HomeMy WebLinkAboutCT 01-03; CALAVERA HILLS VILLAGE E-1; REPORT OF ROUGH GRADING; 2003-06-09Geotechnical 'Geologic. Environmental
5741 Palmer Way •. Carlsbad, California 92008 • '(760) 438-3155 • FAX (760)931-0915
June 9, 2003 '
W.0. 3459-B-SC
Calavera Hills II, LLC .;.
2727 Hoover Avenue
National City, California 91950
Attention Mr Don Mitchell
Subject: Report of Rough' Grading,'Calavera Hills, Village E-i, Lots '1through 28,
Carlsbad Tract 01-03, City of Carlsbad, San Diego County, California
Dear Mr. Mitchell
This report presents a summary of the geotechnical testing and observation services
provided by GeoSoils, Inc. (GSI), during the rough earthwork 'construction phase of
development at the subject site.' Earthwork commenced in February, 2003, and ,was
generally 'completed in May, 2003. This report does not include' utility and pavement
construction testing and observations. A report of observation and testing services for such
work will be provided under a separate cover.
PURPOSE OF EARTHWORK
The purpose of grading. was to prepare relatively level pads for the construction of
28 residential structures and access roadways. Cut-and-fill grading and drill'-and-shoot
blasting techniques were utilized to attain the desired graded configurations. Existing
topsoils and colluvium were removed to suitable bedrock material and recompacted. Cut
lots and the cut portion of transition lots were overexcavated in order to provide for more
uniform foundation support and/or to facilitate construction. Additionally, street areas were.
oyerexcavated to at least 1 foot below lowest utility import elevation to facilitate
improvement construction. The grading plans for this portion of Calavera Hills, Village E-1,'
prepared by Hunsaker & Associates Inc., San Diego, dated February 13,2003, are included
with this report as Plates 1 through 4
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. EARTH MATERIALS
Subsurface geologic, conditions exposed during the' process of rough grading Were
observed by a representative of GSI. Earth materials onsite generally. consist of dense
,
granitic/metavolcanic rock with a thin, discontinuous surficial veneer of topsoillcolluvium.
Dense surficial outcrops of granitic/volcanic bedrock were noted throughout the area:
GROUNDWATER
Naturally occurring groundwater was not encountered during rough grading of the building
Pads and should not affect the proposed building construction.. provided that the
recommendations contained in this report and/or provided by GSI are incorporated into final
design and construction, and that prudent surface and subsurface drainage practices are
incorporated into the construction plans. .
Based on the fractured and dense nature of the granitic/metavolcanic bedrocki perched
groundwater conditions may develop in the future due to excess irrigation, homeowner
altered drainage or damaged utilities, and should be anticipated. Should manifestations
of perched conditions (i.e., seepage) develop in the future, this office could assess the•
conditions and provide mitigative recommendations as necessary. A discussion of near
surface slope subdrainage is presented in our referenced report on toe drains (GSI, 1998d).
A discussion of other subdrainage is presented in a later section of this report
EARTHWORK CONSTRUCTION. . . .
Earthwork operations have been completed in general accordance with the City of Carlsbad
grading ordinance and the guidelines provided in the field by this office. . Observations
during grading included removals, overexcavation and subdrain construction along with
general grading procedures and placement of compacted fills by the contractor. . .
Rough Grading
Preparation of Existing. Ground .
Deleterious material, such as concentrated Organic matter and miscellaneous
debris, were stripped from the surface and disposed of beyond the limits of grading
for the subject area, prior to placing any fill. •. . .• . . ..
Loose surficial materials (i.e., existing topsoils, previously-placed fills, colluvium,
older alluvium and near surface paleosols) were removed to expose competent •
bedrock in all areas to receive fill. • . . . . . . . • . .
• In order to provide for more uniform support of structures, the cut portion of transition
lots were overexcavated to a minimum depth of 3 feet below pad grade, then
• brought to grade with compacted fill. Cut lots exposing dense granitic/vOlcanic rock
were overexcàvated a minimum of 3 feet below pad grade in order to facilitate
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foundation and utility construction Where possible, an attempt was made to slope
the overexcavated bottom toward the street area. Subdrainage of these areas does
not appear necessary at 'this time.
4. In order to facilitate utility construction, street areas exposing dense bedrock material
were overexcavated to at least 1 foot below lowest utility insert
.5. •. In areas where conventional cut-and-fill gradingtechniques were not feasible due'
to rock hardness, drill-and-shoot blasting techniques, were utilized. These
techniques were used where dense, non-rippable rock occurred within a minimum
' ' of 3 feet of finish pad grade, and above local Street elevations equivalent to
approximately 1 foot below the lowest utility invert elevation. Blasting operations
occurred within the ,street area in the general vicinity of Lots 1 through 9.
6.. Subsequent to completing removals, areas to receive compacted fill were scarified
to a minimum depth of 12 inches, moisture conditioned to at least optimum moisture
content, and then compacted to attain a minimum relative compaction of 90 percent.
,These areas were then' brought to grade with fill compacted to a minimum
90 percent relative compaction
6. ..'All processing of, original ground in areas to, receive fill, shown on Plates 1
through 4, was observed by a representative of GSI.
Fill Placement
Fill consisted of onsite and import materials which were placed in thin lifts, approximately
4 to .8 inches in thickness, brought to at least optimum moisture content, and compacted
to attain a minimum 90 percent relative compaction. Compaction test results on fills are
presented in the attached Table 1. Approximate as-built fill thicknesses are presented in
the attached Table 2. The preparation Iof some of these materials including processing of
shot rock and oversize rock through a rock crusher. .This process" generally produced
"6-inch minus" material, in accordance with guidelines presented in GSI (2002). Rock 'fills'
were not placed within this site.
Fill materials generated onsite, or within the larger Calavera Hills development, from either
raw excavation or produced at the crusher site, have been placed in general accordance
with recommendations presented in GSI (2002). An additional criteria, developed for this
project during grading, has included gradation testing (in general accordance with
ASTM D-422) of stockpiled materials produced from the rockcrusher. This testing has been
performed in order to determine the percentage of "fines" included in the stockpile material.
For this project, "fines" are considered to be earth materials that are 3/4 inch in diameter, or
finer. Suitable soil fills are considered 'to consist of earth materials with at least 40 percent
finer than 3/4 inch (GSI, 2003b). • ' ' ' ' ' ' '
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Slopes
Planned Slopes
In general, graded slopes constructed under the purview of this report should perform
satisfactorily with respect to gross and surficial stability, under normal conditions of
irrigation (discussed later), and rainfall, provided that these slopes are properly maintained.-
Fill slopes constructed under the purview of this report were provided with a keyway
excavated into suitable bedrock material in general accordance with recommendations
presented in Southern California Soils and Testing, Inc. (SCST, 1988) and as provided in
the field by this office. Cut slopes were constructed using cut and fill grading techniques
and/or blasting, and exposed dense igneous and/or metavolcanic rock. 'A detailed analysis
of slope stability has been completed under separate cover (GSl, 1998c).
Temporary Slopes
Temporary construction slopes may generally be constructed at a gradient of 1:1' (horizontal
to vertical) or flatter in compacted fill, and 1/2:1 (horizontal to vertical) in suitable bedrock
material (provided adverse geologiô structures are not present). Utility trenches may be
constructed in accordance with guidelines presented in Title 8 of the California Code of
Regulations for Excavation, Trenches and Earthwork with respect to Type B soil (compacted'
fill) and stable rock (bedrock). Construction materials and/or stockpiled soil should not be
stored within 5 feet from the top of any temporary slope. Temporary/permanent provisions
should be made to direct any potential runoff away from the top of temporary slopes.
Natural Slopes
Natural slopes should perform satisfactorily with respect to gross and surficial stability,
under normal conditions of irrigation and rainfall. ,
Field Testing
Field density tests were performed using the sand cone method (ASTM D-1 556) and
nuclear method (ASTM D-2922). Tests taken for the entire Calavera Hills project
were taken in consecutive numerical order. Only the test results for Village E-1 are
presented in Table 1 at the end of this report. The approximate locations of field
density tests are shown on the Compaction Test Location Map, Plates 1
through 4, which utilize the 40- scale grading plans (sheets 4 through 7), prepared
by Hunsaker & Associates, San Diego,, Inc., as a base map.
, Field density tests were taken at periodic intervals and random locations to check
the compactive effort provided by the contractor. Based on the operations observed,
test results presented herein are considered representative of the fills observed
under the purview of this report
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3. Visual classification of the soils in the field, as well as random laboratory testing,
was the basis for determining which maximum dry density value to use for a given
density test
4 Testing was performed on a full-time basis
LABORATORY TESTING
Moisture-Density Relations
The laboratory maximum dry density and optimum moisture content for each major soil
type was determined according to ASTM Test Method D-1557-91. The following table
presents the test results
Expansive Soils
Expansive soil conditions have been evaluated for the site. Representative samples of soil
near pad grade were recovered for classification and expansion testing. Expansion Index
(E.l.) testing was performed in general accordance with Standard 18-2 of the UBC.
Representative expansion indices indicate that site soils near pad grade, within the subject
lots, are very low to low expansive (E.l <50). A summary of soil expansion results are
presented in the attached Table.2.
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Soil Sulfate/Corrosion
Typical samples of the site materials were, analyzed for corrosion/soluble sulfate potential.
Soil sulfate testing indicates that the sulfate exposure to concrete is negligible, in
accordance with Table 19-A-4 of the UBC (1997). Corrosion testing indicates moderately
corrosive conditions for buried metal pipe in contact with soil for saturated conditions. Test
results are included in Appendix B. Alternative methods and additional comments may be
obtained from a qualified corrosion engineer.
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Sieve Analysis
Sample gradation for various representative samples was determined in general
accordance with ASTM Test Method D422. Test results are presented as Plates
B-i through B-5 in Appendix B
RECOMMENDATIONS - FOUNDATIONS
General
The foundation design and construction recommendations are based on laboratory testing
and engineering analysis of onsite earth materials by GSI. Recommendations for
conventional foundation systems are provided in the following sections. The foundation
systems may be used to support the proposed structures, provided they are founded in
competent bearing material. The proposed foundation systems should bedesigned and
constructed in accordance with the guidelines contained in the UBC., All footing designs
: should be reviewed by the project structural engineer. Based on the as-built fill thicknesses
(i.e., differential fill thickness exceeding 3:1, maximum to minirnuhi, across the lot) and soil
expansion potential, post-tension foundations are not required for the lots under the purview
of this report. Post-tension (PT) or conventional foundations may be used.
Recommendations for each type 'of foundation system are presented in the following
sections.
Conventional Foundation Design
Conventional spread and continuous footings maybe used to support the proposed
residential structures provided they are founded entirely in properly compacted fill
Or other competent bearing material (i.e., bedrock). ,Footings should not
simultaneously bear directly on bedrock and fill soils.
, Analyses indicate that an allowable bearing value of 2,000 pounds per square foot'
(psf) may be used for design of continuous footings per the attached Table 3, and for
design of isolated pad footings 24 inches square and 18 inches deep, into properly
'compacted fill or bedrock. The bearing value may be increased by ½ for seismic or
'other temporary loads. This value may be increased by 20 percent for each
additional 12 inches in depth, to a maximum of 2,500 psf. No increase, in bearing,
for footing width is recommended. • ' ' ' '
For lateral sliding resistance, a 0.4 coefficient of friction may be utilized for a
concrete to soil contact when multiplied by the dead load
A.... Passive earth pressure may be computed as an equivalent fluid having a density of
300 pounds per'cubic foot (pci) with ,a maximum earth pressure of 2,500 psf. '
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When combining passivpressureand frictional resistance; the passive pressure
component should be reduced by one-third.
Footings should maintain a horizontal distance or setback between any adjacent
slope face and the bottom outer edge of the footing. The horizontal distance may be
calculated by using h/3, where (h) is the height of the slope. The horizontal setback
should not be less than 7 feet; nor need not be greater than 40 feet (per code). The
setback may be maintained by simply deepening the footings. Flatwork, utilities or
. other improvements within a zone of h/3 from the top of slope may be subject to
lateral distortion. Footings; flatwork, and utilities setbacks should be constructed in
accordance with distances indicated in this section, and/orthe approved plans.
7. Provided that the recommendations contained in this report are incorporated into
final design and construction phase of development, a majority (>50 percent) of the
anticipated foundation settlement is expected to. Occur during construction.
Maximum settlement is not expected to exceed approximately ½-inch and should
occur below the heaviest loaded columns. Differential settlement is not anticipated
to exceed 1/4-inch between similar elements, in a 20 foot span.
Conventional Foundation/Concrete Slab Construction . . .
The following construction recommendations are based on generally very low to low
expansive bearing soils and maximum fill thicknesses of less than approximately 30 feet.
Conventional continuous footings should be constructed in accordance with
recommendations presented in Table 3, and in accordance with UBC (1997). All
footings should be reinforced per Table 3. . . .
. Detached isolated interior or exterior piers and columns should be founded at a
•• minimum depth of 18 inches below the lowest adjacent ground surface and tied to
the main foundation in at least one direction with a grade beam. Reinforcement
should be properly designed by the project structural engineer.
A grade beam reinforced as above, and at least 12 inches square, should be
provided across the garage entrances. The base.of the reinforced grade beam
should be at the same elevation as base of the adjoining footings.
The residential floor, and garage slabs should have a minimum thickness of
4 inches, in accordance with Table 3. Concrete used in floor slab construction
should have a minimum compressive strength of 2,500 psi.. • • • •
5 • Concrete slabs should be underlain with a minimum of 4 inches of sand. In addition,
a vapor barrier consisting of a minimum of 10-mil, polyvinyl-chloride membrane,
• with all laps sealed, should be provided at the mid-point of the sand layer. The slab
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subgrade should be free of loose and uncompacted material prior to placing
concrete.
6. Concrete floor slabs (residence and garage) should be reinforced' per Table 3. All
slab reinforcement should be supported to ensure proper mid-slab height
positioning during placement of the concrete. "Hooking" of reinforcement is not an
acceptable method of positioning. •:
7. Presaturation is not considered necessary for these soil conditions; however, the
moisture content of the subgrade soils should be equal to or greater than optimum
moisture to a depth of 12 inches below the adjacent ground grade in the slab areas,
and verified by this office within 72 hours of the vapor barrier placement.
B. Soils generated from footing excavations to be used onsite should be compacted to
a minimum relative compaction 90 percent of the laboratory standard, whether it is
to be placed inside the foundation perimeter or in the yard/right-of-way areas; This
- material must not alter positive drainage patterns that direct drainage away from the
structural areas and toward the street.
9. Proposed pools and other appurtenant structures should consider that excavation,
difficulties will likely be encountered in some lots at depths greater than
approximately 3 feet below existing building pad grades due to the presence of
dense granitic rock. Please refer to Table 2 for a listing of lots withrelatively shallow
(i.e., <lOfeet) fills. S
10. As an alternative, an engineered PT foundation system' may be used.
Recommendations for PT slab design are presented in the following Section.
PT Slab Foundation Systems
• PT slabs may be utilized for construction of typical one-'and two -story residential
structures onsite. The information and recommendations presented in this section
are not meant to supercede design by a registered structural engineer or civil
engineer familiar with PT slab design br.corrosion engineering consultant.
From a soil expansion/shrinkage standpoint, a fairly common contributing factor to
distress of structures using PT slabs is a significant fluctuation in the moisture
content of soils underlying the perimeter of the slab, compared to the center, causing
a "dishing" or "arching" of the slabs. To mitigate this possible phenomenon, a
combination of soil presaturation (if necessary, oràfterthe project has been dormant
for a period of time) and construction of a perimeter "cut off' wall grade beam may
be employed.
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3. For very low to low (E.l.= 0 through 50) expansive soils, perimeter and mid span
r beams should be a minimum 12 inches deep below lowest adjacent pad grade.
The perimeter foundations maybe integrated into the slab design or independent
of the slab The perimeter beams should be a minimum of 12 inches in width
A. vapor barrier should be utilized and be of sufficient thickness to provide an
adequate separation of foundation from soils (10 mil thick). The vapor barrier should.
be lapped and adequately sealed to provide a continuous water-resistant barrier
under the entire slab. The vapor barrier should be sandwiched between two 2-inch
thick layers of sand (SE > 30) for a total of 4 inches of sand
4 Isolated piers should be incorporated into the PT slab system
5. ., Specific soil presaturation for slabs is not required for very low expansive soils;
•however, the moisture content of the subgrade soils should be at or above the soils'
optimum moisture content to a minimum depth of 18 inches below grade,
depending on the, footing embedment. .
6 PT slabs should be designed using sound engineering practice and be in
accordance with the Post-Tension Institute (P11), local and/or national code criteria
and the recommendations of a structural or civil engineer qualified in PT slab
design. Alternatives to P11 methodology may be used if equivalent systems can be
proposed which accommodate the angular distortions, expansion parameters, and
settlements noted.-for this project. If alternatives to PTl are suggested by the
structural consultant, consideration should be given for additional review by a
qualified structural PT designer. Soil related parameters for PT slab design, are
presented on the following
Perimeter Footing Embedment*' 12"
Allowable bearing value . . 1000psf**
Modules of subgrade reaction 125 psi/inch
Coefficient of friction . .. . 0.35
Passive pressure . .' . . 275 pcf
Soil Suction (P1) : , 3.6
Depth to Constant Soil Suction . . , 5 feet '
Thornthwaite moisture ' -20.0
em edge . ' 2.5
em center . • . . 5.0
my edge . 0.25
m center
'I •
' 1.00.
1inimum Slab Thickness . 5 inches
* Lab data indicates E.I. 0-50 for this site. • ..
**Bearing for slab on grade only, bearing value for interior or perimeter beams
should be in accordance with parameters provided for conventional continuous
and isolated spread footings.
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7. Provided that the recommendations contained in this report are incorporated into
final design and construction phase of development, a majority (>50 percent) of the
•• anticipated foundation settlement is expected to occur during construction.
Maximum settlement is not expected to exceed approximately ½-inch, and should
occur below the heaviest loaded columns. Differential settlement is not anticipated
to exceed ¼-inch between similar elements, in a20 foot span
Designers of PT slabs should review the parameters provided for PT slabs, and
compare using a span distance of 5 feet, using a module of subgrade reaction of
125 psi in their evaluation
8. In accordance with guidelines presented in the UBC, improvements and/or footings.
should maintain a horizontal distance, X, between any adjacent descending slope
face and the bottom outer edge of'the improvement and/or footing. The horizontal
distance, X, may be calculated by using X = h/3, where h is the height of the slope.
X should not be less than 7 feet, nor need not be greater than 40 feet. X may be
maintained by deepening the footings. Improvements constructed within a distance
of h/3 from the top of slope may be subject to lateral distortion.
Foundations for any adjacent structures, including retaining walls, should be
. deepened (as necessary) to below a 1:1 projection upward and away from any
Proposed lower foundation system. This recommendation may not be considered
valid, if the additional surcharge imparted by the upper foundation on the lower
foundation has been incorporated into the design of the lower foundation.
Additional setbacks, not discussed orsuperceded herein, and presented in the UBC
are considered valid. .
EXTERIOR FLATWORK
Exterior driveways, walkways, sidewalks, or patios, using concrete. slab on grade
construction should be designed and constructed in accordance with the following criteria:
Driveway slabs should be a minimum 4 inches in thickness; all other exterior slabs •
may be a nominal 4 inches in.thickness. A thickened edge should be considered
for all flatwork adjacent.to landscape areas. • . • •
. Slab subgrade should be compacted to a minimum 90 percent relative compaction
and moisture conditioned to at or above the soils optimum moisture content
.3. The use of transverse and longitudinal control joints should be considered to help
• • control slab cracking due to concrete shrinkage or. expansion. Two of the best ways
to control this movement are: 1) add a sufficient amount of reinforcing steel,
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increasing tensile strength of the slab; and/or 2) provide an adequate amount of
control and/or expansion joints to accommodate anticipated concrete shrinkage and
expansion. We would suggestthatthe maximum control joint spacing be placed on
5 to 8 foot centers or the smallest dimension of the slab, whichever is least
No traffic should be allowed upon the newly poured concrete slabs until they have
been properly cured to within 75 percent of design strength
Positive site drainage should be maintained at all times. Adjacent landscaping
should be graded to drain into the street, parking area, or other approved area. All
surface water should be appropriately directed to areas designed for site drainage
6 Concrete compression strength should be a minimum of 2,500 psi
CONVENTIONAL RETAINING WALLS/WALLS
General
i Foundations may be designed using parameters provided in the Design Section of the
Foundation Recommendations presented herein. Wall sections should adhere to the
County of San Diego and/or City of Carlsbad guidelines. All wall designs should be
reviewed by qualified structural engineer for structural capacity, overturning, and seismic
resistance stability per the UBC.
The design parameters provided assume that select onsite or equivalent very low
expansive soils are used to backfill retaining walls, from a 1:1 (horizontal to vertical)
projection upward and away from the heel fo the footing. If expansive soils are used to
backfill the proposed walls within this wedge, increased active and at-rest earth pressures
will need to be utilized for retaining wall design. Heavy compaction equipment should not
be used above a 1:1 projection up and away from the bottom of any wall.
The following recommendations are not meant to apply to specialty walls (cribwalls, loffel,
earthstone, etc.). Recommendations for specialty wallswill be greater than those provided
herein, and can be provided upon request. Some movement of the walls constructed
should be anticipated as soil strength parameters are mobilized. This movement could
cause some cracking dependent upon the materials used to construct the wall. To reduce.
wall cracking due to settlement, walls should be internally grouted and/or reinforced with
steel.
Restrained Walls
Any retaining walls that will be restrained prior to placing and compacting backfill material
or that have re-entrant or male corners, should be designed for an at-rest equivalent fluid
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pressures of 60 pcf, plus any applicable surcharge loading. For areas of male or re-entrant
corners, the restrained wall design should extend a minimum distance of twice the height
of the wall (2H) laterally from the corner. Building walls below grade, should be
water-proofed or damp-proofed, depending on the degree of moisture protection desired.
Refer to the following section for preliminary recommendations from surcharge loads.
Cantilevered Walls
These recommendations are for cantilevered retaining walls up to 15 feet high. Active earth
pressure may be used for retaining wall design, provided the top of the wall is not restrained
from minor deflections. An empirical equivalent fluid pressure (EFP) approach may be
used to compute the horizontal pressure against the wall. Appropriate fluid unit weights are
provided for specific slope gradients of the retained material. These do not include other
superimposed loading conditions such as traffic, structures, seismic events or adverse
geologic conditions. V V
The equivalent fluid density should be increased to 60 pcf for level backfill at the angle point
of the wall (corner or male re-entrant) and extended a minimum lateral distance of 2H (two
times the wall height) on either side of the corner. Traffic loads within a 1:1 projection up
from the wall heel, due to light trucks and cars should be considered as a load of 100 psf
per foot in the upper 5 feet of wall in uniform pressure. For preliminary design purposes,
footing loads within a 1:1 backfill zone behind the wall will be added to the walls as 1/3 of
the bearing pressure for one footing width, along the wall alignment.
Sound Walls
Foundations for top of slope sound walls, using concrete block construction, may be
constructed in accordance with conventional foundation recommendations presented in
this report. Foundations should maintain a minimum lateral distance of 7 feet from the
outside bottom edge of the wall footing to the face of any adjacent slope.
Wall Backfill and Drainage
V
All retaining walls should be provided with an adequate gravel and pipe back drain and
outlet system to prevent buildup of hydrostatic pressures, and be designed in accordance
with minimum standards presented herein. Retaining wall drainage and outlet systems
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should be reviewed by the project design civil engineer and incorporated into project plans.
Pipe should consist of schedule 40 perforated PVC pipe. Gravel used in the back drain
systems should be a minimum of 3 cubic feet per lineal foot of 3/ to 11/2-iflCh clean crushed
rock encapsulated infilterfabric (Mirafi 140orequivalent). Perforations in pipe should face
down. The surface of the backfill should be sealed by pavement or the top 18 inches
compacted to 90 percent relative compaction with native soil Proper surface drainage
should also be provided
As an alternative togravel back drains, panel drains (Miradrain 6000, Tensar, etc.) may be
used. Panel drains should be installed per manufacturers guidelines. Regardless of the
back drain used, walls should be water proofed where they would impact living areas or r where staining would be objectionable
Wall Footing Transitions
Site walls are anticipated to* be supported on footings designed in accordance with the
recommendations in this report. Wall footings may transition from bedrock to fill. If this
condition is present the civil designer may specify either
a) A minimum of a 2-foot, 'overexcavation and recompaction of bedrock
materials, as measured for a distance of 2H from the transition in the direction
of the wall. Overexcavations should be completed for a minimum lateral'
distance of 2 feet beyond the footing, measured perpendicular to the wall.
b) Increase the amount of reinforcing steel.and wall detailing (i.e., expansion
joints or crack control joints) such that a angular distortion of 1/360 for a
distance of 2H on either side of the transition may be accommodated.
Expansion joints should be sealed with a flexible grout.
Embed the-footings entirely into native formational material. If transitions
from cut to fill transect the wall footing alignment at an angle of less than
45 degrees (plan view), then the designer should follow recommendation "a".
(above) and until such transition is between 45 and 90 degrees to the wall
alignment. :
PAVEMENTS
Pavement design for streets has not been performed to date. Concrete driveway
pavements outside the public right of way maybe constructed per the exterior concrete slab
recommendations presented in this report. Based on the type of earth materials
encountered, minimum pavement sections (per City standards) may be anticipated. Final
pavement design will be provided upon completion of underground improvements and
"R"-value testing. •• ••. • •••
Calavera Hills II, LLC; • • W.O 3495-B-Sc
Calavera Hills, Village E-1 •
• •. • June 9, 2003
File e \wp9\3400\3459b rrg Page 13
GeoSoils, Inc.
DEVELOPMENT CRITERIA
Graded Slooe Maintenance and Plantinci
Water has been shown to weaken the inherent strength of all earth materials. Slope
stability is significantly reduced by overly wet conditions. Positive surface drainage away
from graded slopes should be maintained and only the amount of irrigation necessary to
sustain plant life should be provided for planted slopes. Over-watering should be avoided
as it can adversely affect site improvements. Graded slopes constructed within and
utilizing onsite materials would be erosive. Eroded debris maybe minimized and surlicial
slope stability enhanced by establishing and maintaining a suitable vegetationcover soon
after construction. Compaction to the face of fill slopes would tend to minimize short-term
erosion until vegetation is established. Plants selected for landscaping should be light
weight, deep rooted types that require little water and are capable of surviving the prevailing
climate If plants are selected other than those recommended above, the potential for
perched water conditions to develop will increase. Recommended, plant selection and
irrigation practices should be provided to each individual homeowner, as described above
and below. '
'. . . . . . .
Landscape Maintenance .
Only the amount of irrigation necessary to sustain plant life should be provided. Over
watering the landscape areas could adversely affect proposed site improvements, and will
increase the potential for perched water to develop. The slope areas should be planted
with drought resistant vegetation. Consideration should be given to the type of vegetation
chosen and their potential effect upon surface improvements (i.e., some trees will have an
effect on concrete flatwork with their extensive root systems).
From a 'geotechnical standpoint, leaching is not recommended for establishing
landscaping. If the surface soils are processed for the purpose of adding amendments,
they should be recompacted to 90 percent minimum relative compaction.
'Drainage
. .
Positive site drainage should be maintained at all times, and should be incorporated into
'homeowner improvements. Drainage should not flow uncontrolled down any descending
slope. Water should be directed away from foundations and not allowed to pond and/or
seep into the ground. Pad drainage should be directed toward the street or other approved
area. Roof gutters and down spouts should be considered to control roof drainage. Down
spouts should outlet a minimum 'of 3 feet from proposed structures and/or in accordance
with the recommendations of the design civil engineer. We would'recommend'that any
proposed open bottom planters adjacent to proposed structures be eliminated for a
minimum distance of 10 feet. As an alternative,, closed bottom type planters could be
utilized. An outlet placed in the bottom of the planter could be installed to direct drainage
Calavera Hills II, LLC . . . . ' . . , W.O. 3495-B-SC
Calavera Hills, Village E-1 ' ' , .. . ' ' June 9, 2003 'Fi1e:e:\wp9\3400\3459b.rrg
, ' ' S ' . ' Page 14
GeóSoils, Inc.'
away from structures or any exterior concrete flatwork. Owing to the' nature of site
materials, the potential for perched groundwater, as a result of contrasting permeabilities
of fill and/or bedrock, may not be precluded. Accordingly, perched water conditions should
be anticipated subsequent to grading. Should such conditions develop, this office should
be contacted to provide mitigative recommendations
Footinci Trench Excavation
All footing excavations should be observed by a representative of this firm subsequent to
trenching and prior to concrete form and reinforcement placement. The purpose of the
observations is to verify that the excavations are, made into the, recommended bearing
material and to the minimum widths and depths recommended for construction. If loose
or compressible materials are exposed within the footing excavation, a deeper footing or
removal and recompaction of the subgrade materials would be recommended at that time.
All excavations should minimally conform to CAL-OSHA and local safety codes.
Footing trench spoil and any excess soils generated from utility trench excavations should
be compacted to a minimum relative compaction of 90 percent if not removed from the site.
Additional Site lmDrovements
If, in the future, any 'additional improvements are planned for the site, recommendations
concerning the geological or geotechnical aspects of design and construction of said
improvements could be provided upon request. Proposed pools or other appurtenant
structures should consider that excavation difficulties will likely be encountered in some lots
(see Table 2) at depths greater than 3 feet ,below existing building pad grade. Subdrainage '
should be provided for spa and pool homeowner improvements S
Additional Grading
This office should be notified in advance of any additional fill placement, regrading of the
site, or trench backfilling after rough grading has been completed. This includes any
grading, utility trench, and retaining wall backfills. All excavations should be observed by
one of,our representatives and conform to CAL-OSHA and local safety codes.
Utility Trench Backfill
1. All interior utility trench backfill should be brought to at least 2 percent above
optimum moisture content and then compacted to, obtain a minimum relative
compaction of 90 percent of the laboratory standard'. As an alternative for shallow
(12 inch to 18 inch) under-slab trenches, sand having a sand equivalent value of 30
or greater may be utilized and jetted orflooded into place. Observation, probing and
'testing should be provided to verify the desired results.
Caiavera Hills II, LLC ' ' ' ,' ' , W.O. 3495-B-SC
Calaverá Hills, Village E-1 ' , S , June 9, 2003
Fi1e:e:\wp9\3400\3459b.rrg S , , Page 15
GeoSoils, Inc. ,
.2. "Exterior trenches adjacent to, and within areas extending below a 1:1 plane
Projected from the outside bottom edge of the footing, and all trenches beneath
hardscape features and in slopes, should be compacted to at least 90 percent of the
laboratory standard. Sand backfill, unless excavated from the trench, should not be
used in these backfill areas. Compaction testing and observations, along with
probing, should be accomplished to verify the desired results.
3. All trench excavations should conform to CAL-OSHA and local safety codes.
PLAN REVIEW
Final foundation and improvement plans, including homeowner improvement plans (as
described below), should be submitted to this office for review and comment, as they
become available,, to minimize any misunderstandings between the plans •and
recommendations presented herein. In addition, foundation excavations and earthwork
construction performed, on the site should be observed and tested by this office. If
conditions are found to differ substantially from those stated, appropriate recommendations
would be offered at that time....
. .. . . . •.. . . .. ..
SUMMARY OF RECOMMENDATIONS REGARDING
GEOTECHNICAL OBSERVATION AND TESTING. .
We recommend that observation and/or testing be 'performed by the geotechnical.
consultant at each of the following construction stages:
During grading/recertification
After excavation of building footings, retaining wall footings, and free standing walls
footings, prior to the placement of reinforcing steel or concrete. -
' During retaining wall subdrain installation, prior'to backfill placement. '
' During placement of backfill for area drain, interior plumbing, utility line trenches,
and retaining wall backfill. ... .. ' '
After presoaki n g/presatu ration of building pads and other flatwork subgrade; prior.
to the placement of reinforcing steel or concrete. . . .
• . During slope construction/repair. , . . . . ' . . '• . . , .
When any unusual soil or groundwater conditions are encountered during any
construction operations, subsequent to.the issuance of this report.
Caiavera Hills II, LLC • • '
. • ; W.O. 3495-B-SC
Calavera Hills, village E-1 ., • . • • •.
.
. • June 9, 2003. • File:e:\wp9\3400\3459b.rrg 0
• • : .
• '0 ' 0'
Page 16
GeoSoils, Inc. . • . . . . . •.
When homeowner improvements, including flatwork, spas, pools, walls, etc, are
constructed.
REGULATORY COMPLIANCE
Removals, processing 'of original ground cuts; and fills have been observed and
compaction testing performed under the purview of this report have been completed using
the selective testing and observations services of GSI. Earthwork was found to be in
compliance with the Grading Code of the City of Carlsbad, California. Our, findings were
'made and recommendations prepared in conformance with generally accepted
professional engineering practices and no further warranty is implied nor made. This report
is subject to review by the controlling authorities for this project. GeoSoils, Inc. should not'
be held responsible nor liable for work, testing, or recommendations performed or provided
by others. ' •• ' ' ' ' , , :
The opportunity to be of service is sincerely appreciated. If you should have any questions,
please do not hesitate to call our office. ' ' ' '• ••; "
Or F
Respectfully submitted
G.
GeoSoils, Inc / ff \( Reviewed by i RC 4787 2
, Ji)j
Robert G. Crisman , David W. Skelly
Project Geologist, CEG 1 934'—_- , Civil Engineer, RCE 47857
RGC/DWS/JPF/Jk
Attachments: Table 1 - Field Density Test Results
Table 2 - Lot Characteristics' '
Table 3 - Foundation' Construction Recommendations
Appendix A - References
Appendix B - Laboratory Test Results
Plates 1 through 4 - Field Density Test Location Maps,
Distribution: (4) Addressee • •
Calavera Hills lI,LLC • • • • •• • • • ' ' W.O. 3495-B-SC
Calavera Hills Village E 1 June 9 2003
Fi1e:e:\wp9\3400\3459b.rrg ' • • • • • Page 17
GeoSoils, Inc.
.
d) clvll~
* I)
TEST
NO.
DATE. TEST LOCATION TRACT
NO.
ELEV
OR
DEPTH (It)
MOISTURE
CONTENT
(%)
DRY
DENSITY
(pcf)
REL
COMP
(%)
TEST
METHOD
SOIL
TYPE
514 2/19/03 Lot 23 Village E-1 367.0 104 120.0 91.6 ND G
515 2/19/03 Lot 23 Village E-1 365.0 . 10.9 121.2 925 ND G
516 2/19/03 Lot 23 Village E-1 368.0 10.2 119.3 91.1 ND G
517' 2/19/03 Lot 28 Village El 362.0 9.9 120.3 91.8 ND G
518 2/19/03 . Lot 16 Village E-1 362.0 10.2 118.4 90.4 ND G
668 3/10/03 Bldg 21 Village E-1 374.0 10.3 126.8 91.2 ND LI
-. -
670 3/10/03 Bldg 21 Village E-1 376.0 9.9 126.5 91.0 ND H -
672 3/10/03 . Bldg 11 Village E-1 373.0 10.1 126.4 90.9 ND - -
674 3/10/03 Bldg 12 Village E-1 372.0 10.5 126.9 91.2 ND H - -
676 3/11/03 Bldg 10 Village E-1 374.0 10.2 126.4 90.9 ND H -
677 3/11/03 Bldg 11 Village E-1 374.0 10.3 126.1 .90.7 ND H
678 3/11/03 Bldg 11 Village E-1 - 375.0 10.5 126.9 91.2 ND H
695 3/17/03 Lot 10 Village E-u 375.0 10.6 120.1 91.7 ND H
-
696 3/17/03 .Lot 10 Village E-1 374.0 11.2 120.9 923 ND H:
697 3/17/03 Lot 10 Village E-1 376.0 9.9 121.6 92.8 ND H
698 3/17/03 Lot 10 Village E-1 376.0 10.5' 119.5 .91.2 ND H
699 3/17/03 Lot 24 Village E-1 367.0 10.1 118.9 90.8 ND H
706 3/18/03 Rec Lot Village E-1 368.5 9.4 120.3 91.8 ND H
707 3/18/03 Rec Lot . ' Village E-1 370.5 9.1 120.8 92.2 ND H.'
750 3/18/03 Lot 22 ' Village E-1 369.0 9.5 118.2 90.2 ND H
751 3/18/03 Lot 24 Village E-1 371.0 10.1 ' 120.9 92.3 ND H
752 3/18/03 . Lot 22 . Village E-1 370.0 9.6 122.5 935 ND H
767 3/24/03 Lot8 Village E-1 375.0 ' 10.2 119.6 91.3 ND . H
.768 3/24/03 Lot 9 Village E-1 - 376.0 11.1 _118.8 90.7 ND H - -
769 3/24/03 . Lot 24 Village E-1
-
371.0 .9.2 121.2 92.5 ND H
770 3/24/03 Lot 22 Village E-1 - 373.0 9.9 119.3 91.1 ND H - -
771 3/24/03 Lot 26 Village E-1
- 370.0 10.4 _119.7 91.4 ND H -
772 3/24/03 Lot 27 Village E-1 367.0 9.6 121.7 92.9 SC H - -
773 3/25/03 Lot 23 Village E-1 364.0 10.2 118.9 90.8 ND - H
-
774 3/25/03 Lot 24 Village E-1 369.0 11.8 119.5 91.2 ND -
775 3/25/03 Lot 27 Village E-1 366.0 11.1 119.2 91.0 ND H -
.776 3/25/03 Lot 27 . Village E-1 368.0 11.4 122.4 93.4 ND . - -
777 3/26/03 Lot 28 Village E-1 360.0 . 12.2 121.6 92.8 ND - -
778 3/26/03 Lot 28 Village E-1 355.0 11.9 120.0 91.6 ND - -
779 3/26/03 Lot 28 Village E1 361.0 11.2 119.3 91.1 ND - -
780 3/26/03 .Lot 27 Village E-1 368.0 10.4 121.2 92.5 ND - H
781 3/26/03 Lot 25-26 Village E-1 372.0 11.1 119:6 91.3 ND - H
782 3/26/03 Lot 15 Village E-1 359.0 12.0 118.7 90.6 ND H -
789 4/1/03 Private Drive Lot Village E-1 355.0 10.2 121.7 92.5 ND _H -
790 4/1/03 Lot 14 Village E-1 - 356.0 11.9 124.8 95.3 ND H
791* 4/1/03 . Lot 14 . Village E-1360.0 4.8 112.1 .85.6 ND H
791A 4/1/03 . Lot 14 ' Village E-1 360.0 9.2 112.7 90.6 ND H
792 .4/1/03 Lot 14 Village E-1 363.0 11.0 118.9 90.8 ND H
793 4/1/03 Lot 14 ' . Village E-1 361.0 10.9 .. 123.3 94.1 ND H
794 4/1/03 Lot 1 . . Village E-1 362.0 11.6 120.1 91.7 ND H
795 4/1/03 Lot Village E-1 362.0 10.3 120.8 . 92.2 ND H
796 4/1/03 Lot . Village E-1 363.0 9.1 118.9 . 90.8
797 4/1/03 Lot Village E-1 364.0 9.4 120.0 91.6 - -
I
. Calavera Hills II, LLC .'. . . . . . . - . . - . W.O. 3459-B-SC
Calavera Hills, Village E-1 '. . - . . . . . . - June 2003
File: C:\excel\tables\3400\3459b.E1
.
GeoSoits, Inc. .- .
.
' Page 1
ND ) fl _
ND H.
Table 1
FIELD DENSITY TEST RESULTS
TEST
NO.
DATE TEST LOCATION TRACT
NO:
ELEV
OR
DEPTH (It)
MOISTURE
CONTENT
(%)
DRY
DENSITY
(pci)
COMP
REL.':TEST:',..*SOIL
METHOD TYPE
798 4/1/03 Front Lot 15 Village E-1 363.0 10.1 118.3 90.3 NO Li
824 3/31/03 Lot 18 Village E-1 369.0 10.2 119.8 91.5 NO H -
825 3/31/03 Lot 19 Village E-1 371.0 1 9.8 121.3 92.6 ND H -
826 3/31/03 Private Drive Lot Village E-1 350.0 9.3 122.3 93.4 ND - -
827 4/4/03 Lot 14 Village E-1 355.0 9.9 120.3 91.8 NO - -
828 4/4/03 Lot 20 Village E-1 375.0 10.3 121.3 92.6 ND -
829 4/4/03 Lot Village E-1 372.0 10.4 123.7 944 NO - -
830 4/4/03 Lot 19 Village E-1 373.0 9.6 121.7 92.9 ND - -
838 4/8/03 Lot 17 Village E-1 368.0 10.8 121.4 92.7 NO - -
839 4/8/03 Lot 17 Village E-1 370.0 11.2 123.4 942 NO - -
840 4/8/03 Lot 25 Village E-1 370.0 11.1 123.8 945 NO - -
841 4/8/03 Lot 25 Village E-1 372.0 10.5 123.1 940 NO - H -
867 4/11/03 Private Or B Village E-1 363.0 9.1 122.1 91.1 NO -
868 4/11/03 Private Or Village E-1 367.0 8.9 122.6 91.5 NO - -
869 4/11/03 Lot Village E-1 351.0 9.6 123.4 92.1 NO
870 4/11/03 Lot Village E-1 356.0 9.3 123.9 92.5 NO -
884 4/16/03 Lot Slope Face Village E-1 362.0 14.2 109.6 90.9 NO A
885 4/16/03 Lot Slope Face Village E-1 360.0 14.5 109.2 90.6 NO A
886 4/16/03 Lot Slope Face Village E-1 363.0 14.4 109.4 90.7 NO A
895 4/17/03 Lots 3-4 (Sewer Easm) Village E-1 362.0 9.6 124.5 92.9 ND -
896 4/17/03 Drive B 27+50 Village E-1 354.0 9.1 125.7 93.8 NO -
897 4/18/03 12+50 Private Drive B Village E-1 354.0 9.8 121.9 90.9 NO - -
898 4/18/03 11+40 Village E-1 356.0 9.5 122.2 91.1 NO - -
899 4/18/03 10+20 Village E-1 356.0 9.3 121.7 90.8 ND - -
900 4/18/03 Lot Village E-1 366.0 9.1 121.8 90.8 NO
922 4/23/03 Lot 5 Village E-1 369.0 9.3 126.9 94.7 SC
923 4/23/03 Lot 4 Village E-1 368.0 8.6 127.6 95.2 NO - -
924 4/23/03 Lot 3 Village E-1 366.0 8.2 124.9 93.2 NO - -
933 4/24/03 Private Or B 14+00 Village E-1 370.0 9.3 127.2 94.9 SC -
934 4/24/03 Private Or B 12+50 Village E-1 363.0 10.1 125.4 93.6 ND - -
935 4/24/03 Private Or B 11+30 Village E-1 360.0 9.6 127.8 95.4 ND -
936 4/24/03 Private Or B 13+50 Village E-1 369.0 8.4 124.4 92.8 NO -
937 4/24/03 Private Or B 11+90 Village E-1 364.0 9.8 123.0 91.8 NO - -
943 4/25/03 Private Or B 14+90 Village E-1 370.0 9.7 127.0 94.8 ND - -
944 4/25/03 Private Or B 19+50 Village E-1 360.0 10.5 122.9 91.7 NO - - 945* 4/25/03 Private DrB21 +00 Village El 359.0 12.9 116.4 869 NO -
945A 4/25/03 Private Or B 21+00 Village E-1
- 359.0 10.8 125.6 93.7 ND - -
946 4/25/03 Private Or B 22+50 Village E-1 - 358.0 9.9 123.5 92.2 SC - -
947 4/25/03 Private Or B 20+00 Village E-1 364.0 11.5 128.4 95.8 ND .1 -
948 4/25/03 Private Or B 21 +00 Village E-1 361.0 10.9 124.9 932 NO - -
955 4/29/03 Private Or B 17+30 Village E-1 365.0 9.3 122.3 91.3 NO - -
956* 4/29/03 Front Lot 23 Village E-1 366.0 10.2 119.5 88.4 NO -
956A 4/29/03 Front Lot 22 Village E-1 366.0 9.7 125.4 93.6 NO -
957 4/29/03 Front Lot 23 Village E-1 367.0 10.0 121.8 90.9 NO = = 958 4/29/03 Front Lot 23 Village E-1 369.0 9.1 126.1 94.1 ND
959 4/29/03 End Lot 14 Village E-1 360.0 8.6 126.1 94.1 NO I -
960 4/29/03 End Lot 14 Village E-1 LEN
961
363.0 8.8 127.3 95.0
4/29/03 Private Dr B 23+50 Village E-1 357.0 9.1 124.2 92.7 =
W.O. 3459-B-SC
June 2003 ,Soils, Inc. Page 2
Table 1
FIELD DENSITY TEST RESULTS
TEST
NO.
DATE TEST LOCATION TRACT
NO.
ELEV
OR
DEPTH (It)
MOISTURE
CONTENT
(%)
DRY
DENSITY
(pci)
REL
COMP
TEST
METHOD
SOIL
TYPE
962 4/29/03 Private Dr B 25+50 Village E-1 355.0 9.0 123.1 91.9 ND - - FG-965 5/1/03 Bldg 27 Village El FG 9.6 129.2 96.4 ND - - FG-966 5/1/03 Bldg 26 Village E-1 FG 8.7 127.7 95.3 ND - - FG-967 5/1/03 Bldg 24 Village El FG 8.6 127.6 95.2 ND
- - FG-968 5/1/03 Bldg 8 Village E-1 FG 9.0 126.8 946 ND - - FG-970 5/1/03 Bldg 7 Village E-1 FG 8.2 125.8 93.9 ND
- - FG-971 5/1/03 Bldg 6 Village E-1 FG 8.9 126.9 94.7 ND - - FG-1007 5/9/03 Lot Village E-1 FG 10.3 128.4 95.8 ND I - FG-1008 5/9/03 Lot Village E-1 FG 10.1 128.9 96.2 ND
FG-1009 5/9/03 Lot Village E-1 FG 9.6 126.1 94.1 ND
FG-1010 5/9/03 Lot 18 Village E-1 FG 9.9 125.3 93.5 ND I - FG-1011 5/9/03 Lot 19 Village E-1 FG 10.5 121.7 90.8 ND I
FG-1012 5/9/03 Lot 20 Village E-1 FG 11.0 126.0 940 ND
FG-1013 5/9/03 Lot Village E-1 FG 10.1 129.3 96.5 ND
- - FG-1014 5/9/03 Lot 10 Village El FG 9.0 124.8 93.1 ND - FG-1015 5/12/03 Lot 28 Village E-1 FG 9.1 126.4 943 ND - - FG-1016 5/12/03 Lot 15 Village E-1 FG 8.6 122.7 91.6 ND - - FG-1017 5/12/03 Lot 16 Village E-1 FG 8.5 124.9 93.2 ND - - FG-1018 5/12/03 Lot 17 Village E-1 FG 8.9 124.6 93.0 1 ND - - FG-1019 5/12/03 Lot 25 Village E-1 FG 9.6 124.2 92.7 ND - - 1027 5/13/03 Private DrC10+80 Village E-1 362.0 10.0 121.9 91.0 ND - - .1028 5/13/03 Private Dr C 11+80 Village E-1 364.0 10.2 121.8 90.9 ND - FG-1033 5/14/03 Bldg 11 Village E-1 FG 8.6 124.4 92.8 ND
- FG-1034 5/14/03 Bldg 12 Village E-1 FG 9.2 125.8 93.9 ND - - FG-1035 5/14/03 Bldg 21 Village E-1 FG 8.5 128.1 95.6 ND - - FG-1036 5/14/03 Bldg 23 Village E-1 FG 8.4 123.8 92.4 ND - - FG-1037 5/14/03 Bldg 14 Village E-1 FG 9.2 127.0 94.8 ND - - FG-1038 5/14/03 Bldg 1 Village E-1 FG 91.1 126.1 94.1 ND - - FG-1039 5/14/03 Bldg 2 Village E-1 FG 9.3 124.9 93.2 ND
- 1063 5/20/03 . Lot 13 Village E-1 370.0 9.8 124.9 93.2 ND - I
1064 5/20/03 Lot 13 Village E-1 371.0 8.8 126.1 94.1 NO _l - 1065 - 5/20/03 Private DrB23+00 Village E-1 361.0 9.1 121.4 90.6 ND - - 1066 5/20/03 Private Dr B 21+20 Village E-1 364.0 10.3 123.3 92.0 ND
- 1067 5/20/03 Private Dr B 19+80 Village E-1 366.0 10.1 122.1 91.1 ND - - 1097 5/27/03 Pvt Dr B 16+50 Village E-1 367.0 9.8 121.9 91.0 ND - - 1098 5/27/03 Pvt Dr B 16+75 Village E-1 370.0 8.7 125.4 93.6 ND I - 1099 5/27/03 Pvt Dr B 16+25 Village E-1 370.0 9.3 123.4 92.1 ND I
1100 1 5/27/03 Bldg 21 Village E-1 374.0 9.9 122.5 91.4 ND I
FG-1101 5/27/03 Bldg 22 Village E-1 FG 8.6 127.2 949 ND I
FG-1102 5/27/03 Bldg 13 Village E-1 FG 8.5 127.6 95.2 ND I
Legend
* = Indicates Failed Test
A = Indicates Re-Test
ND = Nuclear Densometer
SC = Sand Cone
FG = Finish Grade
Calavera Hills II, LLC W.O. 3459-B-SC
Calavera Hills, Village E-1 June 2003
File: C:\excel\tables\3400\3459b.E1 GeoSoils, Inc. ' Page 3
LOT
E.
(per UBC
Standard 18-2)
-
EXPANSION
POTENTIAL'
SOLUBLE
SULFATE
(weight
percent)::
SULFATE
EXPOSURE 2
-:t-
DEPTH
(Range In Ft.)
OF FILL,:,-.:FOUNDATION
CATEGORY (3)
1 0 Very Low 0.0064 Negligible 2-4 I
2 0 Very Low 0.0064 Negligible 3-4 I
3 0 Very Low 0.0064 Negligible 3 I
4 0 Very Low 0.0064 Negligible 3-10
5 0 Very Low 0.0064 . Negligible 3-5 I
6 0 Very Low 0.0064 Negligible . 3-5 .
7 0 Very Low 0.0064 Negligible 3-4 I
8 0 Very Low 0.0064 Negligible 3 . I
9 0 Very Low 0.0064 Negligible 3-4 I
10 0 Very Low 0.0064 Negligible 3-6 I
11 0 Very Low 0.0088 Negligible 3-5. I
12 0 Very Low 0.0088 . Negligible 3-6 I
13 0 Very Low 0.0088 Negligible . 3-4 . I
14 0 Very Low 0.0088 Negligible 3-6 I
15 1 Very Low 0.0088 Negligible . . 3-4 I
16 1 Very Low 0.0088 Negligible 3-4 I
17 1 Very Low 0.0088 Negligible. . 3-4 I
18 : 1 Very Low 0.0088 Negligible 5 I
19 1 Very Low 0.0088 Negligible 3-5 . .1
20 1 Very Low 0.0088 Negligible 4-5
21 1 Very Low. 0.0088 Negligible 4-5 I
22 2 Very Low 0:0055 Negligible 3-8 . I
23 2 Very Low 0.0055 Negligible 4-6 . I
24 2 .. Very Low 0.0055 Negligible.
5
4-7 . S I
1-
E I SOLUBLE DEPTH
(per UBC . EXPANSION SULFATE SULFATE OF FILL FOUNDATION LOT 'Standard 18-2) : POTENTIAL' (weight EXPOSURE(2) (Range in Ft.) CATEGORY
1 percent)
25 2 Very Low 0.0055 Negligible 5
:26 ' 2 Very Low . 0.0055 Negligible ' 5-6 . I
27 2 .Very Low 0.0055, Negligible 5-7
28 2 Very Low 0.0055 Negligible 3
" Per Table 18-I-13 of the Unifàrm Building Code' (1997 ed.)
Per Table 19-A-4 of the Uniform Building Code (1997 ed.)
Foundations should be constructed in accordance with recommendations for the specific categories noted '
above and'presented in Table 3. ' . .
--.--- --.------- .,,,- -. .- .. -w. "W' -w.:W -w - --- -•-'. - -
TABLE 3
CONVENTIONAL PERIMETER FOOTINGS, SLABS, AND EXTERIOR FLATWORK
FOR CALAVERA HILLS, VILLAGE T
MINIMUM INTERIOR EXTERIOR
FOUNDATION FOOTING SLAB REINFORCING INTERIOR SLAB UNDER-SLAB GARAGE SLAB FLATWORK
CATEGORY SIZE THICKNESS STEEL REINFORCEMENT TREATMENT REINFORCEMENT REINFORCING
12" Wide 4 " Thick 1- #4 Bar Top #3 Bars @ 2' Sand Over 6" x 6" None
x and Bottom 24' o.c. 10-Mil Polyvinyl (10/10)
12" Deep Both Directions Membrane Over WWF
2" Sand Base
II 12' Wide 4 "Thick 2- #4 Bars Top #3 Bars @ 2" Sand Over 6" X 6" : 6" X 6"
X. and Bottom 18"o.c. 10-Mil Polyvinyl 1 (6/6) (10/10)
18" Deep Both Directions Membrane Over WWF I WWF
2" Sand Base
III 12" Wide 4" Thick 2- #5 Bars Top 43 Bars @ 2" Sand Over Same as 6" x 6"
x and Bottom 18" o.c. 10-Mil Polyvinyl Interior Slab (6/6)
24" Deep Both Directions Membrane Over WWF
2" Sand Base
Category Criteria
Category I: Max. Fill Thickness is less than 20'.and E.I. is less than or equal to 50 and Differential Fill Thickness is less than 10' (see Note 1).
Category It: Max. Fill Thickness is less than 50' and E.I. is less than or equal to 90 or Differential Fill Thickness is between 10 and 20' (see Note 1).
Category III: Max. Fill Thickness exceeds 59, or E.I. exceeds 90 but is less than 130, or Differential Fill Thickness exceeds 20' (see Note 1).
Notes: 1. PT foundations are required where maximum fill exceeds 50', or the ratio of the maximum fill thickness to the minimum fill thickness exceeds 3:1. Consideration
should be given to using PT foundations where the E.I. exceeds 90.
Footing depth measured from lowest adjacent subgrade.
Allowable soil bearing pressure is 2,000 psf.
Concrete for slabs and footings shall have a minimum compressive strength of 2,000 psi (2,500 psi for exterior flatwork), or adopted UBC minimum, at 28 days,
-using 5 sacks of cement. Maximum Slump shall be 59. •
Visqueen vapor barrier not required under garage slab. However, consideration should be given to future uses of the slab area, such as room conversion and/or
storage of moisture-sensitive materials. •
Isolated footings shall be connected to foundations per soils engineer's recommendations (see report).
Sand used for base under slabs shall be very low expansive, and have SE> 30. • •
8 Additional exterior flatwork recommendations are presented in the text of this report
-9. All slabs should be provided with weakened plane joints to control cracking. Joint spacing should be in accordance with correct industry standards and reviewed
by the project structural engineer. • •
APPENDIX A
REFERENCES
GeoSoils, Inc, 2003a, Memorandum "review of grading and trench backfill
recommendations, Calavera Hills 11, 'Carlsbad Tract 0002, Drawing 390-90, city of.
Carlsbad, San Diego County, California," W.0. 2863-A-SC, dated August 16, 2002,
W.0. 3459-132-SC, May 20
2003b, Memorandum general discussion of fill quality, Calavera Hills II, Carlsbad,
San Diego County, California, W 0 3459-B2-SC, dated May 20
2003c, Revised geotechnical update, Village E-1 of Calavera Hills II, Carlsbad, San
Diego County, California, W 0 3459-B-SC, May 12
2003d, Geotechnical update, Village E-1 of Calavera Hills II, Carlsbad, San Diego
t County, California, W.0. 3459-B-SC, February 17
2002, Review of grading and trench backfill recommendations, Calavera Hills II,
Carlsbad Tract 00-02, Drawing 390-90, City of Carlsbad, San Diego County,
California, W.0. 2863-A-SC, August 16
2000, Update of geotechnical report, Calavera Hills, Village E-1, City of Carlsbad,
California, W.0. 2789-A-SC, August 28
1 998a, Lack of Paleontological Resources, Carlsbad Tract Nos. 83-19, PUD 56, and
83-32, PUD 62,.Carlsbad, San Diego County, California, W.O. 2393-8-SC, dated
January 21
1998b, Preliminary review of slope stability, Calavera Hills, Villages "Q" and
"T", City of Carlsbad, California, W.O. 2393-13SC, dated February 16. . .
1998c, Review of slope stability, Calavera Hills, Villages "Q" and "1," City of
Carlsbad, California, W.0. 2393-B-SC, dated June 24
1998d, Toe Drain Recommendations, Calavera Hills, Village T, City.of Carlsbad,
California, W.0. . 2393-B-SC, dated September 30
Hunsaker & Associates San Diego, Inc., 1997b, Plans, for the grading of Calavera Hills
Village "Q", Carlsbad Tract 83-32, Sheets 1-8, Drawing No 303-2A, Project
No 2.89.33, dated November 17
Southern California Soil and Testing, Inc., 1992, Interim report of as built geology field
observations and relative compaction tests, proposed College Boulevard
Improvements and Village El, Carlsbad, California, SCS&T 9121081
1988, Supplemental soil investigation, Calavera Hills Village Q and'T, College
Boulevard, Carlsbad, California, job no 8821142, report no 1, dated October 6
GeoSoils, Inc.
GeoSoils, Inc.
M. J. Schiff & Associates, Inc.
Consulting Corrosion Engineers - Since 1959 Phone: (909) 626-0967 Fax: (909) 626-3316
431 W. Baseline Road E-mail lab@mjschiff.com
Claremont, CA 91711 website: mjschiff corn
Table 1 - Laboratory Tests on Soil Samples
Calavera Hills
Your #3459-B-SC, MJS&A #03-0625LAB
30-May-03
Village E-1
Village E-1 Village E-1 Lots 22-28,
Lots 1-6, 14 Lots 15-21 Rec.
FG FG FG
Units
ohm-cm 170,000 48,000 35,000
ohm-cm . 2,200 1,600 3,300
Sample ID
Resistivity
as-received
saturated
pH . 6.5 7.3 6.7
Electrical .
Conductivity ms/cm 0.18 0.20 0.13
Chemical Analyses
Cations
calcium Ca 2+mg/kg 40 12 .16
magnesium Mg 2+ mg/kg ND 10 ND
sodium Na mg/kg 75 126 77
Anions
carbonate C032 mg/kg ND ND ND
bicarbonate HC031 mg/kg 67 76 37
chloride Cl'--mg/kg 100 135 85
sulfate S042 mg/kg 64 88 55
Other Tests
ammonium 1+ NH4 mg/kg na na na
nitrate NO3 mg/kg na na na
sulfide S 2-qual na na na
Redox my na na na
Electrical conductivity in millisiemens/cm and chemical analysis were made on a 1:5 soil-to-water extract.
mg/kg = milligrams per kilogram (pans per million) of dry soil.
Redox = oxidation-reduction potential in millivolts
ND = not detected
na = not analyzed
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• Figure B-i