HomeMy WebLinkAboutCDP 04-42; North County Pontiac/GMC; Geotechnical Engineering Investigation; 2004-04-08Geotechnical Engineering investigation
North County GMC/Pontiac Expansion Development
5425 Paseo Del Norte
Carlsbad, California
Prepared For:
The Automotive Group
450 West Vista Way
Vista, California 92083
Attn.: Mr. Frank Johnson
Project Number 11282-04
April 8, 2004
LJ \
NorCal Engineering
Soils and Geotechnical Consultants
10641 Humbolt Street Los Alamitos, CA 90720
(562) 799-9469 Fax (562) 799-9459
April 8, 2004 Project Number 11282-04
The Automotive Group
450 West Vista Way
Vista, California 92083
Attn.: Mr. Frank Johnson
RE: Geotechnical Engineering Investigation - Proposed North County
GMC/Pontiac Expansion Development - Located at 5425 Paseo Del
Norte, in the City of Carlsbad, California
Dear Mr. Johnson:
Pursuant to your request, this firm has performed a Geotechnical Engineering
Investigation for the above referenced project in accordance to our signed proposal
dated March 10, 2004. The purpose ofthis investigation is to evaluate the subsurface
conditions of the subject site and to provide recommendations for the proposed
development.
The scope of work included the following: 1) site reconnaissance; 2) subsurface
geotechnical exploration and sampling; 3) laboratory testing; 4) engineering analysis of
field and laboratory data; 5) and preparation of a geotechnical engineering report. It is
the opinion of this firm that the proposed development is feasible from a geotechnical
standpoint provided that the recommendations presented in this report are followed in
the design and construction of the project.
April 8 2004 p^^- ^ ^^^^^^^ 11282-04
rage 2
10 Proiect Description
It is proposed to construct a new service and part storage building and an addition to the
existing showroom for the North County GMC/Pontiac Dealership as shown on the
conceptual site plan. The new buildings are anticipated to have conventional slab-on-
grade foundation systems with perimeter-spread footings and isolated interior footings.
It is assumed that the proposed grading for the development will include minor cut and
fill procedures. Final building plans shall be reviewed by this firm prior to submittal for
city approvai to determine the need for any additional study and revised
recommendations pertinent to the proposed development, if necessary.
2.0 Site Description
The subject automobile dealership is situated within the North County Automobile
Center located within the 5400 block and west side of Paseo Del Norte, in the City of
Carlsbad. The generally triangular shaped parcel is elongated in a north to south
direction with topography of the relatively level property descending slightly from north to
south on the order of a few feet. The proposed development areas are situated toward
the northern portion of the dealership and are currently covered with asphalt pavement
and or landscaping.
3.0 Site Exploration
The investigation consisted of the placement of four (4) subsurface exploratory borings
by a hand-operated auger to a maximum depth of 15 feet below current ground
elevations. The explorations were visually classified and logged by a field engineer with
locations of the subsurface explorations shown on the attached Site Plan. The
exploratory borings revealed the existing earth materials to consist of a fill and natural
soil.
NorCal Engineering
,^PgLV°°' Project Number 11282-04
A detailed description of the subsurface conditions are listed on the excavation logs in
Appendix A. It should be noted that the transition from one soil type to another as
shown on the borings logs is approximate and may in fact be a gradual transition. The
soils encountered are described as follows:
Fill: A fill soil classifying as a brown to grey brown, silty SAND was encountered
and ranged in depth from 5 to 6 feet. These soils were noted to be dense and
moist.
Natural: An undisturbed alluvium soil classifying as a brown, silty SAND was
encountered beneath the fill soils. These native soils were observed to be dense
and moist.
The overall engineering characteristics of the earth material were relatively uniform with
each boring. No groundwater was encountered to the depth our borings and no caving
occurred.
4.0 Laboratorv Tests
Relatively undisturbed samples of the subsurface soils were obtained to perform
laboratory testing and analysis for direct shear, consolidation tests, and to determine in-
place moisture/densities. These relatively undisturbed ring samples were obtained by
driving a thin-walled steel sampler lined with one-inch long brass rings with an inside
diameter of 2.42 inches into the undisturbed soils.
Bulk bag samples were obtained in the upper soils for expansion index tests and
maximum density tests. Wall loadings on the order of 4.000 lbs./lin.ft. and maximum
compression loads on the order of 100 kips were utilized for testing and design
purposes. All test results are included in Appendix B, unless otherwise noted.
4.1 Field moisture content (ASTMiD 2216) and the dry density of the ring samples were
determined in the laboratory. This data is listed on the logs of explorations.
NorCal Engineering
April 8, 2004 Project Number 11282-04
Page 4
4.2 IVIaximum density tests (ASTM: D-1557-00) were perfomied on typical samples of the
upper soils. Results of these tests are shown on Table I.
4.3 Expansion Index tests in accordance with the Uniform Building Code Standard No. 18-
2 were performed on remolded samples of the upper soils. Results of these tests are
provided on Table II.
4.4 Atterberg Limits (ASTM: D 4318-84) consisting of liquid limit, plastic limit and plasticity
index were performed on representative soil samples. Results are shown on Table III.
4.5 Corrosion tests consisting of sulfate, pH, resistivity and chloride analysis to determine
potential corrosive effects of soils on concrete and underground utilities were performed
in the laboratory. Test results are provided on Table IV.
4.6 Direct shear tests (ASTM: D-3080) were performed on undisturbed and disturbed
samples of the subsurface soils. The test is performed under saturated conditions at
loads of 500 Ibs./sq.ft.. 1.000 Ibs./sq.ft, and 2,000 Ibs./sq.ft. with results shown on
Plates A and B.
4.7 Consolidation tests (ASTM: D-2435) were performed on undisturbed samples to
determine the differential and total settlement which may be anticipated based upon the
proposed loads. Water was added to the samples at a surcharge of one KSF and the
settlement curves are plotted on Plates C and D.
5.0 Seismicitv Evaluation
There are no known active or potentially active faults trending toward or through the site.
The proposed development lies outside of any Alquist Priolo Special Studies Zone and
the potential for damage due to direct fault rupture is considered very remote. The site
is located in an area of high regional seismicity and a peak horizontal ground
acceleration of 0.47g may occur from a Magnitude 6.9 earthquake along the Newport-
Inglewood fault zone, which is located approximately 4 miles away.
NorCal Engineering
April 8, 2004 Project Number 11282-04
Page 5
Ground shaking originating from earthquakes along other active faults in the region is
expected to induce lower horizontal accelerations due to smaller anticipated
earthquakes and/or greater distances to other faults. The following earthquake design
parameters are based upon the 1997 Unifomi Building Code (UBC) for a Seismic Zone
4 with a Z factor of 0.40 and a Soil Profile Type of So, a stiff soil profile.
1997 UBC Seismic Design Parameters
Distance from Site (Rose Canyon Fault) 7 km
Seismic Source Type B
Seismic Coefficient = Ca (Table 16-Q) (0.44) Na
Seismic Coefficient = Cv (Table 16-R) (0.64) Nv
Near-Source Factor Na (Table 16-S) 1.0
Near-Source Factor Nv (Table 16-T) 1.13
6.0 Liquefaction Evaluation
The site is expected to experience ground shaking and earthquake activity that is typical
of Southern Califomia area. It is during severe ground shaking that loose, granular soils
below the groundwater table can liquefy. Our analysis indicates the potential for
liquefaction at this site is considered to be very low due to the depth of groundwater in
excess of 50 feet within the vicinity area. Thus, the design of the proposed construction
in conformance with the latest Building Code provisions for earthquake design is
expected to provide mitigation of ground shaking hazards that are typical to Southern
California.
7.0 Conclusions and Recommendations
Based upon our evaluations, the proposed development is acceptable from a
geotechnical engineering standpoint. By following the recommendations and guidelines
set forth in our report, the structures and grading will be safe from settlements under the
anticipated design loadings and conditions. The proposed development shall meet all
requirements of the City Building Ordinance and will not impose any adverse effect on
exisfing adjacent stmctures.
NorCal Engineering
April 8 2004 Proiect Number 11282-04 Page 6
The following recommendations are based upon geotechnical condifions encountered in
our field investigation and laboratory data. Therefore, these surface and subsurface
conditions could vary across the site. Variafions in these condifions may not become
evident unfil the commencement of grading operafions and any unusual conditions
which may be encountered in the course of the project development may require the
need for additional study and revised recommendations.
It is recommended that site inspecfions be performed by a representative of this firm
during all grading and constmction of the development to verify the findings and
recommendations documented in this report. The following sections present a
discussion of geotechnical related requirements for specific design recommendations of
different aspects of the project.
7.1 Site Gradinq Recommendations
Any demolition debris shall be removed and hauled from proposed grading areas prior
to the start of grading operations. Existing vegetation shall not be mixed or disced into
the soils. Any removed soils may be reutilized as compacted fill once any deleterious
material or oversized materials (in excess of eight inches) is removed. Grading
operations shall be performed in accordance with the attached "Specifications for
Compacted Fill Operations".
All disturiied surface soils (about one foot) shall be removed to competent material
{>90% relative compaction), the exposed surface scarified to a depth of 12 inches,
brought to within 2% of optimum moisture content and compacted to a minimum of 90%
of the laboratory standard (ASTM: D-1557) prior to placement of any additional
compacted fill soils, foundations, slabs-on-grade and pavement. Grading shall extend a
minimum of five horizontal feet outside the edges of foundations or equidistant to the
depth of fill placed, whichever is greater.
NorCal Engineering
April 8. 2004 Project Number 11282-04
F*age 7
It is possible that isolated areas of undiscovered fill, not described in this report are
present on site. If found, these areas should be treated as discussed eariier. A diligent
search shall also be conducted during grading operations in an effort to uncover any
underground structures, irrigation or utility lines. If encountered, these structures and
lines shall be either removed or properiy abandoned prior to the proposed construction.
Any imported fill material should be preferably soil similar to the upper soils encountered
at the subject site. All soils shall be approved by this firm prior to importing at the site
and will be subjected to additional laboratory testing to assure concurrence with the
recommendations stated in this report.
Care should be taken to provide or maintain adequate lateral support for all adjacent
improvements and structures at all times during the grading operations and construction
phase. Adequate drainage away from the structures, pavement and slopes should be
provided at all times.
If placement of slabs-on-grade and pavement is not completed immediately upon
completion of grading operations, additional testing and grading of the areas may be
necessary prior to continuation of construction operations. Ukewise, if adverse weather
conditions occur which may damage the subgrade soils, additional assessment by the
geotechnical engineer as to the suitability of the supporting soils may be needed.
7.2 Temporai-v Excavations
Temporary unsurcharged excavations in the existing site materials less than 4 feet high
may be made at a vertical gradient unless cohesionless soils are encountered.
Temporary unsurcharged excavations above the vertical from 4 to 8 feet high may be
trimmed at a 1 to 1 (horizontal to vertical) gradient. In areas where soils with little or no
binder are encountered, where adverse geological conditions are exposed, or where
excavations are adjacent to existing structures, shoring, slot-cutting, or flatter
excavations may be required. The temporary cut slope gradients given do not preclude
local raveling and sloughing.
NorCal Engineering
April 8, 2004 Project Number 11282-04
Page 8
All excavations shall be made in accordance with the requirements of CAL-OSHA and
other public agencies having jurisdiction. Care should be taken to provide or maintain
adequate lateral support for all adjacent improvements and structures at all times during
the grading operations and constmction phase.
7.3 Foundation Desiqn
All foundations may be designed utilizing the following safe bearing capacities for an
embedded depth of 18 inches into approved compacted fill materials or competent
native soils with the corresponding widths:
Allowable Safe Bearing Capacitv fpsfi
Continuous Isolated
Width (ft) Foundation Foundation
1 -5 2000 2500
2.0 2075 2575
4.0 2375 2875
6.0 2675 3175
The bearing value may be increased by 500 psf for each additional foot of depth in
excess of the 18-inch minimum depth, up to a maximum of 4,000 psf. A one third
increase may be used when considering short-term loading and seismic forces. A
representative of this firm shall inspect all foundation excavations prior to pouring
concrete.
7.4 Settlement Analvsis
Resultant pressure curves for the consolidation tests are shown on Plate B.
Computations utilizing these curves and the recommended safe bearing capacities
reveal that the foundations will experience settiements on the order of 3/4 inch and
differential settlements of less than 1/4 inch.
NorCal Engineering
April 8, 2004 Project Number 11282-04
Page 9
7.5 Lateral Resistance
The following values may be utilized in resisting lateral loads imposed on the stmcture.
Requirements of the Uniform Building Code should be adhered to when the coefficient
of friction and passive pressures are combined.
Coefficient of Friction - 0.40
Equivalent Passive Fluid Pressure = 250 lbs./cu.ft.
Maximum Passive Pressure = 2,500 Ibs./cu.ft.
The passive pressure recommendations are valid only for approved compacted fill soils.
7.6 Retaining Wall Design Parameters
Active earth pressures against retaining walls will be equal to the pressures developed
by the following fluid densifies. These values are for granular backfill material placed
behind the walls at various ground slopes above the walls.
Surface Slope of Retained Materials Equivalent Fluid
(Horizontal to Vertical) Densitv fib./cu.ft.)
Level 30
5 to 1 35
4 to 1 38
3 to 1 40
2 to 1 45
Any applicable short-term construction surcharges and seismic forces should be added
to the above lateral pressure values. A backfill zone of non-expansive material shall
consist of a wedge beginning a minimum of one horizontal foot from the base of the wall
extending upward at an inclination no less than 1/4 to 1 (horizontal to vertical). All walls
shall be waterproofed as needed and protected from hydrostatic pressure by a reliable
permanent subdrain system.
NorCal Engineering
April 8, 2004 Project Number 11282-04
Page 10
7.7 Slab Design
All concrete slabs shall be at least five inches in thickness in service bay areas and four
inches in office and sidewalk areas and placed on approved subgrade soils.
Reinforcement requirements and an increase in thickness of the slabs may be
necessary based upon proposed loading conditions in the structures. All subgrade soils
shall be moistened to over optimum moisture content immediately prior to pouring of
concrete. All concrete slab areas to receive floor coverings should be moisture tested to
meet all manufacturer requirements prior to placement.
7.8 Pavement Section Design
The table below provides a preliminary pavement design based upon an estimated R-
Value of 40 for the proposed pavement areas. Final pavement design may need to be
based on R-Value testing of the subgrade soils near the conclusion of rough grading to
assure that these soils are consistent with those assumed in this preliminary design.
Traffic Asphaltic Base
Type of Traffic Index Concrete fin) Material (in)
Parking Stalls 4.0 3.0 3.0
Light Vehicle 5.0 3.0 4.0
Circulation Areas
Medium Tmck Access Areas 6.0 3.5 5 5
(GVW < 42,000 lbs.; 3 axle)
All concrete slabs to be utilized for pavement shall be a minimum of six inches in
thickness and placed on approved subgrade soils. In addition, the above
recommendations are based upon estimated traffic loads. Client should submit
anticipated traffic loadings, when available, so that pavement sections may be reviewed
to determine adequacy to support these loads.
NorCal Engineering
Apr\\ 8. 2004 Project Number 11282-04
Page 11
Any approved base material shall consist of a Class II aggregate or equivalent and
should be compacted to a minimum of 95% relative compaction. All pavement materials
shall conform to the requirements set forth by the City of Carlsbad. The base material
and asphaltic concrete should be tested prior to delivery to the site and during
placement to determine conformance with the project specifications. A pavement
engineer shall designate the specific asphalt mix design to meet the required project
specificafions.
7.9 Utiiitv Trench and Excavation Baclrfill
Trenches from installation of utility lines and other excavations may be backfilled with
on-site soils or approved imported soils compacted to a minimum of 90% relative
compaction. All utility lines shall be properly bedded with clean sand having a sand
equivalency rating of 30 or more. This bedding material shall be thoroughly water jetted
around the pipe structure prior to placement of compacted backfill soils.
7.10 Corrosion Design Criteria
Representative samples of the surficial soils, typical of the subgrade soils expected to
be encountered within foundation excavations and underground utilities were tested for
corrosion potential. The minimum resistivity value obtained for the samples tested is
representative of an environment that may be severely corrosive to metals. The soil pH
value was considered mildly alkaline and may have a significant effect on soil
corrosivity. Consideration should be given to corrosion protection systems for buried
metal such as protective coatings, wrappings or the use of PVC where permitted by
local buiiding codes.
According to the latest 'Unifomi Building Code (UBC) Table 19A-A-4 - Requirements for
Concrete Exposed to Sulfate-Containing Solutions', these contents revealed negligible
levels of sulfate exposure. Therefore, a Type II cement according to latest UBC
specificafions may be utilized for building foundations at this time. Additional sulfate
tests shall be performed at the completion of site grading to assure that these soils are
consistent with the recommendations stated in this design. Con-osion test results may
be found on the attached Table IV.
NorCal Engineering
April 8, 2004
Page 12 Project Number 11282-04
8.0 Closure
The recommendations and conclusions contained in this report are based upon the soil
conditions uncovered in our test excavations. No warranty of the soil condition between
our excavations is implied. NorCal Engineering should be notified for possible further
recommendations if unexpected to unfavorable conditions are encountered during
construction phase. It is the responsibility of the owner to ensure that all information
within this report is submitted to the Architect and appropriate Engineers for the project.
This firm should have the opportunity to review the final plans to verify that all our
recommendations are incorporated. This report and all conclusions are subject to the
review of the controlling authorities for the project.
A preconstmction conference should be held between the developer, general contractor,
grading contractor, city inspector, architect, and soil engineer to clarify any questions
relating to the grading operations and subsequent construction. Our representative
should be present during the grading operations and construction phase to certify that
such recommendations are complied within the field.
This geotechnical investigation has been conducted in a manner consistent with the
level of care and skill exercised by members of our profession currentiy practicing under
similar conditions in the Southern California area. No other warranty, expressed or
implied is made.
We appreciate this opportunity to be of service to you. If you have any further
questions, please do not hesitate to contact the undersigned.
Respectfully submitted,
NORCAL ENGINEERING
Keith D. Tucker
Project Engineer
R.G.E. 841
Scott D. Spensiero
Project Manager
NorCal Engineering
April 8 2004 Project Number 11282-04 rage 13
SPECIFICATIONS FOR PLACEMENT OF COMPACTED FILL
Excavation
Any existing low density soils and/or saturated soils shall be removed to competent
natural soil under the inspection of the Soils Engineering Firm. After the exposed
surface has been cleansed of debris and/or vegetation, it shall be scarified until it is
uniform in consistency, brought to the proper moisture content and compacted to a
minimum of 90% relative compaction (in accordance with ASTM: D-1557).
In any area where a transition between fill and native soil or between bedrock and soil
are encountered, additional excavation beneath foundations and slabs will be necessary
in order to provide uniform support and avoid differential settlement of the structure.
Material For Fill
The on-site soils or approved import soils may be utilized for the compacted fill provided
they are free of any deleterious materials and shall not contain any rocks, brick,
asphalfic concrete, concrete or other hard materials greater than eight inches in
maximum dimensions. Any import soil must be approved by the Soils Engineering firm
a minimum of 24 hours prior to importation of site.
Placement of Compacted FIII Soils
The approved fill soils shall be placed in layers not excess of six inches in thickness.
Each lift shall be uniform in thickness and thoroughly blended. The fill soils shall be
brought to within 2% of the optimum moisture content, unless othen/vise specified by the
Soils Engineering firm. Each lift shall be compacted to a minimum of 90% relative
compaction (in accordance with ASTM: D-1557) and approved prior to the placement of
the next layer of soil. Compaction tests shall be obtained at the discretion of the Soils
Engineering firm but to a minimum of one test for every 500 cubic yards placed and/or
for every 2 feet of compacted fill placed.
NorCal Engineering
^Pge'l4°°' Project Number 11282-04
The minimum relative compaction shall be obtained in accordance with accepted
methods in the constmction industry. The final grade of the stmctural areas shall be in a
dense and smooth condition prior to placement of slabs-on-grade or pavement areas.
No fill soils shall be placed, spread or compacted during unfavorable weather conditions.
When the grading is intermpted by heavy rains, compaction operations shall not be
resumed until approved by the Soils Engineering firm.
Grading Observations
The controlling govemmental agencies should be notified prior to commencement of any
grading operations. This firm recommends that the grading operations be conducted
under the observation of a Soils Engineering firm as deemed necessary. A 24 hour
notice must be provided to this firm prior to the time of our initial inspection.
Observation shall include the clearing and gmbbing operafions to assure that all
unsuitable materials have been properiy removed; approve the exposed subgrade in
areas to receive fill and in areas where excavation has resulted in the desired finished
grade and designate areas of overexcavation; and perform field compaction tests to
determine relative compaction achieved during fill placement. In addition, all foundation
excavations shall be observed by the Soils Engineering firm to confirm that appropriate
bearing materials are present at the design grades and recommend any modificafions to
construct footings.
NorCal Engineering
PASEO DEL NORTE
9
1 INCH ' 80 FEET NorCal Engineering
SOILS AND GEOTECHNICAL CONSULTANTS
PROJECT 11282-04 WTE APRIL 2004
SITE PLAN
APPROXIMATE LOCATION OF FILED EXPLORATIONS
April 8, 2004 Project Number 11282-04
Page 15
List of Appendices
(in order of appearance)
Appendix A - Log of Excavations
• Log of Borings B-1 to B-4
• Appendix B - Laboratorv Tests
• Table I - Maximum Dry Density
• Table II - Expansion
• Table III - Atterberg
• Table IV - Corrosion
• Plate A - Direct Shear
• Plate B - Consolidation
NorCal Engineering
April 8, 2004 Project Number 11282-04
Appendix A
NorCal Engineering
MAJOR DIVISION GRAPHIC
.<$YMRni
LETTER
.SYMROI
TYPICAL DESCRIPTIONS
COARSE
GRAINED
SOILS
MORE THAN
50% OF
MATERIAL
IS LARGER
THAN NO.
200 SIEVE
SIZE
GRAVEL
AND
GRAVELLY
SOILS
MORE THAN
50% OF
COARSE
FRACTION
RETAINED QN
NO. 4 SIEVE
SAND
AND
SANDY
SOILS
MORE THAN
50% OF
COARSE
FRACTION
PASSING ON
NO. 4 SIEVE
CLEAN GRAVELS
(LITTLE OR NO
FINES)
o Oo GW WELL-GF5ADED GRAVELS, GRAVEL.
SANO MIXTURES, LITTLE OR NO FINES
GP POORLY-GRADED GRAVELS,
GRAVEL-SAND MIXTURES, LITTLE
OR NO FINES
GRAVELS
WITH FINES
(APPRECIABLE
AMOUNT OF
FINESl
GM SILTY GRAVELS, GRAVEL-SAND-
SILT MIXTURES
GC CLAYEY GRAVELS, GRAVEL-SAND-
CLAY MIXTURES
CLEAN SAND
(LITTLE OR NO
FINES)
1 m^ m^m
SW WELL-GRADED SANDS. GRAVELLY
SANDS. LITTLE OR NO FINES
SP POORLY-GRADED SANDS. GRAVEL-
LY SANDS, LITTLE OR NO FINES
SANDS WITH
FINE
(APPRECIABLE
AMOUNT OF
FINES)
SM SILTY SANDS, SAND-SILT
MIXTURES
SC CLAYEY SANDS, SAND-CLAY
MIXTURES
FINE
GRAINED
SOILS
MORE THAN
50% OF
MATERIAL
ISSfi^EB
THAN NO.
200 SIEVE
SIZE
SILTS
ANO
CLAYS
LIQUID LIMIT
I P.'5.'5 THAN
SILTS
AND
CLAYS
LIQUID LIMIT
GREATER THAN
50
ML
INORGANIC SILTS AND VERY FINE
SANDS, ROCK FLOUR, SILTY OR
CLAYEY FINE SANDS OR CLAYEY
SILTS WITH SLIGHT PLASTICITY
CL
INORGANIC CLAYS OF LOW TO
MEDIUM PLASTICITY, GRAVELLY
CLAYS, SANDY CLAYS, SILTY
CLAYS. LEAN CLAYS
OL ORGANIC SILTS AND ORGANIC
SILTY CLAYS OF LOW PLASTICITY
MH INORGANIC SILTS, MICACEOUS OR
DIATOMACEOUS FINE SAND OR
SILTY SOILS
CH INORGANIC CLAYS OF HIGH
PLASTICITY. FAT CLAYS
OH ORGANIC CLAYS OF MEDIUM TO
HIGH PLASTICITY, ORGANIC SILTS
HIGHLY ORGANIC SOILS PT
PEAT. HUMUS, SWAMP SOILS WITH
HIGH ORGANIC CONTENTS
NOTE: DUAL SYMBOLS ARE USED TO INDICATE BORDERLINE SOIL CLASSIFICATIONS
UNIFIED SOIL CLASSIFICATION SYSTEM
NorCal Engineering
KEY:
CD
C
•
B
•I
QCI
Indicates 2.5-inch Inside Diameter. Ring Sample.
Indicates 2-inch OD Split Spoon Sample (SPT).
Indicates Shelby Tube Sample.
Indicates No Recovery.
Indicates SPT with 140# Hammer 30 in. Drop.
Indicates Bulk Sample.
Indicates Small Bag Sample.
Indicates Non-Standard
Indicates Core Run. COIVIPONENT PROPORTIONS
COMPONENT DEFINITIONS
COMPONENT SIZE RANGE
Boulders
Cobbles
Gravel
Coarse gravel
Fine gravel
Sand
Coarse sand
Medium sand
Fine sand
Silt and Clav
Larger lhan 12 in
3 in lo 12 in
3 in lo No 4 (4.5mm )
3 in to 3/4 in
3/4 in lo No 4 ( 4.5mm )
No. 4 ( 4.5mm ) to No. 200 ( 0.074mm )
No. 4 (4.5 mm ) to No. 10 (2.0 mm)
No. 10 ( 2.0 mm ) to No. 40 ( 0.42 mm )
No. 40 ( 0.42 mm ) to No. 200 ( 0.074 mm )
Smaller than No. 200 { 0.074 mm )
DESCRIPTIVE TERMS RANGE OF PROPORTION
Trace 1 - 5%
Few 5 - 10%
Little 10-20%
Some 20 - 35%
And 35 - 50%
MOISTURE CONTENT
DRY Absence of moisture, dusty,
dry to the touch.
DAMP Some perceptible
moisiure; below optimum
MOIST No visible water near optimum
moisture content
WET Visible fi^e water, usually
soil is below water table.
RELATIVE DENSITY OR CONSISTENCY VERSUS SPT N -VALUE
COHESIONLESS SOILS COHESIVE SOILS
Density N (blows/ft) Consistency N (blows/ft) Approximate
Undrained Shear
Strength (psO
Very Loose Olo 4 Very Sofl Oto 2 <250 Loose 4 to 10 Soft 2to4 250 - 500
Medium Dense 10 to 30 Medium Stiff 4to8 500 -1000 Dense 30 to 50 Stiff 8 to 15 1000-2000
Very Dense over 50 Very Stiff 15 to 30 2000 - 4000
Hard over 30 >4000
NorCal Engineering
Log of Boring B-1
Project: The Automotive Group/Carisbad
Date of Drilling: 3/30/04 Groundwater Deptii: None Encountered
Drilling Method: Hand Auger
Hammer Weiglit: Drop:
15
20
-25
30
- 35
Geotechnical Description
Surface Elevation: Not Measured
FILL
Silty SAND
Dark brown to grey-brown, dense, damp to moist
NATURAL
Silty SAND
Brown to grey-brown, dense to very dense, moist
10 !
Boring completed at depth of 15'
NorCal Engineering
Litli-ology
Project No.
11282-04
a
9.2
8.1
10.9
8.9
115.4
113.6
112.7
115.0
Log of Boring B-2
j Project: The Automotive Group/Carlsbad
Date of Drilling: 3/30/04 Groundwater Oepth: None Encountered
Drilling Metiiod: Hand Auger
Hammer Weiglit: Drop:
Geotechnical Description
Surface Elevation: Not Measured
TILL ~
Silty SAND
Brown to light brown, medium dense, moist
Lith-ology 1 =
O 3
= 5
I?
o' Q S3 o
I?
10
15
20
25
30
35
I-I NATURAL
I Silty SAND
! Reddish-brown, dense, moist
Boring completed at depth of 10"
8.9
11.0
112.2
116.3
NorCal Engineering Project No.
11282-04
11.7 113.7
Log of Boring B-3 1
Project: The Automotive Group/Carisbad
Samoies Laboratorv 1
Date of Drilling: 3/30/04 Groundwater Depth: None Encountered
Samoies Laboratorv 1
Drilling Method: Hand Auger
Samoies Laboratorv 1
Hammer Weight:
Deoth
Drop:
Samoies Laboratorv 1
(feet)
-5
10
15
20
25
30
35
Geotechnical Description
Surface Elevation: Not Measured
FILL
Silty SAND
Brown, dense, damp to moist
NATURAL
Silty SAND
Reddish-brown, dense, moist
Boring completed at depth of 10'
NorCal Engineering
Lith ology |l
o a
~ o m
Project No.
11282-04
I-o
7.6
7.6
9.4
11.3
Q
112.9
111.7
116.5
113.0
M
Log of Boring B-4
Project: The Automotive Group/Carlsbad
Date of Drilling: 3/30/04
Drilling Method: Hand Auger
Groundwater Depth: None Encountered
Hammer Weight:
Depth
(feet)
10
15
20
25
6
rt
30
35
Drop:
Geotechnical Description
Surface Elevation: Not Measured
[^Asphalt Pavement (2.5' thickness)
j FILL
! Silty SAND
i Brown, dense, moist
NATURAL
Silty SAND
Orange-brown, dense, damp to moist
Lith ology
Boring completed at depth of 12'
NorCal Engineering
Samples
w
11 ffl
Project No.
11282-04
1
I?
Laboratory
8.7
6.5
Q S tt
Q
117.8
115.9
7.2 110.9
M
April 8. 2004 Project Number 11282-04
Appendix B
NorCal Engineering
April 8. 2004 Project Number 11282-04
Sample
B-1 @ 2-3'
Classification
Silty SAND
TABLE I
MAXIMUM DENSITY TESTS
(ASTM: D.1557>
Optimum
Moisture
10.5
Maximum Dry
Densitv flbs./cu.ft.)
124.0
Soil Type
B-1 @ 2-3'
TABLE II
EXPANSION INDEX TESTS
(U.B.C. STD. 18-2^
Classification
Silty SAND
Expansion
Index
04
Sample
B-1 @ 0-4'
B-1 @ 9-12'
TABLE III
ATTERBERG LIMITS
Liquid Limit Plastic Limit
22 17
24 18
Plasticity Index
5
6
Sample pH
B-1 @ 2-3' 7.4
TABLE IV
CORROSION TESTS
Electrical Resistivitv fohm-cm)
1,360
Sulfate (%) Chloride (ppm)
0.023 85
ND denotes not detected
% by weight
ppm - mg/kg
NorCal Engineering
2500
500 1000 1500 2000
NORMAL STRESS (PSF)
2500 3000
SYMBOL B0RIN6
NUMBER
DEPTH
(FEET) fi
(DEGREES)
C
(PSF)
ORY
DENSITY
(PCF)
MOISTURE
CONTENT
{%)
X 1 2 34 100 115.4 9.2
O 3 2 31 100 112.9 7.6 A 4 2 30 125 117.8 * * ^
8.7 •
NOTE: TESTS PERFORMED ON SATURATED SAMPLES UNLESS SHOWN BELOW
(FM) FIELD MOISTURE
TESTS PERFORMED ON UNDISTURBED SAMPLES UNLESS SHOWN BELOM.
(R) SAMPLES REMOLDED AT 90% OF MAXIMUM DRY DENSITY
NorCal Engineering
SOILS AND GEOTECHNICAL CONSULTANTS DIRECT SHEAR TEST RESULTS
Plate A
DIRECT SHEAR TEST RESULTS
Plate A
PROJECT 11282-04 OATE
DIRECT SHEAR TEST RESULTS
Plate A
1.0 5
NORMAL PRESSURE (KSF)
SVMBOL BORING
NUHBER
DEPTH
(FEET)
DRY
DENSITY
(PCF)
MOISTURE
CONTENT
(I)
LIQUID
LIMIT
(X)
PLASTICITY
INDEX
(«)
X 1 5 113.fi R-1
O 1 10 112.7 10.9
A 4 10 110.9 ^ 7.2
•
REBOUND (R) SAMPLE REMOLDED AT 90X OF MAXIMUM DRY DENSITY
NorCal Engineering
SOILS AND GEOTECHMCAL CONSULTANTS
PROJECT 11282-04 DATE
CONSOLIDATION TEST RESULTS
Plate B