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PETRA
OFFICES THROUGHOUT SOUTHERN CALIFORNIA
1 May 9, 2003
J.N. 111-03
CENTEX HOMES
2280 Wardlow Circle, Suite 150
Corona, California 92880 •
' Attention: Mr. Steve Alford
' Subject: Geotechnical Report of Rough Grading, Tournament II at Redlzawk,
Lots 1 through 43, Tract 29734, Temecula Area, Riverside County,
California
This report presents a summary of the observation and testing services provided by
Petra Geotechnical, Inc. (Petra) during the completion of rough-grading operations of
Tract 29734 located in the Temecula area of Riverside County, California. The site
was mass-graded in early 2002 under the observation and testing by Petra (Petra,
' 2002a). Conclusions and recommendations pertaining to the suitability of the grading
for the proposed residential construction are provided herein, as well as foundation-
design recommendations based on the as-graded soil conditions.
REGULATORY COMPLIANCE
Cuts, removals and compaction of unsuitable low-density surface soils, lot
overexcavations and placement of compacted fill under the purview of this report have
' been completed under the observation of and with selective testing by Petra. The
earthwork was performed in accordance with the recommendations presented in
previous geotechnical reports by Petra (see References) and the grading code of the
County of Riverside.
' The completed earthwork has been reviewed and is considered adequate for the
construction now planned. On the basis of our observations, as well as field and
pe 02 239
' PETRA GEOTECHNICAL, INC.
41640 Corning Place . Suite 107 . Murrieta . CA 92562 . Tel: (909) 600-9271 . Fax: (909) 600-9215
CENTEX HOMES May 9, 2003
TR 29734/Temecula Area J.N. 111-03
Page 2
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
' The site was originally mass-graded in January through March 2002 (Petra, 2002a).
At that time removal of unsuitable soils, construction of a canyon drain and
construction of a fill slope ascending from Via La Colorada were performed. Finish-
' grading operations began in July 2002 and included lot overexcavations, construction
of slopes within the tract. Finish-grading operations were completed in April 2003.
Local Geology
' Geologic units exposed within the subject site consisted of alluvium, colluvium and
Quaternary Pauba Formation bedrock. Compacted artificial fill overlies Pauba
' Formation bedrock within the a majority of the site. Cuts exposing Pauba Formation
sandstone exist within Lot 18 and slopes along the eastern portion of the site.
' • Compacted Artificial Fill (map symbol afc) -- Artificial fill materials consisted of
' locally derived sands, silty sands, silts and clays generated by rough grading of the
site and adjacent areas.
' • Quaternary Alluvium (no map symbol) --Alluvium was encountered within valley
and canyon areas within the site and consisted of brown silty sands with variable
amounts of gravel and cobbles. The alluvium was dry to moist and loose to
medium dense. Alluvium was removed and utilized as fill material within the site.
• Quaternary Colluvium (_no map symbol) -- Quaternary colluvium was encountered
' along the flanks of hills and in the upper reaches of canyons to a general depth of
3 feet. It consisted of brown to reddish brown clayey and silty sands which were
dry, loose to medium dense and moderately to abundantly porous. Clay
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CENTEX HOMES May 9, 2003
TR 29734/Temecula Area J.N. 111-03
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cementation resulted in a blocky soil structure. Colluvium was removed and
' utilized as fill material to expose the underlying bedrock.
• Quaternary Pauba Formation Bedrock (map symbol Ops) -- Pauba Formation
' bedrock underlies the entire site at depth and formed the hills within the site prior
to grading. The unit consists of well-graded to silty sandstones with occasional
cobble and 0.5- to 3-foot thick silt and clay beds.
' Geologic Structure
The entire site is underlaid by Pauba Formation sandstone. The bedding typically
trends N50E to N85E and dips 45 to 65 degrees to the southeast. Several fault and
geologic studies have been performed within the vicinity of Tract 29734, due to the
' proximity of the Elsinore fault zone, and subtle topographic expressions observed
during aerial-photograph reviews. The geologic phenomena in this area has been
previously attributed to slope instability associated with landsliding and creep
(Kennedy, 1977; and Petra, 1987, 1989). However, no evidence of slope movement
was encountered during rough-grading operations on the site. The rough grading
exposed bedrock which was faulted by several N4OW right-stepping enechelon faults
' which displaced siltstone and claystone beds from a few inches to 14 feet right-
laterally. Several isolated and discontinuous north- to northeast-trending left-lateral
faults were observed to be offset by the northwest-trending faults. Detailed geologic
mapping is presented on the enclosed Plates 1 and 2. Based on geologic observations
made during rough grading and an additional aerial-photograph review, it appears that
' the tract is underlain by a pressure ridge associated with the Elsinore fault zone. Due
to the extremely subtle surficial expression of the feature observed during the aerial
' photograph review and the lack of soil displacement observed during Petra's
investigations (1987 and 1989) and during grading, the faulting within Tract 29734 is
' older than 11,000 years and is, therefore, not considered active. However, due to the
presence of faulting within Quatemary sediments (Pauba Formation bedrock) and the
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CENTEX HOMES May 9, 2003
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ongoing tectonic activity within the area, the nearby faults should be considered
potentially active. No setbacks or restricted use zones are recommended within
Tract 29734.
' SUMMARY OF EARTHWORK
OBSERVATIONS AND DENSITY TESTING
Clearing and Grubbing
At the time of mass grading, a majority of the tract was covered with a moderate
growth of weeds and shrubs. This vegetation was removed during overexcavation of
' natural grades. Vegetation did not develop prior to the commencement of finish-
grading operations; therefore, clearing and grubbing were not performed prior to
finish-grading operations.
' Ground Preparation
Prior to placing structural fill, existing low-density surficial soils were first removed
' to competent unweathered bedrock. Removals throughout the tract varied from
approximately 3 to 10 feet.
Prior to placing fill, exposed bottom surfaces in removal areas were first observed by
1 our project geologist or senior soil technician. Following this observation, the exposed
bottom surfaces were scarified to depths of approximately 6 to 8 inches,watered or air-
dried as necessary to achieve a moisture content equal or slightly above or below
optimum moisture content and then compacted in-place to a relative compaction of
' 90 percent or more.
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CENTEX HOMES May 9, 2003
TR 29734/Temecula Area J.N. 111-03
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Canyon Subdrains
A canyon subdrain was placed within Lots 5 through 8 where the depth of structural
' fill exceeded 15 feet. The upper end of the subdrain was constructed at an elevation
of 1,179 feet mean sea level (msl) within Lot 5 and terminated at an elevation of 1,155
' msl within Lot 8 where it tied into an existing subdrain. The subdrain consisted of 6-
or 8-inch diameter PVC pipe with perforations placed down. The pipe was encased
' in 0.75 inch gravel, which was wrapped in filter fabric (Mirafi 140 or equivalent). The
subdrain location is on Plates 1 and 2.
Lot Overexcavations
To mitigate distress to residential structures related to the potential adverse effects of
excessive differential settlement, the cut portion of cut/fill transition lots were
' overexcavated to a depth of 3 feet or more below finish grade and replaced with
compacted fill. Several lots exposed steeply dipping clay shear zones in the bedrock.
' The clay observed in the shear zones was considered to be highly expansive and varied
in thickness from less than 0.25 inch to as much as 4 inches in isolated areas. These
tlots were overexcavated to depths of 4 to 6 feet.
Fill Placement and Testing
' Fill soils were placed in lifts restricted to approximately 6 to 8 inches in loose
thickness, watered or air-dried as necessary to achieve near-optimum moisture
' conditions and then compacted in-place to a relative compaction of 90 percent or more
based on ASTM D1557. Compaction was typically achieved by wheel-rolling with an
' 824 rubber-tired dozer and loaded scrapers. The maximum depth of fill placed within
the subject tract is approximately 40 feet.
Field density and moisture content tests were performed in accordance with nuclear-
, gauge test methods ASTM D2922 and D3017. Occasional field density tests were also
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CENTEX HOMES May 9, 2003
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Page 6
performed in accordance with the sand-cone method ASTM D1556. Field density test
' results are presented on the attached Table II (mass grading) and Table III (finish
' grading) and approximate test locations are shown on the enclosed Field Density Test
Location/Geotechnical Maps (Plates 1 and 2).
Field density tests were taken at vertical intervals of approximately 1 to 2 feet and the
compacted fills were tested at the time of placement to document that the specified
' moisture content and recommended relative compaction of 90 percent or more had
' been achieved. Approximately one in-place density test was taken for each 1,000
cubic yards of fill placed and/or for each 2 feet in vertical height of compacted fill.
The actual number of tests taken per day varied with the project conditions, such as the
number of earthmovers (scrapers) and availability of support equipment. When field
1 density tests produced results less than the recommended relative compaction of 90
•
percent or more or if the soils were found to be excessively above or below optimum
' moisture content, 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. Single-point
checks were performed to supplement visual classification.
' Fill Slopes
Fill slopes were constructed at a ratio of 2:1 (horizontal:vertical [h:v]) and to a height
' of approximately 27 feet or less. Fill slopes were overfilled an average of 4 to 5 feet
during construction and then trimmed back to the compacted core. Finished fill slopes
are considered to be both grossly and surficially stable.
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Cut Slopes
Cut slopes were excavated to a height of 24 feet or less at an inclination of 2:1 (h:v)
or gentler. Cut slopes exposed well-graded to silty sandstones, siltstones and
claystones of the Pauba Formation. Geologic structure within the bedrock is not
anticipated to adversely effect the stability of the slopes. The finished cut slopes are
considered both grossly and surficially stable.
I
LABORATORY TESTING
' Maximum Dry Density
' Maximum dry density and optimum moisture content for each significant change in
soil type observed during grading were determined in our laboratory in accordance
with ASTM D1557. Pertinent test values are summarized in Appendix A.
Expansion Index Tests
Expansion index tests were performed on representative samples of soil existing at or
near finish-pad grade within the subject lots. These tests were performed in
accordance with ASTM D4829. Test results are also summarized in Appendix A.
Soluble Sulfate Analyses
' Soluble sulfate analysis were determined for representative samples of soil existing at
t or near finish grade within the subject lots. These tests were performed in accordance
with California Test Method (CTM) No. 417. Test results are summarized in
Appendix A.
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CENTEX HOMES May 9, 2003
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Chloride. Resistivity and pH Analysis
' Water-soluble chloride concentration, resistivity and pH were determined for selected
samples in accordance with CTM Nos. 422 (chloride) and 643 (resistivity and pH).
The results of these analyses are summarized in Appendix A.
FOUNDATION-DESIGN RECOMMENDATIONS
Foundation Types
' Based on as-graded soil and geologic conditions, the use of conventional slab-on-
ground foundations is considered feasible for the majority of the proposed residential
' structures. Isolated lots are underlain by steeply dipping clay shear zones in the
bedrock and will require post-tensioned slab foundations. Recommended design
' parameters are provided herein.
' Allowable Soil-Bearing Capacities
' An allowable soil-bearing capacity of 1,500 pounds per square foot (psi) may be used
for 24-inch square pad footings and 12-inch wide continuous footings founded at a
' depth of 12 inches below the lowest adjacent final grade. This value may be increased
by 20 percent for each additional foot of width or depth, to a value of 2,500 psf.
Recommended allowable soil-bearing values include both dead and live loads and may
be increased by one-third when designing for short-duration wind and seismic forces.
Anticipated Settlement
• Lots 3 through 29, 31,34 and 35 -- Based on the general settlement characteristics
of the compacted fill soils, as well as the anticipated loading, it has been estimated
that the settlement of building footings will be less than approximately 3/4 inch
' where the fill thickness if 10 feet or less. Where the fill thickness exceeds 10 feet,
the settlement is estimated to be 1 inch. Considering the range in compacted fill
depths across the building sites, differential settlement over a horizontal distance
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CENTEX HOMES May 9, 2003
TR 29734/Temecula Area J.N. 111-03
Page 9 •
of 20 feet is expected to be about one-half the total settlement. The anticipated
differential settlement of 3/8 inch in 20 feet may be expressed as an angular
distortion of 1:640. The anticipated differential settlement for fills greater than 10
' feet is 1/2 inch over 20 feet, an angular distortion of 1:480.
• Lots 1, 2, 30, 32, 33 and 36 through 43 -- The settlement characteristics of these
' lots which may be attributed to foundation loads and fill thickness are the same as
previously stated for fills 10 feet or less in thickness. However, because of the
presence of underlying clay shear zones in the bedrock, the potential for additional
' isolated differential movement should be considered. Accordingly,we recommend
that the potential for differential settlement be increased to 1 inch, applied over a
distance of 40 feet, an angular distortion of 1:480.
Lateral Resistance
A passive earth pressure of 250 psf per foot of depth may be used to determine lateral-
bearing resistance for building footings. A coefficient of friction of 0.35 times the
dead-load forces may also be used between concrete and the supporting soils to
determine lateral-sliding resistance. An increase of one-third of the above values may
also be used when designing for short-duration wind and seismic forces.
' The above values are based on footings placed directly against compacted fill or Pauba
Formation bedrock. In the case where footing sides are formed, backfill against the
' footings should be compacted to 90 percent or more of dry density.
Footing Observations
Footing trenches should be observed by a representative of Petra to document that they
' have been excavated into competent-bearing soils and to the embedments
recommended herein. 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 and any construction
debris should be removed prior to placing concrete.
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CENTEX HOMES May 9, 2003
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Excavated soils derived from footing and other excavations should not be placed in
' slab-on-ground areas.
' Expansive Soil Considerations
Results of laboratory tests by Petra indicate onsite soil and bedrock materials exhibit
VERY LOW expansion potential. It should be noted that additional slab thickness,
' footing sizes and/or reinforcement more stringent than the recommendations that
follow should be provided as recommended by the project architect or structural
' engineer.
' Conventional Slab-on-Ground Foundations (Lots 3 through 29, 31, 34 and 35)
The results of our laboratory tests indicate that onsite soils exhibit VERY LOW
' expansion potential (non-expansive) as classified in accordance with 1997 UBC Table
18-I-B. For this condition, it is recommended that footings and floors be constructed
' and reinforced in accordance with the following criteria. However, additional slab
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 for two-story
construction may be founded at a depth of 12 inches or greater below the lowest
adjacent final grade.
' - Continuous footings should be reinforced with two No. 4 bars, one top and one
bottom.
' - Isolated pad footings should be 24 inches or more square and founded at a depth
of 12 inches or more below the lowest adjacent final grade.
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• Floor Slabs
' - Living-area concrete-floor slabs should be 4 inches or more thick and reinforced
with either 6x6/W 1.4xW 1.4 welded-wire mesh or with No. 3 bars spaced 24
inches on-centers, both ways. Slab reinforcement should be properly supported
so that the desired placement is near mid-depth.
' - Living-area concrete floors should be underlain with a vapor retarder consisting
of 6-millimeter thick polyethylene membrane or equivalent. Two inches or
more of clean sand should 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
provided across garage entrances. The grade beam should be reinforced with
two No. 4 bars, one top and one bottom.
' - Prior to placing concrete, subgrade soils should be thoroughly moistened to
promote uniform curing of the concrete and reduce the development of
' shrinkage cracks.
tPost-Tensioned Slabs (Lots 1, 2, 30, 32, 33 and 36 through 43)
Post-tensioned slabs maybe designed in accordance with 1997 UBC Section 1819,
Design of Post-Tensioned Slabs on Compressible Soils. The design should
' accommodate non-expansive soil conditions and maximum differential settlement of
1 inch applied over 40 feet. Soil-bearing capacity and lateral resistance remain
applicable, as previously stated.
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CENTEX HOMES May 9, 2003
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Page 12
SEISMIC-DESIGN CONSIDERATIONS
Ground Motions
' Structures within the site should be designed and constructed to resist the effects of
seismic ground motions as provided in 1997 UBC 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 1997 UBC, 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 183 California faults that were digitized by the California Division of
Mines and Geology 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 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 the computer generated data using UBCSEIS, the Elsinore-Julian (Type A)
' segment of the Elsinore fault zone, located approximately 10.6 kilometers from the
site, could generate severe site ground motions with an anticipated maximum moment
magnitude of 7.1 and anticipated slip rate of 5.0 mm/year. However, the closest
Type B fault which is the Elsinore-Temecula fault located approximately 200 feet
southwest of Tract 29734 would probably generate the most severe site ground
motions with an anticipated maximum moment magnitude of 6.8 and anticipated slip
rate of 5.0 mm/year. Based on our evaluation using UBCSEIS, the following 1997
' UBC seismic design coefficients are recommended for the proposed residential
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CENTEX HOMES May 9, 2003
TR 29734/Temecula Area J.N. 111-03
Page 13
structures. These criteria are based on the soil profile type as determined by existing
' subsurface geologic conditions, on the proximity of the Elsinore-Temecula fault and
on the maximum moment magnitude and slip rate.
1997 UBC TABLE FACTOR
Figure 16-2 Seismic Zone 4
16-I Seismic Zone Factor Z 0.4
16-U Seismic Source Type B
' 16-J Soil Profile Type So
16-S Near-Source Factor N, 1.3
' 16-T Near-Source Factor N, 1.6
16-Q Seismic Coefficient C, 0.44 N,=0.57
16-R Seismic Coefficient C„ 0.64 N„= 1.02
SOIL CHEMISTRY
Laboratory test results indicate onsite soils contain negligible soluble sulfate contents.
' As such, concrete in contact with soil may utilize Type I or II Portland cement. The
laboratory test data for chloride concentration, resistivity and pH indicate onsite soils
' may be mildly corrosive to buried steel in direct contact with onsite soils.
RETAINING WALLS
Footing Embedments
' The base of retaining-wall footings constructed on level ground may be founded at a
depth of 12 inches below the lowest adjacent final grade. Where retaining walls are
' constructed on or within 15 feet from the top of adjacent descending fill slope, the
footings should be deepened such that a horizontal setback of H/3 (one-third the slope
' height) is maintained between the outside bottom edges of the footings and the slope
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CENTEX HOMES May 9, 2003
TR 29734/Temecula Area J.N. 111-03
' Page 14
' face; however, the footing setback should be 5 feet or more. The above-recommended
footing setbacks are preliminary and may require revision based on site-specific soil
' and/or bedrock conditions. Footing excavations should be observed by the project
geotechnical consultant to document that they 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 and At-Rest Earth Pressures
An active lateral-earth pressure equivalent to a fluid having a density of 40 pounds per
cubic foot (pcf) be used for design of cantilevered walls retaining a drained, level
' backfill. Where the wall backfill slopes upward at 2:1 (h:v), the above value should
be increased to 63 pcf. Retaining walls should be designed to resist surcharge loads
' imposed by other nearby walls or structures in addition to the above active earth
pressures.
' Drainage
' A perforated pipe-and-gravel subdrain should be installed behind retaining walls to
reduce the entrapment of water in the backfill. Perforated pipe should consist of 4-inch
' diameter or larger 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- to I.5-inch open-
graded gravel wrapped in filter fabric. Filter fabric may consist of Mirafi 140N or
' equivalent.
In lieu of a pipe-and-gravel subdrain, weepholes or open vertical masonry joints may
be considered for retaining walls not exceeding a height of approximately 3 feet.
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 no more than 32-inch intervals. A continuous gravel fill, 12 inches by 12
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CENTEX HOMES May 9, 2003
TR 29734/Temecula Area J.N. 111-03
Page 15
' inches, should be placed behind the weepholes or open masonry joints. The gravel
should be wrapped in filter fabric to prevent migration of fines and subsequent
clogging of the gravel. 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 foot or more 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 1 foot of the backdrain should be covered with
compacted fill. A drainage pipe consisting of 4-inch diameter perforated pipe
' (described above) surrounded by 1 cubic foot per foot of gravel or crushed rock
wrapped in a filter fabric should be provided along the back 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 and the wall should be appropriately waterproofed. The outside
portions of retaining walls supporting backfill should be coated with an approved
' waterproofing compound to inhibit migration of moisture through the walls.
Temporary Excavations
To facilitate retaining-wall construction, temporary slopes may be cut back at a
gradient of 1:1 (h:v) or gentler 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 temporary
slopes may be recommended. The potential effects of various parameters, such as
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CENTEX HOMES May 9, 2003
TR 29734/Temecula Area J.N. 111-03
Page 16
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 6- to 8-inch loose lifts, watered or air-dried
' as necessary to achieve near-optimum moisture conditions and compacted in place to
a relative compaction of 90 percent or more.
I
MASONRY GARDEN WALLS
Construction on or Near the Tops of Descending Slopes
' Continuous footings for masonry garden walls proposed on or within 7 feet from the
top of descending slopes should be deepened such that a horizontal clearance of 5 feet
is maintained between the outside bottom edge of the footing and the slope face. The
footings should be reinforced with two No. 4 bars, one top and one bottom and in
accordance with the recommendations provided by structural engineer. Plans for top-
of-slope block walls proposing pier and grade-beam footings should be reviewed by
Petra prior to construction.
Construction on Level Ground
Where masonry garden walls are proposed on level ground and 5 feet or more from the
tops of descending slopes, the footings for these walls may be founded at depth of 12
' inches below the lowest adjacent final grade. These footings should also be reinforced
with two No. 4 bars, one top and one bottom.
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CENTEX HOMES May 9, 2003
TR 29734/Temecula Area J.N. 111-03
1 Page 17
Construction Joints
1 In order to mitigate the potential for unsightly cracking related to the effects of
1 differential settlement, positive separations (construction joints) should be provided
in the walls at horizontal intervals of approximately 25 feet and at each corner. The
1 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 of the walls.
CONCRETE FLATWORK
1 Thickness and Joint Spacing
To reduce the potential of unsightly cracking, concrete sidewalks and patio-type slabs
should be 4 inches or more thick and provided with construction or expansion joints
every 6 feet or less. Concrete driveway slabs should be 4 inches or more thick and
1 provided with construction or expansion joints every 6 feet or less.
Subgrade Preparation
1 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 percent
1 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
1 depth of 12 inches 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 soils
engineer should observe and verify the density and moisture content of the soils and
the depth of moisture penetration prior to placing concrete.
1
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CENTEX HOMES May 9, 2003
TR 29734/Temecula Area J.N. 111-03
Page 18
' PLANTERS
Area drains should be extended into planters that are located within 5 feet of building
' walls, foundations, retaining walls and masonry garden 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 reduce
overwatering and subsequent saturation of the adjacent foundation soils.
UTILITY TRENCHES
' Utility-trench backfill within street right-of-ways, utility easements, under sidewalks,
driveways and building-floor slabs, as well as within or in proximity to slopes should
' be compacted to a relative density of 90 percent or more. Where onsite soils are
utilized as backfill, mechanical compaction is recommended. Density testing, along
' with probing, should be performed by the project soils engineer or his representative,
to document proper compaction.
' For deep trenches with vertical walls, backfill should be placed in approximately 1- to
' 2-foot thick loose lifts and then mechanically compacted with a hydra-hammer,
pneumatic tampers or similar equipment. For deep trenches with sloped-walls,backfill
' materials should be placed in approximately 8- to 12-inch thick loose lifts and then
compacted by rolling with a sheepsfoot tamper or similar equipment.
As an alternative for shallow trenches where pipe may be damaged by mechanical
compaction equipment, such as under building-floor slabs, imported clean sand having
a sand equivalent value of 30 or greater may be utilized. Observation, probing and,
' testing of the bedding should be performed.
•
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CENTEX HOMES May 9, 2003
TR 29734/Temecula Area J.N. 111-03
' Page 19
To avoid point-loads and subsequent distress to clay, cement or plastic pipe, imported
' sand bedding should be placed 1 foot or more above pipe in areas where excavated
trench materials contain significant cobbles.
Where utility trenches are proposed parallel to building footings (interior and/or
' exterior trenches), the bottom of the trench should not be located within a 1:1 (h:v)
plane projected downward from the outside bottom edge of the adjacent footing.
' SLOPE LANDSCAPING AND MAINTENANCE
The engineered slopes within the subject tract are considered grossly and surficially
Istable and are expected to remain so under normal conditions provided the slopes are
landscaped and maintained thereafter in accordance with the following
recommendations.
' • Compacted-earth berms should be constructed along the tops of the engineered fill
slopes to prevent water from flowing directly onto the slope surfaces.
• The slopes should be landscaped as soon as practical when irrigation water is
available. The landscaping should consist of deep-rooted, drought-tolerant and
maintenance-free plant species. A landscape architect should be consulted to
determine the most suitable groundcover. If landscaping cannot be provided within
a reasonable period of time, jute matting (or equivalent) or a spray-on product
designed to seal slope surfaces should be considered as a temporary measure to
reduce surface erosion until such time permanent landscape plants have become
well-established.
' • Irrigation systems should be installed on the engineered slopes and a watering
program then implemented which maintains a uniform, near-optimum moisture
condition in the soils. Overwatering and subsequent saturation of the slope soils
should be avoided. On the other hand, allowing the soils to dry-out is also
detrimental to slope performance.
• Irrigation systems should be constructed at the surface only. Construction of
sprinkler lines in trenches is not recommended.
•
02 e)
CENTEX HOMES May 9, 2003
TR 29734/Temecula Area J.N. 111-03
' Page 20
• During construction of terrace drains, downdrains or earth berms, care should be
taken to avoid placement of loose soil on the slope surfaces.
• A permanent slope-maintenance program should be initiated for major slopes not
maintained by individual homeowners. Proper slope maintenance should include
the care of drainage and erosion-control provisions, rodent control and repair of
' leaking or damaged irrigation systems.
• Provided the above recommendations are followed with respect to slope drainage,
' maintenance and landscaping, the potential for deep saturation of slope soils is
considered very low.
• Property owners should be advised of the potential problems that can develop when
drainage on the building pads and adjacent slopes are altered. Drainage can be
altered due to the placement of fill and construction of garden walls, retaining
walls, walkways, patios, swimming pool, spas and planters.
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 pre-soaking of subgrade soils below living-area and garage floor slabs
to document adequate moisture content and penetration.
' • Retaining-Wall Construction
' - Observe footing trenches when first excavated to document adequate depth and
competent soil-bearing conditions.
- Observe and document proper installation of subdrainage systems prior to
placing wall backfill.
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CENTEX HOMES May 9, 2003
TR 29734/Temecula Area J.N. 111-03
' Page 21
Observe and test placement of wall backfill to document adequate compaction.
' • Masonry Garden Wall Construction
' - Observe footing trenches when first excavated to document adequate depth and
competent soil-bearing conditions.
• Exterior Concrete-Flatwork Construction
' - Observe and test subgrade soils below concrete-flatwork areas to document
adequate compaction and moisture content.
• Utility-Trench Backfill
- Observe and test placement of utility-trench backfill to document adequate
compaction.
• Re-Grading
1 - Observe and test placement of fill to be placed above or beyond the grades
shown on the approved grading plans.
1
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' CENTEX HOMES May 9, 2003
TR 29734/Temecula Area J.N. 111-03
' Page 22
This opportunity to be of service is sincerely appreciated. If you have any questions,
Iplease contact this office.
IRespectfully submitted,
I
PETRA GEOTEC
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Attachments: Table 1 - Lot-By-Lot Summary of As-Graded Soil Conditions
Tables II and III -Field Density Test Results
I References
Plates 1 and 2 - Geotechnical Maps with Density Test Locations
(in pocket)
IAppendix A - Laboratory Test Criteria/Laboratory Test Data
Distribution: (3) Centex Homes
IAttention: Ms. Kimberly Surek
(1) Centex Homes - Field Office
Attention: Mr. Jim Lott
I (2) County of Riverside Building & Safety
Attention: Mr. Mack Hakakian
I
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1
1
1
1
1 TABLE
1
1 LOT-BY-LOT SUMMARY OF
1 AS-GRADED SOIL CONDITIONS
1
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1 PETRA
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a a a a a a OM M 0 0 MI MI a a a a a
TABLE I Tract 29734
LOT-BY-LOT SUMMARY OF SOIL CONDITIONS
Lot Maximum Fill Minimum Fill Estimated Soil Expansion Post-Tensioned Soil Condition Remarks
Number Depth(ft) Thickness(ft) Differential Index/Potential Slab Codes*
Settlement
1 5 5 1:480 8/V Low Yes P Pad underlain by steeply dipping clay shear zone
2 5 5 1:480 8/V Low Yes P Pad underlain by steeply dipping clay shear zone
3 12 10 1:480 8/V Low No Z
•
4 18 15 1:480 8/V Low No Z
5 21 15 1:480 8/V Low No Z
6 23 15 1:480 7/V Low No Z
7 30 15 1:480 7/V Low No Z
8 40 15 1:480 7/V Low No Z
9 15 15 1:480 7/V Low No Z
IO 10 9 1:640 1/V Low No Z
II 15 8 1:480 1/V Low No Z
12 12 8 1:480 I/V Low No Z
13 13 5 1:480 l/V Low No Z
14 10 10 1:640 2/V Low No Z
15 10 10 1:640 2/V Low No Z
16 6 5 1:640 2/V Low No Z
17 3 3 1:640 2/V Low No Z
18 0 0 1:640 8/V Low No Z
*per County of Riverside,Building and Safety Department Plan Check Memorandum dated April 5,2001
Code Definitions(Reference: 1997 UBC):
E Foundations for structures resting on soils with an expansion index greater than 20(Section 1803.2)
C For corrosion protection, if Table I 9-A-2 is applicable
S If exposure of concrete to sulfate-containing solutions is moderate or higher per Table 19-A-4
D Differential deflection in the foundation due to differential settlement exceeds value in Table 18-III-GG(consider Prefab Roof Trusses)[noted if>1:480]
P If post-tensioned slab system is to be used
U Z If none of the above is applicable Table T-I 1
= a a In a a a a OM M a a 0 0 — =I MI
TABLE I Tract 29734
LOT-BY-LOT SUMMARY OF SOIL CONDITIONS
Lot Maximum Fill Minimum Fill Estimated Soil Expansion Post-Tensioned Soil Condition Remarks
Number Depth(ft) Thickness(ft) Differential Index/Potential Slab Codes*
Settlement
19 3 3 1:640 8/V Low No Z
20 3 3 1:640 8/V Low No Z
21 7 7 1:640 8/V Low No Z
22 6 6 1:640 6/V Low No Z
23 5 5 1:640 6/V Low No Z
24 3 3 1:640 6/V Low No 1
25 4 4 1:640 4/V Low No Z
26 4 4 1:640 4/V Low No Z
27 4 4 1:640 4/V Low No Z
S628 15 15 1:480 4/V Low No Z
N4 29 9 9 1:640 I/V Low No Z
`` � 30 6 6 1:480 1/V Low Yes P Pad underlain by steeply dipping clay shear zone
V
v31 7 7 1:640 1/V Low No Z
32 5 5 1:480 I/V Low Yes P Pad underlain by steeply dipping clay shear zone
33 4 4 I:480 3/V Low Yes P Pad underlain by steeply dipping clay shear zone
34 4 4 1:640 3/V Low No Z
35 5 5 1:640 3/V Low No Z
36 6 6 1:480 7/V Low Yes P Pad underlain by steeply dipping clay shear zone
*per County of Riverside,Building and Safety Department Plan Check Memorandum dated April 5,2001
Code Definitions(Reference: 1997 UBC):
E Foundations for structures resting on soils with an expansion index greater than 20(Section 1803.2)
C For corrosion protection,if Table 19-A-2 is applicable
S If exposure of concrete to sulfate-containing solutions is moderate or higher per Table 19-A-4
D Differential deflection in the foundation due to differential settlement exceeds value in Table 18-III-GG(consider Prefab Roof Trusses)[noted if>1:480]
P If post-tensioned slab system is to be used
ita
6- Z If none of the above is applicable Table T-I 2
M IMI - a a - MEM - a M M 5 a
TABLE I Tract 29734
LOT-BY-LOT SUMMARY OF SOIL CONDITIONS
Lot Maximum Fill Minimum Fill Estimated Soil Expansion Post-Tensioned Soil Condition Remarks
Number Depth(ft) Thickness(ft) Differential Index/Potential Slab Codes*
Settlement
37 5 5 1:646 00 7/V Low Yes P Pad underlain by steeply dipping clay shear zone
38 5 5 1:646 7/V Low Yes P Pad underlain by steeply dipping clay shear zone
39 6 6 l:640 5/V Low Yes P Pad underlain by steeply dipping clay shear zone
40 5 5 1:640 5/V Low Yes P Pad underlain by steeply dipping clay shear zone
41 6 6 1:640 5/V Low Yes P Pad underlain by steeply dipping clay shear zone
42 6 6 I:12r0 5/V Low Yes P Pad underlain by steeply dipping clay shear zone
43 4 4 1:640 1✓ 5/V Low Yes P Pad underlain by steeply dipping clay shear zone
*per County of Riverside,Building and Safety Department Plan Check Memorandum dated April 5,2001
Code Definitions(Reference: 1997 UBC):
E Foundations for structures resting on soils with an expansion index greater than 20(Section 1803.2)
C For corrosion protection, if Table 19-A-2 is applicable
S If exposure of concrete to sulfate-containing solutions is moderate or higher per Table I 9-A-4
D Differential deflection in the foundation due to differential settlement exceeds value in Table I8-III-GG(consider Prefab Roof Trusses)[noted if>1:4867
P If post-tensioned slab system is to be used
Z If none of the above is applicable Table T-I 3
1
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1 TABLE II
1
1 FIELD DENSITY TEST RESULTS
1 (MASS GRADING)
i
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1 t PETRA
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as
ITABLE II - Phase I (Mass Grading)
IField Density Test Results
Test Test No. Test Location Elev. Moisture Dry Dens RC Max Dens
I
11040 (it) POE En i 0 m
6ify i imi 90A (Pei
I01/24/02 1321 Lot 8 1163.0 11.3 119.7 93 129.0
01/24/02 1322 Lot 5 1167.0 11.1 118.3 92 129.0
01/24/02 1323 Lot 9 1162.0 10.5 120.5 92 130.5
1 01/29/02 1324 Lot 5 1174.0 10.9 117.5 91 129.0
II 01/29/02 1325 Lot 8 slope 1165.0 10.7 117.5 91 129.0
01/29/02 1326 Lot 8 slope 1166.0 9.9 118.3 92 129.0
I01/29/02 1327 Lot 7 1169.0 10.3 117.7 91 129.0
01/29/02 1328 Lot 6 1174.0 9.9 119.1 91 131.5
01/29/02 1329 Lot 4 slope 1176.0 10.1 119.7 91 131.5
01/29/02 1330 Lot 6 1176.0 8.7 118.5 90 131.5
01/29/02 1331 Lot 9 slope 1167.0 11.3 117.1 91 129.0
' 01/29/02 1332 Lot 8* 1168.0 10.9 118.9 90 131.5
01/29/02 1333 Lot 4 slope 1182.0 10.7 117.9 91 129.0
01/29/02 1334 Lots 1178.0 11.1 118.1 92 129.0
• 01/29/02 1335 Lots slope 1174.0 10.7 119.0 90 131.5
01/29/02 1336 Lot? 1170.0 11.0 119.5 91 131.5
01/29/02 1337 Lot 8 slope 1169.0 10.1 122.1 92 133.0
I01/29/02 1338 Lot 9 slope 1166.0 10.7 118.3 92 129.0
01/30/02 1339 Lot 4 slope 1181.0 10.1 119.1 91 130.5
01/30/02 1340 Lot 5 slope 1183.0 10.7 118.3 92 129.0
I01/30/02 1341 Lot 6 slope 1177.0 9.9 117.9 91 129.0
01/30/02 1342 Lot 7 1172.0 10.7 118.9 91 130.5
01/30/02 1343 Lot 8 slope 1169.0 10.1 117.3 91 129.0
01/30/02 1344 Lot 9 slope 1168.0 10.9 118.1 92 129.0
01/30/02 1345 Lot 3 1184.0 11.0 116.9 91 129.0
01/30/02 1346 Lot 6* 1177.0 10.0 118.9 90 131.5
I
01/30/02 1347 Lot 6 slope 1173.0 9.3 118.5 90 131.5
01/30/02 1348 Lot 8 1172.0 10.1 116.1 90 129.0
I01/30/02 1349 Lot 3 slope 1186.0 10.7 116.5 90 129.0
01/30/02 1350 Lot 5 slope 1180.0 10.7 118.1 90 130.5
01/30/02 1351 Lot6 1179.0 10.1 118.7 91 130.5
I01/30/02 1352 Lot 7 1174.0 10.9 117.7 90 130.5
01/30/02 1353 Lot 8 slope 1169.0 11.1 116.3 90 129.0
01/30/02 1354 Lot 8 1170.0 11.3 116.9 91 129.0
I01/30/02 1355 Lot 9* 1170.0 10.9 117.5 90 130.5
01/30/02 1356 Lot 8 1171.0 10.7 117.0 91 129.0
01/30/02 1357 Lot 8 1173.0 10.0 116.7 90 129.0
01/30/02 1358 Lot 7 slope 1174.0 9.7 121.9 92 133.0
01/31/02 1359 Lot 9 1173.0 9.9 118.7 91 131.0
I01/31/02 1360 Lot 8 1176.0 9.7 118.3 90 131.0
01/31/02 1361 Lot 7 slope 1176.0 8.9 117.9 90 131.0
01/31/02 1362 Lot6 1180.0 9.1 118.9 91 131.0
I PETRA GEOTECHNICAL, INC. TR 29734 OCTOBER 2002
J.N. 436-01 * Sandcone TABLE T-II 1
TABLE II - Phase I (Mass Grading)
IField Density Test Results
Test `Test No. 'fest Location Etev ot
Misut e Dry DeusRCMax Dens
Date ([t) (%) (Atf)' (°/q). tPG
01/31/02 1363 Lot 8 1175.0 10.7 117.3 91 129.0
I
01/31/02 1364 Lot 9 1174.0 11.0 116.9 91 129.0
01/31/02 1365 Lot7 1177.0 11.1 116.3 90 129.0
' 01/31/02 1366 Lot 5 1183.0 11.5 119.1 91 130.5
01/31/02 1367 Lot 6 slope 1182.0 10.7 118.3 91 130.5
01/31/02 1368 Lot 8 1178.0 10.9 118.1 90 130.5
I01/31/02 1369 Lot 9 1177.0 11.3 113.7 91 125.5
02/01/02 1370 Lot 7 1182.0 10.1 118.3 90 131.0
02/01/02 1371 Lot? 1184.0 9.7 117.9 90 131.0
Il02/01/02 1372 Lot 3 1188.0 9.9 119.1 91 131.0
02/01/02 1373 Lot 5 slope 1185.0 8.9 118.3 90 131.0
a 02/01/02 1374 Lot 6 1185.0 9.3 119.0 91 131.0
02/22/02 1450 Lot5 1189.0 10.7 117.9 91 129.0
02/22/02 1451 Lot 8 1181.0 11.1 118.3 92 129.0
I02/22/02 1452 Lot? 1182.0 11.5 117.7 91 129.0
02/22/02 1453 Lot 8 1183.0 10.1 118.9 91 131.0
02/22/02 1454 Lot 6 1188.0 9.7 119.5 91 131.0
I02/22/02 1455 Lot8 1185.0 12.7 114.7 91 125.5
02/22/02 1456 Lot 9 1186.0 13.3 113.9 91 125.5
02/22/02 1457 Lot 7 1187.0 9.9 119.0 91 131.0
I02/22/02 1458 Lot 8 1188.0 11.0 118.0 91 129.0
02/22/02 1459 Lot 9 1189.0 10.3 118.1 92 129.0
02/22/02 1460 Lot5 1191.0 9.7 119.5 91 131.0
I02/22/02 1461 Lot 4 1196.0 9.9 119.1 91 131.0
02/25/02 1462 Lot 6* 1190.0 10.7 117.7 91 129.0
02/25/02 1463 Lot 4 1197.0 10.3 118.3 92 129.0
I02/25/02 1464 Lot 6 1193.0 11.5 118.0 91 129.0
02/25/02 1465 Lot5 1193.0 9.1 120.0 92 131.0
I02/25/02 1466 Lot 13* 1203.0 10.5 119.9 92 131.0
02/25/02 1467 Lot 12 1195.0 9.9 119.7 91 131.0
02/25/02 1468 Lot 11 1193.0 10.7 117.7 91 129.0
I02/25/02 1469 Lot 15 1210.0 10.1 118.3 92 129.0
02/25/02 1470 Lot 14 1203.0 9.9 117.5 91 129.0
02/25/02 1471 Lot 14 1206.0 11.3 116.9 91 129.0
I02/25/02 1472 Lot 13 1205.0 11.0 121.0 92 131.0
02/25/02 1473 Lot 10 1189.0 9.9 120.7 92 131.0
02/25/02 1474 Lot 9 1185.0 10.7 119.1 92 129.0
I02/27/02 1501 Lot 9 1189.0 12.2 119.5 90 132.5
02/27/02 1502 Lot 14 1208.0 9.3 119.2 90 132.5
02/27/02 1503 Lot 13* 1206.0 9.2 119.4 90 132.5
I02/27/02 1504 Lot 12* 1197.7 12.7 117.9 89 132.5
02/27/02 1505 Lot 11* 1195.0 13.2 119.1 90 132.5
I PETRA GEOTECHNICAL, INC. TR 29734 OCTOBER 2002
J.N. 436-01 * Sandcone TABLE T-II 2
.10
ITABLE II - Phase I (Mass Grading)
IField Density Test Results
Tess Test No, Fest Location Eley. Maisture Dry Dens RC Max Dens
IAate (ft) ' (°!°) 01;0 (°la) flit.
02/27/02 1506 Lot 10 1190.0 11,6 124.5 95 130.5
' 02/27/02 1507 Lot 9 1192.0 12.7 120.5 92 130.5
02/27/02 1508 RT No. 1504 -- 11.2 117.5 90 130.5
02/27/02 1509 Lot 15 1212.0 9.8 118.9 91 130.5
I 02/27/02 1510 Lot 10 1194.0 11.3 121.4 93 130.5
02/27/02 1511 Lot 11 1197.0 12.0 122.7 94 130.5
I 02/27/02 1512 Lot 14 1209.0 11.0 120.4 92 130.5
• 02/27/02 1513 Lot 15 1213.0 9.0 127.4 96 132.5
02/27/02 1514 Lot 12 1201.0 8.7 124.1 94 132.5
' 02/27/02 1515 Lot 9 1194.0 9.5 122.2 92 132.5
02/27/02 1516 Lot 11 1198.0 9.3 122.0 92 132.5
02/27/02 1517 Lot ? 1189.0 11.2 120.6 91 132.5
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02/27/02 1518 Lot 6 1191.0 11.0 123.2 93 132.5
02/27/02 1519 Lot 4 1198.0 10.6 121.7 92 132.5
02/28/02 1520 Lot 6 1194.0 10.9 119.3 90 132.5
I02/28/02 1521 Lot 8 1191.0 10.1 120.4 91 132.5
02/28/02 1522 Lot 7 1191.0 10.5 123.4 93 132.5
I02/28/02 1523 Lot 9 1192.0 9.5 121.6 92 132.5
02/28/02 1524 Lot 6 1194.0 9.3 120.6 91 132.5
02/27/02 1525 Lot 10 1185.0 12.0 122.5 92 132.5
I03/08/02 1616 Lot 3* 1196.0 7.6 119.0 89 133.0
03/08/02 1617 RT No. 1616 8.7 119.8 90 133.0
03/08/02 1618 Lot 3 1200.0 9.3 116.2 88 131.5
I03/08/02 1619 RT No. 1618 -- 9.4 118.8 90 131.5
03/08/02 1620 Lot 16 1213.0 7.5 120.3 91 131.5
03/08/02 1621 Lot 16 1214.0 7.6 122.8 93 131.5
I03/08/02 1623 Lot 16 1215.0 8.8 117.7 90 131.5
03/08/02 1624 Lot 26* 1200.0 9.6 116.9 89 131.5
I03/11/02 1625 RTNo. 1624 -- 10.7 118.6 90 131.5
03/11/02 1627 Lot26 1203.0 9.7 121.1 92 131.5
03/11/02 1628 Lot26 1204.0 11.8 118.5 90 131.5
a 03/11/02 1629 Lot 16 1214.0 9.8 117.4 90 131.0
03/11/02 1630 Lot 16 1215.0 9.9 118.4 91 130.5
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J.N. 436-01 * Sandcone TABLE T-II 3
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TABLE III
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I FIELD DENSITY TEST RESULTS
I (ROUGH GRADING)
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ITABLE III - Phase II (Rough Grading)
IField Density Test Results
' Test Test Na. Test Location Eteu Moisture Dry Dens RC Max Dens
Date (ftl (°Jo) (peO ("te) (Iter
07/11/02 1 Lot 16 1214.0 8.1 117.5 90 130.5
07/11/02 2 Lot 25 1197.0 4.9 113.8 87 130.5
' 07/11/02 3 Lot 20 slope 1216.0 5.4 112.4 86 130.5
07/11/02 4 RTNo. 2 7.9 117.6 90 130.5
07/11/02 5 Lot23 1205.0 6.9 119.1 90 132.0
I07/11/02 6 Lot 21 1210.0 7.1 120.3 91 132.0
07/11/02 7 RTNo. 3 8.4 118.9 90 132.0
07/12/02 8 Lot 22 slope 1215.0 9.6 117.6 90 130.5
07/12/02 9 Lot 25 slope 1202.0 9.4 118.9 91 130.5
07/12/02 10 Lot 22* 1210.0 8.7 120.3 92 130.5
' 07/12/02 11 Lot 20 1215.0 10.1 117.9 91 129.5
07/15/02 12 Lot 27 1207.0 9.1 120.6 93 129.5
07/15/02 13 Lot 28 1211.0 8.9 121.6 93 130.5
• 07/15/02 14 Lot 29 1217.0 9.4 117.9 91 129.5
111 07/15/02 ' 15 Lot 28 1214.0 10.1 121.9 94 129.5
07/15/02 16 Lot 29 1219.0 9.8 114.6 90 127.0
I 07/15/02 17 Lot 20 slope 1220.0 10.7 118.2 91 129.5
07/16/02 18 Lot 30 1224.0 9.6 118.0 91 129.5
07/16/02 19 Lot 31 1227.0 9.2 121.5 93 130.5
I07/16/02 20 Lot 22 slope* 1219.0 9.4 121.6 92 132.0
07/16/02 21 Lot 20 slope 1226.0 9.1 124.3 94 132.0
07/17/02 22 Lot 43 1198.0 5.6 117.7 90 130.5
' 07/17/02 23 Lot 41 1209.0 5.8 112.6 86 130.5
07/17/02 24 Lot 39 1222.0 6.1 116.3 88 132.0
• 07/18/02 25 RTNo. 22 -- 9.6 119.4 91 130.5
Ill 07/18/02 26 RT No. 23 9.8 119.9 92 130.5
07/18/02 27 RT No. 24 -- 9.1 123.0 93 132.0
0 07/18/02 28 Lot 35 1227.0 9.5 123.3 93 132.0
111 07/18/02 29 Lot 34 1228.0 9.8 123.1 93 132.0
07/18/02 30 Lot40 1218.0 8.9 116.8 90 130.5
' 07/18/02 31 Lot 38 1228.0 9.7 120.4 92 130.5
07/18/02 32 Lot 32 1229.0 8.7 122.9 93 132.0
07/22/02 33 Lot 33 1226.0 10.1 120.3 92 130.5
I07/22/02 34 Lot 34 1226.0 9.3 120.4 91 132.0
03/27/03 35 Lot 9 1190.0 10.5 119.9 91 132.0
03/27/03 36 Lot 9 1191.0 11.2 118.7 90 132.0
03/27/03 37 Lot 9 1194.0 11.4 119.9 91 132.0
03/28/03 38 Lot 1 1196.0 10.1 120.9 92 132.0
03/28/03 39 Lot 1 1199.0 9.5 121.3 92 132.0
I 03/31/03 40 Lot 1 1198.0 9.5 120.5 91 132.0
I PETRA GEOTECHNICAL, INC. TR 29734 MAY 2003
J.N. 111-03 * Sandcone TABLE III-1
TABLE III - Phase II (Rough Grading)
IField Density Test Results
iMaTiSf].:RNIeSt!INCEgUi!;.: !Mii3e.StLocation Eley. Moisture Dry Dens RG Max Dens
' hate {ft) (°1a) (pt5 {%) (Pcf3
03/31/03 41 2 1200.0 8.8 120.9 92 132.0
I04/01/03 42 Lot37 1219.0 8.5 121.7 93 130.5
04/01/03 43 Lot 37 1221.0 9.1 119.8 92 130.5
I04/01/03 44 Lot 41 1222.0 8.8 120.9 93 130.5
04/01/03 45 Lot 41 1212.0 8.0 121.4 93 130.5
04/02/03 46 Lot 39 1221.0 9.1 120.1 91 132.0
I04/02/03 47 Lot 41 1213.0 10.2 119.5 91 132.0
04/02/03 48 Lot 40 1212.0 9.4 119.9 91 132.0
04/04/03 49 Lot 38 1224.0 9.3 120.8 92 132.0
' 04/04/03 50 Lot 39 1222.0 9.0 122.2 93 132.0
04/04/03 51 Lot 40 1213.0 8.8 121.7 92 132.0
04/07/03 52 Lot 38 1225.0 9.0 119.8 91 132.0
'
04/07/03 53 Lot 39 1223.0 9.4 120.1 91 132.0
04/08/03 54 Lot 40 1215.0 8.1 121.3 92 132.0
' 04/08/03 55 Lot 40 1217.0 8.5 120.7 91 132.0
04/08/03 56 Lot 39 1224.0 9.2 119.5 91 132.0
04/08/03 57 Lot 39 1226.0 8.3 121.2 92 132.0
I 04/08/03 58 Lot 38 1226.0 8.7 119.6 91 132.0
04/08/03 59 Lot 38 1228.0 8.1 121.1 92 132.0
04/10/03 60 Lot 38 1229.0 9.2 119.8 91 132.0
I04/10/03 61 Lot 38 1230.0 8.8 120.7 91 132.0
04/10/03 62 Lot 36 1223.0 8.5 120.4 91 132.0
04/10/03 63 Lot 9 slope 1184.0 8.1 119.5 91 132.0
' 04/11/03 64 Lot 36 1224.0 8.4 119.9 91 132.0
04/11/03 65 Lot 36 1225.0 8.7 118.8 90 132.0
04/21/03 66 Lot 18 FG 8.6 118.8 90 132.0
I04/21/03 67 Lot 17 FG 8.4 120.2 91 132.0
04/21/03 68 Lot 16 FG 9.8 118.7 90 132.0
' 04/21/03 69 Lot 19 FG 9.1 122.5 93 132.0
04/21/03 70 Lot 20 FG 9.3 124.2 94 132.0
04/21/03 71 Lot 21 FG 12.9 117.8 90 130.5
I04/21/03 72 Lot 15 FG 7.8 125.1 95 132.0
04/21/03 73 Lot 14 FG 7.2 125.4 95 132.0
04/21/03 74 Lot 13 FG 7.5 123.2 93 132.0
I04/21/03 75 Lot 12 FG 9.2 122.5 93 132.0
04/21/03 76 Lot 11 FG 10.1 117.7 90 130.5
04/21/03 77 Lot 25 FG 11.0 118.6 91 130.5
I04/21/03 78 Lot 24 FG 11.1 117.8 90 130.5
04/21/03 79 Lot 23 FG 3.2 120.7 91 132.0
04/21/03 80 Lot 22 FG 10.1 119.9 91 132.0
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04/25/03 81 Lot 2 FG 8.3 121.3 92 132.0
PETRA GEOTECHNICAL, INC. TR 29734 MAY 2003
J.N. 111-03 * Sandcone TABLE III-2
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TABLE Ill - Phase II (Rough Grading)
IField Density Test Results
'Test Test No. 'Test Location E1ev. Moisture Dry Dens RC lVM.aix Dens
' .pate (ttt) (%) (Pet}:: {"kuj (pet„
' 04/25/03 82 Lot 3 FG 8.5 121.0 92 132.0
04/25/03 83 Lot 4 FG 8.0 119.8 91 132.0
04/25/03 84 Lot 5 FG 12.1 114.8 91 126.0
t04/25/03 85 Lot 6 FG 11.2 115.4 92 126.0
04/25/03 86 Lot 7 FG 11.5 116.8 93 126.0
04/25/03 87 Lot 8 FG 8.0 120.9 92 132.0
I04/25/03 88 Lot 9 FG 9.5 119.7 91 132.0
04/25/03 89 Lot 10 FG 9.3 119.4 90 132.0
04/25/03 90 Lot 43 FG 10.2 120.2 90 133.0
' 04/25/03 91 Lot 42 FG 10.6 120.0 90 133.0
04/25/03 92 Lot 26 FG 9.7 122.4 92 133.0
04/25/03 93 Lot 27 FG 9.0 119.9 91 132.0
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04/25/03 94 Lot 28 FG 8.4 121.3 92 132.0
04/25/03 95 Lot 29 FG 8.1 121.9 92 132.0
I04/26/03 96 Lot 35 FG 8.7 119.6 91 132.0
04/26/03 97 Lot 34 FG 8.2 119.9 91 132.0
04/26/03 98 Lot 33 FG 9.3 120.7 91 133.0
' 04/26/03 99 Lot 32 FG 9.0 120.9 91 133.0
04/26/03 100 Lot 31 FG 8.8 121.7 92 133.0
04/26/03 101 Lot 30 FG 8.3 120.4 91 132.0
I04/26/03 102 Lot 39 FG 8.9 119.6 91 132.0
04/26/03 103 Lot 40 FG 9.2 120.3 90 133.0
04/26/03 104 Lot 31 finish slope FG 8.3 121.1 92 132.0
I04/26/03 105 Lot 27 finish slope FG 8.0 119.9 91 132.0
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J.N. 111-03 * Sandcone TABLE III-3
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REFERENCES
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REFERENCES
' Blake,T.F., 1998/1999,"UBCSEIS"Version 1.03,A Computer Program for the Estimation of Uniform Building Code
1 Coefficients Using 3-D Fault Sources.
International Conference of Building Officials, 1997, "Uniform Building Code," Volume 2, Structural Engineering
Design Provisions, dated April 1997.
Earth Research Associates, Inc., 1987, Evaluation of Faulting and Liquefaction Potential, Portion of Wolf Valley
Project, Rancho California, County of Riverside, California, J.N. 298-87,dated November 20.
' , 1988, Preliminary Soils Engineering and Engineering Geologic Investigation, Red Hawk Project, Rancho
California Area, County of Riverside,California, J.N. 298-87, dated February 2.
' Petra Geotechnical, Inc., 1989, Supplemental Soils Engineering and Engineering Geologic Investigation, Portion of
Redhawk Project, Vesting Tentative Tract Map Nos. 23064, 23065, 23066 and 23067, Rancho California,
County of Riverside, California, Volumes I and II;for Great American Development, J.N. 298-87, dated
t May 8.
, 2001a,Updated Preliminary Geotechnical Investigation,Tract 23065 Phases 3 though 7 and Final,Redhawk
Development,Temecula Area,Riverside County,California;for The Garrett Group LLC, J.N. 165-01,dated
April 11.
,2001b,Response to Riverside County Building and Safety Department Geotechnical Report Review Sheet,
' Dated July 7,2001, and Grading-Plan Review Report for Tract 23065-F,Temecula Area, Riverside County,
California;for The Garrett Group LLC,J.N. 165-01, dated August 30.
' ,2001c,Response to Riverside County Building and Safety Department Geotechnical Report Review Sheet,
Dated November 5,2001,Tract 23065-F,Temecula Area,Riverside County,California;for The Garrett Group
LLC, J.N. 165-01, dated November 21.
' , 2001d,Response to Riverside County Building and Safety Department Geotechnical Report Review Sheet
Dated November 21, 2001, Tract 23065-F, Temecula Area, Riverside County, California;for The Garrett
Group, LLC,J.N. 165-01, dated December 13.
' , 2002a, Geotechnical Report of Mass Grading,Tract 29734,Temecula Area, Riverside County, California,
J.N. 436-01, dated June 26.
t , 2002b, Preliminary Foundation Recommendations, Lots 1 through 43, Tract 29734, Temecula Area of
Riverside County, California,J.N.401-01, dated August 2.
PETRA GEOTECHNICAL, INC. MAY 2003
' J.N. 111-03
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1 APPENDIX A
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1 LABORATORY TEST CRITERIA
1 LABORATORY TEST DATA
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' APPENDIX A
' LABORATORY TEST CRITERIA
Laboratory Maximum Dry Density
IMaximum dry density and optimum moisture content were determined for selected samples of soil and bedrock materials
in accordance with ASTM Test Method DI557. Pertinent test values are given on Plates A-1 and A-2.
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Expansion Potential
' Expansion index tests were performed on selected samples of soil and bedrock materials in accordance with ASTM Test
Method D4829. Expansion potential classifications were determined from 1997 UBC Table 18-I-B on the basis of the
expansion index values. Test results and expansion potentials are presented on Plate A-3.
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Soil Chemistry
' Chemical analyses were performed on selected samples of onsite soil to determine concentrations of soluble sulfate and
chloride,as well as pH and resistivity. These tests were performed in accordance with California Test Method Nos.417
' (sulfate),422 (chloride)and 643 (pH and resistivity). Test results are presented on Plate A-3.
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' PETRA GEOTECHNICAL, INC. MAY 2003
' J.N. 111-03
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' LABORATORY MAXIMUM DRY DENSITY'
I i Sf os' iww r Sv _ i : �a ' l aanax mm
l�kX*!ifiLt rt,I & te t' r ' ,tf- 2 sr7E 4:441 SN,. iettf. `
t.' ample N ( ft r l,yt o �Type'f +:Moisu • DryuQenstty
tir 9Y !eStili. VI ''ad 3tmfrM42-1Py i'$, %tlik fg t
' 1 Yellow brown Silty SAND with Gravel 9.5 130.5
3 Olive brown Silty SAND, micaceous 8.5 132.5
I4 Reddish brown Silty SAND 8.0 131.0
5 Light brown Silty SAND 8.5 133.0
' 6 Medium brown Silty SAND 8.5 131.5
7 Yellow brown Silty SAND 10.5 125.5
I9 Reddish brown Clayey SAND 9.5 129.0
10 Light yellow brown Silty SAND 8.5 131.0
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12 Brown Silty SAND 9.0 130.5
15 Light brown Silty SAND 8.5 132.0
I18 Olive brown Clayey Silty SAND 9.5 130.5
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19 Light yellow brown SAND with trace Gravel and fines 9.5 129.5
21
Light brown Silty Clayey SAND 11.0 127.0
I32 Brown Silty SAND 8.0 132.0
(I)PER ASTM TEST METHOD D1557
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IJ.N. 111-03 Plate A-1
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' EXPANSION INDEX TEST DATA
K�„sa r3 vT "� 'i. T 4t it ?r w n iyoit Gad * r+-saW.. amp ys r r r-opl �„'Lx*.� 3
a^ , r k : b*' m hxpansion q Expansion,t
"'gatI `t r Rm _ :ui'E tit -t' : x ,rte .Z'- mgr# t aPOtential c
_t�,r�vSamplellot,�*� ,� �,x� ��RepresentaU'vel`Lotst�t�"�'�`+„,,:�,�.tt�� h. ,Index+,:°_y�`�"_
' 1 1 through 5 8 Very Low
6 6 through 9 7 Very Low
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10 10 through 13 1 Very Low
14 14 through 17 2 Very Low
I 18 18 through 21 8 Very Low
22 22 through 24 6 Very Low
I25 25 through 28 4 Very Low
29 29 through 32 I Very Low
I33 33 through 35 3 Very Low
36 36 through 38 7 Very Low
I39 39 through 43 5 Very Low
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SOLUBLE CHEMISTRY
t o ids° Ii r I qt*u �} litt ' rp.s lckr. m`� i c k �1 Gt r '�ca Cs,Ls�t ,g
(. r- LOt NO e ,w4. .Sn)fatec. t.CI1lOp ck cN zpH ,T "- RQSIStivtt)'yr en +('Orrosivitypp"A
I e .-,. 47 a"a e ,.k orrnal, t r+.,4.r4r+ :.t a4-iti Pm"s.Pier e tt...,4- R r i t i A e
k �..rl'w t;aa2 igen .,.. (SYMCF! :Mel tkz(ppm)'.-t _r lt41111a7Z (Ohrn-emit „,, ,.,,KPOtential' Myo 1
6 0.069 105 7.41 5,700 concrete: negligible
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steel: mild
18 0.075 136 7.45 8,800 concrete: negligible
steel: mild
I 39 0.066 129 7.4 10,400 concrete: negligible
steel: moderate
I (2)PER ASTM TEST METHOD D4829
(4)PER CALIFORNIA TEST METHOD NO.417
(5)PER CALIFORNIA TEST METHOD NO.422
(6)PER CALIFORNIA TEST METHOD NO. 643
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(7)PER CALIFORNIA TEST METHOD NO. 643
(8)PER ASTM TEST METHOD D4318
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' PETRA GEOTECHNICAL, INC. MAY 2003
IJ.N. 111-03 Plate A-2
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