HomeMy WebLinkAboutParcel Map 21766 Parcel 1 Geotech Rough Grading (Aug.2,2005)
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o PETRA
RECEIVED
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OFFICES IN THE COUNTIES OF
ORANGE. SAN DIEGO. RIVERSIDE. LOS ANGELES. SAN BERNA DINO
1\11 r: 3 1 Z005
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ENGINEErm~G Da\l\HTMr:~J
August 2, 2005
J.N.447-05
Messrs. Nasir Ahmed and Aziz Said
MAGESTIC GROUP, INC./AZ WOODWORKING
24909 Madison A venue, Unit 1511
Murrieta, California 92562
Subject:
Geotechnical Report of Rough Grading, Parcel 1 of Parcel
Map 21766, Located on Colver Court, City of Temecula, Riverside
County, California
Dear Messrs. Ahmed and Said:
This report provides a summary of the observation and testing services provided by
Petra Geotechnical, Inc. (Petra) during rough grading of a single-family residential
lot identified as Parcell Parcel Map 21766, located on Colver Court in the City of
Temecula, California. Conclusions and recommendations pertaining to the
suitability of the grading for the proposed residential construction on the subject lot
are provided herein, as well as foundation-design recommendations based on the
as-graded soil conditions.
The purpose of this recent rough-grading phase was to construct a level building
pad for a single-family residence and drive area. Rough grading was performed
during July 2005.
REGULATORY COMPLIANCE
Excavation to grade, over excavations of unsuitable low-density surficial soils and
placement of compacted fill under the purview of this report have been completed
under the observation and with selective testing by Petra.
The earthwork was performed in accordance with the recommendations presented
in the referenced geotechnical report and the grading code of the City ofTemecula.
PETRA GEOTECHNICAL, INC.
41640 Corning Place . Suite 107 . Murrieta . CA 92562 . Tel: (909) 600-9271 . Fax: (909) 600-9215
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MESSRS. AHMED & SAID
PM 21766 Parcellrremecula
August 2, 2005
J.N.447-05
Page 2
The completed earthwork has been reviewed and is considered adequate for the
construction now plarmed. On the basis of our observations, as well as 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 implied nor made.
SUMMARY OF AS-GRADED SOIL AND GEOLOGIC CONDITIONS
As-Graded Conditions
Grading operations within the subject parcel involved the overexcavation of low-
density surficial soils that included topsoil, alluvium and highly weathered bedrock,
as well as bringing the overexcavated areas to design elevations with compacted
fill. A general description of the soil and bedrock units encountered or placed
during rough grading is provided below.
. Engineered Fill (map svmbol afc) - The engineered-fill soils were comprised of
onsite-derived topsoil, alluvium soils and bedrock materials and select imported
soil. The soils consisted typically of fine silty sands and silty sands with clay.
. Bedrock: Temecula Arkose Formation (map svmbol Tta) - Pliocene-age
Temecula Arkose Formation bedrock was encountered in the over excavation
bottoms. This material consisted of fine- to coarse-grained, massive sandstone
and silstone, which were various shades ofbroWll and light grey, slightly moist
to wet, moderately hard to hard and thickly bedded to massive. Structure
appeared to strike northeast-southwest and dip steeply to the south about
60 to 70 degrees.
Groundwater
No groundwater or seepage was encountered during rough-grading operations.
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MESSRS. AHMED & SAID
PM 21766 Parcellrremecula
August 2, 2005
J.N.447-05
Page 3
Faulting
The geologic structure of the southern California area is dominated mainly by
northwest-trending faults associated with the San Andreas system. Faults, such as
the Newport-Inglewood, Whittier, Elsinore, San Jacinto and San Andreas, are
major faults in this system and are known to have ruptured the ground surface in
historic times.
Based on our review of published and unpublished geotechnical maps and literature
pertaining to the site and regional geology, the site is not located within and
Alquist-Priolo Fault Hazard Zone. The closest active faults to the site are the
Elsinore-Temecula fault located approximately 1.1 miles (1.8 kilometers) to the
south and the Elsinore-Julian fault located approximately 10.3 miles (16.5
kilometers) to the southeast. The most significant fault, with respect to anticipated
ground motions at the site, is the Elsinore- Temecula fault, due to its proximity and
large possible magnitude. No active or potentially active faults are known to
project through or toward the site.
SUMMARY OF EARTHWORK
OBSERVATIONS AND DENSITY TESTING
Clearing and Grubbing
Vegetation consisting of weeds and grasses was stripped and removed from the
work area prior to the commencement of rough-grading operations.
Ground Preparation/Remedial Grading
In areas to be graded, existing low-density surficial soils and weathered bedrock
were overexcavated to expose competent bedrock. Exposed bottom surfaces in
overexcavated areas were observed by a representative from Petra prior to placing
fill. Following this observation, the exposed bottom surfaces were scarified to
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MESSRS. AHMED & SAID
PM 21766 Parcellrremecula
August 2, 2005
J.N.447-05
Page 4
depths of approximately 6 to 8 inches, watered or air-dried as necessary to achieve
a moisture content near or slightly above optimum moisture content and then
compacted by rolling with heavy equipment.
Fill Placement and Testing
Fill soils were placed in thin lifts to approximately 6 to 8 inches in thickness,
mechanically mixed to a uniform moisture content and then compacted in-place by
rolling with heavy equipment. Field density testing indicated that fill materials
were compacted to 90 percent or more relative compaction. The vertical depth of
fill placed within the subject site was up to approximately 12 feet.
Field density and moisture content tests were performed in accordance with the
nuclear-gauge methods ASTMs D2952 and D3017. Field density test results
within the subject parcel are presented in the attached Table I and approximate test
locations are shown on the enclosed Geotechnical Map with Density Test Locations
(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 determine moisture
content, in-situ density and relative compaction. When field density tests produced
results less than a relative compaction of 90 percent, the approximate limits of the
substandard fill were established. The substandard area was then either removed or
reworked in-place.
Visual classification of earth materials in the field was the basis for determining
which maximum dry density value was applicable for a given density test.
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MESSRS. AHMED & SAID
PM 21766 Parcellrremecula
August 2, 2005
J.N.447-05
Page 5
CutlFiII Transition
In order to eliminate cut/fill transition within the building area, the shallow fill and
cut portions of the building pad were over excavated to a depth of about 5 feet
below pad grade and brought to design elevation by compacted-fill placement.
SOIL PROPERTIES
Maximum Dry Density
Maximum dry density and optimum moisture content of representative samples of
the fill soils were determined in our laboratory in accordance with ASTM D1557.
The results of these tests are presented in Appendix A.
Expansion Index Test
An expansion index test was performed on a representative sample of soil obtained
near finish-pad grade. This test was performed in accordance with ASTM D4829.
the result is also summarized in Appendix A.
FOUNDATION-DESIGN RECOMMENDAIONTS
Foundation Type
Based on as-graded soil and geologic conditions, the use of conventional shallow-
spread foundations is considered feasible for the proposed residential structure.
Recommended design parameters regarding geotechnical considerations for
conventional shallow-spread foundations are provided herein.
Allowable Soil-Bearing Values
An allowable-bearing value of 1,500 pounds per square foot (pst) may be used for
24-in square pad footings and 12-inch wide continuous footings founded at a depth
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MESSRS. AHMED & SAID
PM 21766 Parcellrremecula
August 2, 2005
J.N.447-05
Page 6
of 12 inches or more below the lowest adjacent final grade. This value may be
increased by 20 percent for each additional foot of width and depth, to a value of
2,500 psf. Recommended allowable-bearing values include both dead and live
loads and may be increased by one-third for short-duration wind and seismic
forces.
Settlement
Based on the general settlement characteristics of the compacted fill and in-situ
bedrock, as well as the anticipated loading, it has been estimated that the total
settlement of building footings will be less than approximately I inch. Differential
settlement is estimated to be about 1/2 inch over a horizontal distance of 40 feet. It
is anticipated that the majority of the settlement would occur during construction or
shortly thereafter as building loads are applied.
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. The above
values may be increased by one-third when designing for short-duration wind or
seismic forces. In addition, a coefficient of friction of 0.4 times the dead-load
forces may be used between concrete and the supporting soils to determine lateral
sliding resistance. The above values are based on footings placed directly against
compacted fill or bedrock. In the case where footing sides are formed, the backfill
placed against the footings should be compacted to 90 percent or more of
maximum dry density.
Footing Observations
Building-footing trenches should be observed by the project geotechnical
consultant to document that they have been excavated into competent-bearing soils.
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MESSRS. AHMED & SAID
PM 21766 Parcellrremecula
August 2, 2005
J.N.447-05
Page 7
The foundation excavations should be observed prior to the placement of forms
reinforcement or concrete. The excavations should be trimmed neat, level and
square. 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-ground areas unless the soils are compacted to 90 percent or more
of maximum dry density.
Structural Setbacks from Descending Slopes
Where structures are proposed near the top of descending slopes, the footing
setback from the slope face should conform with the 2001 California Building
Code (CBC) Figure 18-1-1. The required setback is Hl3 (one-third the slope
height) measured along a horizontal line projected from the lower outside face of
the footing to the slope face. The footing setback should be 5 feet or more where
the slope height is 15 feet or less and vary up to 40 feet where the slope height
exceeds 15 feet.
Expansive Soil Considerations
Result of a laboratory test indicates onsite and import soils exhibit a VERY LOW
expansion potential as classified in accordance with the 2001 CBC Table 18-1-1.
Design and construction recommendations for very low expansion potential are
provided below.
Verv Low Expansion Potential (Expansion Index of 20 or less)
The results of our laboratory tests indicate that onsite soils exhibit VERY LOW
expansion potential as classified in accordance with the 2001 CBC, Table 18-1-B.
For this condition, it is recommended that footings and floors be constructed and
reinforced in accordance with the following criteria. However, additional slab
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MESSRS. AHMED & SAID
PM 21766 Parcellrremecula
August 2, 2005
J.N.447-05
Page 8
thickness, footing Sizes and/or reinforcement may be required by the project
architect or structural engineer.
. Footings
_ Standard depth footings may be used with respect to building code
requirements for the planned construction (i.e., 12 inches deep for one-story
construction and 18 inches deep for two stories). Interior continuous footings
may be founded at a depth of 12 inches or greater below the top-of-slab.
_ Continuous footings should have a width of 12 and 15 inches or greater for one-
and two-story buildings, respectively, and should be reinforced with two No.4
bars, one top and one bottom.
Isolated interior pad footings should be 24 inches or more square and
reinforced in accordance with the structural engineer's recommendations.
Interior isolated footings may be founded 12 inches or more below top-of-slab.
_ Exterior pad footings intended for the support of roof overhangs, such as
second-story decks, patio covers and similar construction, should be 24 inches
square or greater and founded at a depth of 18 inches or greater below the
lowest adjacent final grade. The pad footings should be reinforced in
accordance with the structural engineer's recommendations.
. Floor Slabs
_ Living-area concrete-floor slabs should be 4 inches or more thick and
reinforced with either 6x61W1.4xW1.4 welded-wire mesh or with No.3 bars
spaced 24 inches or less on-centers, both ways. Slab reinforcement should be
properly supported so that the placement is near mid-depth.
_ Living-area concrete-floor slabs should be underlain with a moisture-vapor
retarder consisting of 10-mil polyethylene membrane or equivalent. Laps
within the membrane should be sealed and 2 inches or more of clean sand be
placed over the membrane to promote uniform curing of the concrete.
Garage-floor slabs should be 4 inches or more thick and placed separately from
adjacent wall footings with a positive separation maintained with 3/8 inch 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
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MESSRS. AHMED & SAID
PM 21766 Parcellrremecula
August 2, 2005
IN. 447-05
Page 9
provided across garage entrances. The grade beam should be reinforced with
two No.4 bars, one top and one bottom.
_ Prior to placing concrete, sub grade soils should be thoroughly moistened to
promote uniform curing of the concrete and reduce the development of
shrinkage cracks.
Seismic-Desil!n Considerations
Ground Motions
The site will probably experience ground shaking from moderate- to large-size
earthquakes during the life of the proposed development. Furthermore, it should be
recognized that the southern California region is an area of high seismic risk and
that it is not considered feasible to make structures totally resistant to seismic-
related hazards.
Structures within the site should be designed and constructed to resist the effects of
seismic ground motions as provided in the 2001 CBC Sections 1626 through 1633.
The method of design is dependent on the seismic zoning, site characteristics,
occupancy category, building configuration, type of structural system and on the
building height.
For structural design in accordance with the 2001 CBC, a computer program
developed by Thomas F. Blake (UBCSEIS, 1998/1999) was utilized which
compiles fault information for a particular site using a modified version of a data
file of approximately 150 California faults that were digitized by the California
Geological society and the U.S. Geological Survey. This program computes
various information for a particular site including the distance of the site from each
of the faults in the data file, the estimated slip-rate for each fault and the "maximum
moment magnitude" of each fault. The program then selects the closest Type A,
Type B and Type C faults from the site and computes the seismic design
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MESSRS. AHMED & SAID
PM 21766 Parcellrremecula
August 2, 2005
J.N.447-05
Page 10
coefficients for each of the fault types. The program then selects the largest of the
computed seismic design coefficients and designates these as the design
coefficients for the subject site.
Based on our evaluation, the Elsinore- T emecula fault, located south of the site
would probably generate the most severe site ground motions with an anticipated
maximum moment magnitude of 6.8 and anticipated slip rate of 5 mm/year. The
following the 2001 CBC seismic design coefficients should be used for the
proposed structures. These criteria are based on the soil profile type, either
compacted artificial fill or bedrock, as determined by existing subsurface geologic
conditions, on the proximity of the Elsinore- T emecula fault and on the maximum
moment magnitude and rate.
Figure 16-2 Seismic Zone 4
Table 16-1 Seismic Zone Factor Z 0.40
Table 16-U Seismic Source Type B
Table 16-J Soil Profile Type Sc
Table 16-S Near-Source Factor, Na 1.3
Table 16- T Near-Source Factor, Nv 1.6
Table 16-Q Seismic Coefficient, C. 0.52
Table 16-R Seismic Coefficient, Cv 0.90
Secondarv Effects of Seismic Activity
Secondary effects of seismic activity normally considered as possible hazards to a
site include several types of ground failure, as well as induced flooding. Various
general types of ground failures which might occur as a consequence of severe
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MESSRS. AHMED & SAID
PM 21766 Parcellrremecula
August 2, 2005
J.N.447-05
Page II
ground shaking at the site, including landsliding, ground subsidence, ground
lurching, shallow-ground rupture and liquefaction. The probability of occurrence
of each type of ground failure depends on the severity of the earthquake, distance
from faults, topography, subsoils and groundwater conditions, in addition to other
factors. The above secondary effects of seismic activity are considered unlikely at
the site.
Seismically induced flooding which might be considered a potential hazard to a site
normally includes flooding due to a tsunami (seismic sea wave), a seiche (i.e., a
wave-like oscillation of the surface of water in an enclosed basin that may be
initiated by a strong earthquake) or failure of a major reservoir or retention
structure upstream ofthe site. No such conditions exist at the subject site.
Corrosion
The corrosion potential of the onsite materials was evaluated for its effect on steel
and concrete. The corrosion potential was evaluated using the results of laboratory
tests on a representative sample obtained during our field exploration. Laboratory
testing was performed to evaluate pH, minimum electrical resistivity and chloride
and soluble sulfate content.
The test results indicate that pH of the sample of soil tested was 6.9. A measured
electrical resistivity of 8,900 ohm-em indicated that the site soils may be
considered non-corrosive to ferrous materials. However, consideration should be
given to using plastic piping instead of metal.
Testing further indicates a soluble sulfate content of 0.0082 percent and a chloride
content of 125 ppm. We recommend that Type II modified cement be used and
that a 3-inch thick concrete cover be maintained over the reinforcing steel in
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MESSRS. AHMED & SAID
PM 21766 Parcellrremecula
August 2, 2005
J.N.447-05
Page 12
concrete in contact with the soil. A corrosion engineer can be consulted to provide
additional recommendations if desired.
Retaining Walls
Footinl!: Embedments
The base ofretaining-wall footings constructed on level ground may be founded at
a depth of 12 inches or more below the lowest adjacent final grade. Where
retaining walls are proposed on or within 15 feet from the top of an adjacent
descending fill slope, the footings should be deepened such that a horizontal
clearance of Hl3 or more (one-third the slope height) is maintained between the
outside bottom edges of the footings and the face of the slope but not to exceed 12
feet, and not less than 7 feet. This horizontal structural setback may be reduced to
10 feet where footings are constructed near the tops of descending cut slopes. The
above-recommended footing setbacks are preliminary and may be revised based on
site-specific soil and/or bedrock conditions.
Footing trenches should be observed by the project geotechnical representative to
document that the footing trenches have been excavated into competent-bearing
soils and/or bedrock and to the embedments recommended above. These
observations should be performed prior to placing forms or reinforcing steel.
Active Earth Pressures
An active lateral-earth pressure equivalent fluid having a density of 35 pounds per
cubic foot (pcf) should tentatively be used for design of cantilevered walls retaining
a drained, level backfill. Where the wall backfill slopes upward at 2: I
(horizontal:vertical [h:v]), the above value should be increased to 52 pcf. Retaining
walls should be designed to resist surcharge loads imposed by other nearby walls,
structures, or vehicles in addition to the above active earth pressures.
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MESSRS. AHMED & SAID
PM 21766 Parcellrremecula
August 2, 2005
J.N.447-05
Page 13
Drainaee
Weepholes or open vertical masonry joints should be provided in retaining walls
less than 6 feet in height to reduce the likelihood of entrapment of water in the
backfill. Weepholes, if used, should be 3 inches or more in diameter and provided
at intervals of 6 feet or less along the wall. Open vertical masonry joints, if used,
should be provided at 32-inch or less intervals. A continuous gravel fill, 12 inches
by 12 inches, should be placed behind the weepholes or open masonry joints. The
gravel should be wrapped in filter fabric to reduce infiltration of fines and
subsequent clogging of the gravel. Filter fabric may consist of Mirafi 140N or
equivalent.
In lieu of weepholes or open joints, a perforated pipe-and-gravel subdrain may be
used. Perforated pipe should consist of 4-inch or more diameter PVC Schedule 40
or ABS SDR-35, with the perforations laid down. The pipe should be embedded in
1.5 cubic feet per foot of 0.75- or 1.5-inch open-graded gravel wrapped in filter
fabric. Filter fabric may consist of Mirafi 140N or equivalent.
Retaining walls greater than 6 feet high should be provided with a continuous
backdrain for the full-height of the wall. This drain could consist of a geosynthetic
drainage composite, such as Miradrain 6000 or equivalent or a permeable drain
material placed against the entire backside of the wall. If a permeable drain
material is used, the backdrain should be 1 or more feet thick. Caltrans Class II
permeable material or open-graded gravel or crushed stone (described above) may
be used as permeable drain material. If gravel or crushed stone is used, it should
have less than 5 percent material passing the No. 200 sieve. The drain should be
separated from the backfill with a geofabric. The upper I foot of the backdrain
should be covered with compacted fill. A drainage pipe consisting of 4-inch
diameter perforated pipe (described above) surrounded by I cubic foot per foot of
gravel or crushed rock wrapped in a filter fabric should be provided along the back
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MESSRS. AHMED & SAID
PM 21766 Parcellffemecula
August 2, 2005
J.N.447-05
Page 14
of the wall. The pipe should be placed with perforations down, sloped at 2 percent
or more and discharge to an appropriate outlet through a solid pipe. The pipe
should outlet away from structures and slopes. The outside portions of retaining
walls supporting backfill should be coated with an approved waterproofing
compound to inhibit infiltration of moisture through the walls.
Temporarv Excavations
To facilitate retaining-wall construction, the lower 5 feet of temporary slopes may
be cut vertical and the upper portions exceeding a height of 5 feet should be cut
back at a gradient of 1:1 (h:v) or less for the duration of construction. However,
temporary slopes should be observed by the project geotechnical consultant for
evidence of potential instability. Depending on the results of these observations,
flatter slopes may be necessary. The potential effects of various parameters, such
as weather, heavy equipment travel, storage near the tops of the temporary
excavations and construction scheduling, should also be considered in the stability
of temporary slopes.
Wall Backfill
Retaining-wall backfill should be placed in 8-inch loose lifts, watered or air-dried
as necessary to achieve near-optimum moisture conditions and compacted in-place
to a relative compaction of90 percent or more based on ASTM D1557.
Masonrv Garden Walls
Construction on or Near the Tops of Descendinl!: Slopes
Continuous footings for masonry garden walls proposed on or within 5 feet from
the top of descending cut or fill slopes should be deepened such that a horizontal
clearance of 7 feet or more is maintained between the outside bottom edge of the
footing and the slope face. The footings should be reinforced with two No.4 bars
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MESSRS. AHMED & SAID
PM 21766 Parcellrremecula
August 2, 2005
J.N.447-05
Page 15
or more, one top and one bottom. Plans for top-of-slope garden walls proposing
pier and grade-beam footings should be reviewed by the project geotechnical
consultant prior to construction.
Construction on Level Ground
Where masonry walls are proposed on level ground and 7 feet or more from the
tops of descending slopes, the footings for these walls may be founded at a depth of
12 inches or more below the lowest adjacent final grade. These footings should
also be reinforced with two No.4 bars, one top and one bottom.
Construction Joints
In order to mitigate the potential for unsightly cracking related to the effects of
differential settlement, positive separations (construction joints) should be provided
in the walls at horizontal intervals of approximately 25 feet and at each corner. The
separations should be provided in the blocks only and not extend through the
footings. The footings should be placed monolithically with continuous rebars to
serve as effective grade beams along the full lengths ofthe walls.
Concrete Flatwork
Thickness and Joint Spacing
To reduce the potential of unsightly cracking, concrete sidewalks and patio-type
slabs should be 4 inches thick or more provided with construction or expansion
joints every 6 feet or less. Concrete driveway-slabs should be 4 inches thick or
more and provided with construction or expansion joints every 10 feet or less.
Subl!:rade Preparation
As a further measure to reduce cracking of concrete flatwork, the subgrade soils
below concrete-flatwork areas should first be compacted to a relative density of 90
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MESSRS. AHMED & SAID
PM 21766 Parcellrremecula
August 2, 2005
J.N.447-05
Page 16
percent or more and then thoroughly wetted to achieve a moisture content that is
equal to or slightly greater than optimum moisture content. This moisture should
extend to a depth of 12 inches or more below subgrade and maintained in the soils
during placement of concrete. Pre-watering of the soils will promote uniform
curing of the concrete and reduce the development of shrinkage cracks. A
representative of the project geotechnical consultant should observe and document
the density and moisture content of the soils and the depth of moisture penetration
prior to placing concrete.
Planters
Area drains should be extended into planters that are located within 5 feet of
building walls, foundations, retaining walls and masonry block walls to reduce
excessive infiltration of water into the adjacent foundation soils. The surface of the
ground in these areas should also be sloped at a gradient of 2 percent or more away
from the walls and foundations. Drip-irrigation systems are also recommended to
prevent overwatering and subsequent saturation of the adjacent foundation soils.
POST -GRADING OBSERVATIONS AND TESTING
Petra should be notified at the appropriate times in order that we may provide the
following observation and testing services during the various phases of post
grading construction.
. Building Construction
_ Observe footing trenches when first excavated to document adequate depth
and competent soil-bearing conditions.
_ Observe 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.
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MESSRS. AHMED & SAID
PM 21766 Parcellrremecula
August 2, 2005
J.N.447-05
Page 17
_ Observe pre-soakjng of subgrade soils below living-area and garage floor
slabs to document moisture content and penetration.
. Exterior Concrete- Flatwork Construction
_ Observe and test sub grade soils below all concrete- flatwork areas to
document adequate compaction and moisture content.
. Utility-Trench Backfill
_ Observe and test placement of all utility-trench backfill to document
adequate compaction.
. Re-Grading
_ Observe and test placement of fill to be placed above or beyond the grades
shown on the approved grading plans.
This opportunity to be of service IS sincerely appreciated. If you have any
questions, please contact this office.
Respectfully submitted,
WC/GRW/JAL/ms/kec
Attachments: References
Distribution: (5) Addressee
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REFERENCES
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Alpine Consullants Inc., 2003, "Grading Plan," dated March 15,2003, Sheels I and 2, unsigned.
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Blake, T.F., 1998/1999, UBCSEIS, Version 1.03, A Compuler Program for the Estimation of Uniform Building
Code Coefficients Using 3-D Faull Sources.
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, 2000, FRISKS?, Version 4.00, A Computer Program for the Probabilislic Estimation of Peak
Acceleralion and Uniform Hazard Spectra Using 3-D Faults as Earthquake Sources.
Hart, Earl W. and Bryant, William A., 1997, Fault-Rupture Hazard Zones in California, CDMG Special
Publicalion 42, revised 1997, Supplemenls I and 2 added ]990.
International Conference of Building Officials, 1997, Uniform Building Code, Structural Engineering Design
Provisions.
I
,1998, Maps of Known Active Fault Near-Source Zones in California and Adjacent Portions of Nevada,
Prepared by California Division of Mines and Geology.
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Jenkins, OlafP., 1966, Geologic Map of California, Santa Ana Sheet, Scale: 1:250,000.
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Jennings, C.W., 1985, An Explanalory Texl 10 Accompany !he 1:750,000 scale Faull and Geologic Maps of
California, California Division of Mines and Geology.
. 1994, Fault AClivity Map of California and Adjacenl Areas, Scale 1:750,000.
Kennedy, M.P., 1977, Recency and Characler of Faulting Along the Elsinore Faull Zone in Southern Riverside
County, California, CDMG Special Report 13 I.
Morton, D.M., 1999, Preliminary DigilaI Geologic Map of the Sanla Ana 30'X60' Quadrangle, Southern
California, Open File Report OF99-172.
I
Petra Geotechnical, Inc., 2004 a, Onsile Sewage-Disposal Feasibility Invesligalion, Proposed Single-Family
Residence, Parcel I of Parcel Map 2 I 766, Located on Colver Court, City of Temecula, Riverside County,
California,[or Sharon & Bruno Lebon, J.N. 327-04, daled June 8.
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,2004 b, Geolechnical Invesligation, Proposed Single-Family Residence, Parcel Map 21766, Located on
Colver Court, City of Temecula , Riverside California, for Sharon & Bruno Lebon, J.N. 327-04, dated
June 16.
Weber, F.H., Jr., 1977, Seismic Hazards Related to Geologic Factors, Elsinore and Chino Fault Zones, Northwestern
Riverside County, Califomia, CDMG Open File Report 77-4 LA, May, 1977.
PETRA GEOTECHNIAL, INC.
J.N. 447-05
AUGUST 2005
Vb
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TABLE I
Field Density Test Results
tliSt
D.......t..
)(#
......... ..
......... ..
....-..... ..
.." "'-",' ..
. ...... ..
.... .... ..
......... -
..-_..... ..
........-. ..
.......,...,.,..,. ....
" ....... ..
....-.-.....-..-. ,",
... t~f... )
...... . ,.
........ ..
Nil? )
........,-............,.......,............. "," ......
..........-........... ,. ..
,:,.;.;.:.:.:.,.:.:-:-:-:-:.:.;.:.,,:.:.,.,. .,. .:-:.:
.-...,.,.....................,.,.......... "." ......
.:..:-:..,.:-:.:.:.;.:.:.:.:.:-:-:.;.;.;.:.:.: ,.: ,.:.:.
. . ........,......,... . ,'"
......,........-........................... '." .....
.t~$fL6caHij.rt) ... .....
,................ ....
..... ............
~!~t;,
{ft)
:-:...,',.:.....
....-....
........'.
......-..-.
..... . .
.........
........-.........
:-:,;.;.:.:.;.:.:
...........'........
M&iSt
.........
................-.
.........
(%l
.........
...............
..,..... ......
...-..........
.,............-..
.....,...-.-.....-......,..
.....-,.....................
.,...-......,..
. . . , . . . . . . . . . . . . . . . . . . . . . . .. . .
............ .
............-...
............ .
ptyp~*~
. . . . . . . . . . . . . . '. .............
.........(. ......1)......
.... C. ....
............p............
..... .....
.......,...-..-.
RC
(%)
:::;:::::::::::;::::::;::;;;> ::::::::::::;:;::;:;:::::
....,.:.:,:-:-:.:.:.:-:.;.:.:., :,::::::;:,::::::::;:,::.
.::;:;:::::::::,:;:::::::;,::;. '::::::::::::':':;:::::;'
~#%~~tS#il.......
......................................'...p......c.......................... .........~pe....
, ~J .......~'" .........
07/11/05 1 Pad 120.5 7.8 125.2 95 131.5 1
07/11/05 2 Pad 121.5 6.5 122.6 93 131.5 1
07/11/05 3 Pad 126.4 9.0 125.2 93 134.0 2
07111/05 4 Pad 124.4 9.6 127.7 95 134.0 2
07/11/05 5 Pad 129.4 7.5 126.5 94 134.0 2
07/13/05 6 Pad 131.0 11.5 123.2 92 134.0 2
07113/05 7 Pad 131.5 12.0 121.1 90 134.0 2
07/18/05 8 Pad 131.5 9.2 122.0 93 131.5 I
07/19/05 9 Pad 134.5 11.9 121.9 93 131.5 1
07/19/05 10 Pad 134.5 12.1 120.1 91 131.5 1
07/19/05 11 Garage area center 134.5 11.1 122.1 93 131.5 1
PETRA GEOTECHNICAL, INC.
J.N.447-05
PM 21766 Parcell
AUGUST 2005
TABLE T-Il ~
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I APPENDIX A
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I LABORATORY TEST CRITERIA
I LABORATORY TEST DATA
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I e PETRA
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APPENDIX A
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Laboratory Test Criteria
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Laboratorv Maximum Drv Densitv
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Maximum dry densily and oplimum moisture conlenl were delermined for seiecled samples of soil in accordance
with ASTM D1557. Pertinenilest values are given on Plale A-I.
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Expansion Index
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Expansion index tests was performed on a selecled sample of soil in accordance wilh ASTM D4829. Expansion
pOlenlial classification was delermined from the 2001 CBC Table 18-I-B on the basis of the expansion index
value. The test resull and expansion potenlial are presenled on Plate A-I.
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Corrosion Test
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Chemical analyses were performed on a selected sample of onsile soil 10 delermine concenlrations of soluble
sulfale and chloride, as well as pH and resistivily. This lesl was performed in accordance with California Tesl
Method Nos. 417 (sulfate), 422 (chloride) and 643 (pH and resislivily). Tesl resull is included on Plate A-I.
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PETRA GfOTfCHNIAL, INC.
J.N. 447-05
AUGUST 2005
'2;\
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LABORATORY MAXIMUM DRY DENSITY
1
2
Fine-Coarse Silty Sand
Fine-Medium Silly Sand
8.0
8.0
131.5
134.0
EXPANSION INDEX TEST DATA
CORROSION TEST
(1) PER ASTM 01557
(2) PER ASTM 04829
(3) PER 2001 CBC Table 18-I-B
(4) PER CALIFORNIA TEST METHOD NO. 417
(5) PER CALIFORNIA TEST METHOD NO. 422
(6) PER CALIFORNIA TEST METHOD NO. 643
(7) PER CALIFORNIA TEST METHOD NO. 643
PETRA GEOTECHNIAL, INC.
J.N. 447-05
AUGUST 2005
Plate A-I
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