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GTLITHOMPSON
YEARS
FOUNÐED IN 197I
CTL I THOMPSON
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GEOTECHNICAL ENGINEERING INVESTIGATION
HOWARD RESIDENCE ADDITION
5749 COUNTY ROAD 309
GARFIELD COUNTY, COLORADO
Prepared For:
LARRY HOWARD
5749 County Road 309
Parachute, CO 81635
Project No. GS06567.000-1 20
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June 10,2021
TABLE OF CONTENTS
scoPE......
SUMMARY OF CONCLUSIONS ........
SITE CONDITIONS
PROPOSED CONSTRUCTION .........
SUBSURFACE CONDITIONS.... ......
EARTHWORK..............
Subexcavation and Structural Fill....
Foundation Wall Backfi11..................
FOUNDAT|ON ................
SLAB.ON.GRADE CONSTRUCTION
CRAWL SPACE CONSTRUCTION,...
FOUNDATION WALLS
SUBSURFACE DRAINAGE.....,....,.....
SURFACE DRAINAGE
CONCRETE
CONSTRUCTION OBSERVATIONS .
GEOTECHNICAL RISK
LtMtTATtONS .........., . .
FIGURE 1-VICINIryMAP
FIGURE 2 -AERIAL PHOTOGRAPH
FIGURE 3 _ SUMMARY LOG OF EXPLORATORY PITS
FIGURE 4 - SWELL-CONSOLDATION TEST RESULTS
FIGURES 5 AND 6 _ FOUNDATION WALL DRAIN CONCEPTS
TABLE I - SUMMARY OF LABORATORY TESTING
LARRY HOWARD
HOWARD RESIDENCE ADDITION
PROJECT NO. cS06567.000-120
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'....,.'' 1
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SCOPE
CTL I Thompson, lnc. has completed a geotechnical engineering investi-
gation for the addition to the Howard Residence at 5749 County Road 309 in
Garfield County, Colorado. We conducted this investigation to evaluate subsur-
face conditions at the síte and provide geotechnical engineering recommenda-
tions for the planned construction. The scope of our investigation was set forth in
our Proposal No. GS 21-0173. Our report was prepared from data developed
from our field exploration, laboratory testing, engineering analysis, and our expe-
rience wíth similar conditions. This report includes a description of the subsurface
conditions observed in our exploratory pits and presents geotechnical engineer-
ing recommendations for design and construction of the foundation, floor system,
below-grade walls and details influenced by the subsoils. A summary of our con-
clusions is below,
SUMMARY OF CONCLUSIONS
ffi
subsoils encountered in our exploratory pits consisted of about s to 6
inches of sandy clay "topsoil" underlain by sandy clay with gravel, cob-
bles, and boulders. Boulders encountered in our exploratory pits made
excavation deeper than I feet not practical. Groundwater was not
found in our exploratory pits.
The sandy clay soil at the site has potentíal for significant consolidatÍon
settlement when wetted under building loads. we judge that a footing
foundation is appropriate for the addition, provided thé soils are subãx-
cavated to a depth of at least 2 feet below footings and replaced as
densely-compacted, structural fill. we recommend provision of a con-
struction joint between the addition and existing building, which can ac-
commodate some differential movement.
A slab-on-grade floor is proposed in basement and garage areas of the
addition. To enhance potentialfloor srab performanCe, we recommend
subexcavation of the soils below floor slabs to a depth of at least z feet
and replacement with densely-compacted, structural fill.
1
2
3
LARRY HOWARD
HOWARD RESIDENCE ADDITION
PROJECT NO. cso6567.000-120
1
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4 A foundation wall drain should be constructed around the perimeter of
basement and crawl space areas berow the addition. site grading
should be designed and constructed to rapidly convey surfãce wáter
away from the residence.
SITE CONDITIONS
The Howard Residence is at 5749 County Road 309 in Garfield County,
Colorado. A vicinity map with the location of the site is included as Figure 1. The
property is northeast of the intersection of County Road 323 and County Road
309' The existing residence on the property is a one-story, wood-frame building.
An aerial photograph of the site is shown on Figure 2. The main level floor in the
residence is structurally-supported with a crawl space below. Ground surface at
the site is generally slopes at grades less than 5 percent down to the northwest.
The addition is proposed at the north side of the residence. The area of the
planned addition is vegetated with grass and several mature fruit trees. A photo-
graph of the site at the time of our investigation ís below.
, åãftå .,r¡¿¡*#;1 udgP*t"r*t
Looking northwest across addition area towards Tp-2
LARRY HOWARD
HOWARD RESIDENCE ADDITION
PROJECT NO. cS06567.000-t20
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PROPOSED CONSTRUCTION
Architectural plans for the addition were not finalized at the time of our ge-
otechnical engineering investigation. We reviewed schematic plans for the addi-
tion drawn by D. Becker (dated February 2021). The addition is planned as a one
or two-level, wood-frame structure constructed adjacent to the north and east
side of the existing residence. A partial walk-out basement with a slab-on-grade
floor may be constructed below parts of the addition. New garage space with a
slab-on-grade floor is planned adjacent to the east side of the existing residence.
We anticipate foundation loads along perimeter walls between 1,000 and 2,000
pounds per linear feet with maxímum column loads of less than 50 kips. Maxi-
mum foundation excavation depths of 8 to 10 feet are anticipated to construct the
basement. We should be provided with architectural ptans, as they are further
developed, so we can provide geotechnical/geo-structural engineering input.
SUBSURFACE CONDITIONS
Subsurface conditions at the site were investigated by observing the exca-
vation of two exploratory pits (TP-1 and TP-2) near the planned addition footprint.
The pits were excavated with a trackhoe at the approximate location shown on
Figure 2. Exploratory excavation operations were directed by our engineer, who
logged subsurface conditions encountered and obtained samples of the soils.
Graphic logs of the soils found in our exploratory pits are shown on Figure 3.
Subsoils encountered in our exploratory pits consisted of about b to 6
inches of sandy clay "topsoil" underlain by sandy clay with gravel, cobbles, and
boulders. Boulders encountered in our exploratory pits made excavation deeper
than 8 feet not practical. Groundwater was not found in our exploratory pits at the
LARRY HOWARD
HOWARD RESIDENCE ADDITION
PROJECT NO. GS05s67.000-t20
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time of excavation. PVC pipe was installed in our pits, prior to backfilling, to facili-
tate subsequent checks of ground water. A photograph of conditions exposed in
our exploratory pits is below.
Conditions exposed in Tp-2
Samples of the soils obtained in the field were returned to our laboratory
where typical samples were selected for testing. One sample of the sandy clay
selected for one-dimensíonal, swell-consolidation testing exhibited 0.6 percent
consolidation when wetted under an applied pressure of 1,000 psf. Engineering
index testing on two samples indicated the sandy clay soil is moderately plastic
with liquid limits of 39 and 44 percent and plasticity indices of 1B and 21 percent.
The samples contained s1 and 5s percent silt and clay (passing the No. 200
sieve). Swell-consolidation test results are shown on Figure 4. Laboratory test re-
sults are summarized on Table l.
LARRY HOWARD
HOWARD RESIDENCE ADDITION
PROJEcT NO. G506s67.000"120
4
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EARTHWORK
Based on our subsurface investigation, excavation for the addition can be
accomplished with conventional, heavy-duty excavation equipment. Some me-
dium-size boulders should be anticipated. Sídes of excavations must be sloped
or braced to meet local, state and federal safety regulations. The soils at the site
will likely classify as Type B or Type C, based on OSHA standards governing ex-
cavations. Temporary slopes deeper than 5 feet and above groundwater should
be no steeper than I to 1 (horizontal to vertical) in Type B soils and 1.5 to 1 in
Type C soils. Contractors are responsible for site safety and providing and main-
taining safe and stable excavations. Contractors should identify the soils encoun-
tered in excavations and ensure that OSHA standards are met. Care should be
taken to avoid undermining the existing buílding components.
Our exploratory pits did not penetrate groundwater at the time of excava-
tion. We do not expect excavation for the addition will penetrate a free groundwa-
ter table. Excavations should be sloped to gravity discharges or be directed to
temporary sumps where water from snowmelt and precipitation can be removed
by pumping.
Subexcavation and Structural Fill
The sandy clay soil at the site has potential for significant consolidation
settlement when wetted under building loads. Settlement of the addition founda-
tion would be differential with respect to the existing building. We judge that a
footing foundation and slab-on-grade floors are appropriate for the addition, pro-
vided the soils are subexcavated to a depth of at least 2 feet below planned foot-
ings and slabs to reduce potential risk of consolidation settlement. A more uni-
LARRY HOWARD
HOWARD RESIDENCE ADDITION
PROJECT NO. cS06s67.000-120
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form structural fill would result by subexcavating below the entire addition foot-
print. The subexcavation process should extend at least 1 foot beyond the perim-
eter of the addition footprint.
The excavated soils can be reused as structuralfill, provided they are free
of rocks larger than 4 inches, organics, and debris. Structural fill should be
placed in loose lifts of B inches thick or less, moisture-conditioned to within 2 per-
cent of optimum moisture content, and compacted to at least g8 percent of stand-
ard Proctor (ASTM D 698) maximum dry density. Moisture content and density of
structural fill should be checked by a representative of our firm during placement.
observation of the placement and compaction process is necessary.
Foundation Wall Backfill
Proper placement and compaction of foundation wall backfill is important
to reduce infiltration of surface water and settlement of backfill settlement from
consolidation of backfill soils. This is especially important for backfill areas that
will support exterior concrete flatwork. The excavated soils free of rocks larger
than 4 inches in diameter, organics, and debris can be reused as backfill adja-
cent to foundation wall exteriors.
Backfill should be placed in loose lifts of approximately 10 inches thick or
less, moisture-conditioned to within 2 percent of optimum moisture content, and
compacted to at least g5 percent of standard Proctor (ASTM D 698) maximum
dry density, Moisture content and density of the backfill should be checked during
placement by a representative of our firm. Observation of the compaction proce-
dure is necessary.
LARRY HOWARD
HOWARD RESIDENCE ADDITION
PROJECT NO. GS06567,000-t20
6
FOUNDATION
The sandy clay soil at the site has potential for significant consolidation
settlement when wetted under building loads. Settlement of the addition founda-
tion would be differential with respect to the existing building. We judge that a
footing foundation is appropriate for the addition, provided the soits are subexca-
vated to a depth of at least 2 feet below planned footings to reduce potential risk
of consolidation settlement. The excavated soils should be replaced with
densely-compacted, structural fill in accordance with the Subexcavation and
Structural Fill section.
We expect maximum total settlement of less than 1 inch for the addition
footings supported on densely-compacted, structural fill. This setflement will be
differential with respect to the existing building. We recommend provision of a
slip joint between the addition and existing building, which can accommodate
some d ifferential movement.
Recommended design and construction criteria for footing foundations are
below. These criteria were developed based on our analysis of field and labora-
tory data, as well as our engineering experience.
1 The addition can be constructed on a footing foundation that is sup-
ported by an at least 2-foot thickness of densely-compacted, struc-
tural fill. The structuralfill should be ín accordance wíth the subex-
cavation and Structural Fill section.
2
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Footings on the structural fill can be sized using a maximum net al-
lowable bearing pressure of 3,000 psf. The weight of backfill soil
above the footings can be neglected for bearing pressure calcula-
tion.
continuous wall footings should have a minimum width of at least
16 inches. Foundations for isolated corumns should have minimum
dimensions of 24 inches by 24 inches. Larger sizes may be re-
quired, depending upon foundation loads.
3.
LARRY HOWARD
HOWARD RESIDENCE ADDITION
PROJECT NO. GS06567.000-120
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4 Grade beams and foundation wails should be well-reinforced to
span undisclosed loose or soft soíl pockets. we recommend rein-
forcement sufficient to span an unsupported distance of at least 12
feet.
5 The soils under exterior footings should be protected from freezing.we recommend the bottom of footings be constructed at a depth ıf
at least 36 inches below finished exterior grades, The Garfield
county building department should be consulted regarding required
frost protection depth.
SLAB.ON.G RADE CONSTRUCTION
A slab-on-grade floor is planned in basement and garage areas of the addi-
tion' Exterior concrete flatwork is likely to be constructed adjacent to the building.
To enhance potential floor slab performance, we recommend subexcavation of
the soils below floor slabs to a depth of at least 2 feetand replacement with
densely-compacted, structural fill. The structural fill should be in accordance with
recommendations in the Subexcavation and Structural Fill section.
Based on our analysis of field and laboratory data, as well as our engineer-
ing experience, we recommend the following precautions for slab-on-grade con-
struction at this site.
slabs should be separated from exterior walls and interior bearing
members with slip joints that allow free vertical movement of the
slabs.
The use of underslab plumbing should be minimized. underslab
plumbing should be pressure tested for leaks before the slabs are
constructed. Plumbing and utilities which pass through slabs should
be isolated from the slabs with sleeves and provided with flexible
couplings to slab supported appliances.
Exterior concrete flatwork shourd be isolated from the building,
These slabs should be well-reinforced to function as indepenãent
LARRY HOWARD
HOWARD RESIDENCE ADD¡lION
PROJECT NO. GS06567.000-120
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units. Movements of these slabs should not be transmitted to the
building.
Frequent controljoints should be provided, in accordance with
American concrete lnstitute (Acl) recommendations, to reduce
problems associated with shrinkage and curling.
The lnternational Building code (lBc) may require a vapor retarder
be placed between the base course or subgrade soils and the con-
crete slab-on-grade floors. The merits of installation of a vapor re-
tarder below floor slabs depend on the sensitivity of floor coverings
and building to moisture, A properly installed vapor retarder (10 mil
minimum) is more beneficial below concrete slab-on-grade floors
where floor coverings will be sensitive to moisture.
CRAWL SPACE CONSTRUCTION
Crawl spaces are contemplated below the main level floor in parts of the
addition. Where structurally-supported floors are installed over a crawlspace, the
required air space depends on the materials used to construct the floor. Building
codes normally require a clear space of at least 18 inches between exposed
earth and untreated wood floor components of the structural floor. For non-or-
ganic systems, we recommend a minimum clear space of 12 inches.
Utility connections, including water, gas, air duct, and exhaust stack con-
nections to appliances on structural floors should be capable of absorbing some
deflection of the floor. Plumbing that passes through the floor should ideally be
hung from the underside of the structural floor and not laid on the bottom of the
excavation. lt is prudent to maintain the minimum clear space below all plumbing
lines.
Control of humidity in crawl spaces is important for indoor air quality and
performance of wood floor systems. We believe the best current practices to con-
trol humidity involve the use of a vapor retarder or vapor barrier (10 mil minimum)
LARRY HOWARD
HOWARD RESIDENCE ADDITION
PROJECT NO. cS06567.000-120
4
5
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placed on the soils below accessible subfloor areas, The vapor retarder/barrier
should be sealed at joints and attached to concrete foundation elements. lt may
be appropriate to install ventilation systems that are controlled by humidistat.
FOUNDATION WALLS
Foundation walls whích extend below-grade should be designed for lateral
earth pressures where backfill is not present to about the same extent on both
sides of the wall, such as in basements and crawl spaces. Many factors affect
the values of the design lateral earth pressure. These factors include, but are not
limited to, the type, compaction, slope, and drainage of the backfill, and the rigid-
ity of the wall against rotation and deflection.
For a very rigíd wall where negligible or very little deflection will occur, an
"at-rest" lateral earth pressure should be used in design. For walls that can de-
flect or rotate 0.5 to 1 percent of wall height (depending upon the backfill types),
design for a lower "active" lateral earth pressure may be appropriate. Our experi-
ence indicates typical below-grade walls in residences deflect or rotate slighly
under normal design loads, and that this deflection results ín satisfactory wall
performance. Thus, the earth pressures on the walls will likely be between the
"active" and "at-rest" conditions.
For backfill soils conforming with recommendations in the Foundation Wall
Backfill section that are not saturated, we recommend design of below-grade
walls at this site using an equivalent fluid density of at least 45 pcf. This value as-
sumes deflection; some minor cracking of walls may occur. lf very lit¡e wall de-
flection is desired, a higher design value approaching the "at-rest" condition using
an equivalent fluid pressure of 60 pcf may be appropriate.
LARRY HOWARD
HOWARD RESIDENCE ADDITION
PROJECT NO. cS06s67.000.120
10
SUBSURFACE DRAINAGE
Water from precipitation and surface irrigation frequently flows through rel-
atively permeable backfíll placed adjacent to a building, and collects on the sur-
face of less permeable soils at foundation elevation. This process can cause wet
or moist conditions after construction. To reduce the likelihood water pressure
will develop outside foundation walls and the risk of wetting in below-grade ar-
eas, we recommend provision of a foundation wall drain around the perimeter of
the additoina. The drain should consist of a 4-inch diameter, slotted pipe encased
in free-draining gravel. The drain should discharge via a positive gravity ou¡et or
lead to a sump where water can be removed by pumping. The discharge point of
the drain should not be direct water toward the existing crawl space areas below
the building. Foundation wall drain concepts are shown on Figures 5 and 6.
SURFACE DRAINAGE
Surface drainage is critical to the performance of foundations, floor slabs
and, concrete flatwork. Site drainage should be designed to rapidly convey sur-
face water away from the residence. Proper surface drainage and irrigation prac-
tices can help control the amount of surface water that penetrates to foundation
levels and contributes to settlement or heave of soils that support foundations,
slabs, and other structures. Positive drainage away from the foundation and
avoidance of irrigation near the foundation also help to avoid excessive wetting of
backfill soils, which can lead to increased backfill settlement and possibly to
higher lateral earth pressures, due to increased weight and reduced strength of
the backfill. We recommend the following precautions.
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The ground surface surrounding the exterior of the residence
should be sloped to drain away from the buílding in all directions.we recommend a minimum constructed slope of at least 12 inches
in the first 10 feet (10 percent) in landscaped areas around the resi-
dence.
1
LARRY HOWARD
HOWARD RESIDENCE ADDITION
PROJECT NO. cS06567.000-120
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Backfill around the foundation walls should be moisture-treated and
compacted pursuant to recommendations in the Foundation wall
Backfill section
we recommend the addition and existing building be provided with
roof gutters and downspouts. The downspouts should discharge
well beyond the limits of all backfill, sprash blocks and/or exteñ-
sions should be provided at all downspouts so water discharges
onto the ground beyond the backfill. we generalry recommend
against burial of downspout discharge.
lrrigation should be limited to the minimum amount sufficient to
maintain vegetation; application of more water will increase likelí-
hood of slab and foundation movements. prants placed close to
foundation walls should be limited to those with low moisture re-
quirements. lrrigated grass should not be rocated within 5 feet of
the foundation. sprinklers should not discharge within 5 feet of
foundations. Plastic sheeting shourd not be placed beneath land-
scaped areas adjacent to foundation walls or grade beams. Geo-
textile fabric will inhibit weed growth yet still allow natural evapora-
tion to occur.
CONCRETE
Concrete ín contact with soil can be subject to sulfate attack. Our experi-
ence in the area of the site indicates the soils contain low levels of water-soluble
sulfates. ACI 332-08, "Code Requirements for Residential Concrete", indicates
that any type of cement can be used for concrete in contact with the subsoils that
have low levels of sulfate concentration
ln our experience, superficial damage may occur to the exposed surfaces
of highly-permeable concrete, even though sulfate levels are relatively low. To
control this risk and to resist freeze-thaw deterioration, the water-to-cementitious
materials ratio should not exceed 0.50 for concrete in contact with soils that are
likely to stay moist due to surface drainage or high-water tables. Concrete should
have a total air content of 6 percent +t- 1.5 percent. We recommend all founda-
tion walls and grade beams in contact with the subsoils be damp-proofed.
LARRY HOWARD
HowARD REsTDENcE ADDrroN 12
PROJECT NO. cS06567.000-{20
2
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CONSTRUCTION OBSERVATIONS
We recommend that CTL I Thompson, lnc. be retained to provide con-
struction observation and materials testing services for the project. This would al-
low us the opportunity to verify whether soil conditions are consistent with those
found during this investigation. lf others perform these observations, they must
accept responsibility to judge whether the recommendations in this report remain
appropriate. lt is also beneficialto projects, from economic and practical stand-
points, when there is continuity between engineering consultation and the con-
struction on materials testing phases.
GEOTECHNICAL RISK
The concept of risk is an important aspect of any geotechnical evaluation.
The primary reason for this is that the analytical methods used to develop ge-
otechnical recommendations do not comprise an exact science. The analytical
tools whích geotechnical engineers use are generally empirical and must be tem-
pered by engineering judgment and experience. Therefore, the solutions or rec-
ommendations presented in any geotechnical evaluation should not be consid-
ered risk-free and are not a guarantee that the interaction between the soils and
that the proposed structure will lead'to performance as desired or intended. The
engineering recommendations in the preceding sections constitute our estimate
of those measures necessary to help the buirding perform satisfactorily.
This report has been prepared for the exclusive use of the client for the
purpose of providing geotechnical design and construction criteria for the pro-
posed project. The information, conclusions, and recommendations presented
herein are based upon consideration of many factors including, but not limited to,
the type of structures proposed, the geologic setting, and the subsurface condi-
LARRY HOWARD
HOWARD RESIDENCE ADDITION
PROJECT NO. cso6567.000-120
l3
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tions encountered. The conclusions and recommendations contained in the re-
port are not valid for use by others. Standards of practice continuously change in
the area of geotechnical engineering. lf the proposed addition is not constructed
within three years, we should be contacted to determine if we should update this
report.
LIMITATIONS
Our exploratory pits provide a reasonably accurate picture of subsurface
conditions below the site. Variations in the subsurface conditions not indicated by
the pits will occur. We should be provided with architectural plans, as they are
further developed, so we can provide geotechnical/geo-structural engineering in-
put.
This investigation was conducted in a manner consistent with that level of
care and skill ordinarily exercised by geotechnical engineers currently practicing
under similar conditions ín the locality of this project. No warranty, express or im-
plied, is made. lf we can be of further service in discussing the contents of this
report, please call.
cTL I THOMPSON, tNC Reviewed by
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Ryan R. Barbone, P.E
Project Engineer
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LARRY HOWARD
HOWARD RESIDENCE ADDITION
PROJECT NO. GS06567.000-120
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0 1000 2000 NOTE:
SCÄ[E: 1- - 2000'
Larry Howard
Ho¡¡rd Resklenca
PROJECT NO. GSO6567.000-1 20
SATELLITE IMAGE FROM GOOGLE EARTH
(DATED JUNE 17, 2oi6)
Vicinity
Map
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County Rood 509
Howord Residence
Fls. 1
LEGEND:
TP_1 APPROXIMATE LOCATION OFT EXPLoRAToRY PIT
APPROXIMATE LOCATION OF
PROPERTY BOUNDARY
NOTE:
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SCALE: 1'= 50'
50 SATELLITE IMAGE FROM GOOGLE ËARTH
(DATED JUNE '17, 2016)
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Aerial
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Larry Howard
Hourard Ro¡ldonco
PROJECT NO. GSO6567.OOO-1 20
TP-1 'rP-2
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Photograph Flg. 2
TP-1
10
15
LARRY HOWARD
HOWARD RESIDENCE
CTLIT PROJECT NO. GS06567.000-120
TP-2
0 LEGEND:
55
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TOPSOIL, CLAY, SANDY, MOIST. BROWN,
DARK BROWN.
CLAY, SANDY, GRAVEL, COBBLES,
BOULDERS, MOIST, SOFT TO MEDIUM
STIFF, BROWN,
INDICATES BULK SAMPLE FROM EXCAVATED SOILS.
INDICATES HAND DRIVE SAMPLE.
DEPTH AT WHICH BOULDERS MADE DEEPER
EXCAVATION NOT PRACTICAL.
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10
15 NOTES:
T
EXPLORATORY PITS WERE EXCAVATED WITH A
TRACKHOE ON APRIL 28,2021. PITS WERE
BACKFILLED IMMEDIATELY AFTER EXPLORATORY
EXCAVATION OPERATIONS WERE COMPLETED.
2. FREE GROUNDWATER WAS NOT FOUND IN OUR
EXPLORATORY PITS AT THE TIME OF EXCAVATION.
PVC PIPE WAS INSTALLED IN THE PITS, PRIOR TO
BACKFILLING, TO FACILITATE FUTURE CHECKS OF
GROUNDWATER
3. LOCATIONS OF EXPLORATORY PITS ARE
APPROXIMATE.
4 THESE LOGS ARE SUBJECT TO THE EXPLANATIONS,
LIMITATIONS, AND CONCLUSIONS CONTAINED IN THIS
REPORT.
9un!m ary Logs of
Fì[g'"ratrcry
FIG,3
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5
4
3
2
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-2
-3
Ztoız
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APPLIED PRESSURE . KSF
Somple of CLAY, SANDY (CL)
10
DRY UNIT WEIGHT=
MOISTURE CONTENT=
101
17.3 Yo
Swell-Consolidation
Test Results
f00
PCF
From TP-2 AT 3 FEET
LARRY HOWARD
HOWARD RESIDENCE
PROJECT NO. cS06567.000-1 20
ADDITIONAL COMPRESSION UNDER
CONSTANT PRESSURE DUE TO
WETTING,
\
\
1.0
FIG.4
tr
SLOPE
2-3'
SLOPE
PER
OSHA
CO\ER ENNRE YIIDTH OF
*;-;
BELOIY-GRADE WAI.J.
SUP JOINT
DRAIMGE
coMP0sm
(MTRADRA¡N 6000
oR EQUIVA|EIÍT)
ATTACH PI.ASTIC SHEENNC
TO FOUNDANON
E' MINIMUM
OR BEIOND
GRA\EL ìTTM NON-Ï'OVEN
GEOTÐMLE FABRIC (MIRAR
l¿+ON OR EAUVÆINT).
ENC.ASE PIPE IN
GRA\EL ÐfiEND
AI.ID AT I.EASÍ
Ei*TNRE'IRENCH
I.ARRYHOWARD
HOWARD RESIDENCE
PROJECT NO. GSO6567.OOO-1 20
Foundation
Wall Drain
Concept
1:1 SLOPE FROM
BOTTOM OF FOOTNG
(wHrcHEvER ts GREATER)
1:LNCH DIAMEIER PERFORATEÐ RlclD DRATN PtpE.
THE ptpE snour"D BE ptAcED tN A TRENcH ùmi
4_9_LO?t OF AT tEASr trl8-tNcH DROP pER
FOOT OF DRAIN.
1/2'TO 1-1/2'SCREENED
GRAVEL LATERA¡.IY TO FOOÏNG1/2 HAGi{r OF FOOnNC. RtIlTÍH GRA\EL
NOTE:
TTIE BOTTOM OF THE DRAIN SHOUI..D BE AT tEASr 2 NCHES BELOTV BOTTOM OFryqlryc AT TtlE HlcHEst potul At¡D sLopE oownw¡täi-io A Fosint-ô'ÈÃ'ùnyounEr oR To A suup wHERE TTATER cA¡,r BE na¡tlao-sr'puucrNô.
Flo.5
tr
SLOPE
PER
OSHA
COIER ENIIRE TTIDTH OF
SLOPE
DRAIMGE
coMPosm
(MTRADRAIN 6000
oR EauMAtEtff)
ATTACH PI¡SNC SHEENNG
TO FOUNDATON WAIL
E, MINIMUM
OR BEYOND
,- CRAWL SPACE
'MUD sI.âB, oR
BA,RRIER
GRA\EI W|TH NON-WOIEN
GEOTÐ$LE FABRIC (MIRAFI
1¡+0N oR e0uVeueuÌ).
MINIMUM
ENC,ASE PIPE IN
GRA\EL ÐOEND
AtlD AT LEASt
ENNRE TRENCH
I.ARRY HOWARD
HOWAñD RESIDENCE
1:1 SLOPE FROM
BOTTOM OF FOOTING
(wHrcHEvER tS cRF TER)
f:ttcH D|AMETER PERFORATED DRATN ptpE" THEPIPE SHOUI.D BE PTACED IN A IRENCH VrrM /i-slopE oF AT rEASr l/E-tNcH DROP pER FOOTOF DRAIN.
1/2' TO 1-1/2' SCREEI.¡ED
GRAIEL I.AIERAI..LY TO FOOTING1/2 HsC¡{t oF FooINc. RLt-WMI GRAIÆL
NOTE:
DRAIN SHOUT.D BE AT !¡Âqr 2 NCHES BETOW BOTIOM OF FOOTING ATTHE HtcHESr poNT ôND sLOpE DoÌrilwARD-ioï poöirft 'eir¡vrr
OUTI..ET OR TO A SUMP WHERE ìVATER CNÑ EÈ ÈTi'ıVËó'B¡PUMPING.
Foundation
Wall Drain
Concept
sfRucruMt FLOOR
i;.
PROJECT NO. cso6567.OOO_1 20 Flq.6
TABLE ISUMMARY OF LABORATORY TESTINGPROJECT NO. cS06567.000-120ffiDESCRIPTIONq!AY, SANDY (CL)CLAY, SANDY (CL)CLAYSANDY(cL)PASSINGNO. 200SIEVE(%)5155*SWELL(%\-0.6ATTERBERG LIMITSPLASTICITYINDEX(%)1821LIQUIDLIMIT(o/"\3944DRYDENSITY(PCF)101MOISTURECONTENT(%l17.3DEPTH(FEET)5-634-5EXPLORATORYPITTP-1TP-2TP-2* SWELL MEASURED WITH IOOO PSF APPLIED PRESSURE.NEGATIVE VALUE I NDICATES CONSOLI DATION.Page 1 of 1