERBERG LIMITSlo/.1LIQUID LIMIT2646348922PERCENTPASSING NO.200 srEVE88l:/"1SAND43GRADATION(%)GRAVEL23r0710394979868t22NATURALDRYDENSITYlocflt4.514.75.45.86.47.24.8IololNATURALMOISTURECONTENT4.24.3015102y,50I5{fttDEPTH2Yz5Boring 3Boring 4SAMPLE LOCATIONBoring/PitBoring 1Boring 2
l(+ i,ff*fi#ffffifliifü**TABLE 1SUMMARY OF LABORATORY TEST RESULTSProject No. 20.74162oÍ2SOIL TYPEvery11SlightlytcráY(%)SILT$l50SAND(%)38USDA SOIL TEXTUREGRAVELl%lV"lSILT&CLAYSAND$t1(%)GRAVELNATURALDRYDENSIÏY(pcr)NATURALMOISTURECONTENT(%)3.1PITDEPTH(ft)3-4y,ProfilePitl r