HomeMy WebLinkAboutParcel Map 12887 Parcel 2-3 Geotechnical Rough Grading
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LAKESHORE
Engineering
Established 1985
Consulting Civil Engineers
June 8, 2005
Project No. 04-070. UR
To: City of Temecula, Department of Public Works
Client: Mr. Mike Augustine C/O Augustine Construction
31552-1 Railroad Canyon Road
Canyon Lake, CA 92587 (951) 232-9794
Subject: Update Rough Grading Compaction Report
Two Proposed Single Family Homes
Parcel 2 & 3 of Parcel map No. 12887
Santiago Road, Temecula, CA.
LD 04-248GR
Reference: Geotechnical Report of Rough Grading
Parcels 2 & 3, P.M. 12887, Santiago Road
Project No. 104470-30, Report Dated August 17, 2004
Prepared by LGC, Inc. for Augustine Development Corporation
Gentlemen;
This report is written with a two fold purpose: a) to notifY the City of Temecula that Lakeshore Engineering
has been retained to be the geotechnical/soils consultant of record for the subject parcels and b) to provide
an update rough grade compaction report.
Our scope of work consisted of the following: a) conduct a site inspection for any supplemental
changes/grading made to manufactured pads and to determine the suitability of the pads for its intended use,
b) reviewed the above referenced compaction report prepared by LGC Inland, Inc., and c) review of the As-
Built Grading Plan prepared by Vandenberg Civil Consulting.
BACKGROUND INFORMA nON
The subject properties are rough graded sites, with earthwork conducted during the months of April through
May of year 2004. The pads were manufactured under the inspection and testing services ofLGC, Inc, with
summary of findings, recommendations and conclusions presented in their rough grade compaction report,
dated August17, 2004 (see appendix).
Grading plans were prepared by Vandenberg Civil Consulting, with As-Built Plans prepared in June of year
2005. As understood by us, at the conclusion of the rough grading operation in June of year 2004, the lower
building pad (parcel no. 2) ) was built to finished pad elevation of F.P. =1111.0, and the upper building pad
(Parcel No.3) was built to finished pad elevation of F.P = 1135.0.
31520-A Railroad Canyon Road' Canyon Lake, CA 92587 . (909) 244-2913 . FAX: (909) 244-2987
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June 8, 2005
Project No. 04-070.UR
Page Two
The upper pad was used as a borrow site for the recent street construction fronting both subject parcels.
Supplemental grading has lowered the pad grade by about 6 Y2 feet to a finished pad elevation of F.P.=
1128.50. The entire building pad is a truncated cut pad. There were no fills placed and/or fill slopes
manufactured on Parcel No.3. Onsite cut slope is now approximately 29 feet high, pitched at 2:1/H:V.
SITE OBSERV A nONS
Our site inspection conducted on the afternoon of June 7, 2005, indicated the following:
PARCEL NO.2 (LOWER BUILDING PAD)
Parcel No.2 has not been disturbed since the conclusion of the original rough grading operation conducted
in June of year 2004. Except for minor reveling of less than 5-6 inches deep, the existing fill and cut slopes
are not showing any distress, with surface contours smooth and uniform. The building pad is also in good
condition with no signs of surface erosion.
Except for minor soil erosion along side driveway swale flowline (to be concrete lined V -ditch), proposed
graded driveway surface appears to be free of distress and/or erosion and in good working order.
PARCEL NO.3 (UPPER BUILDING PAD)
Based on our site inspection and review of references plans (original and as-built plans), the building pad is
situated along a (truncated) ridge nose. The pad has undergone supplemental grading and lowered by
approximately 6 Y2 feet (from elevation 1135.0 to 1128.5). Associated resulting grading changes included
the increase in cut slope height to the north corner of the lot, and the reduction of driveway slope pitch to a
maximum of 15 percent grade.
CONCLUSIONS AND RECOMMENDATIONS
Based on our knowledge of the subject two sites and past work experience in the area, it is our opinion that
. the findings, conclusions and recommendations presented the above reference rogh grade compaction report
prepared by LGC, Inc., remains applicable. Unless superseded below, the findings, conclusion and
recommendations presented in the reference compaction report (xerox copy attached in appendix) should be
incorporated into the planning, design and construction stages of proposed construction.
The existing building pads in our opinion, are considered suitable for construction of single family homes as
planned. Consideration for the removal of organic (from annual grass) root hairs in existing topsoil (upper
2-3 inches) should be given prior to concrete slab-on-grade pour. The upper soils should be removed prior to
placement of vis queen barrier and replaced with clean import granular sand.
Organic dirt resulting from surface soil removal should not be used or incorporated into structural fills
unless they are reworked as engineered fill, under inspection and testing.
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June 8, 2005
Project No. 04-070.UR
Page Three
FOOnNG TRENCH INSPECnON
All footing trench excavations should be inspected and approved by consultant prior to placement of forms,
reinforcements, or concrete pour. Materials generate from the footing trench excavations should not be
spread on slab-on-grade areas, provided they are compacted and tested.
SITE DRAINAGE
Drainage concentration created from the construction of house pad and grading operation should be directed
away from leach field areas by the means of permanent V -ditches and/or manufactured drainage swale and
flowlines.
The homeowner should be made aware of the potential problems which may develop when drainage is
altered through the construction of garden walls, patios, pools and gazebos. Ponding water situations,
leaking irrigation systems, over watering or other conditions which could lead to ground saturation must be
avoided.
GENERAL INFORMATION AND CLOSURE
The findings and recommendations of the report were prepared in accordance with generally accepted
professional principles and practice in the field of geotechnical engineering. This warranty is in lieu of all
other warranties, either express or implied.
Lakeshore Engineering ~
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APPENDIX
REFERNCE ROUGH GRADING COMPACTION REPORT
BY LGC. INC.. REPORT DATED AUGUST 17.2005
Lakeshore Engineering
=:
tm INLAND, INC.
Geotechnical Consulting
GEOTECHNICAL REPORT OF ROUGH GRADING
PARCELS 2 AND 3 OF PARCEL MAP 12887
SANTIAGO ROAD, CITY OF TEMECULA
RIVERSIDE COUNTY, CALIFORNIA
Project No. I04470-30
Dated: August 17, 2004
Prepared For:
Mr, Mike Augustine
AUGUSTINE DEVELOPMENT CORPORATION
31552-1 Railroad Canyon Road
Canyon Lake, California 92587
(p
140935 County Center Drive' Suite A' Temecula, CA 92591 ' (951) 719-1076' Fax (951) 719-1077
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Em INLAND, INC.
Geotechnical Consulting
August 17, 2004
Project No, 104470-30.
Mr, Mike Augustine
AUGUSTINE DEVELOPMENT CORPORATION
31552-1 Railroad Canyon Road
Canyon Lake, California 92587
Subject:
Geotechnical Report of Rough Grading, Parcels 2 and 3 of Parcel Map 12887, Santiago Road,
City of Temecula, Riverside County, California
References:
T,HE. Soils Co., 1nc., 2002, Preliminary Geotechnical Investigation. Proposed 5*-Acre. 2-Lot Residential
Development. North of Santiago Road, East of the 2"d San Diego Aqueduct, City of Temecula. Riverside
County, California, Work Order No, 408201,OOR, dated June 21,
Vandenberg Civil Consulting. Precise Grading Plan, 30-Scale. Parcels No, 2 & 3 of Parcel Map 12887.
undated.
This report presents a summary ofthe observation and testing services provided by LGC Inland, Inc" (LGC) during
rough grading operations to develop the subject site in the City of Temecula, Riverside County, California,
Conclusions and recommendations pertaining to the suitability of the grading for the proposed residential
construction are provided herein, as well as foundation design recommendations based on the as-graded soil
conditions,
The purpose of grading was to develop two (2) pads for construction of single family residences, The proposed
residential structures will be either one- or two-story structures with wood or steel-framed construction, Grading on
the subject pads began on April 29, 2004 and was completed on May 19, 2004,
1.0
REGULATORY COMPLIANCE
Removal and recompaction oflow-density surface soils, processing of the exposed bottom surfaces or placement of
compacted fill under the purview ofthis report have been completed under the observation and with selective testing
by LGC, Earthwork and grading operations were performed in accordance with the recommendations presented in
the referenced reports (see References) and the grading code ofthe City of Temecula, California, The completed
earthwork has been reviewed and is considered adequate for the construction now planned, On the basis of our
observations and field and laboratory testing, the recommendations presented in this report were prepared in
conformance with generally accepted professional engineering practices and no further warranty is expressed or
implied,
1
140935 County Center Drive' Suite A' Temecula, CA 92591 . (951) 719-1076 ' Fax (951) 719-1077
.'.
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2.0 ENGINEERING GEOLOGY
2.1 General
Geologic conditions exposed during the process of grading were frequently observed and mapped by LGC's
geologic staff. '
2.2 Geolo/de Units
Earth materials within the site included Quaternary alluvium and Pauba Formation sandstone,
2.3 Groundwater
During overexcavations, no free groundwater was encountered.
2.4 Faultinll
No faults were observed during grading operations on the site.
3.0 SUMMARY OF EARTHWORK OBSERVATIONS AND DENSITY TESTING
3.1 Site Clearinll and Grubbinll
Prior to grading, all grasses and weeds were stripped and removed form the site.
3.2 Ground Preparation
The proposed building pad in Parcel 2 is located in a "cut/fill" transition in order to obtain final pad grade,
The Parcel 3 building pad is entirely in "cut". All deposits of existing low density native soils (alluvial silty
sands/clayey sands) were removed to firm, competent bedrock materials over the "fill" portion of the
building pad, including a minimum of 5 feet beyond the building perimeter. Overexcavation was required in
order to eliminate the cut/fill transition, The cut/fill transition was eliminated by overexcavating the cut area
and constructing a compacted fill with a minimum thickness of 10* feet.
Prior to placing fill, the exposed bottom surfaces were scarified to depths of 6 to 8 inches, watered or air-
dried as necessary to achieve at or slightly above optimum moisture content and then recompacted in-place
to a minimum relative compaction of90 percent. Moisture conditions at the exposed depths were generally
below optimum moisture content.
3.3 Disposal of Oversize Roek
Oversize rock (rock generally greater than I foot in maximum dimension) was not encountered during the
removal operations.
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Project No, 104470-30
Page 2
August 17, 2004
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3.4 Fill Placement and Testinf!
Fill materials consist of onsite soils, All fills were placed in lifts restricted to approximately 6 to 8 inches in
maximum thickness, watered or air dried as necessary to achieve near optimum moisture conditions, then
compacted in-place to a minimum relative compaction of 90 percent by rolling with an 834 rubber-tired
bulldozer or loaded scrapers, The maximum vertical depth of fill placed within the subject pads as a result
of grading is approximately 28 feet in Parcel 2.
Field density and moisture content tests were performed in accordance with ASTM Test Methods D2922 and
D30l7 (nuclear gauge), Test results are presented on Table I (attached) and test locations are shown on the
enclosed Density Test Location Map (Plate I),
Field density tests were taken at vertical intervals of approximately I to 2 feet and the compacted fills were
tested at the time of placement to verifY that the specified moisture content and minimum required relative
compaction of90 percent had been achieved, At least one in-place density test was taken for each 1,000
cubic yards of fill placed and/or for each 2 feet in vertical height of compacted fill, The actual number of
tests taken per day varied with the project conditions, such as the number of earthmovers (scrapers) and
availability of support equipment. When field density tests produced results less than the required minimum
relative compaction of 90 percent, the approximate limits of the substandard fill were established, The
substandard area was then reworked, moisture conditioned, re-compacted, and retested until the minimum
relative density was achieved,
Visual classification of earth materials in the field was the basis for determining which maximum dry density
value, summarized in Appendix A, was applicable for a given density test. One-point checks were
periodically performed to supplement visual classification.
3.5 Slooes
Fill slopes constructed within the subject site consisted of medium height 2: I horizontal to vertical (h:v) to
a maximum height of20olo feet. Prior to constructing the fill slopes, typical "'fill keys" were incorporated a
minimum of2 feet into the underlying bedrock as part ofthe remedial removal and recompaction operations,
Medium height 2: 1 (h:v) cut slopes varying to a maximum height of 2Qr feet were built as a result of
constructing the cut area within the building pad, The cut slope between Parcels 2 and 3 exposed clean sands
ofthe Pauba formation on at least one-third of the slope, This sand unit is easily erodable, LGC recommends
that some means of slope protection be afforded for this slope, either by constructing a "stability fill" at the
slope face or providing vegetative cover, '
4.0 LABORATORY TESTING
4.1 Maximum Drv Densitv
Maximum dry density and optimum moisture content for the major soil types observed during grading were
determined in our laboratory in accordance with ASTM Test Method D1557-00, Pertinent test values are
summarized in Appendix B.
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Project No. 104470-30 ;~
Page 3
August f 7. 2004
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4,2 Expansion Index Tests
Expansion index tests were performed on representative samples of soil existing at or near finish pad grade
within the subject pads, These tests were performed in accordance with ASTM 04829 Standard 18-2, Test
results are summarized in Appendix B.
4.3 Soluble Sulfate Analvses
Water soluble sulfate contents were also determined for representative sanlples of soil existing at or near pad
grade of the subject pads in accordance with California Test Method No. 417. These tests resulted in
negligible sulfate contents of less than 0,1 percent. Test results are summarized in Appendix B, .
5.0 POST GRADING CONSIDERA TIONS
5.1 Landscapinf! and Maintenance of Graded Slopes
The fill and/or cut slopes within the subject areas vary up to a maximum height ofless than 20x feet. Unless
long term mitigation measures are taken, the slopes may be subject to a low to moderate degree of surficial
erosion or degradation during periods of heavy rainfall, especially the cut slope between Parcels 2 and 3,
Therefore, it is recommended that the slopes be landscaped with a deep rooted, drought resistant, woody
plant species, To provide temporary slope protection while the woody materials mature, the slopes should
be planted with an herbaceous plant species that will mature in one season or provided with some other
protection, such as jute matting or polymer covering. The temporary protection should be maintained until
the woody material has become fully mature, A landscape architect should be consulted to determine the
most suitable plant materials and irrigation requirements,
To mitigate future surficial erosion and slumping, a permanent slope maintenance program should be
initiated, Proper slope maintenance must include regular care of drainage and erosion control provisions,
rodent control, prompt repair ofleaking irrigation systems and replacement of dying or dead plant materials,
The irrigation system should be designed and maintained to provide constant moisture content in the soils,
Over watering, as well as over drying, of the soils can lead to surficial erosion and/or slope deterioration.
The owners should be advised of the potential problems that can develop when drainage on their pads and
adjacent slopes is altered in any way, Drainage can be adversely altered due to the placement of fill and
construction of garden walls, retaining walls, walkways, patios, swimming pools and planters.
5.2 Pad Drainaf!e
Drainage on the pads should be designed to carry surface water away from all graded slopes and structures,
Pad drainage should be designed for a minimum gradient of I percent with drainage directed to the adjacent
streets, After dwellings are constructed, positive drainage away from the structures and slopes should be
provided on the lots by means of earth swales, sloped concrete flatwork and area drains.
5.3 Utility Trenches
All utility trench backfill within street right-of-ways, utility easements, under sidewalks, driveways and
building floor slabs and within or in proximity to slopes, should be compacted to a minimum relative
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compaction of 90 percent. Where onsite soils are utilized as backfill, mechanical compaction will be
required, Density testing, along with probing, should be performed by a LGC representative to verifY
adequate compaction, Excavations for trenches that exceed 4 feet in depth should be laid-back at a
maximum gradient of 1: I (h:v),
For deep trenches with vertical walls, backfills should be placed in lifts no greater than 2 feet in thickness
and then mechanically compacted with a hydra-hammer, pneumatic tampers or similar equipment. For deep
trenches with sloped walls, backfill matelials should be placed in lifts no greater than 8 inches and then
compacted by rolling with a sheepsfoot tamper or similar equipment.
As an alternative for shallow trenches (18 inches or less in depth) where pipe may be damaged by
mechanical compaction equipment, such as under building-floor slabs, imported clean sand having a sand
equivalent of30 or greater may be utilized and jetted or flooded into place, No specific relative compaction
will be required; however, observation, probing and, if deemed necessary, testing should be performed,
To avoid point loads and subsequent distress to clay, cement, or plastic pipe, sand bedding should be placed
at least I-foot above all pipe in areas where excavated trench materials contain significant cobbles. Sand
bedding materials should be thoroughly jetted prior to placement of backfill.
Where utility trenches are proposed parallel to any building footing (interior and/or exterior trenches), the
bottom of the trench should not be located within a 1:1 (h:v) plane projected downward from the outside
bottom edge of the adjacent footing,
6.0 FOUNDATION DESIGN RECOMMENDA TIONS
6.1 General
Conventional shallow foundations are considered feasible for support of the proposed residential structures,
Foundation recommendations are provided herein,
6.2 Allowable Bearinf! Values
An allowable bearing value of 1,500 pounds per square foot (pst) is recommended for design of24-inch
square pad footings and 12-inch wide continuous footings founded at a minimum depth of 12 inches below
the lowest adjacent final grade, This value may be increased by 20 percent for each additional I-foot of
width and/or depth to a maximum value of2,500 psf, Recommended allowable bearing values include both
dead and live loads and may be increased by one-third when designing for short duration wind and seismic
forces,
6.3 Settlement
Based on the general settlement characteristics of the soil types that underlie the building sites and the
anticipated loading, it has been estimated that the maximum total settlement of conventional footings will be
less than approximately ~-inch. Differential settlement is expected to be about y,-inch over a horizontal
distance of approximately 20 feet, for an angular distortion ratio of I :480, It is anticipated that the majority
of the settlement will occur during construction or shortly thereafter as building loads are applied,
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The above settlement estimates are based on the assumption that the project geotechnical consultant will
observe or test the soil conditions in the footing excavations,
6.4 Lateral Resistance
A passive earth pressure of 250 psf per foot of depth to a maximum value of 2,500 psf may be used to
determine lateral bearing resistance for footings, Where structures are planned in or near descending slopes,
the passive earth pressure should be reduced to 150 psf per foot of depth to a maximum value of 1,500 psf,
In addition, a coefficient of friction of 0.40 times the dead load forces may be used between concrete and the
supporting soils to determine lateral sliding resistance, The above values may be increased by one-third
when designing for short duration wind or seismic forces,
The above values are based on footings placed directly against compacted fill or bedrock, In the case where
footing sides are formed, all backfill placed against the footings should be compacted to a minimum of90
percent of maximum dry density,
,6.5 FootinI! Observations
All foundation excavations should be observed by the project geotechnical engineer to verifY that they have
been excavated into competent bearing soils, The foundation excavations should be observed prior to the
placement of forms, reinforcement or concrete. The excavations should be trimmed neat, level and square,
All loose, sloughed or moisture softened soil should be removed prior to concrete placement.
Excavated materials from footing excavations should not be placed in slab on grade areas unless the soils are
compacted to a minimum 90 percent of maximum dry density,
6.6 Expansive Soil Considerations
Results ofthe laboratory tests indicate onsite soil and bedrock materials exhibit expansion potentials ranging
from VERY LOW to LOW as classified in accordance with 1997 UBe Table l8-1-B. The design and
construction details herein are intended to provide recommendations for the various levels of expansion
potential.
A pad by pad breakdown for different levels of expansion potential is provided below:
Very Low Expansion Potential- Parcel 3,
. Low Expansion Potential ~ Parcel 2,
6.6.1 Verv Low Exoansion Potential (Exoansion Index of 20 or Less)
Results of our laboratory tests indicate onsite soils (Parcel 3) exhibit a VERY LOW expansion
potential as classified in accordance with Table 18-1-B of the 1997 Uniform Building Code (UBC),
..', Since the onsite soils exhibit expansion indices of less than 20, the design of slab on ground
foundations is exempt from the procedures outlined in Section 1815, Based on the above soil
conditions, it is recommended that footings and floors be constructed and reinforced in accordance
with the following minimum criteria, However, additional slab thickness, footing sizes and/or
reinforcement should be provided as required by the project architect or structural engineer.
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6.6.1.1 Footinlls
. Exterior continuous footings may be founded at the minimum depths indicated in UBC Table
18-I-C (i.e, 12-inch minimum depth for one-story and 18-inch minimum depth for two-story
construction). Interior continuous footings for both one- and two-story construction may be
founded at a minimum depth of 12 inches below the lowest adjacent grade, All continuous
footings should have a minimum width of 12 and 15 inches, for one-story and two-story
buildings, respectively, and should be reinforced with two (2) No.4 bars, one (1) top and
one (I) bottom,
. Exterior pad footings intended for the support of roof overhangs, such as second story decks,
patio covers and similar construction should be a minimum of24 inches square and founded
at a minimum depth of 18 inches below the lowest adjacent final grade, No special
reinforcement of the pad footings will be required,
6.6.1.2 Bui/dinll Floor Slabs
. Concrete floor slabs should be 4 inches thick and reinforced with either 6-inch by 6-inch,
No, 6 byNo. 6 welded wire mesh (6x6-W2,9xW2.9); or with No, 3 bars spaced a maximum
of24 inches on center, both ways, All slab reinforcement should be supported on concrete
chairs or bricks to ensure the desired placement near mid-depth,
. Concrete floor slabs should be underlain with a moisture vapor barrier consisting of a
polyvinyl chloride membrane such as 6-mil visqueen, or equivalent. All laps within the
membrane should be sealed, and at least 2 inches of clean sand be placed over the membrane
to promote uniform curing of the concrete,
. Garage area floor slabs should be 4 inches thick and should be reinforced in a similar manner
as living-area floor slabs, Garage area floor slabs should also be placed separately from
adjacent wall footings with a positive separation maintained with Yo-inch minimum felt
expansion joint materials and quartered with weakened plane joints, A l2-inch wide grade
beam founded at the same depth as adjacent footings should be provided across garage
entrances, The grade beam should be reinforced with a minimum oftwo (2) No, 4 bars, one
(I) top and one ( I) bottom,
. Prior to placing concrete, the sub grade soils below all living area and garage area floor slabs
should be pre-watered to promote uniform curing of the concrete and minimize the
development of shrinkage cracks,
6.6.2 Low Exoansion Potential (Exoansion Index 0(21 to 50)
Results of our laboratory tests indicate onsite soils (Parcel 2) exhibit a LOW expansion potential as
classified in accordance with Table l8-I-B of the 1997 Uniform Building Code (UBC). The 1997
UBC specifies that slab on ground foundations (floor slabs) resting on soils with expansion indices
greater than 20, require special design considerations in accordance with 1997 UBC Section 1815,
The design procedures outlined in 1997 UBC Section 1815 are based on the thickness and plasticity
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index of each different soil type existing within the upper 15 feet of the building site, For final
design purposes, we have assumed an effective plasticity index of 12 in accordance with 1997 UBC
Section 1815.4,2,
6.6.2.1 Footinfls
. Exterior continuous footings may be founded at the minimum depths indicated in UBC Table
18-r-C (i,e, 12-inch minimum depth for one-story and 18-inch minimum depth for two-story
construction), Interior continuous footings for both one- and two-story construction may be
founded at a minimum depth of 12 inches below the lowest adjacent grade. All continuous
footings should have a minimum width of 12 and 15 inches, for one-story and two-story
buildings, respectively, and should be reinforced with two (2) No, 4 bars, one (1) top and
one (l) bottom,
. Exterior pad footings intended for the support of roof overhangs, such as second story decks,
patio covers and similar construction should be a minimum of24 inches square and founded
at a minimum depth of 18 inches below the lowest adjacent final grade, The pad footings
should be reinforced with No.4 bars spaced a maximum of 18 inches on center, both ways,
near the bottom-third of the footings.
6.6.2.2 Buildinfl Floor Slabs
. The project architect or structural engineer should evaluate minimum floor slab thickness
and reinforcement in accordance with 1997 UBC Section 1815 based on an effective
plasticity index of 12. Unless a more stringent design is recommended by the architect or
the structural engineer, we recommend a minimum slab thickness of 4 inches for both living
area and garage floor slabs, and be reinforced with either 6-inch by 6-inch, No, 6 by No, 6
welded wire mesh (6x6-W2.9xW2,9); or with No.3 bars spaced a maximum of24 inches on
center, both ways, All slab reinforcement should be supported on concrete chairs or bricks
to ensure the desired placement near mid-depth, Hooking of reinforcement is not an
acceptable method of positioning,
. Concrete floor slabs should be underlain with a moisture vapor barrier consisting of a
polyvinyl chloride membrane such as 6-mil visqueen, or equivalent. All laps within the
membrane should be sealed, and at least 2 inches of clean sand be placed over the membrane
to promote uniform curing of the concrete,
. Garage floor slabs should be 4 inch,es thick and should be reinforced in a similar manner as
living area floor slabs. Garage floor slabs should also be placed separately from adjacent
wall footings with a positive separation maintained with %-inch minimum felt expansion
joint materials and quartered with weakened plane joints. A 12-inch wide grade beam
founded at the same depth as adjacent footings should be provided across garage entrances,
The grade beam should be reinforced with a minimum oftwo (2) No, 4 bars, one (I) top and
one (1) bottom,
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. Prior to placing concrete, the subgrade soils below all living area and garage floor slabs
should be pre-watered to achieve a moisture content that is at least equal or slightly greater
than optimum moisture content. This moisture content should penetrate to a minimum depth
of 12 inches into the sub grade soils,
6.7 Post Tensioned Slab/Foundation Desi!m Recommendations
In lieu of the proceeding recommendations for conventional footing and floor slabs, post tensioned slabs
may be utilized for the support of the proposed residential structures, We recommend that the foundation
engineer design the foundation system using the geotechnical parameters provided in Table I. These
parameters have been determined in general accordance with Chapter 18 Section 1816 of the Uniform
Building Code (UBC), 1997 edition. Alternate designs are allowed per 1997 UBC Section 1806,2 that
addresses the effects of expansive soils when present. In utilizing these parameters, the foundation engineer
should design the foundation system in accordance with the allowable deflection criteria of applicable codes
and the requirements ofthe structural engineer/architect.
Please note that the post tensioned design methodology reflected in UBC Chapter 18 is in part based on the
assumption that soil moisture changes around and beneath the post tensioned slabs are influenced only by
climatological conditions, Soil-moisture change below slabs is the major factor in foundation damages
relating to expansive soil. The UBC design methodology has no consideration for presaturation, homeowner
irrigation, or other nonclimate related influences on the moisture content of subgrade soils, In recognition of
these factors, we have modified the geotechnical parameters obtained from this methodology to account for
reasonable irrigation practices and proper homeowner maintenance, In addition, we recommend that prior to
foundation construction, slab sub grades be presoaked to 12 inches prior to trenching and maintained at above
optimum moisture up to concrete construction. We further recommend that the moisture content of the soil
around the immediate perimeter of the slab be maintained at near optimum-moisture content (or above)
during construction and up to occupancy of the homes.
The geotechnical parameters provided in the following table assume that if the areas adjacent to the
foundation are planted and irrigated, these areas will be designed with proper drainage so ponding, which
causes significant moisture change below the foundation, does not occur. Our recommendations do not
account for excessive irrigation and/or incorrect landscape design. Sunken planters placed adjacent to the
foundation, should either be designed with an efficient drainage system or liners to prevent moisture
infiltration below the foundation, Some lifting of the perimeter foundation beam should be expected even
with properly constructed planters, Based on the design parameters we have provided, and our experience
with monitoring similar sites on these types of soils, we anticipate that if the soils become saturated below
the perimeter of the foundations due to incorrect landscaping irrigation or maintenance, then up to
approximately \12- to I-inch of uplift could occur at the perimeter of the foundation relative to the central
portion of the slab,
Future homeowners should be informed and educated regarding the importance of maintaining a constant
level of soil moisture. The owners should be made aware of the potential negative consequences of both
excessive watering, as well as allowing expansive soils to become too dry, The soil will undergo shrinkage
as it dries up, followed by swelling during the rainy winter season, or when irrigation is resumed, This will
result in distress to the improvements and structures.'
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Preliminarv Geotechnical Parameters for Post Tensioned Foundation Slab Des;,m
PARAMETER VALUE ,
Exoansion Index Very Low Low
Percent that is Finer than 0.002 nun in the Fraction Passing the < 20 percent < 20 percent
No, 200 Sieve, (assumed) (assumed)
Clay Mineral Type Montmorillonite Montmorillonite
(assumed) (assumed)
Thomthwaite Moisture Index .20 .20
Depth to Constant Soil Suction (estimated as the depth to 7 feet 7 feet
constant moisture content over time, but within U,B.C.limits)
Constant Soil Suction P,F.3.6 P.F,3,6
Moisture Velocity 0,7 inches/month 0,7 inches/month
Center Lift Edge moisture variation distance, em 4.6 reet 4,6 teet
Center lift, Ym 1.4 inches 1.4 inches
Edge Lift Edge moisture variation distance, em 2,2 feet 2.2 reet
Edge lift, Ym 0.4 inches 0.4 inches
Soluble Sulfate Content for Design of Concrete Mixtures in
Contact with Site Soils in Accordance with 1997 UBC Table Negligible Negligible
19.A.4
Modulus of Subgrade Reaction, k (assuming presaturation as 200 pci 200 pci
indicated below)
Minimum Perimeter Foundation Embedment 12 12
Additional Recommendations:
Presoak to 12 inches prior to trenching, maintain at above optimum up to concrete construction,
Install a 6-mil Visqueen (or equivalent) moisture barrier covered by a minimum of I-inch layer of sand and 2 inches
below. Or, installlO.mil Visqueen (or equivalent) moisture barrier in contact with the native soils and covered by a
minimum of at least 2 inches of sand. Note: For both options, the builder must ensure that the Visqueen has been lapped
and sealed and not punctured as a result of being placed in direct contact with the native soils or by other construction
methods. ·
* The above sand and Visqueen recommendations are traditionally included with geotechnical foundation
recommendations although they are generally not a major factor influencing the geotechnical performance of the
foundation. The sand and Visqueen requirements are the purview of the foundation engineer/corrosion engineer and the
homebuilder to ensure that the concrete cures correctly is protected from corrosive envirorunents and moisture penetration
of the floor is acceptable to the future homeowners. Therefore, the above recommendations may be superseded by the
requirements of the previously mentioned parties,
6.8
Corrosivitv to Concrete and Metal
The National Association of Corrosion Engineers (NACE) defines corrosion as "a deterioration of a
substance or its properties because of a reaction with its environment." From a geotechnical viewpoint, the
"environment" is the prevailing foundation soils and the "substances" are the reinforced concrete
foundations or various buried metallic elements such as rebar, piles, pipes, etc., which are in direct contact
with or within close vicinity of the foundation soil.
In general, soil environments that are detrimental to concrete have high concentrations of soluble sulfates
and/or pH values ofless ihan 5.5. Table 19-A-4 of the U.B.C" 1997, provides specific guidelines for the
concrete mix design when the soluble sulfate content of the soils exceeds 0.1 percent by weight or 1 ,000
ppm,
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Based on testing performed within the project area, the onsite soils are classified as having a negligible
sulfate exposure condition in accordance with Table 19-A-4 ofU,B.C., 1997, Therefore, in accordance with
Table 19-A-4 structural concrete in contact with earth materials should have cement of Type lor II.
Despite the minimum recommendation above, LGC is not a corrosion engineer, therefore, we recommend
that you consult with a competent corrosion engineer and conduct additional testing (if required) to evaluate
the actual corrosion potential of the site and provide recommendations to mitigate the corrosion potential
with respect to the proposed improvements. The recommendations ofthe corrosion engineer may supersede
the above requirements.
6.9 Structural Setbacks
Structural setbacks in addition to those required in the UBC, are not required due to geologic or geotechnical
conditions within the site, Building setbacks from slopes, property lines, etc, should conform to 1997 UBC
requirements,
7.0 RETAINING WALLS
7.1 Active and At-Rest Earth Pressures
For Parcel 3, an active earth-pressure represented by an equivalent fluid having a density of35 pounds per
cubic foot (pct) should tentatively be used for design of cantilevered walls up to 10 feet high retaining a
drained level backfill. Where the wall backfill slopes upward at 2; I (h:v), the above value should be
increased to 52 pcf. All retaining walls should be designed to resist any surcharge loads imposed by other
nearby walls or structures in addition to the above active earth pressures.
For design of retaining walls up to 10 feet high that are restrained at the top, an at-rest earth pressure
equivalent to a fluid having a density of 53 pcf should tentatively be used for walls supporting a level
backfill. This value should be increased to 78 pcffor ascending 2:1 (h:v) backtlll.
For Parcel 2, an active earth-pressure represented by an equivalent fluid having a density of 40 pcf should
tentatively be used for design of cantilevere~ walls up to 10 feet high retaining a drained level backfill.
Where the wall backfill slopes upward at 2:1 (h:v), the above value should be increased to 63 pcf. All
retaining walls should be designed to resist any surcharge loads imposed by other nearby walls or structures
in addition to the above active earth pressures.
For design of retaining walls up to 10 feet high that are restrained at the top, an at-rest earth pressure
equivalent to a fluid having a density of 60 pcf should tentatively be used for walls supporting a level
backfill. This value should be increased to 95 pcf for ascending 2; I (h:v) backfill.
'7.2 Drainal!e
Weep holes or open vertical masonry joints should be provided in retaining walls to prevent entrapment of
water in the backfill. Weep holes, if used, should be 3 inches in minimum diameter and provided at
minimum intervals of 6 feet along the wall. Open vertical masonry joints, if used, should be provided at
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32-inch minimum intervals, A continuous gravel fill, 12 inches by 12 inches, should be placed behind the
weep holes or open masonry joints, The gravel should be wrapped in filter fabric to prevent infiltration of
fines and subsequent clogging of the gravel. Filter fabric may consist of Mirafi 140N or equivalent.
In lieu of weep holes or open joints, a perforated pipe-and-gravel subdrain may be used, Perforated pipe
should consist of 4-inch minimum diameter PVC Schedule 40 or ASS SDR-35, with the perforations laid
down. The pipe should be embedded in I y, cubic feet per foot of 1.0- or I y,-inch open graded gravel
wrapped in filter fabric. Filter fabric may consist of Mirafi 140N or equivalent.
The backfilled side of the retaining wall supporting backfill should be coated with an approved
waterproofing compound to inhibit infiltration of moisture through the walls,
7.3 Temporarv Excavations
All excavations should be made in accordance with OSHA requirements, LGC is not responsible for job site
safety,
7.4 Wall Backfill
All retaining-wall backfill should be placed in 6- to 8-inch maximum lifts, watered or air dried as necessary
to achieve near optimum moisture conditions and compacted in place to a minimum relative compaction of
90 percent.
8.0 MASONRY GARDEN WALLS
Footings for masonry garden walls should also be reinforced with a minimum offour (4) No, 4 bars, two (2) top and
two (2) bottom, In order to mitigate the potential for unsightly cracking, positive separations should also be
provided in the garden walls at a maximum horizontal spacing of20 feet. These separations should be provided in
the blocks only and not extend through the footing, The footing should be placed monolithically with continuous
rebars to serve as an effective "grade beam" below the wall.
In areas where garden walls may be proposed on or near the tops of descending slopes, the footings should be
deepened such that a minimum horizontal clearance of5 feet is maintained between the outside bottom edges of the
footings and the face of the slope,
9.0 CONCRETE FLATWORK
9.1 Thickness and Joint Spacinr!
II
To reduce the potential of unsightly cracking, concrete sidewalks and patio type slabs should be at least 3 \12
inches thick and provided with construction or expansion joints every 6 feet or less, Any concrete driveway
slabs should be at least 4 inches thick and provided with construction or expansion joints every 10 feet or
less.
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9.2 Subf!rade Preparation
As a further measure to minimize cracking of concrete flatwork, the subgrade soils underlying concrete
flatwork should first be compacted to a minimum relative compaction of90 percent and then thoroughly
wetted to achieve a moisture content that is at least equal to or slightly greater than optimum moisture
content. This moisture should extend to a depth of 12 inches below subgrade and be maintained in the soils
during the placement of concrete. Pre-watering of the soils will promote uniform curing of the concrete and
minimize the development of shrinkage cracks, A representative of the project geotechnical engineer should
observe and verifY the density and moisture content of the soils and the depth of moisture penetration prior
to placing concrete,
9.3 Drainaf!e
Drainage from patios and other flatwork areas should be directed to local area drains and/or graded-earth
swales designed to carry runoff water to the adjacent streets or other approved drainage structure, The
concrete flatwork should also be sloped at a minimum gradient of I percent away from building foundations,
retaining walls, masonry garden walls and slopes,
9.4 Tree Wells
Tree wells are not recommended in concrete- flatwork areas since they can introduce excessive water into the
subgrade soils or allow for root invasion, both of which can result in uplift of the flatwork.
10.0 PLANTERS AND PLANTER WALLS AND LANDSCAPING
10.1 Planters
Planters that are located within 5 feet of building foundations, retaining walls, masonry garden walls and
slope areas should be provided with either sealed bottoms or bottom drains to prevent infiltration of water
into the adjacent foundation soils. The surface of the ground in these areas should also be maintained at a
minimum gradient of2 percent and direct drainage to area drains or earth swales,
Planters adjacent to a building or structure should be avoided wherever possible or be properly designed
(e,g., lined with a membrane), to reduce the penetration of water into the adjacent footing subgrades and
thereby reduce moisture related damage to the foundation, Planting areas at grade should be provided with
appropriate positive drainage. Wherever possible, exposed soil areas should be above adjacent paved grades
to facilitate drainage, Planters should not be depressed below adjacent paved grades unless provisions for
drainage, such as multiple depressed area drains are constructed, Adequate drainage gradients, devices, and
curbing should be provided to prevent runoff from adjacent pavement or walks into planting areas, Irrigation
methods should promote uniformity of moisture in planters and beneath adjacent concrete flatwork, Over
watering and under watering of landscape areas must be avoided,
10.2 Planter Walls
Low height planter walls should be supported by continuous concrete footings constructed in accordance
with the recommendations presented for masonry block wall footings,
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10.3 Landscaoinl!
In recognition that the future homeowners will add either soft scape or hard scape after precise grading, the
following recommendations may be used as a guide, [t is paramount that future homeowners consult with a
professional engineer to ensure that the construction of future landscaping improvements will not cause
obstruction of existing drainage patterns or does not cause surface water to collect adjacent to the
foundation, creating saturated soils adjacent to the foundation,
Area drains should be maintained and kept clear of debris in order to properly function. Homeowners should
also be made aware that excessive irrigation of neighboring properties can cause seepage and moisture
conditions on adjacent lots. Homeowners should be furnished with these recommendations communicating
the importance of maintaining positive drainage away from structures towards streets when they design their
improvements.
The impact of heavy irrigation or inadequate runoff gradients can create perched water conditions, This may
result in seepage or shallow groundwater conditions where previously none existed, Maintaining adequate
surface drainage and controlled irrigation will significantly reduce the potential for nuisance type moisture
problems. To reduce differential earth movements such as heaving and shrinkage due to the change in
moisture content of foundation soils, which may cause distress to a residential structure and associated
improvements, moisture content ofthe soils surrounding the structure should be kept as relatively constant as
possible.
10.4 Swimminl! Pools and Soas
No pools or spas are shown on the plans. In general, due to the presence of soils with low expansion
potential, LGC does not recommend pools or spas be located within 15 feet of the top of2: I (h:v) slopes
without special foundation design considerations. While expansi ve soil related cracking of concrete flatwork
and garden walls may only be cosmetic in nature, and thus tolerable, such cracking in pools and/or spas
cannot be tolerated, Soil expansion forces should be taken into account for design and construction of a
swimming pool and/or spa,
For soils having a VERY LOW and LOW expansion potential, we recommend a lateral earth pressure of
78 pcfbe used for design of pools/spa shells,
To avoid localized saturation of soils, landscaping of the backyard should not be planned with unlined
planter boxes in the immediate vicinity of the pool/spa shell.
The excavated material from the pool/spa area is often used to build elevated planter boxes and/or other
structures adjacent to the pool area, This practice imposes significant loads at the location of these structures
and induces differential settlements, This practice could jeopardize the integrity of the pool/spa and possibly
other improvements. Pool decking should also receive special design considerations, since the pool is
founded generally 5 to 6 feet below grade. If pool decking is not correctly designed for expansive soils,
differential movement between the flatwork imd pool will occur. A geotechnical consultant should be
retained to evaluate the impact of planned improvements and provide proper recommendations for design,
Whether the pool/spa shell is in the zone ofintluence of the building or wall footing, the need for shoring or
support for the building or wall footing should also be taken into consideration.
7.0
Project No, [04470-30
Page 14
August 17, 2004
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11.0 POST GRADING OBSERVATIONS AND TESTING
LGC should be notified at the appropriate times in order to provide the following observation and testing services
during the various phases of post-grading construction.
11.1 Bui/dinf! Construction
. Observe all footings when first excavated to verify adequate depth and competent soil bearing
conditions,
Re-observe all footings, if necessary, if trenches are found to be excavated to inadequate depth and/or
found to contain significant slough, saturated or compressible soils.
11.2 Retaininf! Wall Construction
Observe all footing trenches when first excavated to verifY adequate depth and competent soil bearing
conditions,
Re-observe all footing trenches, if necessary, if trenches are found to be excavated to inadequate depth
and/or found to contain significant slough, saturated or compressible soils,
. Observe and verifY proper installation of subdrain systems prior to placing wall backfill.
. Observe and test placement of all wall backfill.
11.3 Masonrv Garden Walls
Observe all footing trenches when first excavated to verifY adequate depth and competent soil bearing
conditions,
Re-observe all footing trenches following removal of any slough and/or saturated soils and re-excavate
to proper depth.
11.4 Exterior Concrete Flatwork Construction
. Observe and test subgrade soils below all concrete tlatwork areas to verify adequate compaction and
moisture content.
11. 5 Utility- Trench Backfill
. Observe and test placement of all utility trench backfill.
11.6 Re-Gradinf!
. Observe and test placement of any fill to be placed above or beyond the finish grades shown on the
grading plans,
'2..\
Project No. 104470-30
Page 15
August 17. 2004
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12.0 LIMITATIONS
Our services were performed using the degree of care and skill ordinarily exercised, under similar circumstances, by
reputable engineers and geologists practicing in this or similar localities. No other warranty, expressed or implied, is
made as to the conclusions and professional advice included in this report,
This report is issued with the understanding that it is the responsibility of the owner, or of his/her representative, to
ensure that the information and recommendations contained herein are brought to the attention of the architect
and/or project engineer and incorporated into the plans, and the necessary steps are taken to see that the contractor
and/or subcontractor properly implements the recommendations in the field, The contractor and/or subcontractor
should notify the owner if they consider any of the recommendations presented herein to be unsafe,
The findings of this report are valid as of the present date, However, changes in the conditions of a property can and
do occur with the passage of time, whether they be due to natural processes or the works of man on this or adjacent
properties.
In addition, changes in applicable or appropriate standards may occur, whether they result from legislation or the
broadening of knowledge , Accordingly, the findings of this report may be invalidated wholly or partially by changes
outside our control. Therefore, this report is subject to review and modification, and should not be relied upon after a
period of 3 years,
The opportUnity to be of service is appreciated, Should you have any questions regarding the content of this report,
or should you require additional information, please do not hesitate to contact this office at your earliest
convemence.
LGC INLAND, INC.
Respectfully submitted,
Stephen M, Poole
Vice President
Principal Engineer, GE 692
Chad E, Welke
Associate Geologist/Engineer, RG 7341, RCE 63712
GEU/CW/SMP/jn
Attachments: Table I - Summary ofField Density Tests (Rear of Text)
Appendix A - Laboratory Test Criteria/Laboratory Test Data (Rear of Text)
Plate I - Density Test Location Map (In Pocket)
Distribution: (4) Addressee
2Z-
Project No, 104470-30
Page 16
August 17. 2004
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TABLE I
SUMMARY OF FIELD DENSITY TESTS
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TABLE I
Parcels 2 and 3 of
Parce/Map 12887
I
SUMMARY OF FIELD DENSITY TESTS
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-~~~ -
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I N~ 04/29/04 CF YardArea,HousePad 1107 I 121.3' 10,7 92
2 N 04/29/04 CF Yard Area. House Pad 1\09 I 122.4 1\.4 9:\
3 N 05/03/04 CF Yal'ct Area - House Pad 1100 I 120.4 10,9 91
4 N 05/04/04 CF Yard Area - House Pad 1105 I 120.9 11.5 92
5 N 05/04/04 CF N/W House Pad 108~\ I 119.4 9.4 91
G N 05/04/04 CF N/W House I'ad 1087 I 120,8 11.2 92
7 N 05/04/04 CF Northerly House Pad 1102 I 115.4 9.5 87
8 N 05/04/04 CF Retest #7 - I 111.7 10.7 84
9 N 05/05/04 CF Retest #8 . I 118.9 10,2 90
10 N 05/05/04 CF Northerly Yard Area 1104 I 1\9,1 9.8 90
1\ N 05/05/04 NG SW Corner Gara~e/Driveway 1080 I 113,1 G.9 8G
12 N 05/05/04 CF SW Cornel' Parcel 2 1079 t 119,2 12.8 90
I" N 05/05/04 CF S W Corner Parcel 2 1082 I 119.5 10.9 90
.>
t4 N 05/0G/04 CF SW Corner Parcel 2 1090 1 119,7 12,1 90
15 N 05/0G/04 CF SW Corner 1084 2 104.8 14,:\ 92
IG N 05/0G/04 CF W House Pad 1088 2 108,9 IG.G 95
17 N 05/0G/04 CF Middle House Pad 1093 2 IOG,9 13.3 93
18 N 05/07/04 CF S House Pad Toe 1090 ? 103.0 14.2 90
19 N 05/07/04 CF S House Pad Toe 1093 2 10:U 14.7 91
20 N 05/08/04 CF SW House Pad 1095 2 114,7 15.6 91
21 N 05/08/04 CF W / Middle House Pad 1097 2 IOG.5 17.5 9"
,>
22 N 05/08/04 CF N/ Middle HOllse Pad 1099 2 103.4 15.4 90
2:~ N 05/08/04 CF S House Pad 1101 I 119.4 IO,G 91
24 N 05/08/04 CF SW HOllse Pad 1103 1 118.5 9.3 90
25 N 05/10/04 CF S House Pad 1105 2 103,9 13.8 91
26 N 05/10/04 CF S House Pad 1094 ~\ 115.8 10,2 90
27 N 05/10/04 CF SE House f'ad 1097 " IIG.:1 11.4 90
.>
2S N, 05/10/04 CI' S House Pad 1100 " 118,0 12,8 92
,>
29 N 05/10/04 CF Middle House Pad 1103 3 11 i.l 12.0 91
30 N 05/10/04 CF NW Yard Area House Pad 1107 3 118,7 12.9 92
31 N 05/ 1l/04 CI' SE House Pad 1109 3 IIG,O 10.1 90
32 N 05/11104 CF Middle House Pad 1105 :J IIG.:1 10.3 90
:1:J N 05/11104 CF Middle House Pad 1107 3 1l5,9 9.5 90
34 N 05/11/04 CF NE Real' Yard 1111 3 117,1 10.:\ 91
35 N 05/12/04 CF S House Pad 1107 <' 118.5 12.6 92
3G N 05/12/04 CF NE Real' Yard 1109 ., IIG.2 12,0 90
.>
37 N 05/13/04 CF NW House Pad 1109 I 119.7 9.6 91
38 N 05/13/04 CF SW House f'ad 1109 1 120.4 10,8 92
39 N 05/13/04 CF Middle House Pad 11 It 3 It7,S 11.4 92
40 N 05/13/04 CF SE House Pad Iltl 3 IIS.4 12,7 92
41 N 05/19/04 SF Parcel 2 slope 1104 I 119.2 8,8 91
42 N 05/19/04 SF Parcel 2 slope 1098 I 118.4 9,1 90
43 N 05/19/04 SF Parcel 2 slope tlO7 t 119.9 9.5 91
44 N 05/ t 9/04 CF House pad FG :1 ItG,7 10,3 91
45 N 05/19/04 CF House pad FG " 1l7.4 to.9 91
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4G N 05/19/04 CF House vad FG " 118.5 11.5 92
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N - Nuclear Gauge Test
NG - Natural Ground
CF- Compacted Fill
FG - FInish Grade
SF - Slope Face
Project No, [04470-30
Page I
August 17, 2004
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APPENDIX A
LABORATORY TESTING PROCEDURES AND TEST DATA
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APPENDIX A
, Laboratorv Testinf! Procedures and Test Results
The laboratory testing program was directed towards providing quantitative data relating to the relevant engineering
properties of the soils, Samples considered representative of site conditions were tested in general accordance with
American Society for Testing and Materials (ASTM) procedure and/or California Test Methods (CTM), where
applicable, The following summary is a brief outline of the test type and a tables summarizing the test results,
E.r:vansion Index: The expansion potential of selected samples was evaluated by the Expansion Index Test, ASTM
D4829, Specimens are molded under a given compacti ve energy to approximately the optimum moisture content and
approximately 50 percent saturation or approximately 90 percent relative compaction, The prepared I-inch-thick by 4-
inch-diameter specimens are loaded to an equivalent 144 psf surcharge and are inundated with tap water until
volumetric equilibrium is reached,
Maximum Densitv Tests: The maximum dry density and optimum moisture content of typical materials were
determined in accordance with ASTM DI557,
Soluble Sulfates: The soluble sulfate contents of selected samples were determined by standard geochemical methods
(CTM 417), The soluble sulfate content is used to determine the appropriate cement type and maximum water-cement
ratios, The test results are presented in the table below:
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TABLE A-I
Laboratorv Test Results
PARCEL NO. EXPANSION INDEX EXPANSION POTENTIAL
2 22 Low
3 0 Verv Low
TABLE A-2
Soluble Sulfate Test Results
,SAMPLE NO. PARCEL NO. SOLUBLE SULFATES, oom
I 2 II
2 3 ND
ND - None Detected
TABLE A-3
Maximum Density - Ovtimum Moisture Test Results
SAMPLE DESCRIPTION OPTIMUM MOISTURE, MAXIMUM DENSITY,
NUMBER (%) (pen
1 Olive brown silty fine to medium sand 9,0 131.5
with traces of gravel
2 Light oli ve brown fine sandy silt l4.0 114.5
3 Dark olive brown silty fine sand with 10.0 128.5
traces of gravel
""e,":. -"
Project No, /04470-30
Page 2
2-1
August /7, 2004
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