HomeMy WebLinkAboutCDP 2019-0032; TELESCOPE HOUSE: BUILD NEW SFR; GEOTECHNICAL INVESTIGATION; 2019-03-11GEOTECHNICAL INVESTIGATION
Proposed Single-Family Residence
4615 Telescope Avenue
Carlsbad, California
JUL 07 ZOZU
LAND DEVELOPMENT
ENGI NEERING
HETHERNGTON ENGNEERING, kNC.
ONC.
SOIL & FOUNDATION ENGINEERING • ENGINEERING GEOLOGY ' HYDROGEOLOGY
March 11, 2019
Project No. 8787.1
Log No. 20349
Elite Home Construction, Inc.
2386 Ivy Road
Oceanside, California 92054
Attention: Mr. Corey Love
Subject: GE0TEC}II1ICAL INVESTIGATION
Proposed Single-Family Residence
4615 Telescope Avenue
Carlsbad, California
References: Attached
Dear Mr. Love:
In accordance with your request, we have performed a geotechnical investigation for a
proposed single-family residence at the subject site. Our work was performed during
February and March 2019. The purpose of our investigation was to evaluate the soil and
geologic conditions at the site in order to provide grading and foundation
recommendations for the proposed development.
Our scope of work included the following:
Research and review of available plans and geologic maps/literature pertinent to the
site (see References).
Subsurface exploration consisting of two borings for soil sampling and geologic
observation.
Laboratory testing of samples obtained from the subsurface exploration.
Engineering and geologic analysis.
Preparation of this report presenting the results of our field and laboratory work,
analyses, and our conclusions and recommendations.
5365 Avenida Ericinas, Suite A • Carlsbad, CA 92008-4369 • (760) 931-1917 • Fax (760) 931-0545
333 Third Street, Suite 2 • Laguna Beach, CA 92651-2306 • (949) 715-5440 • Fax (760) 931-0545
www.hetheringtonengineering.com
GEOTECHNICAL INVESTIGATION
Project No. 8787.1
Log No. 20349
March 11, 2019
Page 2
SITE DESCRIPTION
The subject property is located at 4615 Telescope Avenue, Carlsbad, California (see
Location Map, Figure 1). The irregular shaped properly is approximately 7000±-square-
feet in size. The site currently consists of a relatively level graded pad with a 10±-feet
high slope that descends to Telescope Avenue and a 10±-feet high slope that ascends to a
residential property to the west. The site is bounded by developed residential properties to
the north, south and west, and by Telescope Avenue to the east.
PROPOSED DEVELOPMENT
Proposed development consists of a single-family residence. We anticipate a one-story,
wood-frame structure founded on conventional continuous/spread footings with slab-on-
grade ground floors. The garage will be at Telescope Avenue grade and the residence on
the upper pad level. Building loads are expected to be typical for this type of relatively
light construction. Proposed grading consists of cut to a maximum depth of
approximately 10±-feet to facilitate the street level garage. Retaining walls up to
approximately 10±-feet high are proposed to facilitate grade changes.
SUBSURFACE EXPLORATION
Subsurface conditions were explored by excavating two hollow-stem auger borings to
depths of 16 to 20-feet below existing site grades. The approximate locations of the
exploratory borings are shown on the attached Plot Plan, Figure 2 and Geologic Cross-
Section, Figure 3.
The subsurface exploration was supervised by an engineer from this office, who visually
classified the soil, and obtained relatively undisturbed and bulk soil samples for
laboratory testing. The soils were visually classified according to the Unified Soil
Classification System. Classifications are shown on the attached Boring Logs, Figures 4
and 5.
LABORATORY TESTING
Laboratory testing was performed on samples obtained during the subsurface exploration.
Tests performed consisted of the following:
Dry Density/Moisture Content ASTM: D 2216)
Direct Shear (ASTM: D 3080)
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SCALE: V-2000'
(1 Grid Equals: 0.5 x 0.5 miles)
LOCATION MAP
4615 Telescope Avenue HETHERINGTON ENGINEERING, INC. Carlsbad, California
GEOTECHNICAL CONSULTANTS PROJECT NO. 8787.1 1 FIGURE NO. 1
GEOTECHNICAL INVESTIGATION
Project No. 8787.1
Log No. 20349
March 11, 2019
Page 3
Maximum Dry Density/Optimum Moisture (ASTM: D 1557)
Expansion Index (ASTM: D 4829)
Soluble Sulfate (Cal Test 417)
Results of the dry density and moisture content determinations are presented on the
attached Boring Logs, Figures 4 and 5. The remaining laboratory test results are
presented on the attached Laboratory Test Results, Figure 6.
GRADING HISTORY
Research at 'the city of Carlsbad resulted in obtaining grading plans and geotechnical
reports (References 9 through 12). The grading plan has been utilized in the preparation
of the attached Plot Plan, Figure 2. The site is reportedly entirely a cut lot exposing
Terrace Deposits.
SOIL AND GEOLOGIC CONDITIONS
1. Geologic Setting
The subject site lies within a relatively level marine terrace that is contained within
the coastal plain region of northern San Diego County, California. The coastal plain
region is characterized by numerous regressive marine terraces of Pleistocene age that
have been established above wave-cut platforms of underlying Eocene bedrock and
were formed during glacio-eustatic changes in sea level. The terraces extend from
areas of higher elevations east of the site and descend generally west-southwest in a
"stairstep" fashion down to the present day coastline. These marine terraces increase
in age eastward. The site area is contained within the central portion of the USGS
San Luis Rey 7.5-minute quadrangle.
As observed in the borings, the site is underlain by Quaternary terrace deposits. The
terrace deposits consist of orange brown, light brown, tan and black clayey sand and
sand that is damp to moist and dense. Structurally, bedding within the terrace
deposits is considered to be essentially massive. The terrace deposits are granular and
have a very low expansion potential.
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GEOTECHNICAL INVESTIGATION
ProjectNo. 8787.1
Log No. 20349
March 11, 2019
Page 4
2. Groundwater
Groundwater or seepage was not encountered in the exploratory borings. It should be
noted, however, that fluctuations in the amount and level of groundwater may occur
due to variations in rainfall, irrigation and other factors that may not have been
evident at the time of our field investigation.
SEISMICITY
Based on review of the available geologic maps/literature, there are no active or
potentially active faults that traverse the subject site, and the property is not located
within the currently mapped limits of an Aiquist-Priolo Earthquake Fault Zone. The
following table lists the known active faults that would have the most significant impact
on the site:
Maximum Probable
Fault Earthquake Slip Rate
(Moment Magnitude) (mm/yea!')
Rose Canyon 7 5.0
(9.2-kilometers! 5.7-miles southwest)
Elsinore (Julian Segment) 6.8 3.0 (35- kilometers/ _21.7-miles northeast)
SEISMIC EFFECTS
Ground Accelerations
The most significant probable earthquake to affect the property would be a 7.0
magnitude earthquake on the Rose Canyon fault. Based on Section 1803.5.12 of the
2016 California Building Code and Section 11.8.3 of ASCE 7, peak ground
accelerations (PGAM) of 0.463g are possible for the design earthquake.
Landsliding
Review of the referenced geologic maps/literature indicates that the subject property
is not included within the limits of any previously mapped landsliding. The risk of
seismically induced landsliding affecting the site is considered low due to the dense
nature of the terrace deposits and favorable geologic structure.
HETHERUGTON ENGINEERING, INC
GEOTECHNICAL INVESTIGATION
Project No. 8787.1
Log No. 20349
March 11, 2019
Page 5
Ground Cracks
The risk of fault surface rupture due to active faulting is considered low due to the
absence of known active faults on site. Ground cracks due to shaking from seismic
events in the region are possible, as with all of southern California.
Liquefaction
The risk of seismically induced liquefaction within the site is considered low due to
the dense nature of the terrace deposits and absence of shallow groundwater.
Tsunamis
The site is not located within a mapped tsunami inundation area (Reference 2). The
risk of a tsunamis event adversely impacting the site is considered low due to the
elevation of the property above sea level.
CONCLUSIONS AND RECOMMENDATIONS
General
The proposed development is considered feasible from a geotechnical standpoint.
Grading and foundation plans should take into account the appropriate geotechnical
features of the site. Provided that the recommendations presented in this report and
good construction practices are utilized during design and construction, the proposed
construction is not anticipated to adversely impact the adjacent properties from a
geotechnical standpoint
Seismic Parameters for Structural Design
Seismic considerations that may be used for structural design at the site include the
following:
a. Ground Motion - The proposed structure should be designed and constructed to
resist the effects of seismic ground motions as provided in Section 1613 of the
2016 California Building Code.
Site Address: 4615 Telescope Avenue, Carlsbad, California
Latitude: 33.15240
Longitude: -117.31810
HETHERINGTON ENQIIVEERING, IIYC.
GEOTECHNICAL INVESTIGATION
Project No. 8787.1
Log No. 20349
March 11, 2019
Page 6
Spectral Response Accelerations - Using the location of the property and data
obtained from the U.S.G.S. Earthquake Hazard Program, short period Spectral
Response Accelerations S (0.2 second period) and Si (1.0 second period) are:
Ss= 1.11g
S = 0.426g
Site Class - In accordance with Chapter 20 of ASCE 7, and the underlying
geologic conditions, a Site Class D is considered appropriate for the subject
property.
Site Coefficients Fa and F, - In accordance with Table 1613.3.3 and considering
the values of Ss and Si, Site Coefficients for a Class D site are:
Fa = 1.506
F=1.574
Spectral Response Acceleration Parameters Sm and Smi - In accordance with
Section 1613.3.3 and considering the values of S and Si, and Fa and F, Spectral
Response Acceleration Parameters for the Maximum Considered Earthquake are:
Sm 1.172g
Smi =0.671g
Design Spectral Response Acceleration Parameters Sds and Sdi - In accordance
with Section 16 13.3.4 and considering the values of Sni and Smi, Design Spectral
Response Acceleration Parameters for the Maximum Considered Earthquake are:
Sd = 0.781g
Sdi = 0.447g
Long Period Transition Period - A Long Period Transition Period of TL = 8
seconds is provided for use in San Diego County.
Seismic Design Category - In accordance with Tables 1604.5, 1613.3.5(1) and
1613.3.5(2), and ASCE 7, a Risk Category II and a Seismic Design Category D
are considered appropriate for the subject property.
HETHEPNGTON ENGINEERING, INCA
GEOTECHNICAL INVESTIGATION
Project No. 8787.1
Log No. 20349
March 11, 2019
Page 7
Site Grading
Prior to grading, the site should be cleared of existing surface obstructions, vegetation
and debris. Materials generated during clearing should be disposed of at an approved
location off-site. Holes resulting from the removal of buried obstructions should be
filled with compacted fill or lean concrete. Seepage pits and/or septic systems, if
encountered during site development, should be abandoned in accordance with local
guidelines.
The garage level may be out to grade and is expected to expose competent terrace
deposits. For the upper building pad, within the limits of proposed residence and
hardscape and to 5-feet beyond, existing disturbed terrace deposits should be removed
down to approved undisturbed terrace deposits, estimated at 1 to 2-feet, and replaced
as compacted fill. Actual removal depths should be determined in the field by the
Geotechnical Consultant based on conditions exposed during grading.
The exposed subgrade soils should be scarified 6 to 8-inches, moisture conditioned to
about optimum moisture content and compacted by mechanical means to a minimum
relative compaction of 90-percent (ASTM: D 1557). Fill should be moisture
conditioned as necessary to about optimum moisture content and compacted by
mechanical means in uniform horizontal lifts of 6 to 8-inches in thickness. All fill
should be compacted to a minimum relative compaction of 90-percent based upon
ASTM: D 1557. The on-site materials are suitable for use as compacted fill provided
all vegetation and debris are removed. Rock fragments over 6-inches in dimension
and other perishable or unsuitable materials should be excluded from the fill.
All grading and compaction should be observed and tested as necessary by the
Geotechnical Consultant.
Temporary Slopes
Temporary slopes necessary to perform the remedial grading or to facilitate the
construction of the various retaining walls may be cut vertically up to 5-feet in terrace
deposits where the cuts are not influenced by existing structures or property line
constraints. Any portion of temporary slopes higher than 5-feet or located adjacent to
existing improvements should be inclined at a slope ratio no steeper than 1:1
(horizontal to vertical) or shored.
HETHERINGTON ENGINEERHG, INC.
GEOTECHINICAL INVESTIGATION
Project No. 8787.1
Log No. 20349
March 11, 2019
Page 8
Field observations by the Engineering Geologist during grading of temporary slopes
is recommended and considered necessary to confirm anticipated conditions and
provide additional recommendations as warranted.
5. Foundation and Slab Recommendations
The proposed structure may be supported on conventional continuous/spread footings
founded at least 18-inches into compacted fill and/or terrace deposits. Continuous
footings should be at least 12-inches wide and reinforced with a minimum of four #4
bars, two top and two bottom. Foundations located adjacent to utility trenches should
extend below a 1:1 (horizontal to vertical) plane projected upward from the bottom of
the trench.
Foundations bearing as recommended may be designed for a dead plus live load
bearing value of 2000-pounds-per-square-foot. This value may be increased by one-
third for loads including wind and seismic forces. A lateral bearing value of 250-
pounds-per-square-foot per foot of depth to a maximum value of 2000-pounds-per-
square-foot and a coefficient of friction between foundation soil and concrete of 0.35
may be assumed. These values assume that footings will be poured neat against the
foundation soils. Footing excavations should be observed by the Geotechnical
Consultant prior to the placement of reinforcing steel in order to verify that they are
founded in suitable bearing materials.
Total and differential settlement due to foundation loads is considered to be less than
3/4 and 3/8-inch, respectively, for foundations founded as recommended,
Slab-on-grade floors should have a minimum thickness of 5-inches, and should be
reinforced with #4 bars spaced at 18-inches, center to center, in two directions, and
supported on chairs so that the reinforcement is at mid-height in the slab. Floor slabs,
including the garage, should be underlain by a 10-mil polyethylene moisture vapor
retarder. At least 2-inches of sand should be placed, over the vapor retarder to assist
in concrete curing and at least 2-inches of sand should be placed below the vapor
retarder. The vapor retarder should be placed in accordance with ASTM: E 1643.
Prior to placing concrete, the slab subgrade soils should be thoroughly moistened.
Vapor retarders are not intended to provide a waterproofing function. Should
moisture vapor sensitive floor coverings be planned, a qualified consultant/contractor
should be consulted to evaluate moisture vapor transmission rates and to provide
recommendations to mitigate potential adverse impacts of moisture vapor
transmissions on the proposed flooring.
HETHERHGTON ENGINEERING, INC.
GEOTECHNICAL iNVESTIGATION
Project No. 8787.1
Log No. 20349
March 11, 2019
Page 9
6. Retaining Walls
Retaining walls free to rotate (cantilevered walls) should be designed for an active
pressure of 40-pounds-per-cubic-foot (equivalent fluid pressure). Walls restrained
from movement at the top should be designed for an at-rest pressure of 60-pounds-
per-cubic-foot (equivalent fluid pressure). These values are based on level backfill
consisting of onsite granular soils. Any additional surcharge pressures behind
retaining walls should be added to these values. Retaining wall foundations should be
designed in accordance with the foundation recommendations provided previously in
this report.
Retaining walls should be provided with adequate drainage to prevent buildup of
hydrostatic pressure and should be adequately waterproofed. The subdrain system
behind retaining wails should consist at a minimum of 4-inch diameter Schedule 40
(or equivalent) perforated (perforations "down") PVC pipe embedded in at least 1-
cubic-foot of 3/4 inch crushed rock per lineal foot of pipe all wrapped in an approved
filter fabric. The subdrain system should be connected to a solid outlet pipe with a
minimum of 1-percent fall that discharges to a suitable drainage device.
Recommendations for wall waterproofing should be provided by the Project Architect
and/or Structural Engineer.
The lateral pressure on retaining walls due to earthquake motions (dynamic lateral
force) should be calculated as PA = 3/8 y 1124 where
PA = dynamic lateral force (pounds-per-foot)
= unit weight = 120-pounds-per-cubic-foot
H = height of wall (feet)
kh = seismic coefficient = 0.154
The dynamic lateral force may also be expressed as 13.9-pounds-per-cubic-foot
(equivalent fluid pressure).
The dynamic lateral force is in addition to the static force and should be applied as a
triangular distribution at 1/3H above the base of the wall. The dynamic lateral force
need not be applied to retaining walls 6-feet or less in height.
HETHERHIGTON EGINEERH!G, INC.
GEOTECHNICAL INVESTIGATION
Project No. 8787.1
Log No. 20349
March 11, 2019
Page 10
Hardscape
Concrete flatwork should be at least 5.-inches thick (actual) and reinforced with No. 4
bars spaced at 18-inches on-center (two directions) and placed on chairs so that the
reinforcement is in the center of the concrete. Contraction joints should be provided
at 8.-feet spacing (maximum). Joints should create square panels where possible. For
rectangular panels (where necessary) the long dimension should be no more than 1.5
times the short dimension. Joint depth should be at least 0.25 times the flatwork
thickness. Expansion joints should be thoroughly sealed to prevent the infiltration of
water into the underlying soils.
Sulfate Content
A representative sample of the on-site soils was submitted for sulfate testing. The
result of the sulfate test is summarized on the Laboratory Test Results, Figure 6. The
sulfate content is consistent with a not applicable sulfate exposure classification per
Table 4.2.1 of the American Concrete Institute Publication 318, consequently, no
special provisions for sulfate resistant concrete are considered necessary. Other
corrosivity testing has not been performed, consequently, on-site soils should be
assumed to be severely corrosive to buried metals unless testing is performed to
indicate otherwise.
Drainage
The following recommendations are intended to minimize the potential adverse
effects of water on the structures and appurtenances.
Consideration should be given to providing the structure with roof gutters and
downspouts that discharge to an area drain system and/or to suitable locations
away from the structure.
All site drainage should be directed away from the structure and not allowed to
flow over slopes.
No landscaping should be allowed against the structure. Moisture accumulation
or watering adjacent to foundations can result in deterioration of building
materials and may affect the performance of foundations.
Irrigated areas should not be over-watered. Irrigation should be limited to that
required to maintain the vegetation. Additionally, automatic systems must be
HETHERUNGTON ENGINEERING, INC.
GEOTECEINICAL INVESTIGATION
Project No. 8787.1
Log No. 20349
March 11, 20t9
Page 11
seasonally adjusted to minimize over-saturation potential particularly in the
winter (rainy) season.
e. All yard and roof drains should be periodically checked to verify they are not
blocked and flow properly, and maintained as necessary.
10. Recommended Observation and Testing During Construction
The following tests and/or observations by the Geotechnical Consultant are
recommended:
Observation and testing during grading.
Observation of foundation excavations prior to placement of forms and
reinforcement.
Utility trench backfill.
Retaining wall backdrains and backfill.
Hardscape/driveway subgrade.
11. Grading and Foundation Plan Review
Grading and foundation plans should be reviewed by the Geotechnical Consultant to
confirm conformance with the recommendations presented herein or to modify the
recommendations as necessary.
LIMITATIONS
The analyses, conclusions and recommendations contained in this report are based on site
conditions as they existed at the time of our investigation and further assume the
excavations to be representative of the subsurface conditions throughout the site. If
different subsurface conditions from those encountered during our exploration are
observed or appear to be present in excavations during construction, the Geotechnical
Consultant should be promptly notified for review and reconsideration of
recommendations.
HETHERINCTON ENGINEERING, INC.
Sincerely,
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GEOTECHNICAL INVESTIGATION
Project No. 8787.1
Log No. 20349
March 11, 2019
Page 12
Our investigation was performed using the degree of care and skill ordinarily exercised,
under similar circumstances, by reputable Geotechnical Consultants practicing in this or
similar localities. No other warranty, express or implied, is made as to the conclusions
and professional advice included in this report.
This opportunity to be of service is sincerely appreciated. If you have any questions,
please call this office.
Boring Logs Figures 4 and 5
Laboratory Test Results Figure 6
Distribution: 5-Addressee
1-via e-mail (elitehomeconstiuction@yahoo.corn)
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REFERENCES
Published
ASCE 7-10, "Minimum Design Loads for Buildings and Other Structures", American
Society of Civil Engineers/Structural Engineers Institute, dated May 2010.
California Geological Survey, "Tsunami Inundation Map for Emergency Planning -
Oceanside Quadrangle/San Luis Rey Quadrangle", California Geological Survey,
June 1, 2009.
ICBO, California Building Code, 2016 Edition.
ICBO, "Maps of Known Active Fault Near-Source Zones in California and Adjacent
Portions of Nevada," California Division of Mines and Geology, 1998.
Peterson, Mark P., et al, "Documentation for the 2008 Update of the United States
National Seismic Hazards Maps," USGS Open File Report 2008-1128, dated 2008.
Structural Engineers Association, Earthquake Hazard Program, Seismic Design Maps
website.
Tan, Siang S. and Kennedy, Michael P., "Geologic Maps of the Northwestern Part of
San Diego County, California," California Division of Mines and Geology, Open-File
Report 96-02, dated 1996.
2007 Working Group and California Earthquake Probability, "The Uniform California
Earthquake Rupture Forecast, Version 2 (UCERF-2)," USGS Open File Report 2007-
1437 and California Geological Survey Special Report 203, dated 2008.
Other (Chronologic)
Geocon, Inc., "Soil and Geologic Investigation Telescope Point, Carlsbad,
California", dated August 1, 1983.
Action Geotechnical Consultants, "Final Compaction and Grading Report for Lots 1 -
5, 56— 65, 117— 139, for Residential Development; Portion of Tract 86-5;...," dated
May 18, 1984.
Action Engineering Consultants, "Addendum for Grading Inspection and Compaction
Report, Dated May 18, 1984", dated June 22, 1984. (Cut Lots 6, 7, 8 should have
been included).
Cooper and Associates, "Grading Plan - Telescope Point, Carlsbad Tract 82-5", dated
As Built July 22, 1996,
Design Travis Deal, "Site Plan, 4615 Telescope Ave., Carlsbad, CA", dated January
2019 (Sheets A-i and A-3).
Project No. 8787.
Log No. 20349
HETHERIMT01Y ENGHEERING, INC.
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B-2 APPROXIMATE LOCATION OF BORING
A A APPROXIMATE LOCATION OF CROSS-SECTION
PLOT PLAN
4615 Telescope Avenue 8 HETHERINGTON ENGINEERING, INC. Carlsbad, California
GEOTECHNICAL CONSULTANTS PROJECT NO. 8787.1 1 FIGURE NO. 2 I
DRILLING COMPANY: Scott's RIG: Hollow Stem Auger DATE: 02/11/19
BORING DIAMETER: 8" DRIVE WEIGHT: 1401b DROP: 30" ELEVATION: ' -t
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co BORING NO. B1
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____
z u cn— SOIL DESCRIPTION
-
- 00 - ______ TERRACE DEPOSITS: Orange brown slightly clayey sand; moist
- to wet, medium dense to dense, well graded -
82/10' 121 9.3
- 50/6" 102 7.5 @3'- Moist, very dense -
5.0 50/5.5" 95 7.5 @5'- Moist, very dense, slightly cemented
10.0—
— 85/11" 111 7.5 @10'- Moist, very dense
15.0—
-
— 83/11" 107 4.8 @15'- Tan, black and orange brown sand; moist, dense —
- 75 107 4.0 @19'- Orange and tan sand; moist, dense
20.0-
Total depth 20-feet
- No seepage -
No caving
25.0---- -
BORING LOG
4615 Telescope Avenue
HETHERINGTON ENGINEERING, INC. Carlsbad, California
PROJECT NO. 8787.1 FIGURE NO. 4 GEOTECHNICAL CONSULTANTS
DRILLING COMPANY: Scott's RIG: Hollow Stem Auger DATE: 02/11/19
BORING DIAMETER: 8" DRIVE WEIGHT: 1401b DROP: 30" ELEVATION: '
>
° ° BORING NO. B..2 I F4
SOIL DESCRIPTION -
- 0.0 TERRACE DEPOSITS: Orange brown slightly clayey to silty sand;
- - moist , dense, well graded
74 112 9.6
-
80/9" 113 6.6 @3'- Moist, medium dense
5.0 @5'- Dark orange brown sand; moist, dense - 82 112 6.0
X
10.0—-71/11" 108 4.8 @10'- Tan, black, and orange brown sand; moist, dense
15.0 75 107 4.3 @15'- Orange and light brown sand; moist, dense
Total depth 16-feet
- No seepage
No caving
20.0-
25.0-----
BORING LOG
4615 Telescope Avenue
HETHERINGTON ENGINEERING, INC. Carlsbad, California
PROJECT NO. 8787.1 FIGURE NO. 5 GEOTECHNICAL CONSULTANTS
. . LABORATORY TEST RESULTS
DIRECT SHEAR
(ASTM: D 3080)
Sample Location Angle of Internal Cohesion Remarks
Friction (°) (psi)
B-i @ 3' 30 100 Undisturbed, soaked, consolidated, drained
SULFATE TEST RESULTS
(Cal Test 417)
Sample Location Soluble Sulfate in Soil (%)
B-i @ ito 5' 0.0530
EXPANSION INDEX
(ASTM: D 4829)
Sample Location Initial Compacted Final Expansion Expansion
Moisture (%) Dry Moisture Index Potential
Density (%)
(pci)
B-i @ ito 5' 9.0 113.6 1 14.8 0 Very low
MAXIMUM DRY DENSITY/OPTIMUM MOISTURE CONTENT
(ASTM: D 1557A)
Sample Location Description Maximum Dry Optimum Moisture
Density (pci) Content (%)
B-i @ 1 to 5' Orange brown silty sand 127.5 10.0
Figure 6
Project No. 8787.1
Log No. 20349