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PRELIAIINAM, GEOTECHNICAL EVALUATION
IM
PROPOSED RESIDENTIAL DEVELOPMENT
41923 SECOND STREET
TEMECULA, CALIFORNIA 92590
PRO.IEcr No. 3032SD3
PREPARED FOR
P, -',NCH DEVELOPAIEN.I.
39495 CALLS DE COMPANERO
IMURRIETA, CA 92562
PREPARED M
GEoTEK, INC.
1384 POINSETTIA AVENUE
VISTA, CALIFORNIA 92081-8505
h: O
EK. INC.
JUNE 5, 2006
L
1384 Poinsettia Ave., Suite A
Vista, CA 92081-8505
(760) 599-0509 FAX (760) 599-0593
K9 INC
Reach Development Tne.
39495 Calle de Companero
Murrieta, CA 92562
Subject Preliminary Geotechnical Evaluation
Proposed Residential Development
41923 Second Street
Temecula, CA 92590
Dear Mr. Truax:
0
Geotechnical
Environmental
Materials
June 5, 2006
Project No. 3632SD3
As requested and authorized, GeoTek, Inc. (GeoTelc) has performed a geotechnical
evaluation for the proposed site located northwest of the intersection of Second and
Mercedes Streets in the City of Temecula, California. This report presents the results of
our evaluation, discussion of our findings, and provides geotechnical recommendations
for foundation design and construction. In our opinion, the proposed development of the
site appears feasible from a geotechnical viewpoint provided that the recommendations
included herein are incorporated into the design and construction phases of the project.
The opportunity to be of service is sincerely appreciated. If you should have any questions,
please de not hesitate to call our office.
Respectfully
GeoTek,IInc.
Simon I. Saiid, �oFcu
RdE 264-1, Exp. 9130107
Project Manager
(4) Addressee
G Projec WyOjwk 3000 m 39991Pr0Jees 3000 to 3049130315036'. HKml Raach Av tio.doc
QF GA11�
Jei'freyP. Blake,
CEG 2248, Exp. 10/31/07
Senior Engineering Geologist
ARIZONA CALIFORNIA IDAHO
NEVADA
0 0
Ranch De\elopment Inc. Pr6ecl 3031SD3
Preliminan, Geotechnical Evaluation \qac 17. 1006
Proposed Residential Devclopntent Pa_e I
TABLE OF CONTENTS
1. I N' F I: N'1'.....................................................................................................................................
2. PURPOSE AND SCOPE OF SERVICES ..............................................................................
3. SITE DESCRIPTION AND PROPOSED DEVELOP -MEN -1 ..........................................................................2
3.1 SFFEDESCRIP'I'ION...... ..... .... ............. ..... ............. .......
.......... ... ...... ..... _2
3_' PROPOSEDDL\FLOP.\IENF...........................................................................
.- .. . .. ....... ._2
a. FIELD ESPLORA'I'ION AND LABORA'T'ORY TESTING ............................................................................2
4.1 Il ELI) EAPLORA IKON ................. ............ ... .... .... ......... -- ..... .... .... .-.. .....
.. ........................
4.2 LABORATORY Ili$'I'ING...........................................................................................................
.. - - 3
5. GEOLOGIC AND SOILS CO\DFI'R)NS.........................................................................................................3
5.1 GENERAL.............................. .. ....... ... ... . . ...........................................................3
.i. l.1 Undocunlcnrrd Fill .... .... ........ .. .... ...........................
.... ... ...3
i. l.1 Oldoo- Al(uvimn ................................................
........ . 3
5.1 SURI'ACI: AND GROUNDWATER.............................................................. ....... ....-
.... . ..... ... ............ -4
5.3 FAULTING AND SEIS\IICITI................ ........ .. .. ......_................... ........................................................
0
j.3.1 coleral Sri.,nucil-v - . . ... .... .... .. _ .
.. . ._... . - Y
54 LIQUEFACTION POTENTIAL ............. ........ ... .....................................................................
l
SSOFHERSEISMIC HAZARDS..............................................................................................
...................5
6. CONCLUSIONS ANDRECOJI:SIENDATIONS..............................................................................................6
6.1 GENERAL DISCUSSION .......... ....................... ........................................................
....................6
62 EAR 'FH\PORI:CONSTRUCTION ................. ...................................................................
.._. .. .... ................ .6
6.1.1 Site Clearing and Prumcrion ......_.....................................................
. _..........6
6.11 Lxcavannn Characrrricucc...... ..._...............................................................
6
6.2 3 Fill.........._..........._.................................................. .............................
. . 7
6.1.4 Shrinkage, Bulking and Subsidence .._.. ......._ ................... ....................
........... ...7
63 DESIGN RF.COMMENDATIOM ...__ ...._. .................. ._ .... .... ........ ...........................................7
6.3.1 Gcnrral. ..... . ___........._..................................................................
7
6 3. _' corn enuonul Sluh-rn,-Geode (Option li .. .. ... .. .. . _............................
.... ... ..T
6.3.3Pu.u-mnsinncJs(uhs(Option ?) .. _. ....... .. ..............
.._.... ......._8
6 3 ./ ;Ilut mic Cbuden.umon. .. ....... ... .. .. .. .........................
.. S
6. 3. n
?Coerv
ete Cm I,,nenon<mJ p
Ce,llillI T, r ..............................................
...._.. .8
6. 3.6 Foundation Sir Hackz ...... ... ...... .. ........... ... .... ..
......................9
6. 3. i Seimnic Dc„gn Pm anaarro ........ _..... ... ..................................
...............Y
64 SOII. CORRGSI\ IT} ... .. .............._. ... ............... ..... .. ..
....... ..........9
6.5 PREI.InuNAR) PAVEMEN-F DESIGN. ...... .........
.... ...... ,........ ... .... -10
6.6 RET\I\ISGWALL DESIGN AND CONS FRICIION ..................................... ... .........................................Il
6.61 Gcnoal Dc.,,g,r Criteria ....... . .. .. .. ..... ....
...... ... .. .!l
6.6? Il tdl Hmrkiill and Dicunu,r_ _.. . .._ ..... . . . .......
... ..........11
6.7 UTILIIIGS ...........................`.. .. .. ............ .... .- ... I .....................
. .. .....12
6 S SITE DRAINAGE ........... ._._... ... ........... _..................................... ... ...
... ..................12
69 PLAN RE\'IE\\'ANDCONS FRUCIION OBSER\\TIONS ...............................................
.......12
7. I_I::NI I'I ATIO.NS...................................................................................................................................................
IJ
8. 51: I.I:C-I'I:D 12I:FE12ENCLS............................................................................................................................. 15
ENCLOSURES
Fiaurc I - Site Location.Map
Fi_urc 2- Bonne Location Plan
\pPrndn A - Lugs of F\pinmton• Bonn
Apocndi\ B - Rcsulc� of Laboratory Tempa
Anncndi.x C - COmpurer Pnntout: of Seixnic .4n;dysiN
rpa,di\ D - Gencml Gradin_ Guiddmc< rix Emh„ork Consmictiun
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`1`v EIC, INC.
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Rauch Development Project 3032SD3
Prelnninary Geptrchnical Ecaluanon \lac 3. 2006
Proposed Re�idemial Development Page I
1. INTENT
It is the intent of this report to aid in the desi ri and completion of the proposed development.
Implementation of the advice presented in Section 6 of this report is intended to reduce risk
associated with construction projects. The professional opinions and geotechnical advice
contained in this report are not intended to imply total performance of the project or guarantee
that unusual or variable conditions will not be discovered during or after consu-uction.
The scope of our eVmluation is limited to the area explored, which is shown on the Boring
Location Plan (Figure 2). This evaluation does not and should in no way be construed to
encompass any areas beyond the specific arca of the proposed construction as indicated to us
by the client. Further, no evaluation of any existing site improvements is included. The scope
is based on our understanding of the project and the client's needs, and geotechnical
engineering standards nonmally used on similar projects in this region.
2. PURPOSE AND SCOPE OF SERVICES
The purpose of our study was to evaluate the general overall -cotechnical conditions on the
site as they relate to the proposed development. Services provided for this study consist of the
following:
Research and review of available geologic data and general information pertinent to the
site.
Field reconnaissance ofthe site to evaluate the general surface conditions.
Site exploration consisting of the excavation, logging, and sampling of 3 exploratory
bonngs within the arra proposed for development.
Laboratory testing rnt represcntatiVe samples collected during the field evaluation.
> Re\ ic%v and evaluation of site seismi6ty.
Compilation of this geotechnical report. Which sunumarires our findings and foundation
recommendations for the proposed development and associated site Improvements.
EK,
INC.
0 0
Ranch Development Project 3032SD3
Prehminarc Geotcchmcd Evaluation May 3. 2006
Proposed Residential Development Pike 2
3. SITE DESCRIPTION AND PROPOSED DEVELOPMENT
3.1 SITE DESCRIPTION
The subject site is located to the northwest of the intersection of Second and \Mercedes St7ects
in the City of Temecula. California (see Figure 1). The property is a rectan.,ular shaped parcel
measuring approximately 1/2 acre and consists of two individual parcels (APN T922-043-12
R 17). The site is currently under lease to Temecula \Marine, a boat sales and service business
which occupies an approximate 3500 square foot building located in the S\V quarter of the lot.
The overall site is relatively flat with a small slope (<5 feet) along the north-west property line
and an 3-10 foot slope with a 4-5 foot block keystone wall along the south-east property line
bordering iviercedes Street. The site is bordered to the northwest by a vacant lot and to the
south -%\est by Second Street. Further information regarding existing site features and layout is
shown on Figure 2.
3.2 PROPOSED DEVELOPi\IENT
Based on the information provided to us, it is our understanding that the proposed site will be
developed into a 3 -story residential structure including a subterranean floor and other related
site improvements. such as parking lots and strive areas. Buildings are expected to be founded
at approximately 10 feet belomw existing site grades with typical structural loads. If final site
or foundation plans significantly differ form the assumptions made herein. our
recommendations included in Section 6 of this report should be subject to further review and
evaluation.
4. FIELD EXPLORATION AND LABOR-1TORY TESTING
4.1 FIELD EXPLORATION
Our subsurface evaluation consisted of the excavation of 3 exploratory borings performed on
April 38. 3006 utilizing a truck mounted drill rig. The borings were excavated to a maximum
depth of 50 feet below existing site grades. The borings mmcrc logged and sampled by an
engineer from our firm. Representative bulk and relatively undisturbed samples of the
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EK, INC.
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Ranch Development Project 3032SD3
Pie inunary Geotechnical E\'alnaI ion \lav 3. 3006
Proposed Ke..tdential Deve I'll, Elie ni P2ee 3
utaterials encountered were collected and transported to our laboratory for Further testing. The
logs of borings and additional intormation rc uardins field sampling and testing procedures arc
presented in Appendix A.
4.2 LABORATORY TESTING
Laboratory testis, was performed on selected disturbed and relatively undisturbed samples
collected Burin the field cyaluation. The purpose of the laboratory testing was to confinn the
field classification of the soil materials encountered and to evaluate their physical properties
for use in the engineering design and analysis. The results of the laboratory -testing program
aloin.- with a brief description and relcNant information rcgardin- testim.- procedures are
included in Appendix B.
5. GEOLOGIC AND SOILS CONDITIONS
5.1 GENERAL
A brief description of the earth materials encountered is presented in the following sections.
\lore detailed descriptions of these materials are provided on the logs of exploratory borin -s
included in Appendix A. Basal on the results of our evaluation: the site is underlain to the
maxialU n depth explored by alluvial materials consisting mostly of silty fine sands and fine
sandy silts with settle clay.
5.1.1 Undocumented Fill
The site is mantled with a layer of undocuntental fill materials that vary in deptlu between
approximately 2 and 4 feet. These materials are described as brown, clamp to moist, medium
dense, silty sands with traces or rootlets. These materials appear to hat -e been generated durine
past gradin, activities on this site or fiorn adjacent properties.
5.1.2 Older Alluvium
Quaternary -ase older alluylum underlies the subject site. In general. these materials are
comprised of loose to dense silty sands with minor interbeds of sand- silt and clayey silt.
Based our experience with similar soils, the onsite materials can be expected possess a low
expansion potential (O<Elvl) in accordance with "Table IJ -1-B of the 2001 California
Building Code (CBC).
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�. EK, INC.
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Ranch Development Project 3032SD3
Preliminary Geotechnical Evaluation May 3. _1006
Propotcd Re>tdemial Development Paye 4
5.2 SURFACE AND GROUNDWATER
No Sol face water or ponding was observed at the time of the field et aluation. All site drainage
Should be re%iewal and designed by the prgject civil enuineer.
Groundwater was encountered in borings B-1 and B-2 at depths 29 feet below existing grades.
Groundwater was not encountered m Boring B-3. Changes in uruundwater depth or localized
seepage can occur clue to variations in rainfall, irrigation practices, and other factors not
evident at the time of this evaluation.
5.3 FAULTING AND SEISMICITY
5.3.1 General Seismicity
The site is in a seismically active region. No active or potentially active fault is known to exist
at this site. The site is not situated within an Alquist-Priolo Earthquake Fault Zone (Special
Studies Zone).
The computer program EQFAULT (Blake. 2000a) was used to detennine the distance to
known faults and estimate peak around accelerations based on a deterministic analysis. The
Elsinore -Tenacula Fault located approximately 0.5 mile from the site is considered to
represent the highest risk to venerate ,round shaking. A maximum earthquake magnitude of
6.8 and an estimated peak site acceleration of 0.55.- are pustulated based on the analysis.
The wmputer program FRISKSP (Blake, 2000) was also used to estimate peak horizontal
ground acceleration (PHGA) based on a probabilistic analysis. The results indicate that PHGA
values on the order of 0.73g may be generated at this site. These talucs correspond to a 10
percent probability of cxcecdance in 50 years (or a 475 year return period). Computer printouts
of the :uudysns along with a list of nearby faults are included in Appendix C.
5.4 LIQUEFACTION POTENTIAL
LiqucFaction occurs when saturated tine sands and silts lose then' physical su'cngths when
subjected to earthquake shaking. Liquetaction potential is primarily affected by material
gradation, relative dcnsnv, and intensity and duration of ground motion.
We have evaluated the potential for liquefaction at the site in accordance with the procedure
recommended by The National Center For Earthquake Engineering Research (YOUd, et al.
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Ranch Development Project 3032SD i
Preliminary C,eotecltnictl [valuation May 3. 2006
Proposed Residential Development Poet 5
2001). Our evaluation incorporates prin arih the geotechnical data obtained tram our
exploratory Boring B-1 and utilizes the earthquake induced _rowed motion haVilla 10 percent
probability of ezceedance in 50 years (47;-vear return period). Depth to groundwater was
assumed at 29 feet.
The results of the analysis, as shown on Plate LQ -t, indicate that the liquefaction -induced
settlement is expected to be 3.3 inches. Due to the depth of the liquefiable layers and relatively
homugenous soil conditions. the liquefaction -induced settlement is expected to be relatively
._lobal and uniform on this site.
Lateral spreading is not expected on this site due to the relatively flat topography and absence
of alnv significant channels or other free faces in the immediate vicinity of the site. Thus. it is
our opinion that the potential for liquefaction -induced lateral spreading at the site is relatively
low.
5.5 OTHER SEISMIC HAZARDS
As discussed previously. the site is relatively level Nyrth no significant slopes on or directly
adjacent to the site. Thus, the potential for landslides or slope instability is considered low at
this site.
The potential for secondary seismic hazards such as seiches and tsunamis are considered to be
negligible clue to the site's elevation and distance from an open body of water.
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Ranch Development PrQlect 3032SD3
Prehminan•Geotedmical Baluaaon \lac 3.'_006
Proposed Residenual Development Pane 6
6. CONCLUSIONS AND REC0!N7i\IENDATIONS
6.1 GENERAL DISCUSSION
The proposed development of the site appears feasible from a geotechnical viewpoint
provided that the following recommendations are incorporated into the design and
construction phases of development.
6.2 EARTtINVORK CONSTRUCTION
Grading and earthwork should be performed in accordance with the City of Temecula grading
ordinances. applicable provisions of the 2001 California Building Code (CBC), and our
recommendations presented herein.
6.2.1 Site Clearing and Protection
The site should be cleared of vegetation, roots, existing pavement/structures, or any other
deleterious materials and properly disposed of offsite. Any holes restating from site clearing
attributed to removal of trees or underground structures/utilities should be replaced with
properly compacted low expansive till materials. The earthwork contractor should take all
precautions deemed necessary during site gradim; to maintain adequate safety measures and
working conditions. All applicable safety requirements of CAL -OSHA should be met during
construction.
6.2.2 Excavation Characteristics
Excavations in the site materials within the depth explored should be generally accomplished
with conventional earthmoving or excavating equipment. Temporary excavations within the
onsite tbnnational materials should be stable at 1 H:I V inclinations for short durations clurine
construction. and where cuts d0 110t exceCd Ill feet in heieht.
6.2.3 Removals/Over-excavation
If not removed by the proposed aradina. the upper 4 feet of surticial materials) on this lot
should be removed and recompacted within the limits of proposed improvements. The intent
of this recommendation is to bring near -surface soils back to at least optimum moisture
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Ranch Development Project 3032SD3
Prelunman Geotechnical E\alutuon \lav_ 3.'_006
Propo,ed Residenual Dacelooment Page 7
content, and re -compact the soils to 90% (ASTM D-1557) relative compaction or higher.
Depending on actual field conditions encountered during grading, locally deeper areas of
removal may be required.
6.2.4 Fill
The onsite materials are considered suitable for reuse as compacted till provided they are free
from vegetation. cobbles/debris greater than 6 inches in diameter. The earthwork contractor
should ensure that all proposed excavated materials to be used for backfilling at this site are
approved by the soils engineer. All import till should consist of relatively (Uranular. low
expansive soils (EI<5I ) and be evaluated by our hnn prior to arrival at the site. The undercut
or till areas should be brou.,ht to final subgrade elc\ations \Nith till placed in 8 -inch lifts and
compacted to a minimum of 90 percent relative compaction as determined per ASTM Test
D-lethod D 1557-00.
6.2.5 Shrinkage, Bulking and Subsidence
Shrinkage, bulking and subsidence are primarily dependent upon the degree of compactive
effort achieved during construction. For planning purposes, a shrinkage factor of 10 % to 20%
may be applied for the alluvial/till materials requirin, removal and recompaction.
Additionally, subsidence will occur as a result of compaction below the removal bottom or
surcharging. This could ran,_c from 0.1 to 0.2 feet (1101 including dynamic settlement).
The above estimates are intended as an aid for project en.-incers in determining earthwork
quantities. It is recommended that site development be planned to include an area that could
be raised or lowered to accommodate final site balancing.
6.3 DESIGN RECONIiNIENDATIONS
6.3.1 General
Foundation design recommendations for slab on grade systems arc presented herein. These arc
typical design recommendations and are not intended to supersede the design by the structural
engineer.
6.3.2 Conventional Slab -on -Grade
For construction of a conventional slab -on -grade foundation system on this site we
recommence An allowable bearing, capacity of 2500 pounds per square foot (I)St). mcludin=11
both dead and live loads, may be used for design of tOundations founded into compacted till
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*ECOI K, INC.
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Ranch Development Project 3032SD3
Preliminanv Geotechmcnl Evaluation \lay 3. 7006
Proposed Residential Development Paue S
or dense onsite soils at a depth of at least 3 feet below existing wades. The passive resistance
may be computed as an equivalent fluid pressure haeing a densit of 300 psf per foot of depth.
to a maximum earth pressure of 3500 psf. A coefficient of fiction between soil and concrete
of 0.4 may be used with dead load forces. When combining passive pressure and frictional
resistance, the passive pressure component should be reduced by one-third. The above
allowable pressures may be increased by one-third when considering shoe -terns live loads
(e.g, seismic and wind loads).
6.3.3 Settlement
Based on the above. the post -grading differential settlement is expected to be less than l inch
over a 40 -foot span under static conditions and less than 2 inch over a 40 -foot span under
seismic loading.
6.3.4 Moisture Condensation
Where moisture condensation is undesirable. all slabs should be underlain with a minimum
10 -mil polyvinyl chloride membrane, sandwiched between to layers of clean sand (SE above
?i) each being at least two inches thick. Care should be taken to adequately seal all seams and
not puncture or tear the membrane.
6.3.5 Concrete Construction and Cement TN pe
Concrete construction should follow the CBC and ACI guidelines regarding design. mix
placement and curing of the concrete. If desired. we could provide quality control testing of the
concrete during construction.
The sulfate content was determined in the laboratory for representative onsite soil samples.
The results indicate that the water-soluble sulfate is less than 0.1 percent by weight. which is
considered negligible as per Table 19-A-4 of the CBC. Bascd upon the test results. type II
cement of an equivalent may be used.
Concrete slabs and all exterior concrete tlatwork (patios, walkways, driveways. etc.) should be
designed to resist shrinka ze cracking. One of the simplest means to control cracking is to
provide weakened joints. These do not prevent cracks font occurring but they simply provide
a relief point I'm the stresses that develop. These joints are widely accepted means to control
cracks but are not always eftective. Control joints are more effective the more closely spaced.
It has been a standard care that control joints be placed in two directions spaced the numeric
equivalent of two times the thickness of the slab In inches changed to feet (e.g. a 4 inch Blah
would have control joints at 3 feet centers).
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, EK, ZINC.
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Ranch Development Project 3033SD3
Preliminan' Geotechnical Evaluation Ma\ 3. _'006
Proposed Restlennal De\elopment Pace 9
6.3.6 Foundation Set Backs
%\,here applicable, the tollo\wing foundation setbacks should apple to all foundations. Any
impt-mements not confornung to these setbacks may be subject to lateral movements and'or
differential settlements:
6.3.6.1 The outside bottom edge of all foitim s should be set back a minimum of H/3 (\\,here
H is the slope height) front the face of any descending slope. The setback should be at
least 7 fed and need not exceed 20 feet.
6. 3.6 2 The bottom of all footings for structures near retaining walls should be deepened so as
to extend below a I:I projection upward tiom the bottom inside edge of the wall
stem.
6.3.6.3 The bottom of any existing foundations for structures should be deepened so as to
extend belo\v a I:I projection upward fiom the bottom of the nearest excavation,
otherwise any additional loads induced by the existing foundations should be
considered in the design of the shorin.- system or the underground retaining structure.
6.3.7 Seismic Desi -n Parameters
SeismicalIv resistant structural design in accordance with local building ordinances should be
follo\ved during the design of all structures. Building Codes have been developed to minimize
structural damage. However. some level of dama-e as the result of ground shaking generated
by nearby earthquakes is considered likely in this general area.
For the purpose of seismic design a Type A seismic source 0.3 kin from the site may be used.
Sho\vn in Table 6.2. t below are seismic design factors in keeping with the criteria presented
in the 2001 CBC. Division IV S-, V. Chapter 16.
TABLE 6.3.1 — SEISMIC DESIGN PARAMETERS
Soil Profile
Parameters 7\ e
.1
C�
�\'�
N�
Sci5111ic
Source 1 \' )e
Source Table I 161
I 16Q
16R
I6S
IGC
16U
Value Si)
0.66
128
1.5 I
2.0
A
6.1 SOIL CORROSIVITY
The soil resistivity at this site was tested in the laboratory on a repicsentati\e sample collected
during the field e\aluatlon. The results of the testing are included in Appendix B. It is
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EK, INC.
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Ranch Development Project 303'-SD3
Preliminary Geotechnical EN alnattOn \tax, 3. 1006
Proposed Residential Det elo mens po,e 10
recommended that a corrosion engineer be consulted to provide reconnncridatioils for proper
protection of buried metal pipes at this site.
6.5 PRELIMINARY PAVENIENI' DESIGN
The pavement sections presented below are calculated based on the design standards included
in the California Department of Transportation -Highway Design \Manual", fifth edition and
utilizing an assumed R -Value of 30. We recommend that laboratary testing be performed at the
completion of site gradin_ to Verify the actual subgrade conditions. The pavement sections
below can then be increased or reduced based on actual R -values obtained.
TABLE 6.1.1 — PRELIMINARV PAVEMENT DESIGN
AC is asphalt concrete confomting to Section 39 of Cahrans General Spec licm ions.
AB is aLueuate base millomting to the requirement, of C'altran 'Class 11 Aggregate Base'.
The top 11 inches of the subgrade and all aggregate base should be properly moisture
conditioned and compacted to a minimum relative compaction of 95 percent of the laboratory
dry density as determined by .-1ST\M D 1557-00, We recommend that a minimum of 3 feet of
removal and recompaction be performed beneath all paved area and exterior tlaheork. If
adverse conditions are encountered during preparation of subgrade materials. additional
undercutting and removal of unsuitable materials may be required.
A 6 -inch thick section of Portland Cement Concrete (PCC) pavement can be used in heavy
truck traffic areas such as fire lanes, and cash dumpster pads and approaches. The PCC
pavement ❑ ay be placed directly on top of compacted subgrade havins a minimum R -value of
25. The PCC pavement should be adequately reinforced to prevent shrinkage cracking and
have a mhllmum of 38 -day flextual strength of 050 psi. Other requirements of Section 90 of
C'altran Standard Specifications reg:u'ding mixing and placing concrete should be followed.
Keyed joints should be provided in the lonuitudinal direction spaced it a maXtmum of 10 feet
on center. Crack control joints should be provided in the transverse direction spaced at a
maxinmum of 10 feet on center and at comers.
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Recommended Pavement
Street Type
Traffic Index
Section (Inches)
Automobile DriN im and Parkinu
4.5
3 AC / 6 AB
Heavy Traffic Driveways
6.0
a AC / 6 AB
AC is asphalt concrete confomting to Section 39 of Cahrans General Spec licm ions.
AB is aLueuate base millomting to the requirement, of C'altran 'Class 11 Aggregate Base'.
The top 11 inches of the subgrade and all aggregate base should be properly moisture
conditioned and compacted to a minimum relative compaction of 95 percent of the laboratory
dry density as determined by .-1ST\M D 1557-00, We recommend that a minimum of 3 feet of
removal and recompaction be performed beneath all paved area and exterior tlaheork. If
adverse conditions are encountered during preparation of subgrade materials. additional
undercutting and removal of unsuitable materials may be required.
A 6 -inch thick section of Portland Cement Concrete (PCC) pavement can be used in heavy
truck traffic areas such as fire lanes, and cash dumpster pads and approaches. The PCC
pavement ❑ ay be placed directly on top of compacted subgrade havins a minimum R -value of
25. The PCC pavement should be adequately reinforced to prevent shrinkage cracking and
have a mhllmum of 38 -day flextual strength of 050 psi. Other requirements of Section 90 of
C'altran Standard Specifications reg:u'ding mixing and placing concrete should be followed.
Keyed joints should be provided in the lonuitudinal direction spaced it a maXtmum of 10 feet
on center. Crack control joints should be provided in the transverse direction spaced at a
maxinmum of 10 feet on center and at comers.
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0 0
Ranch Development Project 3033SD3
Prehminary Geotechnical [valuauun Nlav 3, 1006
Proposed Residenual Development Paae I1
6.6 RETAINING WALL DESIGN AND CONSTRUCTION
6.6.1 General Design Recommendations
Recommendations presented herein may apply to typical masonry or concrete vertical
retaining walls to a maximum hcieht of 10 feet. Additional review and recommendations
Should be requested for higher walls.
Retaining scalls embedded a minimum of IS inches into compacted till or dense compacted
materials should be desi.-ned using a net allowable bearing capacity of 3;000 psf. An increase
of one-third may be applied when considering short-term live loads (e.(,. seismic and wind
loads). The passive earth pressure may be computed as an equivalent fluid having a density of
350 psf per foot of depth, to a maximum earth pressure of 3,500 psf. A coefficient of friction
between soil and concrete of 0.35 may be used with dead load forces. When combining
passive pressure and frictional resistance, the passive pressure component should be reduces]
by one-third. An cquivalcnt fluid pressure approach may be used to compute the horizontal
active pressure against the wall. The appropriate fluid unit weights are given in Table 6.6.1
below for specific slope gradients of retained materials.
TABLE 6.6.1 —ACTIVE EARTH PRESSURES
Surface Slope of Retained \Materials (I l:V)
Equivalent Fluid Pressure(PCF)
Level
35
2:1
45
The above equivalent fluid weights do not include other superimposed loading conditions such
as expansile soil, vehicular traffic, structures, seismic conditions or adverse .,eolo,,ic
conditions.
6.6.2 Wall Backfill and Drainage
The onsite low expansive soils are suitable for backfill provided they are screened of -reater
than 3 -inch size travels. Presence of other materials might necessitate revision to the
parameters provided and modification of wall designs. The backfill materials should be placed
in lifts no greater than S-inclics in thickness and compacted at 90 percent relative compaction
in accordance with ASTM Test itMethod DI�57-00. Proper surface drainage needs to be
provided and maintained.
Retaining walls should be provided with all adcquatc pipe and gravel back [lain system to
present build up of hydrostatic pressures. Backdrains should consist of a 4 -inch diameter
perforated collector pipe embedded in a minimum of one cubic toot per lineal foot of 3/8 to
EQ
EK, INC.
0 0
Ranch Development Project 3032SD3
Preliminary Geotechnical E%airmion Ma%3. 3006
Proposed Residential Dex'elopment Paee I?
one inch clean crushed rock or cquiyalent. wrapped in filter fabric. The drain system should be
connected to it suitable outlet. A mininuttn of [w0 outlets should be provided for each dram
section. Walls from ? to d feet in height may be drained using localized gravel packs behind
weep holes at 10 feet maximum spacing (e.g. approximatelc 1.5 cubic feet of Gravel in a
woven plastic ba_) Weep holes should be prodded or the head joints omitted in the test
course of block extended above the unround surface. However. nuisance water may still collect
in front of wall.
6.7 UTILITIES
As discussed previously, the project site appears to be susceptible to liquefaction and a
considerable amount of seismically -induced settlement. Consequently, consideration should be
given to "flexible" (lesign for onsite utility lines and connections.
Except where extending perpendicular to/under proposed foundations, utility trenches should
be constructed outside a L 1 projection from the base -of -foundations. Trench excavations for
utility lines that extend under structural areas should be properly backfilled and compacted.
Utilities should be bedded and backfilled with clean sand or approved granular soil to a depth
of at least l400t over the pipe. This backfill should be uniformly watered and compacted to a
fimi condition for pipe support. The remainder of the backfill shall be typical on-site soil or
imported soil which should be placed in lifts not exceeding 8 inches in thickness, watered or
aerated to 0 to : percent above the optimum moisture content, and mechanically compacted to
at least 90 percent of maxinwm dry density (based on AST\4 1)1557).
6.8 SITE DRAINAGE
The need to maintain proper surface and subsurface drainage systems cannot be overly
emphasized. Surface water should not be allowed to pond and should be directed away From
foundations and hardscape.
6.9 PLAN REVIEW AND CONSTRUCTION OBSERVATIONS
We recommend that site a adin_, specifications, and foundation plans be reviewed by this
office prior to construction to check for conformance with the recommendations of this report.
We also recommend that geotechnical representatiNes be present (fining site gradate and
foundation construction to check for proper implementation of the ueutechnical
recommendations. These representatives should perform at least the following duties:
t EEK, II`C.
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Ranch Development Project 3031SD3
Prehmmara Geotechnical I:caluauon May 3. 1006
Proposed Residential Development Pa,,e 13
• Observe bottom of removals prior to fill placement.
• Evaluate the suitability of on-site and import materials for till placement, and collect soil
samples for laboratory testis u «$ere necessan.
• Observe the till for unifoniity during placement inclLldin_ utilitV trenches. Also, test the
fill for field density and relative compaction.
• Obsene and probe foundation materials to continn suitability of bearing materials and
proper footing dimensions.
If requested. GcoTek will provide a construction obsen ation and compaction report to comply
with the requirements of the governmental agencies haying jurisdiction over the project. We
recommend that these agencies be notified prior to commencement of construction so that
necessary grading permits can be obtained.
O
0 0
Ranch Development Project 3033SD3
Preliminary Geotechnical Evaluation \laN 3. 1006
Proposed Re>idential Development Pi --,e 14
7. LINIITATIp\S
The materials observed on the project site appear to be representative of the area: however,
soil and bedrock materials vary in character between excavations and natural outcrops or
conditions exposed during site construction. Site conditions may vary due to seasonal changes
or other factors. GeoTek, Inc. assumes no responsibility or liabilih_- for work. testing or
recommendations performed or provided by others.
Since our recommendations are based upon the site conditions observed and encountered, and
laboratory testing, our conclusions and recommendations are professional opinions that are
limited to the extent of the available data. Observations eluiing construction are important to
allow for any change in recommendations found to be warranted. These opinions have been
derived in accordance xvith current standards of practice and no warranty is expressed or
implied. Standards of practice are subject to change with time.
"
(rL,ECO
`',� EK, INC.
4
0 0
Ranch Develop men( Project303'_SD3
Prclinunan, Geotechnical Evaluation Alar 3. 2006
Proposed Residential De\elomnem Paee IS
8. SELECTED REFERENCES
Afrouz, A.. 1992. "Practical !-landbook of Rock Mass Classifications Systems and Modes of Ground
Failure". CRC Press. January 1992.
ASTM. 200. "Soil and Rock: American Society for Testine and Materials.' col. 4.O8 for ASTNI test
methods D-420 to D-4914. 153 standards. 1.026 pages: and col. 4.09 for ASTNI test method D-
4943 to hiehest number.
Blake, T.. 2000a, " EQFAULT, version 3.00 a Compu(er Program for Dete(muntstic Estimation of
Maximum Earthquake Event and Peak Ground Acceleration.
Bowles, J., 1982, "Foundation Analysis and Desi,nt McGraw-Hill, Third Edition.
California Code of Regulations, Title 24. 2001 "California Building Code (CBC).-- 3 volumes.
C'aliforma Division of Mines and Geology (CD\9G). 1997. "Guidelines for Evaluatin.- and Zvliti�ating
Seismic Hazards in California." Special Publication 117.
California Division of Mines and Geolog} (CDMG). 1995, Maps of Known Active Fault Near -Source
Zones in Califontia and Adjacent Portions of Nevada: International Conference of Building
Officials.
GcoTek, hoc., In-house proprietary nil'ormanon.
Ishihara. K., 1985. "Stability of Natural Deposits During Earthquakes Proceedings of the Eleventh
Intentational Conterence on Soil Mechanics and Foundation Eneuiecrur_. San Francisco. CA,
Volume 1.
Seed, H B.. and Idris. I.M., 1952. "Ground \-lotions And Soil Liquefacliou During Earthquakes'."
Earthquake Engineering Rescatch lnsnlnte.
Sccd. H.B., and'fokimatsu, K. Harder. L.F.. and Chune. R.NL. 1955. "Inllucnce of SPT Procedures m
Soil Liquefaction Resimance Evaluations,' Journal of the Geotechnical Engureerimt Division.
American Society of Civil Engineers. vol. I 11. no. GTI2. pp.1425-1445.
Ian, S.S. and Kennedy. i\1 P.. compiled 1999. California Division of \-lines and Geology (CDNIG),
Geologic Map of the Temecula Ti' Quadrangle. Riverside Countv. California: A Digital
Database.
N oud. T. Leshe and Idriss, Izzmat NJ.. 1997. Proccedmg of the NCEER \Vorkshop on Evaluation of
Liquefaction Resistance of Soils. National Center lin' Earthquake Engineering Research. Technical
Report NCI -1-R-97-002'.
food. T.L. ct al . 2001. Pi'oceedmg of the NCE ER Workshop on Evaluation of Liquefaction Resistance
of Soils. National Centel' for Earthquake Engineering Research.
r,
CO
EK, INC.
0 9
T
Source: Thomas Brothers Guide, 2006 Edition
Ranch Development
Proposed Residential Building Figure 1
41923 Second Street Site W",N
Temecula. California 92590 VVV LocationEKEC•
tMap 1334 Poinsettia Avenue, Suite A
GeoTekNm,hrr 303'SD3 Vista. California 92031-3505
i
T
Source: Thomas Brothers Guide, 2006 Edition
Ranch Development
Proposed Residential Building Figure 1
41923 Second Street Site W",N
Temecula. California 92590 VVV LocationEKEC•
tMap 1334 Poinsettia Avenue, Suite A
GeoTekNm,hrr 303'SD3 Vista. California 92031-3505
" • • •
Source: Site plan by Riverside County GIS.
Ranch Development FIGURE 2
Proposed Residential Building
41923 Second Street Boring
Temecula, California 92590 Location
Geo Tek A4ueber: 3031SD3 Plan
LEGEND
B-3 j App eminate Ic ation of e\plonton small borin_s
WEK, INC.
1334 Poinsettia Avenue, Suite A
Vista, California 92031-3505
11
APPENDIX A
LOGS OF EXPLORATORY BORINGS
(BORIN(;S Bl THROUGH B3)
RANCH DEVELOPMRNT
PROPOSED RESIDENTIAL DEVELOPMENT
PROJECT No. 3032SD3 3032SD3
7
Ranch Development
n
u
APPENDIX A
Preliminary Geotechnical Evaluation Project 3032SD3
p cedsppa Residential Dovelanmont _ 11—Al
LEGEND FOR FIELD SAMPLING AND TESTING PROCTDURES
A - FIELD TE&YING AND SAMPLING PROCF,DURES
The Standard Penetration Test (S19
The SPT is performed in accordance with ASTM Test Method D 1586-99, The SPT sampler is
typically driven into the ground 12 or 18 inches with a 140 -pound hammer free falling from a height
of 30 inches. Blow counts are recorded for every 6 inches of penetration as indicated on the log of
boring. The split -barrel sampler has an external diameter of 2 inches and an unlined internal diameter
of 1-318 inches. The samples of earth materials collected in the sampler are typically classified in the
field, bagged, sealed and transported to the laboratory for further testing.
The Modified Split -Barrel Sampler (RuiO
The Ring sampler is driven into the ground in accordance with ASTM Test Method D 3550-84. The
sampler, with an external diameter of 3.0 inches, is lined with 1 -inch long, thin brass rings with inside
diameters of approximately 2.4 inches. The sampler is typically driven into the ground 12 or 18
inches with a 140 -pound hammer free falling from a height of 30 inches. Blow counts are recorded
for every 6 inches of penetration as indicated on the Ing of baring.lhe samples are removed from the
sample barrel in the brass rings, scaled, and transported to the laboratory for testing.
Bulk `Large' Samples
Bulk samples are normally bags of representative earth materials over 20 pounds in weight collected
from the field by means of hand digging or exploratory cuttings.
Bulk `Small Plastic Ban' amnles
Plastic bags samples are normally airtight and contain less than 5 pounds in weight of representative
earth materials collected from the field by means of hand digging or exploratory cuttings. These
samples are primarily used for determining natural moisture content and classification indices.
B — BORING LOG LEGEND
The following abbreviations and symbols often appear in the classification and description of soil and
rock on the logs of borings:
SOILS
USCS
Unified Soil Classification System
f -c
Fine to course
f -m
Fine to medium
is LAIC
B: Attitudes
Bedding: strike/dip
]: Attitudes
Joint: strike/dip
C:
Contact line
...........
Dashed line denotes approximate USCS material change
Solid Line denotes approximate unit / formational change
Thick solid line denotes approximate end of boring/trenchas
(Additional denotations and symbols are provided on the Ings of boring?/trenches)
F
`NZ.: •
ON'$ t
0
GeoTek, Inc.
LOG OF EXPLORATORY BORING
CLIENT: Ranee Da W Wl DRILLER: CRlpac LOGGEDBY: BD aLG
PROJECTNAMM 2adehae9t DRILLMETH00: WHOMSIMAINK OPERATOR: J.RBRan
PROJECTNO.: OD32803 HAe1MER: taohmh, RIG TYPE: Mama 50
LOCATION: Bao SRO Nen DATE: 1119120Ce
Laboratory
Testing
6AMPIEs
.c
BORING NO.: B-1
MATMAL DESCIOPTIM AN13 COMMENTS
81-1
SM
T eo
Dark Brown, moist very loose, silty fine SAND
MD
3
Atlw
3
SM
Dark brown, very metal achy ran SAND; wdh some clay d trace
119
111
6
B1-2
5
3
05. becomes brown, moist, loose. Stay fine SAND with clay and
16.2
114
SH
8
91-5
ootlets
4
4
-same
6
8
B1.4
10
b
CID% becomes loose to medium dense, Secy fine_ SAND with clay
las
7
91.5
11
15
4
4
S"
carne
18.3
6
20
2
5
61-7
-Same
18.6
6
§241: gravel layer
25
—
..__.
.....__....___—__....-_.__—___..__._._...__.._-..�._.._.._._.._.
_...._.
dense, fine to madmen sand
.__._
8.6
—__... ... ............ __._..-._.
j
Light brawn, sllghty moist msdlum
11
Bt -8
SP
11
(CONTINUED)
�
�arnGS: iVDB: —f E,9 —�T �'""amallBWs ®—Lwpa 9uk � -Na Reeway �—dNundtvaler iGw)
�sAllarBerD LRma EI-Et@aaalon lodes SA.66@w Am"I. RJ- R-Veluo TaR
Lab teB[InD:
SR -F& a0l1R ahulNre SH -Spear Test CO= CcaeddagM IN[ MD - FAXIMM Dansny
0 0
GeoTek, Inc.
LOG OF EXPLORATORY BORING
CLIENT: RNaa D,NNoammt ORILLBR: calow LOOOED BY: 608 LO
PROJECT NAME: 2n46101ee1 um"UOTHOD: VtftJm6Wm Awa OPERATOR J.A.&Ken
PROJECTNO.: 3=SD3 t1AMM£R 140ppaa RIO TYPE Mottle W
LOCATION: nee sva ran DATE. 49914900
Loborato
Teatln
6
'k
p$
2A§
BORING NO.: B•1 (Cont.)
y�
g
o
3
'g
MATERIAL DESCRIPTION DCOMM—
All m
SP
Yelow_wet, medium dense_flne to medium SAND
30
--.—
medhan Cense, Ane fo coarse gANb'
18.3
ip
glry
-own, saturated,
13
51.9
14
11
-
,
13
_
81- 0
SMreybiowe,
..._..,., .,....._
molsi; medlmn aerlse-ifne sandyfCP�
14
40
8
8
81-11
aame
15
45
50
8
®50': becomes gray -preen, moist, medium dense, day sill; calcium
GA
11
81-12
ML
carbonate stringers
29
HOLE TERMINATED AT 51.5 FEET
Nate backRllad with soil cuttings
Groundwater encountered at 29 fast
55
Z
Rem
®—SPT Z--emtll sulk ®—L.Neaaalk El —No Rewary i--bWuntl'.�at<r (OhtT
Semple type -.-M'
testltla: AL=A1WNerg Llmlle EI•Evyendrn Npoa eA=Steve Armyels RV - RNaWP TeaI
aR=SUPal sI8 Teel am•6heer Tact CO=comalsakbnlest MD-Nw.mpamM1Y
GeoTek, Inc.
LOG OF EXPLORATORY BORING
CLIENT: Rmeh DpYkaeaMnt DRILLER: cs%.. LOGGED BY: DO LO
PRO.ECTINAM Ind &ssM DRILLMETHOD: S'Fbacw Stem Auger OPERATOR: J.RaKsn
PROJECT NO-- 3939SD3 HAMMER: 140k M RIG TYPE: M661M 63
aM" a•. es. w.. DATE: 4012005
_V V^ _•'•BAt.1PLE8
La6wet0
Testing
g o
BORING NO.: B-2
$pE;
MATERIAL DESMIPTioN AND COMMENTS I
SM
Alluvium
Brown. moist, loose, silty fine SAND
SR
82-1
2
2
B2.2
3
5
5
®S: same - Porous with (cutlets
11.4
127.2
7
7
82-3
3
3
82.4
@7.59 becomes silty itno SAND with clay and trace gravel
SR
6
10
B
@1V: becomes medlum dense
11.11
122.5
tt
B25
18
82.6
15
2
3
B2-7
5
SW`
Laht brown, moist, medlum canoe, fine to medium SAND
�
b
b
B2-8
9
25
3
SP
Gray-grean, moist, loose, the SAND
3
B29
6
increasing In mclature
(CONMUED)
®—SPT 21--em2116ue �—Larye Bulk L1 —RO Rw ery W, —d�a(GA)
Sample type: —1&®
M�
�..,i•.._ ALAitt-ULlmis E•E+pmuon Mex BA=SMue Ar..W& RV -R-Va Test
'�
t�G
BR=Su4'e/Re Test SH a shear Test CO+Cmvindeam test MD-KUAmum Oen0I
CLIENT: Rawh Dawmpnanl _
PROJECTNAME: z Hussar
PROJECT NO.: SUNSD3
LOCAMON: Seesteplen
GeoTek, Inc.
LOG OF EXPLORATORY BORING
DRILLER; Calgao
DRILLMBTHOD: VHNbwalaaa Auger
HAMMER: 140MRa
LAGGED BY: 006 LO
OPERATOR: J.R&K"
RIG TYPE: MOM853
DATE: M81=e
F
.6
y
n
G
ILaboratotvToolinn
BORING NO.; B-2 (Copt.)
g
It
ERLALRLP o—Mm
0
°
Sp
Gray�green, molSL loose, fine SAND
g
--------
6
ML
Gmy-green, mcist deme, sandy SILT
1S S
12
B210
21
HOLE TERMINATED AT 31.5 FEET
Hole backfilled with soil cuttings
Groundwater enenuntered at 29 feet
95
40
45
50
55
i�
W
Samofe WDe: —Mg 1— r Z—Sad Slee ®—targe 0uls--WRew+ery g—GmuiM18mr1Gw1
V
AL-MftwnUmhl EI=Eapanolmind GA-Sievo Ardor RVa R-VYue Teal
Labseatllm;
SR=SuftwR.dfWTeat SH-Ehwr Test CG a ConsogLaean met MD=Mmmmm Denaty
Ranch Development
APPENDIX B
Preliminary Geotechnical Evaluation Project 3032SD3
pjgposeo Residential Deveiooment Page B-1
SUMMARY OF LABORATORY TESTING
Classification
Soils were classified visually according to the Unified Soil Classification System (ASTM Test
Method D2487). The soil classifications are shown on the logs of exploratory borings in
Appendix A.
Grain size distribution (particle size analysis) was performed on selected samples in
accordance with ASfM D422. Results of grain size analysis are sbown on Plates SA -1 & 2.
In Situ Moisture and Unit Weight
The field moisture content was measured in the laboratory on selected samples collected
during the field evaluation. The field moisture content is determined as a percentage of the
dry unit weight. Results of these tests are presented on the logs of exploratory borings in
Appendix A. The results are shown on the logs of exploratory borings in Appendix A
Sulfate Can&W
Analysis to determine the water-soluble sulfate content was performed in accordance with
California Test No. 417. The results of the testing are included herein.
Resistivity
Representative surficial soil samples were collected and tested for resistivity in accordance
with California Test 643. The results of the testing are included herein.
Direct Shear Testing
shear testing was performed on undisturbed samples of site soil in general accordance with ASTM
Test Method D-3080. The test result is included in Appendix B.