HomeMy WebLinkAbout; Alicante View Condominium Project; Soils Report; 1982-12-20.-
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Soil Mechanics l Geology l Foundation Engineering
9295ChesopeoksDr.,SuiteE . SonDiego.Colifornio92123 . /714)56&7827
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GEOTECHNICAL INVESTIGATION FOR ALICANTE VIEW CONDOMINIUM PROJECT LA COSTA, CALIFORNIA
FOR
MR. JOHN HELM, ARCHITECT 7682 EL CAMINO REAL, SUITE 202 CARLSBAD, CALIFORNIA 92008
W,O. 284-SD DECEMBER 20, 1982
Los Angel*s Office: (213j 7aw158 . omnge county office: f714J 5478703
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Mr. John Helm, Architect
TABLE OF CONTENT~S
W.O. 284-SD
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INTRODUCTION ................................................ 1
PROPOSED DEVELOPMENT ........................................ 2
SITE INVESTIGATION .......................................... 3
SITE DESCRIPTION ............................................ 4
GEOTECHNICAL CONDITIONS ..................................... 5
EARTH MATERIALS .......................................... 5
BEDROCK ............................................... 5
SOIL DEPOSITS...........................~..~ .......... 6
CHANNEL DEPOSITS ................................... 7
ALLWIUM ........................................... 7
FIU ............................................... 7
DRAINAGE - GROUNDWATER ................................... 9
GEOLOGIC STRUCTURE ....................................... 10
FAULTS - SEISMICITY ...................................... 10
LABORATORY TESTING .......................................... 11
MOISTURE - DENSITY ....................................... 11
LABORATORY STANDARD ...................................... 13 -
CONSOLIDATION ............................................ 13
- EXPANSION TEST ........................................... 14
CONCLUSIONS ................................................. 15
Mr. John Helm, Architect w.0. 284-SD
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TABLE OF CONTENTS (CONTINUED)
RECOMMENDATIONS ..,..,.............,...,.......,...,.,....... 17
SITE PREPARATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
GRADING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..~.......".... 18
FOUNDATION AND RETAINING WALL DESIGN . . ..I....,.....,..... 21
FOUNDATION CONSTRUCTION (NORTH PORTION),..,,..,..,,...... 22
FOUNDATION CONSTRUCTION (SOUTH PORTION).........';........ 24
INSPECTIONS......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...".. 25
PAVEMENT DESIGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
EARTHWORK FACTORS . . . . . . . ..r................................. 21
REVIEW . . . . . . . . . . . . . . . ..*.................................... 27
INVESTIGATION LIMITATIONS ,..,........,..*...,,,.,..,*..,..., 28
ENCLOSURES:
PLATE 1 . . . . . . . . . . . . . . . . . . .
PLATES 2 & 3..............
PLATES 4 & 5 . . . . . . . . . . . . . .
BORING LOGS
TEST PIT LOGS
VICINITY MAP
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Goosoils, Inc.
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Soil Mechanics l 6eology l Foundation Engineering
9295 Chesopeoke Dr., SuiteE . San Diego, California 92123 . (714) 56G7827
December 20, 1982 W.O. 284-51)
Mr. John Helm, Architect 7682 El Camino Real, Suite 202 Carlsbad, California 92008
Subject: Geotechnical Investigation For Alicante View Condominium Project La Costa, City of Carlsbad, California.
Dear Mr. Helm,
GeoSoils, Incorporated has completed an investigation of the subject
property. The site consists of a nearly level, previously graded
parcel south of Alicante Road in the La Costa area, This transmittal
summarizes geologic and soils engineering conditions underlying
the property and presents development and construction recommendations
which are consistent with the indicated conditions.
Pertinent geotechnical data is graphically presented on the Exploration
Map enclosed with this transmittal as Plate 1. The map utilizes a
one inch equals 50 foot scale topographic base map prepared by Rick
Engineering.
Lo6 An&s Office: f213J 7E-2158 . m CounIyOf+x (n4J 547.&‘03
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Mr. John Helm, Architect
PROPOSED DEVELOPMENT
Page 2 December 30, 1982 W.O. 284-SD
Details of the proposed development are currently unavailable.
However, we understand that the property is planned to support
multi-story, condominium - townhouse units with a network of
interior roadways. Finished grades will be very near existing
surface levels.
Preliminary plans indicate the creation of small graded slopes
throughout which do not exceed a vertical height of 12 feet.
Small retaining walls will mark the toe of many of the slopes.
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SITE INVESTIGATION
Our field investigation included a series of studies extending
from early 1981 to recently. Previous work included explorations
on expanded areas of La Costa of which the subject property was a
part. Geotechnical conditions were determined from the following
activities:
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Field mapping of available outcrops and exposures.
A study of available technical literature, as well as
stereoscopic aerial photographs of the La Costa area.
Drilling of five exploratory borings and 15 exploratory
test pits at selected locations on the property. The
test excavations were logged by our field geologist and
representative samples of underlying earth materials were
retained for laboratory testing. Logs of the borings and
test pits are enclosed.
Engineering analysis based upon the results of laboratory
testing.
The preparation of this report including the enclosed map
and cross-sections.
Goosofls, Inc.
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Mr. John Helm, Architect
SITE DESCRIPTION
Page 4 December 30, 1982 W.O. 284-SD
The subject property is situated between La Costa County Club
golf course and Alicante Road at Altisma Way. A,ccess is provided
by Alicante Road which also defines the northern property boundary.
Much of the property is nearly level with gently descending
terrain southward toward a small, concrete drainage ditch along
the southern property margin. Small, graded slopes descend from
Alicante Road onto the site.
Existing surface levels have resulted from previous grading efforts.
Much of this included borrow grading chiefly for the construction
of the adjacent golf course. This resulted in filling along the
south margin of the property into the broad canyon areas of San
Marcos Creek. Subsequent dump filling has added isolated deposits
of rock debris and fill soils throughout the property:
Grading records are unavailable. However, an earlier topographic
map which depicts pregrading conditions has been reviewed during
the course of this study.
Goosoils, znc.
VICINITY MAP
DATE 1 - 83
Soil Mdanict l hology l Foundation Enginmring
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GEOTECHNICAL CONDITIONS
Page 5 December 30, 1982 W.O. 284-SD
The subject property is situated within lower hillside areas
along the north margin of San Marcos Creek prior to its transition
into Batiquitos Lagoon. Level areas on-site have resulted from
previous grading efforts.
EARTH MATERIALS
The property is underlain by a complex series of various soil
deposits atop older bedrock units. The following materials are
recognised:
BEDROCK Bedrock units are exposed near the surface in
the northwest portion of the property. Surface outcrops
were studied in nearby road cuts above Alicante Road.
Additional exposures were developed on the site at depth
within the exploratory test pits.
The exposed bedrock has been included within a variable
series of sandstone-siltstone units designated the Delmar
Formation of Eocene age. These units are extensively
exposed throughout areas of La Costa west of the subject
property. On-site the bedrock consists chiefly of sand-
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Mr. John Helm, Architect Pacje 6 December 30, 1982 W.O. 284-SD
stone with minor siltstone units. Sandstones are
commonly friable to weakly cemented in upper, moie
weathered exposures. Siltstone units contain a
high percentage of clay minerals.
A thin cover of natural topsoil mantles the bedrock
in several subsurface exposures. The topsoil repre-
sents a weathered relfection of the underlying rock
unit and ranges from sandy silt to silty ciay.
SOIL DEPOSITS - Several natural and artificial soii
deposits occur throughout the surface and at depth
atop bedrock units of the subject property, A wide
variety of soil, including coarse sand to soft, wet
clays were encountered. An understanding of the soil
deposits, their distribution and engineering properties
is necessary for an effective and successful site
development. The following soil deposits are recognized
on the property:
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1. Channel Deposits - These soils consist chiefly of
coarse sands with gravels. Channel deposit soils
represent eroded debris which was naturally deposited
into small canyons descending southward across the
property. On-site, channel deposit soils were
encountered within test pit excavations in the
central areas. These soils are non-expansive and
will provide a convenient source for lot capping or
high quality utility trench backfill soil.
2. Alluvium - Natural alluvial soils dominate the
subsurface throughout the southern areas of the
property. The alluvium occurs in a wedge-shaped
deposit which thickens southward toward the golf
course, (see cross-sections), Exposures were
developed chiefly at depth within the exploratory
excavations. The alluvial soils which represent
natural laqoonal processes within San Marcos,Creek,
consist of dark colored clay-silt soils in a soft
to stiff condition.
3. Fill - Fill soils occur throughout the surface areas
of the property. These included graded fills which
appear to have received some compactive effort,~as
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well as more recent dump fill deposits. Additionally,
areas along the south and east margin have been
utilized for the burial of unsuitable soils from
nearby grading projects east of the site, These soils,
which contain excessive quanitites of over-sized rock
debris, have been approximately delineated on Plate 1.
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The fill soils typically consist of sand-silt
mixtures with varying quantities of rock debris,
The soils range in thickness from less than one
foot to a maximum indicated depth of 12 feet from
existing surface levels.
- Details of the underlying earth materials are given on the enclosed
Boring and Test Pit Logs. These indicated subsurface relationships
are approximately shown on cross-sections attached as Plates 2 and 3.
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Mr. John Helm, Architect Page 9 December 30, 1982 W.O. 284-SD
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DRAINAGE - GRODNDWATER
Surface drainage consists largely of waters falling onto the
site. Runoff sheet-flows southward into the concrete drainage
ditch along the southern property line. No evidence of scouring
or excessive erosion resulting from concentrated runoff was noted.
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Groundwater was encountered at depth within exploratory excavations
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occurs chiefly within alluvial soils at depths as shallow as 8 feet -
from existing surface levels, (see Test Pit Logs). Groundwater in
- the affected areas likely reflects subsurface drainage from higher
areas to the north as well as local irrigation of the nearby golf
- course.
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GEOLOGIC STRUCTURE
Page 19 December 30, 1982 wo 284-SD
Available exposures of Delmar Formation sediments on-site and
within outcrops on adjacent properties suggest near horizontal
bedding structure within the bedrock. Bedding planes are typically
crudely developed.
FAULTS - SEISMICITY
Faults or significant shear zones were not encountered within the
bedrock on or in near proximity to the property. However, as with
most Southern California areas, the La Costa area lies within a
seismically active zone. Active fault zones, including the San
Andreas and San Jacinto Faults lie within sufficient proximity to
the site to affect the development during its lifetime. Light to
moderate ground shaking during periods of activity along distant
faults may be anticipated. Ground separation as a result of seismic
activity is not expected.
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MOISTURE - DENSITY
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LABORATORY TESTING
Page 11 December 30, 1982
w.0. 284~SD
Representative samples of underlying earth materials were retained
from the exploratory excavations as indicated on the enclosed logs.
Bulk and relatively undisturbed samples were obtained. The samples
were transported in moisture resistant containers to the laboratory
for testing and analysis. The following tests were performed:
Selected undisturbed samples were subjected to dry unit weight and
field moisture determinations. This data is useful for in-place
soil consistency determinations. Dry unit weight is determined in
pounds per cubic foot and the field moisture is given as a percentage
of the dry unit weight. The following data has resulted:
DEPTH EARTH DRY DENSITY EXCAVATION (feet) MATERIAL (pcf)
B-4 Fill 107.3 Bedrock 110.1 20.0 Bedrock 114.8 25.0 Bedrock 108.2
B-10 5.0 Alluvium 115.3 16.0 10.0 Alluvium 103.4 23.0 15.0 Alluvium 108.1 18.5
MOISTURE (percent)
18.6 10.8 15.7 18.9
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TP-2
TP-6
TP-7
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TP-8
TP-9
TP-10
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TP-11
TP-12
TP-13
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DEPTH EARTH DRY DENSITY MOISTURE (feet) MATERIAL (pcf) (Percent)
8.0'
8.0
11.0
15.0
9.0
12.0
10.0
12.0
11.0
7.0
6.0
13.0
Topsoil
Alluvium
Alluvium
Alluvium
Alluvium
Alluvium
Alluvium
Alluvium
Alluvium
103.6
110.7
76.1
96.0
115.8
101.8
93.6
102.8
90.3
Trench Backfill 104.7
Fill 109.7
Alluvium 101.5
18.2
16.1
41.5
22.4
15.1
22.8
26.3
23.0
31.6
21.5
20.6
23.0
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LABORATORY STANDARD
The maximum density and optimum moisture content were determined
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of the anticipated site grading will utilize these tested soils.
- The test procedure utilized was in accordance with ASTM D-1557-70,
the five layer method. The following results are indicated: -
- TEST DEPTH MAXIMUM PIT# (feet) SOIL TYPE DENSITY OPTIMUM MOISTURE
,- TP-1 5.0 Tan silty sand (bedrock) 111.5pcf 18.0%
- TP-6 3.0 Brown clayey silt (alluvium) 124.5pcf 10.5%
-. TP-8 8.0 Sand 119.0pcf 17.5% (channel deposit)
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- CONSOLIDATION
- Consolidation tests were performed on selected, undisturbed samples
of alluvial soils in order to estimate their settlement characteristics
- when loaded. The consolidation apparatus is designed to receive the
one inch high brass rings which retain the samples. Loads are .-
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December 30, 1982 w.0. 284-SD
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applied in several increments in a geometric progression while
the resulting deformations are recorded at selected time intervals.
Porus stones are placed in contact with the top and bottom of each
specimen to permit the addition and release of pore fluid. In-
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undation of the samples is performed at the initial load. Results
of the consolidation tests are presented on the enclosed Plates 4
and 5.
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EXPANSION TEST
An expansion test was performed on a remolded sample of repre-
sentative surface soil. The air dried sample was placed under a
surcharge load of 60 pounds per square foot for 24 hours after allowing
water to contact the sample. The percent expansion was recorded as
the amount of vertical rise compared to the original one inch sample
height. Results of the expansion test are given beloti:
TEST DEPTH PIT# (feet) MATERIAL PERCENT EXPANSION
1 5.0 Sandstone- Siltstone 5.2
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Mr. John Helm, Architect Page 16 December 30, 1982 w.0. 284-SD
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On-site fill should be removed, cleansed of over-sized
rock and may be reused in properly compacted fill. Some
of the rock debris may be incorporated into the regraded
fill in accordance with recommendations given below.
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3. Soft, Compressible Alluvial Soils - Soft, saturated
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alluvial soils underlie the fill in the southern margin
of the site. Potentially adverse affects of building atop
these deposits can best be averted by ensuring that an
adequate section of recompacted fill is placed atop these
soils. Detailed recommendations for this procedure are
given in the "Site Preparation" section below. Specialized
foundations are recommended in these'areas as outlined in
a following section and shown on Plate 1.
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Mr. John Helm, Architect Page 15 December 30, 1982 W.O. 284-SD
CONCLUSIONS
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Based upon our investigation of the subject property, development
of the site, substantially as proposed, is feasible from a
geologic and soils engineering viewpoint. However, geotechnical
conditions which preclude conventional development techniques were
encountered during our site investigation. The conditions and
the recommended mitigating measures are outlined below:
1. Expansive Earth Materials - On-site bedrock (siltstone),
alluvium and selected fill soils are known to be expansive.
Similar soils have resulted in distressed foundations and
paved structures in near-by areas of La Costa. Grading
recommendations given below are intended to mitigate the
potentially adverse affects of on-site expansive materials
on the planned improvements.
2. Existing, Uncompacted Fill Soils - Much of the fill present
on the property is in a loose condition with soft natural
soils directly beneath. Additionally, some of the fill
contains excessive, over-sized rock debris wasted from
previous near-by grading projects.
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Mr. 'John Helm, Architect Page 17 December 30, 1982 w.0. 284-SD
RECOMMENDATIONS
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The recommendations given herein have resulted from a knowledge
of the above site conditions with which they are consistent. The
recommendations should be reflected in finalised plans and im-
plemented during the construction phase:
SITE PREPARATION
1. Graded fill slopes should be programmed for 2:l (horizontal
to vertical) gradients. Cut slopes may be planned for
1 l/2:1 gradients.
2. Finish pad grades in the southern portion of the site,
adjacent to the golf course, should maintain finish grades
at or above existing levels (and above anticipated flood
elevations).
3. Finalized plans should reflect removal depths given on
Plate 1. The plans should be reviewed and approved by
this office.
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GRADING
Page 18 December 30, 1982 w-0. 284-5~
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Stable building areas can best be created by utilising the
following grading techniques:
1. Recommended removal depths (from existing levels) are
given on Plate 1. This grading is expected to result
in (a) the removal of on-site fill soil, (b) the removal
of upper, soft alluvial soil, (c) the removal of near-
surface expansive bedrock materials so that uniform
foundation conditions result..
2. As an alternative to complete removal of lagOOna
and soft compressible soils which could necessitate
excavations on the order of 20 feet deep, the recommended
approach is to provide approximately five feet of compacted
granular material in the zone immediately beneath the
planned foundations and design the foundations to perform
as "floating" rigid membranes. The described approach, it
should be understood, does not alleviate settlement, but
rather provides that the individual structures may settle
and remain substantially intact as well as in the same
plane thus minimizing the adverse affects generally
associated with settlements. In those areas underlain
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currently by uncompacted fill materials, an alternative
may be considered short of removing the entire depth of
fill and recompacting that material. The alternative
consists of removing and recompacting approximately one-
half of the fill depth, or a minimum of five feet, provided
special foundations are designed in those areas. The
special foundations should incorporate the same sort of
approach as described above for foundations supported on
the compressible alluvium soils.
The recommended removal depths, as indicated on Plate 1,
have been prepared to show complete removal of existing,
uncompacted fill deposits and on the order of five to six
feet in those areas underlain by the soft, compressible
alluvium soils. If, as the planning for this project
proceeds, it becomes advantageous to consider removing
less than the total depth indicated of the existing un-
compacted fill, the plan can be revised to indicate reduced
removal depths and corresponding areas where special
foundations will be required.
3. Channel deposit sands and other non-expansive soils within
the fill may be stockpiled for reuse as finish grade soil,
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4. All removals should be inspected and approved by
representatives of this office prior to filling.
5. Compacted fill soils should be placed only, in areas
approved by this office. Attempts should be made to
utilize more expansive soils in the deeper fills.
Fill soils should be brought to near optimum moisture
levels, and mechanically compacted to a minimum 90
percent of the laboratory standard (ASTM D-1557).
6. Rocks which exceed 8 inches in diameter may be selectively
incorporated into the deeper fill1 in isolated examples,
Care should be taken to provide adequate compaction around
the rock and to prevent nesting of rocks. Excessively
rocky fill may be utilized to stablize and provide working
areas atop soft mud deposits after removals,
7. Fill slopes should achieve 90 percent compaction to the
outer slope face. This can best be achieved by over filling
the slope three feet and cutting back to the design configuration.
8. Graded slopes should be planted as soon as possible after
construction. Deep rooted plant types recommended by the
project landscape architect should be utilized.
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FOUNDATION AND RETAINING WALL DESIGN
The following design data may be utilized for on-site foundations
after completion of the above recommended grading:
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An allowable bearing value of 1500 pounds per square foot
may be utilised for graded surface soils at the recommended
footing depths given below. This value may be increased by
one third for short duration seismic or wind loads.
The active earth pressure to be utilized for retaining wall
design may be computed as an equivalent fluid having a
density of 35 pounds per cubic foot when the slope of the
backfill behind the wall is level. Where the slope of the
backfill is 2:1, an equivalent fluid pressure of 45 pounds
per cubic foot may be used.
Passive earth pressure may be computed as an equivalent fluid
having a density of 250 pounds per cubic foot, with a maximum
earth pressure of 1500 pounds per square foot.
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Mr. John Helm, Architect Page 22 December 30, 1982 W.O. 284-SD
4. An allowable coefficient of friction between soil and
concrete of 0.4 may be used with the dead load forces.
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5. When combining passive pressure and frictional resistance,
the passive pressure component should be reduced by one-
third.
FOUNDATION CONSTRUCTION (NORTH PORTION)
Conventional foundations may be utilized over much of the property
(excluding areas along the south margin as shown on Plate 11, after
completion of the recommended grading. The conventional foundations
should be constructed in accordance with the recommendations given
below which are presented for estimating purposes and should be
verified at the completion of grading when the character of the
surface soils is known.
1. Exterior footings should be founded at a minimum'depth
of 18 inches below the lowest adjacent ground surface.
Interior footings may be founded at a depth of 12 inches
below the lowest adjacent ground surface. All footings
should have one Number 4 reinforcing bar placed at the
top and bottom of the footing.
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2. A tie beam 12 inches by 12 inches, reinforced as above,
should be provided across the garage entrances. The
base of the tie beam should be at the same elevation as
the adjoining footings.
3. Concrete slabs, except in garage areas, shall be underlain
with a vapor barrier consisting of a minimum of 6 mil
polyvinyl chloride membrane with all laps sealed. This
membrane shall be covered with a minimum of one inch of
sand to aid in the uniform curing of the concrete.
4. Concrete slabs should be reinforced with 6 inch by 6 inch,
Number 10 by Number 10 welded wire mesh. All slab rein-
forcement should be supported to ensure proper positioning
during placement of concrete.
5. Presaturation is recommended for these soil conditions.
The moisture content of the subgrade soils should be greater
than optimum moisture to a depth of 18 inches below grade
in the slab areas.
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FOUNDATION CONSTRUCTION (SOUTH PORTION)
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Specialized foundations should be utilized over areas along the
southern portion as shown on Plate 1. These foundations should
be designed and constructed in accordance with the following:
1. Continuous exterior footings should be founded a
minimum depth of 24 inches below the lowest adlacent
ground surface. Interior footings should be founded
a depth of 18 inches below grade. All footings should
be reinforced with four Number 5 bars, two near the
top and two near the bottom of the footings. Additional
grade beams should be provided to result in an interval
between grade beams of about 15 feet. It is recommended
that specific criteria be discussed when foundation detai
and configurations are better defined.
2. The above footing recommendations are to be constructed
over a minimum of five feet of compacted structural fill
consisting of granular on-site soils or other acceptable
materials.
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INSPECTIONS
During grading operations, continuous field inspections should be
conducted by the project soils engineer or his designated field
representative. The following items should be inspected, tested
and approved:
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Removals should be approved to verify their adequacy.
The compaction of fill soils should be periodically tested.
Rock disposal and burial techniques should be approved.
Fill slope construction should be approved.
Approval of fill cap soils with a low expansion potential.
Graded cut slopes should be inspected and approved by the
project engineering geologist.
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Mr. John Helm, Architect
PAVEMENT DESIGN
Page 26 December 30, 1982 W.O. 284-SD
At the present time no laboratory tests have been performed to
provide pavement design criteria. Sampling and testing of sub,
grade materials are not with the scope of this preliminary
investigation and will be undertaken at the completion of rough
grading. In the meantime, to aid with planning it,is recommended
that an "R"-value of 20 be assumed for the generally silty site
soils. Using a traffic index of five, the following pavement
section alternatives may be used:
A.C. THICKNESS
2 "
2 "
3 "
3 "
AGGREGATE BASE COURSE
CLASS II D.G,
12 "
9 "
6 "
9 "
- GeoSoffs, Inc.
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Mr. John Helm, Architect
EARTHWORK FACTORS
Page 27 December 30, 1982
w.0. 284-5~
Grading of the site is expected to result in a shrinkage in
volume of five to ten percent for near surface soils (approximate
depth two to three feet). Excavation of deeper materials should
result in a bulking of zero to five percent. Shrinkage - bulking
factors are based on a relative compaction after grading of 90 to
93 percent.
REVIEW
The final foundation and grading plans should be reviewed by this
office to minimise any misunderstandings between the plans and
the recommendations presented herein. In addition, foundation
excavations and earthwork performed at the site should be evaluated
by a qualified engineering geologist or soils engineer. If conditions
are found to differ substantially from those stated, appropriate
recommendations should be requested.
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The opportunity to be of service is sincerely appreciated, and if
you should have any questions pertaining to this report, please feel
welcome to contact our office.
Mr. John Helm, Architct
INVESTIGATION LIMITATIONS
Page 28 December 30, 1982 W.O. 284-SD
The materials encountered on the project site and utilized in our
laboratory investigation are believed to be representative of the
total area; however, soil and bedrock materials vary in characteristics
between excavations and natural outcrops.
Since our investigation is based upon the site materials observed,
selective laboratory testing and engineering analyses, the conclusions
and recommendations are professional opinions. These opinions have
been derived in accordance with current standards of practice and no
warranty is expressed or implied.
Respectfully submitted, GeoSoils, Incorporated
&a-?+ m-i
Dennis Middleton, CEG 980 Engineering Geologist
RWV
/DM/
/em
Gcosoits, Inc.
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Mr. John Helm, Architect W.O. 284-SD
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PLATES 4 & 5
GeoSoils, Znc.
I G c. l CONSOLIDATION- PRESSURE CURVE
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CLIENT /f&?-M “&:7-” Qcr&e. W.O.
PROJECT DATE
UNDlSTUi~iOLDED~
//S/i 2
LOCAtlON
CONSOLIDATION-PRESSURE CURVE
NORMAL PRESSURE KIPS par Sq. Ft.
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CONSOLIOATION- PRESSURE CURVE
CLIENT //ELti 9L W.O.
PROJECT DATE
“NDISTUiiOLDED~
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LOCATION
7-P-/0 e- IO/ DEPTH FT.
CONSOLIDATION-PRESSURE CURVE
NORMAL PRESSURE KIPS per Sq. Ft.
Mr. John Helm, Architect
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W.O. 284-SD
BORING LOGS
BORING LOG 1
CLIENT Helm W.O. 284-%A~E DRILLED .l-22-84~~~~D SY DM
PROJECT <SURFACE ELEV. 362 DRIVING WT. 2400 lb
FILL (af): Light brown Clayey Silt with Sand. Dry to very slightly moist, loose.
From 4 feet; up to 50% hard .' volcanic rock fragments, slow drilling.
End of boring at 8 feet. Drill bucket refused by numerous _ rock. No water or caving.
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BORING LOGL
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CLIENT- W.O.284-SB DATE DRILLED I-22-81 LOGGED BY&Z,
PROJECT SURFACE ELEV. 36’lt DRIVING WT. 2400lb
FUC: light brown silty sand, moist,
dense, mottled.
Dark brown sandy silt, moist, slightly
porous.
BEDROCK: green silty clay, moist, hard,
slightly porous. F L Light green sandy clay, moist, hard.
Clayey sand,’ light green, moist to very
moist. very dense. mottled.
Brown clayey sand with rock fragments to
8 inches, moist, mottled, difficult drilling
Red-brown silty fine sand with rock fragment,-
to 8 inches, moist. Difficult drilling.
Slight water seepage at 17 feet.
Light gray slightly silty sandstone, very
dense.
End Boring At 25.Feet.
Slight water seepage at 17 feet.
No caving.
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110
14.
38.
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10.8
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18.5 .
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C. BORING LOG-l&
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CLlENT2.4.m W.O. &I.% DATE DRILLED B-26-& LOGGED BY&X PROJECT SURFACE ELEV. 25 DRIVING WT. 215olb<.
FILL: clayey silt,
mf, damp.
medi urn orange-brown,
4LLUVIUM: medium to dark brown clayey
silt, firm, damp.
Dark brown silty clay, moist,
orange mottling.
At 10 feet, seepage, firm, wet,
dark brown silty clay, orange
mottling.
Mottled grayish-green and dark
brown clayey silt, moist, firm.
Medium to dark brown sandy silt,
soft, very moist.
Angular rock fragments, (2 inches
in diameter) in orangish-brown
silty sand, wet, caving, drilling
haulted.
rOTAL DEPTH 19.5 FEET.
dater at 10 feet.
Zaving at I9 feet.
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15.
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08.
BORING LOGz
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CLIENT. He1m W. O.-+$$=GDDATE DRILLEbe@-s?-*lLOGGED BY.- Dl4
PROJECT SURFACE ELEV. 2 23 DRIVING WT.
FILL (af)(?): Light brown Sandy Silt, with clay, desiccated.
At 2 to 4 feet, medium brown Clayey Silt, stiff, small rock -- fragments, with some cobble-size _ fragments, damp with increasing moisture downward.
At 5 feet, soil material quickens -
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dark brown Silty Sand (with littlr
~~~~Eb"%%P~~d~~~yo'o~~~k~~t i:'
Total Depth G feet. Water at 5 feet. Soil Liquefied at 5 feet.
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2: v)k oz x0"
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BORING LOG 18
CLIENT .~He~&i W. 0. 284-SDDATE DRlLLEb a-27-8lLOGGED BYE-
PROJECT- SURFACE ELEV. + 22 DRIVING WT.
1 FIL;e~;~~;te;;rk brown Silty Clay,
At 1.5 feet, grading to medium orangish brown Sandy Silt, desic-.. cated with cobble-size rock fragments, some subround cobbles present.
At 4 feet, medium brown Clayey very stiff, damp, subround - to angular rock fragments (up to _ 2 inches) present in large numbers)
rock fragments cause
Total Depth 5 feet. No Water.
No Caving.
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TEST PIT LOGS
Gcosoizs, Inc.
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TP-I
FILL : Medium
BEDROCK: .5Wstonc, sm&. Crv to rusf brown co/or. Mauk, hard
Total Dtpfi 5 N
TP-2
FILL: Medim brown LGe sandy silt. /‘bit, moderaf+
brown Sand Sl&
TOPSOIL: Da&
mxfera fe& f/;m .
sandy silt. /%dt
rota/ mpfh - /o ’
TP-3
Si/i. S/pf$ moGf, Compact.
CHANN.EL DEPOSIT : sand - Gravel. B&F to wh;fC co/or,
rusr- brown seams - hor~zonfal strahir;cat/~n.
non - cohesie.
rota/ Depfh I/’
TEST PIT LOGS
Soil Mschmict l 6dogy l bmd&tiiA EnginwinO
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TP-4
mNfi7 @’ CHANNEL DEPOSIT: Sand- Grave/. White with horizonhI rwf-
7’ coJored scams and gravel beds. More and I+er
2 rave / ah 2 homontal base. Dry, na-,- cohesiir.
sanddone, Ly,t yey co/or:
rota/ Dcprx - IO ’
TP-5
BEDROCK: Sandstone, a/$. Lyht JrCy dor.
Frstb/e, mobi.
sand malii*.
avNA.
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TP-6
MYM-
TOPSOIL -ALLUVIUM : Med,um brow clayey Silt with small
white cahihe d∨&. S/Thtb moJt, herd
f ram 4’ f yr”fdes
modera eb
f; bra,, /5r;e s.m$ Sit MO/it
‘f-n? 0 moueraafc~ so&
BEDROCK: S’ftsione, c@y. Rust- bnwur, co& Mass&,
becomes / below. 57?-&%?. I
Tofa/ L+fh - /s ’ R&y+
TEST PIT LOGS
DATE 12-81 IW.O.NO.284IBy-
Soil ktchmicr l Galogy l found8tiin ErifwinO
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TP-7
with up to 70% volcan,‘c
from 5,' rocK N)creases to sol: - up fo 20' dam.
Minor caving s/ows d$t/irg.
7otal Depfh - /6’
&IX sampk fL?l ///I
R;? sarn$e /“mm /5
TP-8
7sIWHA . FILL: Grey - brwn, -5and-5i/t mutwe with hi h
of smd rock Frqmenfs. Dry to ?
percenf
s/&h fi ma/j/,
6%’ /00se.
,fmm --t-6; ,zo”.~
hp7enfs 10
of 70% vo/twic ?vch-
sad ma hi*.
ALLUVWM : Medkn brown fo yey &;ffIed) c&y
S,it with & ~Jnd. MO/~< rnob’rr~/~+ sfi//
Q 13; Gmunds/sfe~
Tafal Depfh - 16 *
TEST PIT LOGS
&E 12 -82 ~W.O.NO.784~C&L?L
Soil Mechanics l Wogy l Foundd~~ Engimrrinfj
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TP-9
W .+-- ah’ FILL : 6mwn f+Imfs c&T $2, with rmafl scatterad
ALLUVIUM: DwK drown clayey Jilt. Motit,
/km 124 ’ SmN water 5eeps. sbi/ /;
fo St,./{ May Fade I&,
bedrocK J; 6offom.
Tota/ Depfh - /6 ’ R,irT s.nph AnI /2’
TP- IO
silfy he sand to c/ayr s/i/t
f&m 3,’ CO&!& s-z sm~/! DOCK frayment!.
soil frachlon /i
TP-II
R/5 5aryle Am 10 t
BUK Se.+.. /mm 11’
R+ Sampe i&n I?’
FILL: Rust - brown sil+ Sand. MoGt , /;;m.
ALLUVIUM : Med&, brown sandy=o;;lt w~fh occaskai
cobbles. MO&?, moderate/y
BEDROCK : -Sandstone - Siftstone . yellow fo u&Ii c&r.
Weafhered io so/f mnhhncy h 2; t&&e b&“.
Zfa/ De#h - /4’
TEST PIT LOGS
FATE J2-82 W.O. NO. 284 BY D.
Sail Mtchmict l Bmlq~y l Foudation Erqinemring
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Tofal Depth J2% ’
TP- 13
F)LL: Brown, Lnc sady Silt to d$ Sand. Mob
T&a/ Depfh Jb ’
TEST PIT LOGS
DATE U-82
Sail Mechanics s 6Jen 0 Fadtiin Enginwiw
TP-14
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BEDROCK : Sandsfone . We/f- cemented. hbd
Tofsl Depfh - 10’
TP-15
#+?+A* ’ y Midtim brown Ahe sw& ~ilf wifh &y
flv--zr;*
6’ b perCenf.+!e Of cobbfes. Mout, /we.
BEDROCK : Sanu!!f~ne - 5rhstone . Well- cemented
&dK Sk&! lb7 8’
70fal Depfh - f0'
TEST PIT LOGS
DATE Jz-82 W.O. NO. 284 BY .L?. M.
Soil Mechanics l Gdogy l Foundrtin Lngimrring