0201-195 (RC) Geotechnical InvestigationGEOTECIINICAL INVESTIGATION
LA QUINTA COURT
HIGHWAY I I I AND WASHINGTON STR-EET
LA QUINTA, CALIFORNIA
— Prepared By —
Sladden Engineering
39-725 GARAND LN., SUITE G
PALM DESERT, CA 92211
(760) 772-3893
Slodden Enginseting .4
Sladden Engineering
6782 Stanton Ave., Suite E, Buena Park, CA 90621 (562) 864-4121 (714) 523-0952 Fax (714) 523-1369
39-725 Garand Ln., Suite G, Palm Desert, CA 92211 (760) 772-3893 Fax (760) 772-3895
May 8, 2000
Mr. Date Frank
c/o G. J. Murphy Construction
Post Office Box 1124
Palm Desert, California 92261
Project: La QUinta Court Retail Complex
Hiahwav I I I and Washington Street
La QUinta. California
Subject: Geotechnical Investigation
Project No. 544-0102
00-05-197
Presented herewith is the report of our Geotechnical Investigation conducted at the site of the proposed
5.5 acre commercial development located on the southeast comer of Highway I I I and WashIngoton Street
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in the City of La Quinta, California. The investigation was performed in order to provide
recommendations for site preparation and to assist in, foundation design for the proposed commercial
buildings.
This report presents the results of our field investigation and laboratory testing along with conclusions
and recommendations for foundation design and site preparation. This. report completes our original
scope of services as described in our proposal dated April 17, 2000.
We appreciate the opportunity to provide service to you on this project. If you have any questions
regarding this report, please.contact the undersigned
Respectfully submitted,
SLADDEN ENGINEEIUNG
Brett L. Andergori—
N o . C 45389
Principal Engineer
Exp. 9-30-2002
SER/pc
Copies: 8/Mr. Dale Frank c/o G. J. Murphy Construction
GEOTECHNICAL INVESTIGATION
LA QUINTA COURT
HIGHWAY I I I AND WASHINGTON STREET
LA QUINTA, CALIFORNIA
May 8, 2000
TABLE OF CONTENTS
INTRODUCTION....................................................................................................................... I
SCOPE OF WORK ...............................
PROJECT DESCRIPTION ......................................................................................................... I
SUBSURFACE CONDITIONS .................................................................................................. I
CONCLUSIONS AND RECOMMENDATIONS ...................................................................... 2
FoundationDesign .................................................................................................................. 3
Settlements............................................................................................................................. 3
LateralDesian ........................................................................................................................ 3
RetainingWalls ..................................................................................................................... 3
ExpansiveSoils ..................................................................................................................... 4
Concrete Slabs -on -Grade ...................................................................................................... 4
SolubleSulfates ............................................................................................................ ........ 4
Tentative Pavement Design .................................................................................................. 4
Shrinkaae and Subsidence ......................................................................................... I ........... 5
GeneralSite Grading ......................................... : ................................................................... 5
1. Clearing and Grubbing ................................................................................................ 5
2. Preparation of Building Areas ......................................................................... .......... 5
3
I Preparation of Surfaces to Receive Compacted Fill .................................................... 5
4. Placement of Compacted Fill ..................................................................................... 5
5. Preparation of Slab and Pavement Areas ................................................................... 6
6. Testing and Inspection ................................................................................................. 6
GENERAL........................................................................................................................... : ...... 6
APPENDIX A - Site Plan and Boring Logs
Field Exploration
APPENDIX B - Laboratory Testing
Laboratory Test Results
APPENDIX C - 1997 UBC Seismic Design Criteria
S16dden Engineering
May 8, 2000 Project No. 544-0102
00-05-197
INTRODUCTION
This report presents the results of our Geotechnical Investigation performed in order to provide
recommendations for site preparation, the design and construction of the foundations for the commercial
building planned for the La Quinta Court development. The property is.located on the southeast comer of
Highway I I I and Washington Street in the City of La Quinta, California. The associated site
improvements will include, paved driveways and parking lots, underground utilities, and landscape areas.
SCOPE OF WORK
The purpose of our investigation was to determine certain engineering characteristics of the near surface
soils on the site in order to develop recommendations for foundation design and site preparation. Our
investigation included field exploration, laboratory testing, engineering analysis and the preparation of
this report.. Evaluation of environmental issues or hazardous materials was not within the scope of
services provided. Our investigation was performed in accordance with contemporary creotechnical
e gineering principles and practice. We make no other warranty, either express or implied.
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PROJECT DESCRIPTION
The proposed project is located on the southeast corner of Highway I I I and Washington Street in the
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City of La QL[Iilta, California. The preliminary site plan indicates that the project will include 2 large
commercial bUddings along Highway I 11, a restaurant pad and a smaller commercial building along
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Simon Drive. It is our assumption that the proposed buildings will be of relatively 11,ghtweight wood-
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frarne, reinforced masonry or steel -frame construction. The associated site improvements will include
paved driveways and parking areas, landscape areas and various underground utilities.
The project site is presently vacant and the ground surface is covered with sparse short grass and weeds.
Highway I 11, Washington Street and Simon Drive are paved adjacent to the site and there are existing
underaround utilities alona the streets. Simon Motors automobile dealership forms the east edae of the
site.
Based upon our previous experience with similar lightweight commercial/industrial structures, we expect
that isolated column loads will be less than 50 kips and wall loading will be less than. 3.0 kips per linear
foot. Future grading is expected to include minor cuts and fills to canstruct level building pads and to
accommodate site drainaae. This does not include removal and'recompaction of the foundation bearing
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soils within the buildincr areas. If the anticipated foundation loading or site grading varies substantially
from that assumed, the recommendations included in this report should be reevaluated.
SUBSURFACE CONDITIONS
The site is underlain primarily by a thin profile of artificial fill soils overlying native fine-grained silty
sands and sandy silts. Recovered ring samples and sampler penetration resistance (as measured by
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blowcounts) indicate that the site soils are inconsistent in density and generally loose but density appears
to generally increase with depth.
The site soils were found to be generally dry throughout the depth of our borings but some of the deeper
silty clay layers were wet. Moisture contents varying from 0.5 to 29.0 percent were determined for the
samples obtained within our borings.
Slodden Engineering
May 8, 2000 -2- Project No. 544-01027
00-05-197
Laboratory classification testing indicates that the near surface soils consist primarily of fine grained silty
sands and sandy silts. Expansion testing indicates that the majority of surface soils are non -expansive and
fall within the "very low" expansion category in accordance with the Uniform Building Code
classification system. However, the sandy silts were found to be moderately expansive with testing
indicating expansion rates of 49 which falls within the "low" expansion category. Consolidation testing
performed on relatively undisturbed samples indicated that near surface native soils underlying the site
may be susceptible to potentially damaging settlements due to hydroconsolidation and compression.
Groundwater was not encountered in our borings and groundwater is expected to be in excess of 100 feet
below the existing -ground surface. Groundwater should not be a factor in foundation design or
construction.
CONCLUSIONS AND RECOMMENDATIONS
Based upon our field and laboratory investigation, it is our opinion that the- proposed La Quinta Court
cornmercial development is feasible from a soil mechanic's standpoint provided that the recommendations
included in this report are considered in building foundation design and site preparation. Due to the
inconsistent and generally loose conditions of the near surface soils, remedial grading includII12
overexcavation and recompaction is recommended for the proposed building areas. We recommend that
remedial grading within the proposed building areas include overexcavation and recompaction of tile
foundation bearing soils. Specific recommendations -for site preparation are presented in tile site Qradilia
section of this report.
Groundwater was not encountered within our borings and groundwater is expected to be in excess of 80
feet below the existing ground surface. Due to the depth to groundwater, specific liquefaction analyses
were not performed. Based upon the depth to groundwater, the potential for liquefaction and the related
surficial affects of liquefaction impacting the site are considered negligible.
The site is located within an active seismic area of Southern California within. approximately 9 kilometers
of the San Andreas fault. Strong ground motion resulting from earthquake activity along the nearby San
Andreas or San Jacinto fault systems is likely to impact the site during the anticipated lifetime of th ' e
structures. Structures should be designed by professionals familiar with the geologic and seismic setting
of the site. As a minimum, structure design should conform to Uniform Building Code (UBC)
requirements for Seismic Zone 4. Pertinent seismic design criteria as outlined in the 1997 UBC, is
summarized in Appendix C.
Caving did occur within each of our exploratory borings and the surface soils will be susceptible to
caving within deeper excavations. All excavations should be constructed in accordance with the normal
CalOSHA excavation criteria. On the basis of our observations of the materials encountered, we
anticipate that the subsoils will conform to those described by CalOSHA as Type C. Soil conditions
should be verified in the field by a "Competent person" employed by the Contractor.
The' SUrface soils encountered during our investigation were found to be non -expansive to moderately
expansive. Laboratory testing indicated an Expansion Index of 0, for the silty sands and 49 for the sandy
silts which correspond with the "very low" to "low" categories in accordance with UBC Standard 18-2. If
imported soils are to be used during grading, they should have an Expansion Index of less than 20. The
expansion potential of the site soils will change as a result of mixing that will occur during grading.
Expansion potential should be evaluated after grading.
Slodden Engineering
_J
May 8, 2000 -3- Project No. 544-0102
00-05-197
Tile following recommendations present more detailed design criteria, that have been developed on the
basis of our field and laboratory investigation.
Foundation Design: The results of our investigation indicate that either conventional shallow
continuous footings or isolated pad footings, that are supported upon properly compacted soils,
may be expected to provide satisfactory support for the proposed structures. Recompaction
ShOUld be performed as described in the Site Grading Section of this report.
Footings should extend at least 12 inches beneath lowest adjacent grade for single story
structures. Isolated square or rectangular footings at least 2 -feet square may be designed using an
allowable bearing value of 2000 pounds per square foot. Continuous footings at least 12 inches
wide may be designed using an allowable bearing value of 1800 pounds per square foot.
Allowable increases of 200 psf for each additional I -foot of width and 200 psf for each additional
6 -inches of depth may be utilized for larger footings. The maximum allowable bearing pressure
should be 3000 psf. The allowable bearing pressures are for dead and frequently applied live
loads and may be increased by 1/3) to resist wind, seismic or other transient loading
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Because of the hydroconsolidation potential Of tile Soils underlying, the site, care should be taken
to see that bearina soils are not allowed to become saturated frorn the ponding of rainwater or
irrigation. Drainage from the building areas should be rapid and complete.
1-1
Tile recornmendations made in the preceding paragraphs are based oil the assumption that all
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footings will be supported upon properly compacted engineered fill soils. All grading shall be
performed under the testing and inspection of the Soils Engineer or his representative. Prior to
the placement of concrete, we recommend that the footing excavations be inspected in order to
verify that they extend into compacted soil and are free of loose and disturbed materials.
Settlements: Settlements may result from the anticipated foundation loads. These estimated
ultimate settlements are calculated to be a maximum of 1 -inch when using the recommended
bearing values. As a practical matter, differential settlements between footings can be assumed as
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one-half of the total settlement.
Lateral Desicyn: Resistance to lateral loads can be provided by a combination of friction acting
at the base of the slabs or foundations and passive earth pressure along the sides of the
foundations. A coefficient of friction of 0.40 between soil and concrete may be used with dead
load forces only. A passive earth pressure of 250 pounds per square foot, per foot of depth, may
be used for the sides of footings, which are poured against properly compacted native soils.
Passive earth pressure should be ignored within the upper 1 -foot except where confined (such as
beneath a floor slab). When used in combination, either the passive resistance or the coefficient
of friction should be reduced by one-third.
Retaining Walls: Retaining walls may be required to accomplish tile proposed construction.
ive pressures may be
Canti er retaining walls may be designed using "active" pressures. Acti
estimated using an equivalent fluid weight of 35 pcf for native backfill soils with level free -
draining backfill conditions.
Slodden Engineering
May 8, 2000 -4- Project No. 544-01027
19
00-05-197
For walls that are restrained, "at rest" pressures should be utilized in design. At rest pressures
may be estimated using an equivalent fluid weight of 55 pcf for native backfill soils with level
free -draining backfill conditions.
Expansive Soils: Due to the prominence of non -expansive soils on'the site, special expansive
soil design criteria should not be necessary for the design of foundations and concrete slabs -on -
grade. Final design criteria should be established by the Structural Engineer.
Concrete Slabs -on -Grade: All surfaces to receive concrete slabs -on -grade should be underlaill
by recompacted soils as described in the Site Grading Section of this report. Where slabs are to
receive moisture sensitive floor coverings or where dampness of the floor slab is not desired, we
recommend the use of an appropriate vapor barrier. Vapor barriers should be protected by at least
two inches of sand in order to reduce the possibility of damage and to aid in obtaining uniform
concrete curing.
Reinforcement of slabs-on-crrade in order to resist expansive soil pressures may not be reqUired
however, reinforcement will have a beneficial effect in containincr cracking due to concrete
7 0
shrinkage. Temperature and shrinkage related cracking should be anticipated in all concrete
slabs -on -grade. Slab reinforcement and the spacing, of control joints should be determined by die
Structural Encrineer.
Soluble Sulfates: The soluble sulfate concentrations of the surface soils were determined to be
approximately 4,746 parts per million (ppm) which is considered corrosive with respect to
concrete. Soluble sulfate concentration will likely change as a result of the recommended site
grading. Soluble sulfate content should be determined after grading and appropriate concrete mix
designs should be selected in accordance with UBC Table 19-A-3.
Tentative Pavement Design: All paving should be underlain by a minimum compacted fill
thickness of 12 inches (excluding aggregate base). This may be performed as described in the
Site Grading Section of this report. R -Value testing was not performed. On this basis, a
pavement section of 3.0 inches of asphalt on 4.0 inches of base material should be applicable for
the preliminary design of the majority of the onsite pavement. The appropriate pavement sections
for off site improvements will be dependent upon traffic indices determined by the City of
La Quinta, California.
Aggregate base should conform to the requirements for Class 2 Aggregate base in Section 26 of
CalTrans Standard Specifications, January 1992. Asphaltic concrete should conform to Section
39 of the CalTrans Standard Specifications. The recommended sections should be provided with
a uniformly compacted subgrade and precise control of thickness and elevations durilicr
placement.
Pavement and slab designs are tentative and should be confirmed at the completion of site
grading when the subgrade soils are in-place. This will include sampling and testing of the actual
subgrade soils and an analysis based upon the specific traffic information
Slodden Engineering
May 8, 2000 -5- Project No. 544-0102
00-05-197
Shrinkage and Subsidence: Volumetric shrinkage of the material, which is excavated and
replaced as controlled compacted fill should be anticipated. We estimate that this shrinkage
could vary from 15 to 25 percent. Subsidence of the surfaces which are scarified and compacted
should be between 0.1 and 0.2 tenths of a foot. This will vary depending upon the type of
equipment used, the moisture content of the soil at the time of grading and the actual degree of
compaction attained.
These values for shrinkage and subsidence are exclusive of losses, which will occur due to the
stripping of the organic material from the site, the removal of deleterious materials and the
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removal of debris, and other subsurface obstructions.
General Site Grading: All grading should be performed in accordance with the grading
ordinance of the City of La Quinta, California. Tile followina recommendations have been
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developed on the basis of our field investigation and laboratory testing:
1. . Clearing arid Grubbing: Proper clearing of any existing vegetation and debris will be
very important. All surfaces to receive compacted fill should be cleared of roots,
vegetation, debris, and other unsuitable materials which should be removed frorn the site.
I
Solis that are disturbed due to the removal of the surface vegetation, previous
improvements or artificial fill material ShOUld be replaced as controlled compacted fill
under the direction of the Soils Engineer.
Preparation of Building Areas: Within the building areas, removal and recompaction
of the primary foundation bearing soils is recommended. As a minimum, removals
within the building areas should extend to a depth of at least 3 feet below existing grade
or 3 feet below the bottom of the footings, whichever is deeper. The exposed surface
should be scarified, moisture conditioned and compacted so that a minimum of 90%
relative compaction is attained. Once deleterious materials are removed, the native soils
and artificial fill materials may be placed as control,led compacted -fill. Overexcavation
should be observed by a representative of Sladden Engineering and compaction should be
verified by testing. Overexcavation should extend at least 5 feet laterally beyond the
footinas.
1.7
3. Preparation of Surfaces to Receive Compacted Fill: Other areas to receive compacted
fill should be brought to near optimum moisture content and compacted to a minimum of
90% relative compaction.
Placement of Compacted Fill: Fill materials consisting of on-site soils or approved
imported granular soils, should be spread in thin lifts, and compacted at near optimum
moisture content to a minimum of 90% relative cornpaction. Imported material shall
have an Expansion Index not exceeding 20. The contractor shall notify the Soils
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Engineer at least 48 hours in advance of importing soils in order to provide sufficient
tirne for the evaluation of proposed import materials.
The contractor shall be responsible for delivering material to the site, which complies
with the project specifications. Approval, by the Soils Engineer will be based upon
material delivered to tile site and not the preliminary evaluation of import sources.
Slodden ErtgIneering
May 8, 2000 -6- Project No. 544-0102
00-05-197
Our observations of the material encountered during our investigation indicate that
compaction will be most readily obtained by means of heavy rubber -wheeled equipment
and/or vibratory compactors. At the time of our investigation, the subsoils were found to
be quite dry. A more uniform moisture content should be attained during recompaction
and fill placement.
5. Preparation of Slab and Pavement Areas: All surfaces to receive asphalt concrete
pavement or concrete slabs -on -grade, should be underlain by a minimum compacted fill
thickness of 12 inches. This may be accomplished by a combination of scarification and
recompaction of the surface soils and placement of the fill material as controlled
compacted fill. Compaction of the slab and pavement areas should be to a minimum of
90 percent relative compaction.
6. Testing and Inspection: During grading tests and observations should be performed by
the Soils Enaineer or his representative in order to verify that the grading is being
performed in accordance with the project specifications. Field density testing shall be
performed in accordance with acceptable ASTM test methods. The minimum acceptable
degree of compaction should be 90 percent of the maximum dry density as obtained by
the ASTM D1557-91 test method. Where testing* indicates insufficient density,
additional cornpactive effbil shall be applied until retesting indicates satisfactory
compaction.
GENERAL
The fi.ndings and recommendations presented in this report are based upon an interpolation of the soil
conditions between the exploratory boring locations and extrapolation of these conditions throughout tile
proposed building area. Should conditions encountered during grading appear. different than those
indicated in this report, this office should be notified.
This report is considered to be applicable for use by Mr. Dale Frank and consultants for the specific site
and project described herein. The use of this report by other parties or for other projects is not authorized.
The recommendations of this report are contingent upon monitoring of the grading operations by a
representative of Sladden Engineering. All recommendations are considered to be tentative pending our
review of the grading operations and additional testing, if indicated. If others are employed to perform
any soil testing, this office should be notified prior to such testing in order to coordinate any required site
visits by our representative and to assure indemnification of Sladden Engineering.
Our investi(Yation was conducted prior to the completion of plans for the project. We recommend that a
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pre -job conference be held on the site prior to the initiation of site grading. The purpose of this meeting
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will be to assure a complete understanding of the recommendations presented in this report as they apply
to the actual grading performed.
0
Sladden Engineering
6upeoul6u3i ulappois
SIDO-1 S2UIJ08
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APPENDIX A
FIELDEXPLORATION
Fdr our field investigation, 8 exploratory borings were excavated on April 25, 2000, using a truck
mounted hollow stem auger rig (Mobile B53) in the approximate locations indicated on the site plan
included in this appendix. Continuous logs of the materials encountered were made on the site by a
representative of Sladden Engineering. Boring logs are included in this appendix.
Representative undisturbed samples were obtained within our borings by driving a thin-walled steel
penetration sampler (California split spoon sampler) or a Standard Penetration Test (SPT) sampler with a
140 pound hammer dropping approximately 30 inches (ASTM D1586). The number of blows required to
drive the samplers 18 inches was recorded (generally in 6 inch increments). BIOWCOUnts are indicated on
the boring logs.
The California samplers are 3.0 inches in diameter, carrying brass sample rings having inner diameters of
2.5 inches. The standard penetration samplers are 2.0 inches in diameter with an inner diameter of 1.5
inches. Undisturbed samples were removed from the sampler and placed in moisture sealed containers in
order to preserve the natural soil moisture content. Bulk samples were obtained frorn the excavation
spoils and samples were then transported to our laboratory for further observations and testing. Samples
were then transported to Our laboratory for further observations and testing.
Sladden Engineering
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Proposed Commercial Development
Highway 111 and Washington Street La Quinta, California
Date: 4-25-00 Boring
o. 1 Job No.: 544-0102
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DESCRIPTION >1
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Sandy Silt: Brown, clayey NM
7112/15
89
5.3
77
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Silty Sand: Brown, Sm
-Ihininterbedd OCI�Y—ers
94
1.5
09/10/20
fine grained
Sandy Silt: Brown, M1
96
1.0
10/20/22
very sandy
10/15/50
11
82
3.1
Sand: Brown, slightly silty, Sp/sm
20
15/50-6"
fine grained
---
0.5
...
X
Sand: Brown, fine SP
25
20/35/40
to medium grained
0.5
---
Total Depth 26.5'
Recovered Sample
No Bedrock
Disturbed Sample
No Groundwater
30
35
40
45
50
Note: The stratification lines
represent the approximate
boundaries between the soil types;
the transitions may be gradual.
Proposed Commercial Development
Highway 111 and Washington Street La Quinta, California
Date: 4-25-00 Boring
No. 2 Job No.: 544-0102
0
DESCRIPTION
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Sandy Silt: Brown, clayey Mil
5
Sandy Silt: Brown, NIL
2.6
---
V8/10/10
very sandy
5/10/10
Clayey Silt: Brown, 2.0
IVIL
slightly sandy
Sand: Brown, slightly silty, SP/Sm
fine grained 0.5
_1]10/10/20
[U1 Standard Penetration
Total Depth 16.5'
No Bedrock
Sample
No Groundwater
20
25
30
35
40
45 1
50
Note: The stratification lines
55
represent the approximate
boundaries between the soil types;
the transitions may be gradual.
Proposed Commercial Development
Highway 111 and Washington Street La Quinta, California
Date: 4-25-00 Boring
o. 3 Job No.: 544-0102
0
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Silty Sand: Brown, Sm
fine grained
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8/13/15
Sand: Brown, fine SP
101
1.5
---
-
to medium grained
a
10
Sand: Brown, slightly silty, SP/Sm
94
1.0
---
6/11/20
fine grained
15
10/20/20
0.5
X
20
10/20/25
Silty Sand: Brown, Sm
100
1.0
...
fine grained
25
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15/20/30
Sandy Silt: Brown, clayey ML
90
2.0
78
30
10/15/23
Sand: Brown, slightly silty, SP/Sm
---
1.0
...
fine grained
35
13/15/20
Sandy Silt: Brown,
2.6
---
very sandy
40
Sand: Brown, slightly silty, SP/Sm
T
5/15/2 0
fine grained
---
1.0
---
Total Depth 41.5'
Recovered Sample
No Bedrock
Disturbed Sample
No Groundwater
45
Standard Penetration
Sample
50
Note: The stratification Lines
55
represent the approximate
boundaries between the soil types;
the transitions may be gradual.
Proposed Commercial Development
Highway 111 and Washington Street La Quinta, California
Date: 4-25-00 Boring
o. 4 Job No.: 544-0102
0
DESCRIPTION
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6/10/11
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6/9/10
Sand: Brown, slightly silty, SP/SMI 0.5
fine grained
1115
8/10/15
ML 1.0
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Sandy Silt: Brown, clayey
2(
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Silty Sand: Brown, Sm
8/10/15
very sandy 0.5
Ju Standard Penetration
Total Depth 21.5'
No Bedrock
Sample
No Groundwater
25
30
35
40
4
50
Note: The stratification lines
55
represent the approximate
boundaries between the soi.1 types;
the transitions may be gradual.
Proposed Commercial Development
Highway 111 and Washington Street La Quinta, California
Date: 4-25-00 Boring
No. 5 Job No.: 544-0102
0
DESCRIPTION
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REMARKS
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0
0
0
0
0
Sandy Silt: Brown, clayey M,
5
8/12/19 1 Clayey Silt: Brown, JV[L
...
83
L5
I slightly sandy
10
8/10/18
84
1.0
---
15
10/15/20 Sand: Brown, sliglidy silty, SP/Sm
Unrecovered sample
fine grained
20
20/20/261
103
1.5
...
Sand: Brown, fine
25
10/20/30
to medium grained
...
0.5.
...
Total Depth 26.5'
Recovered Sample
No Bedrock
Disturbed Sample
No Groundwater
30
35
40
45
Note: The stratification lines
55
represent the approximate
boundaries between the soil types;
the transitions may be gradual.
Proposed Commercial Development
Highway 111 and Washington Street La Quinta, California
Date: 4-25-00 Boring
No. 6 Job No.: 544-0102
4-;
0
44
DESCRIPTION
co
Q
REMARKS
X
ca)
�Q
1
0
04 E
Cl)
0
0
U)
�D
0
0
-
Sandy Silt: Brown, clayey ML
5
5/8/10
Clayey Silt: Brown, ML
...
7.0
...
slightly sandy
10
6/8/11
Sandy Silt: Brown, clayey ML
1.0
15
Sand: Brown, slightly silty, SP/SMI:
7/10/10
fine grained
2.0
---
Total Depth 16.5'
-ation
Standard Penet.i�
No Bedrock
Sample
No Groundwater
20
25
30
35
40
45
50
Note: The stratification lines
55
represent the approximate
boundaries between the soil types;
the transitions may be gradual.
Proposed Commercial Development
Highway I I I and Washington Street La Quinta, California
Date: 4-25-00 Borina
No. 7 Job No.: 544-0102
0
DESCRIPTION
REMARKS
-0
Cn
0
4j
0
CD
P
co
0,
0
0
W
15
0
0
SandySiIE: Brown,
NIL
7/9/10
very sandy
91
4.2 1
Thin interbedded silt layers
5
6/10/12 i Clayey Silt: Brown,
ML
78
3.6
slightly sandy
10
91
1.0
M10/10/1-1:
15
Sand: Brown,
0.5
Fi'M10/12/20'SilEy
SM
96
fine grained
20
---
1.0
Total Depth 21.5'
Recovered Sample
i i No Bedrock
Disturbed Sample
No Groundwater
25
30
35
40
45
50
Note: The stratification lines
55
represent the approximate
boundaries between the soil types;
the transitions may be gradual.
Proposed Commercial Development
Highway 111 and Washington Street / La Quinta, Califo'rnia
Date: 4-25-00 Boring
No. 8 Job No.: 544-0102
0
44
—
DESCRIPTION
04
>1
>1
$4
0
>
Cz Cz
REMARKS
E-
0
0,
-0
0
�D "M)
�z
0
0
Sandy Silt: Brown, clayey
ML
5
2/4/'4
Sandy Silt: Brown,
NIL
---
15.6
---
very sandy
10
...
8/10/10 Sand: Brown, slightly silty, SP/Sm
---
2.6
fine grained
15
[Clayey Silt: Brown,
i
4/4/5 slightly sandy
29.0
Total Depth 16.5'
Standard Penetration
lu
No Bedrock
Sample
No Groundwater
20
26
30
35
40
45
50
Note: The stratification lines
5 -5)
represent the approximate
boundaries between the soil types;
the transitions may be gradual.
APPENDIX B
LABORATORY TESTING
Representative bulk and relatively undisturbed soil samples were obtained in the field and returned to our
laboratory for additional observations and testing. Laboratory testing was generally performed in two
phases. The first phase consisted of testing in order to determine the compaction of the existing natural
soil and the general engineering classifications of the soils underlying the site. Tills testing was
performed in order to estimate the engineering characteristics of the soil and to serve as a basis for
selecting samples for the second phase of testing. The second phase consisted of soil mechanics testing
This testing including consolidation, shear strength and expansion testing was performed in order to
provide a means of developing specific design recommendations based on the mechanical properties of
the soil.
CLASSIFICATION AND COMPACTION TESTING
Unit Weight and Moisture Content Determinations: Each undisturbed sample was weighed and
measured in order to determine its unit weight. A small portion of each sample was then Subjected to
testing in order to determine its moisture content. This was used in order to determine the dry density of
the soil in its natural condition. Tile results of this testing are shown on the Boring Loors.
Maximum Density -Optimum Moisture Determinations: Representative soil types were selected for
maximum density determinations. This testing was performed in accordance with the ASTM Standard
D1557-91, Test Method A. The results of this testing are presented graphically in this appendix. The
maximurn densities are compared to the field densities of the soil in order to deterlillne the existinga
relative compaction to the soil. Tills is shown oil tile Boring Logs, and is useful in estimacing the strength
and compressibility of the soil.
Classification Testing: Soil samples were selected for classification testing. This testing consists of
mechanical grain size analyses and Atterberg Limits determinations. These provide information for
developing classifications for the soil in accordance with the Unified Classification System. This
classification system categorizes the soil into groups having similar engineering characteristics. The
results of this testing are very useful in detecting variations in the soils and in selecting samples for
further testing.
SOIL MECHANIC'S TESTING
Direct Shear Testing: Two bulk samples were selected for Direct Shear Testing. This testing measures
the shear strength of the soil under various normal pressures and is used in developing parameters for
foundation design and lateral design. Testing was performed using recompacted test specimens, which
were saturated prior to testing.
., Testing was performed using a strain controlled test apparatus with
normal pressures rancring frorn 800 to 2300 pounds per square foot.
0 0
Expansion Testing: These bulk samples were selected for Expansion testing. Expansion testing was
performed in accordance with the UBC Standard 18-2. This testing consists of remolding 4 -Inch diameter
by 1 -inch thick test specimens to a moisture content and dry density corresponding to approximately 50
percent saturation. The samples are subjected to a surcharge of 144 pounds per square foot and allowed
to reach equilibrium. At that point the specimens are inundated with distilled water. The linear
expansion is then measured until complete.
Sladden EngIneering
117
115
>1 114
113
112
Job No.: 544-0102
12 13 14 15 16 17 18
Moisture Content
METHOD OF COMPACTION
ASTM D- 1557-91, METHOD A: OR C
BORING MAXIMUM UNIT WEIGHT
I @ 0'- 5' 116
OPTIMUM MOISTURE CONTENT
15.0
MAXIMUM DENSITY -OPTIMUM MOISTURE CURVE
DIRECT SHEAR TEST
1.8
1.6
1.4
1.2
1.0
00�
.8
.4
.2
0
0 .2 .4 .6 .8 1.0 1.2 1.4 1.6 1.8
0 = 280
c = 250psf
where 0 = Shear Angle
C = Cohesion Boring I @ 0 - 5'
Proposed Commercial Development
Highway I 11 and Washington Street
La Quinta, California
Sladden Engineering
DATE: 5-10-00 JOB NO.: 544-0102
0.0
.01
0.000
z
z z z=F- z
Z z
Pressure in KIPS per Square Foot
0.720 2.880 11.520
z
c
ffict—nFAcEdi
VEI-er:-:
z 7 z z
Z Z
.02
Z: =::t:
Z
7. z
I
z
.03
z 7 z
z z
.04
7
.05
i
z
+
.06
m
:,---ZZ"
-- ----- - --
Ic
Z Z
.07
.08
.09
Z
z
Z
0.1
c
Z
z
=:q-- z
z
.12
=T—
z z
.13
z
Z
-- - ----
z
z
Highway 111 and Washington Street
Consolidation Diagram
Bor in.- I @ 5'
SLADDEN ENGINEERING
Date: 5/10/00 1 Job No.: 544-0102
Pressure in KIPS per Square Foot
0.000
0.720 2.880
11.520
r-
0.0
----------
A--9
':E- z
.01
.02
.03
x
lttuiid
z z
.04
z z
.05
z
z
L
.06
0
z
z
m:
r-
rz
cz
z
-
7-
0
.07
z
cn
r-
o
7 — -
- z zzz:F- z
- — =
z Z.
.08
.09
- — - ----------
0.1
=:zp
.12
.13
7- C
Highway 111 and Washington Street
Consolidation Diagram
Boring I @ 10'
SLADDEN ENGINEERING
Date: 5/10/00 1 Job No.: 544-0102
Pressure in KIPS per Square Foot
0.000
0.575 2.300
9.200
z
z
0.0
z z
:t-- z
z
.02
z
z z
z
1 E
z
.04
Z
+
z
Z Z I
z c
.06
Z
t
z
z
z
.08
z z z
z z
c
cn
.10
Z
7-
:-Z L 7-'
C z
-L
7- E�E\
Z
— z
z
z
z
12
z
0
z 1
— - — - ----------- -
-
0
cn
C:
o
.14
–
Z z
7
mboiunT=�t
z
7z 7.
z
z
.16'
Z z
z
Z
z z
Z
Z
Z z
.20
Z
z Z z z z
7z Z.
7-
.22
z
z :i--
z
z
z
7Z
.24
z
z
==Z�
z
.26
Z
c
z z I
z
z
H Highway 111 and Washington Street
ig hway
Consolidation Diagram
Bo'ring 7 @ 5'
EDate:5/10/00
LADDEN ENGINEERING
S L
I Job No.: 544 -0102
Pressure in KIPS per Square Foot
0.000
.575
2.300
9.200
Z
z
z T=
0.0
z
z
E ffe c -t -a A d d='—' z
.9 -
— z
Ea- e r-_ = z
z
z
.01
z
z z
.02
Z'
7- z z
Z
z
.03
Z
z
z
z
z z
C
.04
Z
z
7-
Z 7 -
CL
cn
.05
z
T
77�
z
z
:ERe
z :SZ-_- z
r z
Z
.06
z
z
cz
Z,- 7
z
0
.0
z....
.. =Z :7 Z'
7 z
z
z
0
z
z z
.08
z
z
7z
7-
.09
---
Z z
Z
Z
z
z z
0.1
=z:L-
z
z c
:-7
-Z
z
z
z
4--
z
7 z
.12
z c
.13
z
z
Highway 111 and Washington Stree
Consolidation Diagram
Boring 7 @ 10'
SLADDEN ENGINEERING
Date: 5/10/00 1 Job No.: 544-0102
ANAHEIM TEST LABORATORY
3008 S. ORANGE AVENUE
SANTA ANA, CALIFORNIA 92707
PHONE (714) 549-7267
TO: SLADDEN ENGINEERING:
6782 STANTON AVE. S&ITE E
BUENA PARK, CA. 9062 . 1 DATE: 4/28/00
P.O. No. VERBAL
N
Shipper No.
ATTN: BRETT ANDERSON
Lab. No. B 6 3 9 5
Specification:
Material: SOIL
PROJECT: # 544-0102
BULK H-1 @ 0-5'
:OnM #2
ANALYTICAL REPORT
SOLUBLE SULFATES
per CA. 417
4,746 ppm
4�.RE�SPECTf ULLY UBMITTE
POPPY Alkq Chief Chcmi!
APPENDIX C
1997 UBC Seismic Desl,crri Criteria
Slodden Engineering
1997 UNIFORM BUILDING CODE SEISMIC DESIGN INFORMATION
The International Conference of Building Officials 1997 Uniform Building Code contains
substantial revisions and additions to the earthquake engineering section in Chapter 16. New
concepts contained in the updated code that will likely be relevant to construction of the proposed
structures are surnmariz'ed below.
Ground shaking is expected to be the primary hazard most likely to affect the site, based upon
proximity to significant faults capable of generating large earthquakes. Major fault zones
considered to be most likely to create strong arround shaking at the site are listed below.
0
Fault Zone
Approximate Distance
From Site
Fault Type
(1997 UBC)
San Andreas*
9 km
A
San Jacinto
35 km
A
Based on our field observations and understanding of local geologic conditions,- the soil profile
0 0 0
type judged applicable to this site 'S SD, generally described as stiff or dense soil. The site Is
0 1 tD
located within UBC Seismic Zone 4. The following table presents additional coefficients and
factors relevant to seismic mitigation for new construction upon adoption of the 1997 code.
Slociden Engineering
Near -Source
Near -Source
Seismic
Seismic
Seismic
Acceleration
Velocity
Coefficient
Coefficient
Source
Factor, Na
Factor, Nv
Ca
Cv
San Andreas
1.1
1.3
0.44 Na
0:64 N,
San Jac�irito
1.0
1.0
0.44 N�
0.64 N,
Slociden Engineering