HomeMy WebLinkAboutCDP 13-25; GAITAUD RESIDENCE; GEOTECHNICAL INVESTIGATION; 2013-05-09CD I' I 3
San Diego 6280 Riverdale Street
SOUTHERN CALIFORNIA 619.280.4321 San Diego, CA 92120
SOIL &rEST1NG,INc. Indio 83:74o Citrus Avenue
- 760 775 5983 Suite G
A California Certified Small Business Enterprise ISBE) Indio, CA 92201-3438
Riverside 1130 Palmyrita Avenue
951.965.8711 Suite 330-A
Riverside, CA 92507
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877.215.4321 www.scst.com
GEOTECHNICAL INVESTIGATION
SINGLE-FAMILY RESIDENCE
4419 PARK DRIVE
CARLSBAD, CALIFORNIA
PREPARED FOR:
MR. PHIL GAITAUD
GAITAUD CONSTRUCTION
POST OFFICE BOX 28696
SAN DIEGO, CALIFORNIA 92198
PREPARED BY:
SOUTHERN CALIFORNIA SOIL & TESTING, INC.
6280 RIVERDALE STREET
SAN DIEGO, CALIFORNIA 92120
Providing Professional Engineering Services Since 1959
San Diego 6280 Riverdale Street
619.280.4321 San Diego, CA 92120
Indio 83.740 Citrus Avenue
760.775.5983 Suite G
Indio, CA 92201-3438
Riverside 1130 Palmynta Avenue
951.965.8711 Suite 330-A
Riverside, CA 92507
Toll Free
877.215.4321 www.sest.com
cc..,. SOUTHERN CALIFORNIA
(J SOIL &TESTINGII NC.
A California Certified Small Business Enterprise (SSE;
May 9, 2013
Mr. Phil Gaitaud
Gaitaud Construction
Post Office Box 28696
San Diego, California 92198
Subject: GEOTECHNICAL INVESTIGATION
SINGLE-FAMILY RESIDENCE
4419 PARK DRIVE
CARLSBAD, CALIFORNIA
Dear Mr. Gaitaud:
SCS&T No. 1311056
Report No. 2
This letter transmits Southern California Soil & Testing Inc.'s (SCS&T) report describing the
geotechnical investigation performed for the proposed project located at 4419 Park Drive in the
City of Carlsbad, California.
This investigation was conducted in general conformance with the scope of work presented in
SCS&T's proposal dated April 12, 2013. If you have any questions concerning this report, or
need additional information, please call us at (619) 280-4321.
Respectfully Submitted,
SOUTHERN CALIFORNL W TESTING, INC.
No 2591 7 v'
XPfl3
D 65 C ERING I-i'
,oFESS,Q 4,4
rn UJ NO. 2762 Jm
EXP. 09-30-14 J
OF
Andrew K. Neuhaus, (5 itain, GE 252
Senior Geologist Vice President, Princi nical Engineer
AKN:GBF:aw
(1) Addressee via e-mail at philgaitaud@hotmail.com
TABLE OF CONTENTS
SECTION PAGE
EXECUTIVE SUMMARY .........................................................................................................................1
INTRODUCTION .........................................................................................................................
.
...... 1
1.1 GENERAL .......................................................................................................................................I
1.2 SCOPE OF WORK.............................................................................................................................1
1.2.1 Field Exploration..................................................................................................................1
1.2.2 Laboratoiy Testing................................................................................................................1
1.2.3 Analysis and Report..............................................................................................................1
SITE AND SUBSURFACE CONDITIONS .....................................................................................2
2.1 SITE DESCRIPTION..........................................................................................................................2
2.2 SUBSURFACE CONDITIONS.............................................................................................................2
2.3 LIQUEFACTION ............................................................................................................................... 2
2.4 SEISMIC DESIGN PARAMETERS ......................................................................................................2
CONCLUSIONS .................................................................................................................................
RECOMMENDATIONS....................................................................................................................3
4.1 SITE PREPARATION AND GRADING.................................................................................................
4.1.1 Site Preparation - Shallow Foundation System....................................................................3
4.1.2 Site Preparation - Deep Foundation System ........................................................................ 4
4.1.3 Earthwork.............................................................................................................................4
4.1.4 Site Excavation Characteristics............................................................................................4
4.1.5 Expansive Material ............................................................. . ................................................. 4
4.1.6 Imported Soil.........................................................................................................................4
4.1.7 Suiface Drainage..................................................................................................................5
4.1.8 Grading Plan Review............................................................................................................5
4.2 FOUNDATIONS ...............................................................................................................................5
4.2.1 Rigid Foundation System ...................................................................................................... 5
4.2.2 Deep Foundations.................................................................................................................6
TABLE1......................................................................................................................................................6
4.2.3 Settlement Characteristics....................................................................................................6
4.2.4 Foundation Plan Review.......................................................................................................7
4.2.5 Foundation Excavation Observations...................................................................................7
4.3 SLABS-ON-GRADE ..........................................................................................................................
4.3.1 Interior Concrete Slabs-on-Grade ........................................................................................ 7
4.3.2 Exterior Slabs-on-Grade ....................................................................................................... 7
GEOTECHNICAL ENGINEERING DURING CONSTRUCTION.............................................8
CLOSURE ...........................................................................................................................................8
ATTACHMENTS
FIGURES
Figure 1 - Site Vicinity Map
Figure 2 - Subsurface Investigation Map
APPENDICES
Appendix I - Logs of Exploratory Test Pits
Appendix II - Laboratory Testing
EXECUTIVE SUMMARY
This report presents the results of the geotechnical investigation Southern California Soil and
Testing, Inc. (SCS&T), performed for the project located at 4419 Park Drive in the City of
Carlsbad, California. We understand that the project will consist of the design and construction of
a single-family residence. The purpose of our work is to provide conclusions and
recommendations regarding the geotechnical aspects of the project.
Two exploratory borings were drilled with a truck-mounted drill rig. The borings extended to
depths of between about 20 feet and 60 feet below the existing ground surface. An SCS&T
geologist logged the exploratory borings and collected soil samples for laboratory testing.
Selected samples from the borings were tested to evaluate pertinent classification and
engineering properties to assist in the development of geotechnical conclusions and
recommendations.
Materials encountered in the borings consist of alluvial flood-plain deposits and Santiago
Formation. The alluvial flood-plain deposits are comprised of very loose to dense clayey sand,
soft to very stiff sandy clay and medium dense to dense poorly graded sand. The Santiago
Formation is comprised of very stiff to hard sandy claystone and dense to very dense clayey
sandstone. Groundwater was encountered in exploratory boring B-I at a depth of about 20 feet
below the existing ground surface.
The main geotechnical considerations affecting the subject project is the presence of potentially
compressible alluvial flood-plain deposits. The planned residence can be supported on a rigid
foundation system with bottom levels in compacted fill or deep foundations. The grading and
foundation recommendations herein may need to be updated once final grading and foundation
plans are developed.
1. INTRODUCTION
1.1 GENERAL
This report presents the results of the geotechnical investigation Southern California Soil and
Testing, Inc. (SCS&T), performed for the project located at 4419 Park Drive in the City of
Carlsbad, California. We understand that the project will consist of the design and construction of
a single-family residence. The purpose of our work is to provide conclusions and
recommendations regarding the geotechnical aspects of the project. Figure 1 presents a site
vicinity map.
1.2 SCOPE OF WORK
1.2.1 Field Exploration
Two exploratory borings were drilled with a truck-mounted drill rig at the approximate locations
shown on Figure 2. An SCS&T geologist logged exploratory borings and collected soil
samples for laboratory testing. The borings extended to depths of between about 20 feet and
60 feet below the existing ground surface. Selected samples from the borings were tested to
evaluate pertinent classification and engineering properties to assist in the development of
geotechnical conclusions and recommendations. The logs of the exploratory borings are in
Appendix I. Soils are classified according to the Unified Soil Classification System illustrated
on Figure I-i.
1.2.2 Laboratory Testing
The laboratory program consisted of tests for:
Grain size distribution;
Expansion potential;
Consolidation; and
Direct shear.
The results of the laboratory tests, and brief explanations of test procedures, are in Appendix
II.
1.2.3 Analysis and Report
The results of the field and laboratory tests were evaluated to develop conclusions and
recommendations regarding:
Subsurface conditions beneath the site;
Site preparation recommendations;
Criteria for seismic design in accordance with California Building Code procedures;
Appropriate alternatives for foundation support along with geotechnical engineering criteria
for design of the foundations;
Resistance to lateral loads;
Estimated foundation settlements;
Support for concrete slabs-on-grade.
s1T
Gaitaud Construction May 9, 2013
4419 Park Drive Residential Lot SCS& T No. 1311056-02
Carlsbad, California Page 2
2. SITE AND SUBSURFACE CONDITIONS
2.1 SITE DESCRIPTION
The subject site is an undeveloped lot located at 4419 Park Drive in the City of Carlsbad,
California. A developed residential property bounds the site on the north, Park Drive bounds the
site on the east, a 3-foot retaining wall and unpaved driveway bound the site on the south, and
undeveloped land bounds the site on the west. Slopes ascend from the north and west sides of
the lot at an inclination of about 2:1 (horizontal:vertical). Vegetation consists of typical native
grasses, shrubs and trees.
2.2 SUBSURFACE CONDITIONS
Materials encountered in the borings consist of alluvial flood-plain deposits and Santiago
Formation. The alluvial flood-plain deposits are comprised of very loose to dense clayey sand,
soft to very stiff sandy clay and medium dense to dense poorly graded sand. The Santiago
Formation is comprised of very stiff to hard sandy claystone and dense to very dense clayey
sandstone. Groundwater was encountered in exploratory boring B-i at a depth of about 20 feet
below the existing ground surface.
Groundwater levels can fluctuate seasonally, and can rise significantly following periods of
precipitation. In addition, groundwater can become perched as a result of rainfall and irrigation.
2.3 LIQUEFACTION
Liquefaction occurs when loose, saturated, generally fine sands are subject to strong ground
shaking. The soils lose shear strength and become liquid, resulting in large total and differential
ground surface settlements as well as possible lateral spreading during an earthquake. Based on
our analysis the site could experience about 1 inch of total settlement from liquefaction during a
seismic event. Differential settlement can be expected to be about /2 inch.
2.4 SEISMIC DESIGN PARAMETERS
A geologic hazard likely to affect the project is groundshaking as a result of movement along an
active fault zone in the vicinity of the subject site. The site coefficients and adjusted maximum
considered earthquake spectral response acceleration parameters in accordance with the 2010
California Building Code based on the 2009 International Building Code are presented below:
Gaitaud Construction May 9, 2013
4419 Park Drive Residential Lot SCS&T No. 1311056-02
Carlsbad, California Page 3
Site Coordinates: Latitude 33.1480
Longitude -117.3260
Site Class: D
Site Coefficient Fa = 1.000
Site Coefficient F = 1.522
Spectral Response Acceleration at Short Periods S5 = 1.270
Spectral Response Acceleration at 1-Second Period S1 = 0.478
SMSFaSs = 1.270
SDS2/3* SMs0846
3. CONCLUSIONS
The main geotechnical considerations affecting the subject project is the presence of potentially
compressible alluvial flood-plain deposits. The planned residence can be supported on a rigid
foundation system with bottom levels in compacted fill or deep foundations. The grading and
foundation recommendations herein may need to be updated once final grading and foundation
plans are developed.
4. RECOMMENDATIONS
4.1 SITE PREPARATION AND GRADING
4.1.1 Site Preparation - Shallow Foundation System
Site preparation should begin with the removal of the existing improvements, vegetation and
debris in the areas to receive new structures. The existing fill, if any, should be excavated in
its entirety. The existing alluvial flood-plain deposits should be excavated to a depth of 5 feet
below the planned footing bottom levels beneath the structure, and 2 feet below the planned
subgrade elevation beneath the hardscape improvements. Excavations up to about 7 feet
deep should be expected. Horizontally, the excavation should extend at least 5 feet outside
perimeter footing lines or planned hardscape improvements or up to existing improvements,
whichever is less. The bottom of the excavation should be compacted to at least 95% relative
compaction. An SCS&T representative should observe conditions exposed in the bottom of
the excavation to determine if additional excavation is required.
A reinforcing fabric such as Mlrafi® HP570 or equivalent should be placed on the surface
exposed at the bottom of the excavation. It is expected the excavated material can be
replaced as compacted fill. The planned structure can be supported on a rigid foundation
system with bottom levels in compacted fill.
SIT,
Gaitaud Construction May 9, 2013
4419 Park Drive Residential Lot SCS&T No. 1311056-02
Carlsbad, California Page 4
4.1.2 Site Preparation - Deep Foundation System
Site preparation should begin with the removal of the existing improvements, vegetation and
debris in the areas to receive new structures. The existing fill should be excavated in its
entirety. The alluvial flood-plain deposits should be excavated to a depth of 2 feet below the
existing or final pad grade elevation, whichever is more. The upper 2 feet of soil below the
planned subgrade elevation beneath the hardscape improvements should be excavated.
Horizontally, the excavation should extend at least 5 feet outside perimeter footing lines or
planned hardscape improvements or up to existing improvements, whichever is less. The
bottom of the excavation should be compacted to at least 95% relative compaction.
An SCS&T representative should observe conditions exposed in the bottom of the excavation
to determine if additional excavation is required.
4.1.3 Earthwork
Excavated materials, except for soil containing roots and organic debris, can be used as
compacted fill. Fill should be placed in 6- to 8-inch thick loose lifts, moisture conditioned to
near optimum moisture content, and compacted to at least 90% relative compaction. The
maximum dry density and optimum moisture content for the evaluation of relative compaction
should be determined in accordance with ASTM D 1557.
Utility trench backfill within 3 feet of the structure and beneath pavements and hardscape
should be compacted to a minimum of 90% relative compaction. The upper 12 inches of
subgrade beneath slabs and paved areas should be compacted to at least 95% relative
compaction.
4.1.4 Site Excavation Characteristics
Conventional heavy equipment in good working order is expected to be able to excavate the
alluvial flood-plain deposits on-site. Gravel and cobbles should be anticipated within alluvial
flood-plain deposits. Contract documents should specify that the contractor mobilize
equipment capable of excavating and compacting materials with gravel, and cobbles.
4.1.5 Expansive Material
The existing materials on-site tested have a very low expansion potential. The foundation
recommendations presented in this report reflect a very low expansion potential.
4.1.6 Imported Soil
Imported fill should consist of predominately granular soil free of organic material and rocks
greater than 2 inches in maximum dimension. Imported soil should have an Expansion Index
sIrP
Gaitaud Construction May 9, 2013 4419 Park Drive Residential Lot SCS&T No. 1311056-02
Carlsbad, California Page 5
of 20 or less and should be inspected and, if appropriate, tested by SCS&T prior to transport
to the site.
4.1.7 Surface Drainage
Final surface grades around the building should be designed to collect and direct surface
water away from the structure and toward appropriate drainage facilities. The ground around
the structures should be graded so that surface water flows rapidly away from the structure
without pondirig. In general, we recommend that the ground adjacent to the structure slope
away at a gradient of at least 2%. Densely vegetated areas where runoff can be impaired
should have a minimum gradient of at least 5% within the first 5 feet from the structure. Roof
gutters with downspouts that discharge directly into a closed drainage system are
recommended on structures.
Drainage patterns established at the time of fine grading should be maintained throughout the
life of the proposed structures. Site irrigation should be limited to the minimum necessary to
sustain landscape growth. Should excessive irrigation, impaired drainage, or unusually high
rainfall occur, saturated zones of perched groundwater can develop.
4.1.8 Grading Plan Review
The grading plans should be submitted to SCS&T for review to ascertain whether the intent of
the recommendations contained in this report have been implemented, and that no revised
recommendations a, e necessary due to changes in the development scheme.
4.2 FOUNDATIONS
4.2.1 Rigid Foundation System
The planned building can be supported on a rigid raft or a mat foundation system. The mat
should have a bottom level at least 18 inches below the lowest adjacent finish pad grade. A
modulus of subgrade reaction, k of 50 pounds per cubic inch (pci) is considered appropriate
for the analysis of immediate settlement under raft foundation supported in compacted fill.
Additionally, a bearing capacity of 2,000 pounds per square foot (psf) can be used. This value
can be increased by % when considering the total of all loads, including wind or seismic
forces. Footings located adjacent or within slopes should be extended to a depth such that a
minimum horizontal distance of 7 feet exists between the bottom of the footing and the face of
the slope.
Lateral loads will be resisted by friction between the bottoms of footings and passive pressure
on the faces of footings and other structural elements below grade. The allowable coefficient
of friction of 0.30 can be used. Passive pressure can be computed using a lateral pressure
value of 300 psf per foot of depth below the ground surface. This value can be increadby
Gaitaud Construction May 9, 2013
4419 Park Drive Residential Lot SCS&T No. 1311056-02 Carlsbad, California Page 6
1/3 when considering the total of all loads, including wind or seismic forces. The upper 1 foot of
soil should not be relied on for passive support unless the ground is covered with pavements
or slabs.
4.2.2 Deep Foundations
Deep foundations consisting of drilled, cast-in-place concrete piers can be used to support the
residence. The axial capacity for 24-inch, 30-inch and 36-inch diameter piers was determined
using the computer program AllPile®. For our analyses, we assumed support would be
obtained from friction in the alluvial flood-plain deposits and/or Santiago Formation.
Recommended pier capacities are presented below in Table 1.
TABLE I
Vertical Capacity of Cast-In-Place Piers
(kips)
Depth Below Grade
Beam, Feet
Pier Diameter (inches)
24 30 36
20 20 25 40
30 50 65 80
40 90 115 130
Lateral loads will be resisted by passive pressure on the drilled piers. Passive pressure can
be computed using a lateral pressure value of 300 psf per foot of depth below the ground
surface acting on twice the pier diameter. The fill should not be relied on for passive support.
Groundwater seepage should be anticipated. It is anticipated that drilling fluid or casing can
be used to maintain an open hole. Cobble layers should be anticipated within the alluvial
flood-plain deposits. Well cemented zones should be anticipated within the Santiago
Formation. Contract documents should specify that the contractor mobilize equipment
capable of penetrating dense material required, to reduce the potential that claims for delays
or extra work will arise.
4.2.3 Settlement Characteristics
Total footing settlements are estimated to be less than 1 inch. Differential settlements
between adjacent footings, and between the middle and ends of continuous footings, are
estimated to be less than 1/2 inch. Settlements should occur rapidly, and should be completed
shortly after structural loads are applied.
Gaitaud Construction May 9, 2013
4419 Park Drive Residential Lot SCS&T No. 1311056-02
Carlsbad, California Page 7
4.2.4 Foundation Plan Review
The foundation plans should be submitted to SCS&T for review to ascertain that the intent of
the recommendations in this report has been implemented and that revised recommendations
are not necessary as a result of changes after this report was completed.
4.2.5 Foundation Excavation Observations
It is recommended that the foundation excavations be approved by a representative from
SCS&T prior to forming or placing reinforcing steel.
4.3 SLABS-ON-GRADE
4.3.1 Interior Concrete Slabs-on-Grade
The project structural engineer should design the concrete slabs-on-grade as heavily
reinforced slabs.
Slabs-on-grade should be underlain by a 4-inch thick blanket of clean, poorly graded, coarse
sand or crushed rock. A moisture vapor retarder/barrier should be placed beneath slabs
where floor coverings will be installed. Typically, plastic is used as a vapor retardant. If plastic
is used, a minimum lO-mil is recommended. The plastic should comply with ASTM E 1745.
Plastic installation should comply with ASTM E 1643.
Current construction practice typically includes placement of a two-inch thick sand cushion
between the bottom of the concrete slab and the moisture vapor retarder/barrier. This cushion
can provide some protection to the vapor retarder/barrier during construction, and may assist
in reducing the potential for edge curling in the slab during curing. However, the sand layer
also provides a source of moisture vapor to the underside of the slab that can increase the
time required to reduce moisture vapor emissions to limits acceptable for the type of floor
covering placed on top of the slab. The floor covering manufacturer should be contacted to
determine the volume of moisture vapor allowable and any treatment needed to reduce
moisture vapor emissions to acceptable limits for the particular type of floor covering installed.
4.3.2 Exterior Slabs-on-Grade
The upper 2 feet of soil below exterior concrete slabs-on-grade should have an Expansion
Index of 20 or less. Exterior concrete slabs-on-grade should have a minimum thickness of 4
inches: reinforced with at least No. 3 bars at 18 inches on center each way. Slabs should be
provided with weakened plane joints. Joints should be placed in accordance with the
American Concrete Institute Guidelines. The landscape architect should be consulted in
selecting the final joint patterns.
Gaitaud Construction May 9, 2013
4419 Park Drive Residential Lot SCS&T No. 1311056-02
Carlsbad, California Page 8
A 1-inch maximum size aggregate mix is recommended for concrete for exterior slabs. A
water/cement ratio of less than 0.45 also is recommended, to decrease the potential for
shrinkage cracks. The corrosion potential of on-site soils with respect to reinforced concrete
will need to be taken into account in concrete mix design. Coarse and fine aggregate in
concrete should conform to the "Greenbook" Standard Specifications for Public Works
Construction.
5. GEOTECHNICAL ENGINEERING DURING CONSTRUCTION
The geotechnical engineer should review project plans and specifications prior to bidding and
construction to check that the intent of the recommendations in this report has been incorporated.
Observations and tests should be performed during construction. If the conditions encountered
during construction differ from those anticipated based on the subsui1ace exploration program,
the presence of the geotechnical engineer during construction will enable an evaluation of the
exposed conditions and modifications of the recommendations in this report or development of
additional recommendations in a timely manner.
6. CLOSURE
SCS&T should be advised of any changes in the project scope so that the recommendations
contained in this report can be evaluated with respect to the revised plans. Changes in
recommendations will be verified in writing. The findings in this report are valid as of the date of
this report. Changes in the condition of the site can, however, occur with the passage of time,
whether they are due to natural processes or work on this or adjacent areas. In addition, changes
in the standards of practice and government regulations can occur. Thus, the findings in this
report may be invalidated wholly or in part by changes beyond our control. This report should not
be relied upon after a period of two years without a review by us verifying the suitability of the
conclusions and recommendations to site conditions at that time.
In the performance of our professional services, we comply with that level of care and skill
ordinarily exercised by members of our profession currently practicing under similar conditions
and in the same locality. The client recognizes that subsurface conditions may vary from those
encountered at the boring locations, and that our data, interpretations, and recommendations are
based solely on the information obtained by us. We will be responsible for those data,
interpretations, and recommendations, but shall not be responsible for interpretations by others of
the information developed. Our services consist of professional consultation and observation
only, and no warranty of any kind whatsoever, express or implied, is made or intended in
connection with the work performed or to be performed by us, or by our proposal for consulting or
other services, or by our furnishing of oral or written reports or findings.
APPENDIX I
APPENDIX I
FIELD INVESTIGATION
Two exploratory borings were drilled with a truck-mounted drill rig at the locations indicated on
Figure 2 on April 22, 2013. The fieldwork was performed under the observation of an SCS&T
geologist who also logged borings and test pits and obtained samples of the materials
encountered. Relatively undisturbed samples were obtained with a 2.5-inch inner diameter
sampler driven with a 140-pound weight falling 30 inches. Disturbed samples were obtained from
drill cuttings and during Standard Penetration Testing. Standard Penetration Tests were
performed by driving a 1.4-inch inner diameter sampler with a 140-pound weight falling 30 inches.
The number of blows required to drive the sampler the final 12 inches of an 18-inch drive are
noted on the borings logs as "Penetration (blows/ft. of drive)."
Soils are classified in accordance with the Unified Soil Classification System illustrated on Figure
I-i. The boring and test pit logs are presented on Figures 1-2 through 1-5.
APPENDIX II
APPENDIX II
LABORATORY TESTING
SUMMARY
Laboratory tests were performed to provide geotechnical parameters for engineering analyses.
The following tests were conducted:
CLASSIFICATION: Field classifications were verified in the laboratory by visual
examination. The final soil classifications are in accordance with the Unified Soil
Classification System.
GRAIN SIZE DISTRIBUTION: One grain size distribution was determined for one
sample in accordance with ASTM D 422. The results of the test are presented on Figure
EXPANSION INDEX TEST: An expansion index test was performed in accordance with
ASTM D 4289. The result of this test is presented on Figure 11-2.
CONSOLIDATION: A one-dimensional consolidation test was performed on two
relatively undisturbed samples in general accordance with ASTM D 2435. Results are
shown on Figures 11-3 through 11-4.
DIRECT SHEAR: A direct shear test was performed in accordance with ASTM D 3080.
The shear stress was applied at a constant rate of strain of approximately 0.003 inch per
minute. The results are presented on Figures 11-5 through 11-6.
Soil samples not tested are now stored in our laboratory for future reference and analysis, if
needed. Unless notified to the contrary, all samples will be disposed of 30 days from the date of
this report.
SUBSURFACE EXPLORATION LEGEND
UNIFIED SOIL CLASSIFICATION CHART
SOIL DESCRIPTION GROUP TYPICAL NAMES SYMBOL
COARSE GRAINED, more than 50% of material is larger than No. 200 sieve size.
GRAVELS CLEAN GRAVELS GW Well graded gravels, gravel-sand mixtures, little or no fines More than half of
coarse fraction is GP Poorly graded gravels, gravel sand mixtures, little or no fines. larger than No.4
sieve size but GRAVELS WITH FINES GM Silty gravels, poorly graded gravel-sand-silt mixtures. smaller than 3". (Appreciable amount of
fines) GC Clayey gravels, poorly graded gravel-sand, clay mixtures.
SANDS CLEAN SANDS SW Well graded sand, gravelly sands, little or no fines. More than half of
coarse fraction is SF Poorly graded sands, gravelly sands, little or no fines. smaller than No.
4 sieve size. SM Silty sands, poorly graded sand and silty mixtures.
SC Clayey sands, poorly graded sand and clay mixtures.
FINE GRAINED, more than 50% of material is smaller than No. 200 sieve size.
SILTS AND CLAYS ML Inorganic silts and very fine sands, rock flour, sandy silt or clayey-silt-
(Liquid Limit less sand mixtures with slight plasticity.
than 50) CL Inorganic clays of low to medium plasticity, gravelly clays, sandy clays,
silty clays, lean clays.
OL Organic silts and organic silty clays or low plasticity.
SILTS AND CLAYS MH Inorganic silts, micaceous or diatomaceous fine sandy or silty soils,
(Liquid Limit elastic silts.
greater than 50) CH Inorganic clays of high plasticity, fat clays.
OH Organic clays of medium to high plasticity.
HIGHLY ORGANIC SOILS PT Peat and other highly organic soils.
FIELD SAMPLE SYMBOLS LABORATORY TEST SYMBOLS
- Bulk Sample AL - Atterberg Limits
CAL - Modified California penetration test sampler CON - Consolidation
CK - undisturbed chunk sample COR - Corrosivity Test
MS - Maximum Size of Particle - Sulfate
- Chloride
- Water seepage at time of excavation or as indicated
- pH and Resistivity
SPT - Standard penetration test sampler DS - Direct Shear
ST - Shelby Tube El - Expansion Index
- Water level at time of excavation or as indicated MAX - Maximum Density
RV -R Value
SA - Sieve Analysis
UC - unconfined Compression
4419 PARK DRIVE RESIDENTIAL LOT C SOUTHERN CALIFORNIA
lJob
By:AKN bate: 5/9/2013 ST SOIL& TESTING, INC.
Number 1311056-2 IFigure: I-i
LOG OF EXPLORATORY BORING NUMBER B-I
Date Excavated: 4/22/2013 Logged by: AKN
Equipment: Hollow Stem Auger Project Manager: GBF
Surface Elevation (if): N/A Depth to Water (if): 20
SAMPLES U)
- C.) C/) W
O- .
10 U) m w
SUMMARY OF OF SUBSURFACE CONDITIONS
o o z - z
-
LU o 0 >- m
ci
SC ALLUVIAL FLOOD-PLAIN DEPOSITS (Qa) - Mottled medium
brown to medium orange-brown, moist, medium dense, CLAYEY
SAND. -2 SA
-4
CAL 36 -6
-8
-10
.becomes loose. CAL 6 CON
-12
14
-16 CAL 14
-18
V Groundwater encountered at 20 feet.
DS 20 ____________________________________________________ (BORING LOG CONTINUED ON FIGURE 1-3)
SOUTHERN CALIFORNIA 4419 PARK DRIVE RESIDENTIAL LOT
((ST SOIL & TESTING, INC. By: AKN Date: 5/9/2013
Job Number: 1311056-2 Figure: 1-2
LOG OF EXPLORATORY BORING NUMBER B-I
Date Excavated: 4/22/2013 Logged by: AKN
Equipment: Hollow Stem Auger Project Manager: GBF
Surface Elevation (ft): N/A Depth to Water (ft): 20
SAMPLES C))
o
I- U) W
. >-
10 w 0 SUMMARY OF SUBSURFACE CONDITIONS H H
o D z D
w 0 >- m
CL ALLUVIAL FLOOD-PLAIN DEPOSITS (Qa) - Mottled medium - - - -
brown to medium gray, saturated, very soft to soft, SANDY CLAY. CAL 5
- 22
-24
SP1 5
-26
28
30 becomes stiff to very stiff. CAL 21
- 32
-34
SPT 22 -36
-38
-40— (BORING LOG CONTINUED ON FIGURE 1-4)
sè SOUTHERN CALIFORNIA 4419 PARK DRIVE RESIDENTIAL LOT
STI SOIL & TESTING, INC.By AKN Date 5/9/2013
'4 Job Number: 1311056-2 Figure: 1-3
LOG OF EXPLORATORY BORING NUMBER B-I
Date Excavated: 4/22/2013 Logged by: AKN
Equipment: Hollow Stem Auger Project Manager: GBF
Surface Elevation (ft): N/A Depth to Water (ft): 20
SAMPLES U)
. C.)
I- U) W 0 W z CL
-
'0 ui
> 0 SUMMARY OF SUBSURFACE CONDITIONS ,.... i-
o a z - 0 z UJ 2 °- 0
-J a
- CL ALLUVIAL FLOOD-PLAIN DEPOSITS Mal - Mottled medium - - -
• brown to medium gray, saturated, stiff to very stiff, SANDY CLAY. CAL 24
42
44
jD JP6orY7 - - -
46
148
GRADED SAND. SPT 28
-50
SPT 34
-52
-54
SANTIAGO FORMATION (Tsa) - Light greenish gray,very moist,
-56 hard, SANDY CLAYSTONE. SPT 31
-58
SP1 50/4' -60 - BORING TERMINATED AT 60 FEET. - - - - -
SOUTHERN CALIFORNIA 4419 PARK DRIVE RESIDENTIAL LOT
ST/ SOIL & TESTING, INC. By: AKN IDate: 5/9/2013
-I Job Number: 1311056-2 IFigure: 1-4
LOG OF EXPLORATORY BORING NUMBER B-2
Date Excavated: 4/22/2013 Logged by: AKN
Equipment: Hollow Stem Auger Project Manager: GBF
Surface Elevation (ft): N/A Depth to Water (ft): Groundwater not encountered
SAMPLES
:' 0
I-
)
W
z •8
0
-
a) W
W SUMMARY OF SUBSURFACE CONDITIONS
U)0
0 Z -
2
D o z o
8 a-—
0
0
Sc ALLUVIAL FLOOD-PLAIN DEPOSITS Mal - Mottled medium
brown to medium orange brown, moist, medium dense to dense,
CLAYEY SAND.
- 2
El
-4
- 6 CAL 47 CON
-8
-10 becomes dark brownish gray and very dense.
CAL 50/3 DS
- 12
-14
- SANTIAGO FORMATION (Tsa) - Light greenish gray, moist,
-16 dense to very dense, CLAYEY SANDSTONE. CAL 49
—18
1201 CAL 50/5 __________________________________________________________ BORING TERMINATED AT 20 FEET.
sc SOUTHERN CALIFORNIA 4419 PARK DRIVE RESIDENTIAL LOT
(s T SOIL & TESTING, INC. By: AKN Date: 5/9/2013
Job Number: 1311056-2 Figure: 1-5
U.S. Standard Sieve Sizes
6" 3" i-W 3/43/8 #4 #8 #10 #16 #30 #40#50 #100 #200
90
80
60
50
30
20
10
1000 100 10 1 0.1 0.01
Grain Size in Millimeters
Cobbles Gravel Sand Silt or Clay
Coarse I Fine Coarse Medium Fine
SAMPLE LOCATION UNIFIED SOIL CLASSIFICATION: Sc I ATTERBERG LIMITS B-i at 0 foot to 5 feet DESCRIPTION CLAYEY SAND LIQUID LIMIT -
PLASTIC LIMIT -
L PLASTICITY INDEX -
SOUTHERN CALIFORNIA
SOIL & TESTING INC.
4419 PARK DRIVE RESIDENTIAL LOT
By: AKN IDate: 5/9/2013
Job Number: 1311056-2 iFigure: Il-I
EXPANSION INDEX TEST RESULTS
ASTM 04829
SAMPLE IDENTIFICATION EXPANSION INDEX
B-2 at 0 foot to 5 feet 1 6
CLASSIFICATION OF EXPANSIVE SOIL
EXPANSION INDEX POTENTIAL EXPANSION
1-20 Very low
21-50 Low
51 -90 Medium
91-130 High
Above 130 Very High
4419 PARK DRIVE RESIDENTIAL LOT SOUTHERN CALIFORNIA
SOIL & TESTING, INC. By: AKN IDate: 5/9/2013
Job Number: 1311056-2 IF 11-2
Consolidation
Sample Location
B-I at 10 feet
Water Ad e
1-
2-
0
0
r. C)
a) 0
-------.
1
- 1 - 6 ----- ____
7 . -------- ____ --------- ____
0.1 1 10 100
Load Kips/Sq.Ft.
SOUTHERN CALIFORNIA 4419 PARK DRIVE RESIDENTIAL LOT
SOIL & TESTING, INC. By: AKN Date: 5/9/2013
Job Number: 1311056-2 Figure: 11-3
Consolidation
Sample Location
B-2 at 5 feet
0.5 IIi 1 U /atei Ad de
1.5
C 0
0
2.5
C.,
4-
3
3.5
4 ----- - ___
4.5
5
0.1 .1 10 100
Load Kips/Sq.Ft.
1 SOUTHERN CALIFORNIA 4419 PARK DRIVE RESIDENTIAL LOT
SOIL & TESTING, INC. By: AKN Date: 5/9/2013
-- Job Number: 1311056-2 Figure: 11-4
Direct Shear Test Results
5.0
4.5
4.0
Shear Strength at 0.2 inches of
Deformation
3_5
3.0 (I)
2.5 07
OV 400p
1.0
40 op
0.5
0.0
45 50
Confining Pressure (ksf)
INTERNAL.: COHESION
FRICTION - INTERCEPT SAMPLE DESCRIPTION ANGLE(DEG.) (PSF)
B-i at 20 feet IN-SITU SANDY CLAY (CL)
ar Strength at
28 345
SOUTHERN CALIFORNIA 4419 PARK.DRFVE RESIDENTIAL LOT
SOIL & TESTING AKN I Date: 5/9/2013
Number: 1311056-2 Figure: 11-5
INTERNAL COHESION
FRICTION INTERCEPT
SAMPLE DESCRIPTION ANGLE(DEG.) (PSF)
B-2 at 10 feet IN-SITU CLAYEY SAND (SC)
Shear Strength at
27 1022 0.2 inches of Deformation
L
4419 PARK DRIVE RESIDENTIAL LOT SC SOUTHERN CALIFORNIA
SOIL & TESTING By: AKN Date: 5/9/2013
Job Number: 1311056-2 Figure: 11-6
I
Direct Shear Test Results
::.i
4.0
Shear Strength at 0.2 inches of
Deformation
3.5 — — —
3.0
2.0
1.5
dop
0.5
0.0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
Confining Pressure (ksf)