site - county of santa barbara
TRANSCRIPT
PROJECT 15-7159
PREPARED BY: PREPARED FOR:
GSI SOILS INC. ERIC VASQUEZ524 EAST CHAPEL STREET VAQUERO ENERGYSANTA MARIA, CA 93454 PETROROCK LLC(805) 349-0140
CAT CANYON, SANTA BARBARA COUNTY
UCCB PRODUCTION PLANTGEOTECHNICAL INVESTIGATION
September 14, 2015SECTION 14 & 23, T9N/R33W
MATERIALS ENGINEERING MATERIALS TESTING GEOTECHNICAL ENGINEERING
SITE
TABLE OF CONTENTS 1.0 INTRODUCTION ............................................................................................................... 1 2.0 PURPOSE AND SCOPE ................................................................................................... 2 3.0 SUBSURFACE SOIL CONDITIONS ................................................................................. 2 4.0 SEISMIC CONSIDERATIONS ........................................................................................... 3
4.1 Seismic Coefficients ............................................................................................ 3 4.2 Liquefaction Analysis .......................................................................................... 3 4.3 Lateral Spreading .................................................................................................. 4 4.4 Slope Stability ....................................................................................................... 4
5.0 CONCLUSIONS AND RECOMMENDATIONS ................................................................. 4
5.1 Clearing and Stripping ........................................................................................ 5 5.2 Site Preparation .................................................................................................... 6 5.3 Structural Fill ........................................................................................................ 7 5.4 Foundations .......................................................................................................... 7 5.5 Reatining Walls .................................................................................................. 11 5.6 Pavement Design ............................................................................................... 13 5.7 Underground Facilities Construction .............................................................. 14 5.8 Surface and Subsurface Drainage ................................................................... 14 5.9 Temporary Excavations and Slopes ................................................................ 16 5.10 Percolation Testing ............................................................................................. 16 5.11 Geotechnical Observation & Testing ............................................................... 17
6.0 LIMITATIONS AND UNIFORMITY OF CONDITIONS .................................................... 18 FIGURES
Site Location Map Site Plan
APPENDIX A
Soil Classification Chart Log of Exploratory Borings
APPENDIX B Moisture-Density Tests
Direct Shear Test R-Value Test
Expansion Index Tests
1
GEOTECHNICAL INVESTIGATION
UCCB PRODUCTION PLANT SECTION 14 & 23, T9N/R33W
CAT CANYON, SANTA BARBARA COUNTY, CA PROJECT 15-7159 1.0
INTRODUCTION
This report presents the results of our geotechnical investigation for the proposed oil production
plant to be constructed at Section 14 & 23, T9N/R33W, north and east of Dominion Road in the
Cat Canyon area of Santa Barbara County, California. A site location map is presented in
Figure 1.
The project site is located approximately 1-1/2 miles east and 1/2-mile north of Dominion Road
and is surrounded by vacant land, oil service roads and agricultural land. The site is relatively
level to slightly sloping with elevations varying from approximately 700 feet above mean sea
level (MSL) on the north side of the property to 720 feet above MSL in the southeast corner. At
the time of our field exploration the site was mostly void of vegetation. Based on available aerial
photographs, the property previously contained oil services equipment, a pond and soil berms.
Grading activities were also evident over the past 10 years.
It is our understanding that construction will include eighteen (18) tanks, heater-treater &
knockout vessels, separators, scrubber towers, oil well pumping units, office & operator
buildings and related facilities. For the purpose of this report, continuous and isolated footing
loads of 3.0 kips per square foot and 100 kips respectively have been assumed.
The project description is based on a site reconnaissance performed by a GSI Soils, Inc.,
engineer and information provided by Vaquero Energy. The plan provided forms the basis for
the "Site Plan", Figure 2.
In the event that there is change in the nature, design or location of improvements, or if the
assumed loads are not consistent with actual design loads, the conclusions and
recommendations contained in this report should be reviewed and modified, if required.
Evaluations of the soils for hydrocarbons or other chemical properties are beyond the scope of
the investigation.
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2.0 PURPOSE AND SCOPE The purpose of this study was to explore and evaluate the surface and subsurface soil
conditions at the site and to develop geotechnical information and design criteria for the
proposed project. The scope of this study included the following items.
1. A review of available soils information for this area of Santa Barbara County.
2. A field study consisting of a site reconnaissance and an exploratory boring
program to formulate a description of the subsurface conditions.
3. A laboratory testing program performed on representative soil samples collected
during our field study.
4. Engineering analysis of the data gathered during our field study, laboratory
testing, and literature review. Development of recommendations for site
preparation and grading, and geotechnical design criteria for foundations.
5. Preparation of this report summarizing our findings, conclusions, and
recommendations regarding the geotechnical aspects of the project site.
3.0 SUBSURFACE SOIL CONDITIONS The near surface soils encountered in our exploratory borings generally consisted of clayey and
silty sands to a depth of 2 to 3 feet. These materials were encountered in a slightly moist state
and in a medium dense condition. Sandy clays were found below the near surface materials to
a depth of 4 to 5 feet. These materials were encountered in a slightly moist to moist state and in
a firm to stiff condition. Clayey sand (hardpan) materials in a very dense condition were found
below the sandy clays.
Ground water was not encountered in our borings. However, very moist soils can be anticipated
at the site in the upper 2 to 4 feet in wet winter months. A more detailed description of the soils
encountered is presented graphically on the "Exploratory Boring Logs", B-1 through B-4,
Appendix A. An explanation of the symbols and descriptions used on the logs are presented on
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the "Soil Classification Chart”.
The soil profile described above is generalized; therefore, the reader is advised to consult the
boring logs (Appendix A) for soil conditions at specific locations. Care should be exercised in
interpolating or extrapolating subsurface conditions between or beyond the borings. On the
boring logs we have indicated the soil type, moisture content, grain size, dry density, and the
applicable Unified Soil Classification System Symbol.
The location of our exploratory borings, shown on Site Plan, Figure 2, was approximately
determined from features at the site. Hence, accuracy can be implied only to the degree that
this method warrants. Surface elevations at the boring locations were not determined.
4.0 SEISMIC CONSIDERATIONS
4.1 The project site was positioned on the USGS Seismic Hazard Maps for a 2%
probability of exceedance in 50 years to determine the maximum considered
earthquake spectral response accelerations. The design seismic parameters are
provided in the following table. A site class D (stiff soils) should be used of
design of the structures.
SEISMIC PARAMETERS Mapped Value
(g) Site Class D Adjusted
Values (g) Design Value
(g) Seismic
Parameter Value (g)
Seismic Parameter
Value (g)
Seismic Parameter
Value (g)
SS 1.071 SMS 1.148 SDS 0.765 S1 0.410 SM1 0.652 SD1 0.435
Latitude, degrees 34.855680 Longitude, degrees -120.322640 Risk Category I/II/III
4.2 Liquefaction Analysis
Liquefaction is described as the sudden loss of soil shear strength due to a rapid
increase of pore water pressures caused by cyclic loading from a seismic event.
In simple terms it means that the soil acts more like a fluid than a solid in a
liquefiable event. In order for liquefaction to occur, the following are generally
needed; granular soils (sand, silty sand and sandy silt), groundwater and low
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density (very loose to medium dense) conditions. A liquefaction study was not
part of our scope for this project, however an opinion can be provided based the
borings performed and on our experience in this area of Santa Barbara County.
Clayey sand (Orcutt sand) soils were predominately encountered in the borings
below a depth of 4 to 5 feet. These soils were in a very dense condition and
would be considered hardpan. In addition, based on our experience in this area,
groundwater depths are anticipated to exceed 50 feet below existing grades.
Based on this information the potential for liquefaction would be negligible.
However, this is a preliminary assessment and a detailed liquefaction study would
be required to fully investigate the potential for liquefaction.
4.3 Lateral Spreading
An estimate of lateral spread displacement to occur at the site was made using
equations developed by Youd, Hansen and Bartlett. The parameters used in the
equation included data from the San Luis Range Fault, average fines content and
a mean grain size. The result of this preliminary analysis indicates lateral
displacements should be minimal. This is primarily due to the site being relatively
level terrain and the lack of liquefiable soil zones.
4.4 Slope Stability
The pad area is located in relatively level terrain. Based on our visual
observations there is no visual evidence of overall slope instability at the site.
The potential for slope movements to influence the proposed construction would
be low to negligible.
5.0 CONCLUSIONS AND RECOMMENDATIONS
1. The site is suitable for the proposed oil production facilities and related
construction provided the recommendations presented in this report are
incorporated into the project plans and specifications.
2. All grading and foundation plans should be reviewed by GSI Soils Inc., hereinafter
described as the Geotechnical Engineer, prior to contract bidding. This review
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should be performed to determine whether the recommendations contained
within this report are incorporated into the project plans and specifications.
3. The Geotechnical Engineer should be notified at least two (2) working days
before site clearing or grading operations commence, and should be present to
observe the stripping of deleterious material and provide consultation to the
Grading Contractor in the field.
4. Field observation and testing during the grading operations should be provided by
the Geotechnical Engineer so that a decision can be formed regarding the
adequacy of the site preparation, the acceptability of fill materials, and the extent
to which the earthwork construction and the degree of compaction comply with
the project geotechnical specifications. Any work related to grading performed
without the full knowledge of, and under direct observation of the Geotechnical
Engineer, may render the recommendations of this report invalid.
5.1 Clearing and Stripping
1. All surface and subsurface deleterious materials should be removed from the
proposed tank battery and disposed of off-site. This includes, but is not limited to
any buried utility lines, loose fills, septic systems, debris, building materials, and
any other surface and subsurface structures. Voids left from site clearing, should
be cleaned and backfilled as recommended for structural fill.
2. Once the site has been cleared, the exposed ground surface should be stripped
to remove surface vegetation and organic soil. The surface may be disced,
rather than stripped, if the organic content of the soil is not more than three
percent by weight. If stripping is required, depths should be determined by a
member of our staff in the field at the time of stripping. Strippings may be either
disposed of off-site or stockpiled for future use in landscape areas if approved by
the landscape architect.
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5.2 Site Preparation
1. The intent of these recommendations is to moisture condition and recompact the
soils in the upper 3 to 4 feet and support the plant equipment foundations on
compacted soil.
2. The equipment (tanks, pumps, vessels, towers, generators & related pads) and
building pad areas should be overexcavated to a depth of three (3) feet below
existing grade or to a depth of 2 feet below the bottom of the deepest footing,
whichever is greater. Due to the potential for fill materials to be encountered, the
final depth of overexcavation would be determined by Geotechnical Engineer at
the time of grading. The exposed surfaces should then be scarified to a depth of
12 inches, wetted to above optimum moisture (1% to 3%) and compacted to at
least ninety (90) percent of maximum dry density (ASTM D1557-02). The native
soils can then be placed and similarly compacted, however, the pad area should
be capped with select import soil such as decomposed granite, Class II/III base or
equivalent. The select import should extend a minimum of 18 inches below finish
pad grade or 1 foot below the bottom of the footings, whichever is deeper. The
lateral limits of excavation, scarification and fill placement should be at least 5
feet beyond the perimeter building and footing lines.
3. If soft or unstable soils are encountered at the bottom of the excavation, these
soft areas should be further excavated (18-inches minimum) and a layer of
stabilization fabric (Mirafi HP370 or equivalent) and Class II/III Base placed prior
to placing fill. The base should be compacted to 90 percent of ASTM D1557.
The removed material can then be replaced and similarly compacted to a
minimum of 90 percent.
4. In order to help minimize potential settlement problems associated with structures
supported on a non-uniform thickness of compacted fill, the soils engineer should
be consulted for specific site recommendations during grading. In general, all
proposed construction should be supported by a uniform thickness of compacted
soil.
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5. The above grading is based on the strength characteristics of the materials under
conditions of normal moisture that would result from rain water and do not take
into consideration the additional activating forces applied by seepage from
springs or subsurface water. Areas of observed seepage should be provided with
subsurface drains to release the hydrostatic pressures.
6. All final grades should be provided with a positive drainage gradient away from
foundations. Final grades should provide for rapid removal of surface water
runoff. Ponding of water should not be allowed on the pads or adjacent to
foundations.
5.3 Structural Fill
1. On-site soils silty sands and clayey sands free of organic and deleterious material
are suitable for use as structural fill. Structural fill should not contain rocks larger
than 3 inches in greatest dimension, and should have no more than 15 percent
larger than 1.5 inches in greatest dimension.
2. Select Import should be free of organic and other deleterious material and should
have a very low expansion potential with a plasticity index of 10 or less and a
sand equivalent greater than 30. Before delivery to the site, a sample of the
proposed import should be tested in our laboratory to determine its suitability for
use as structural fill.
3. Structural fill using on-site inorganic soil or approved import should be placed in
layers, each not exceeding eight inches in thickness before compaction. On-site
inorganic or imported soil should be conditioned with water, or allowed to dry, to
produce a soil water content at approximately optimum value, and should be
compacted to at least 90 percent relative compaction based on ASTM D1557-02.
5.4 Foundations
1. Above ground vessels (heater-treater, knockout & related vessels) should be
supported on individual pad footings (inverted T footings) while buildings can be
located on conventional continuous perimeter footings with concrete slabs-on-
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grade. Pumps, generators and heavy equipment should be supported on
structural mat slabs and tanks should supported on standard AWWA gravel
foundations with a concrete curb or steel ring containment or structural mat slabs.
Pipe racks can be supported on deepened spread footings or shallow drilled
piers.
2. Individual pad footings for vessels should be a minimum of 3 feet wide and
extend the full width or diameter of the vessel and bear a minimum of 2 feet
below lowest adjacent grade. The footings should also be designed with
sufficient mass to minimize the potential for overturning in an earthquake. For
this configuration an allowable dead plus live load bearing pressure of 2500 psf
may be used. For each addition one-foot of footing width and depth the bearing
pressure can be increased by 100 psf and 400 psf respectively up to a maximum
allowable bearing pressure of 4000 psf. Total settlements on the order of 1 to 1.5
inches are anticipated with differential settlements being on the order of 1 inch
over a distance of 50 feet.
3. For lightly loaded buildings, perimeter footings should be at least 12 inches wide
and embedded 18 inches below pad grade or below lowest adjacent finished
grade, whichever is lower. Isolated spread footings should be similarly
embedded and be a minimum of 2 feet square. The reinforcement for the
footings and grade beams should be designed by the structural engineer;
however, a minimum of one (1) No. 5 rebar should be provided both top and
bottom for continuous footings. An allowable dead plus live load bearing
pressure of 2000 psf may be used. Total settlements of less than 1-inch are
anticipated, and differential settlement should be 50 percent of this value.
4. Structural mat slabs may be more appropriate for support of equipment such as
generators, pumps, heavy equipment etc. Mats should be at least 10 to 12
inches thick with a thickened edge extending at least 18 inches below lowest
adjacent grade. The reinforcement for footings and structural mats should be
designed by the structural engineer. A modulus of subgrade reactions (Kv) of 150
pci can be used. An allowable dead plus live load bearing pressure of 2500 psf
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may be used. Total settlements on the order of 1-inch are anticipated with
differential settlements being 50 percent of this value over 30 feet.
5. Tanks can also be supported on structural mat slabs (see recommendations
above) where total settlements of less than 1-inch are desired. Alternatively, the
tanks could be supported on a minimum 12-inch leveling and drainage course of
open graded, 1-inch by No. 4 crushed rock on the compacted tank pad. The
crushed rock should be increased to a minimum thickness of 24 inches at the
perimeter of the tank pad. This thickened section should be a minimum of 5 feet
inside the tank perimeter and extend 5 feet beyond the perimeter. The transition
from 1 to 2 feet should be made on a slope of 1½ horizontal to 1 vertical. The
crushed rock should be compacted to 95 percent of the maximum dry density as
determined by ASTM D1557. The rock outside the tank should be contained by a
concrete curb or steel ring with weep holes to facilitate drainage. Total
settlements on the order of 1 to 1-1/2 inches should be anticipated with
differential settlements being in the range of ½ to 3/4 inches depending on the
height and diameter of the tank. The tank pads should be graded with a crown of
at least ½ to 1 inch at the center of the tank to compensate for greater settlement
anticipated near the center and to ultimately provide sufficient slope for cleaning
of the tank.
6. Pipe racks and related equipment could be supported on piers drilled into the
underlying competent clayey sands. The piers should extend a minimum of 3 feet
into competent materials approved by the geotechnical engineer. Minimum pier
depths of 6 to 7 feet should be anticipated. However, depths of 10+ feet should
be anticipated if the disturbed fill or native soils are encountered. In addition, the
structural engineer should determine the actual depth based on vertical, lateral
and uplift loads. To accommodate for variability in the materials and to adjust the
pier lengths accordingly, a representative of GSI Soils should be continuously on-
site to monitor drilling, rebar placement and concrete placement.
7. Drilled piers should have a minimum diameter of 18 inches. Allowable bearing
capacity and skin friction values of 3000 psf and 500 psf may be used for
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downward loads in competent native materials or engineered fill. For uplift loads
a skin friction value of 300 psf and the foundation weight may be used. Skin
friction should be neglected in the upper native soils (3 to 4 feet) for both
downward and uplift loads. Concrete should have a minimum compressive
strength of 3,000 psi or as specified by the Project Structural Engineer. A higher
concrete compressive strength may be required for structural considerations. For
concrete placed in dry excavations a 4 to 6-inch slump would be appropriate. For
concrete placed by the tremie method a 7 to 9-inch slump is recommended. The
shaft(s) should contain steel reinforcement as determined by the Project
Structural Engineer in accordance with applicable UBC or ACI Standards.
8. Alternatively, deepened footings could be used to support the pipe racks. These
footings should extend a minimum of 2 feet into competent native soils or
engineered fill. The excavations should be approved by the geotechnical
engineer, penetrate through the upper disturbed soils and have a minimum
overall depth of 4 feet below existing grades. The footing should be at least 2
feet square and 36 inches thick. An allowable bearing pressure of 2500 psf could
be used with a one-third increase for short term wind and seismic loads
9. Allowable bearing capacities may be increased by one-third (⅓) when transient
loads such as winds or seismicity are included.
10. During foundation construction, care should be taken to minimize evaporation of
water from excavations. Foundation excavations should be observed by this firm
prior to the placing of reinforcing steel or concrete. Concrete should be placed
only in excavations that have been kept moist, are free of cracks and contain no
loose or soft soil or debris.
11. Lateral forces on structures may be resisted by passive pressure acting against
the sides of shallow footings and/or friction between the soil and the bottom of the
footing. For resistance to lateral loads, a friction factor of 0.35 may be utilized for
sliding resistance at the base of the spread footings in undisturbed native
materials or engineered fill. A passive resistance of 350 pcf equivalent fluid
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weight may be used against the side of shallow footings. If friction and passive
pressures are combined, the lesser value should be reduced by 33 percent.
5.5 Retaining Walls
1. Retaining walls should be designed to resist lateral pressures from adjacent soils
and surcharge loads applied behind the walls (see Table below).
Lateral Pressure and Condition (Compacted Fill)
Equivalent Fluid Pressure, pcf
Unrestrained Wall
Rigidly Supported
Wall
Active Case, Drained
Level-native soils 45 --
Level-granular backfill 30 --
At-Rest Case, Drained
Level-native soils -- 65
Level-sand backfill 50
Passive Case, Drained
Level 2:1 Sloping Down
350 200 --
For sloping backfill add 1 pcf for every 2 deg. (Active case) and 1.5 pcf for every 2 deg. (At-rest case)
2. Isolated retaining wall foundations should extend a minimum depth of 24 inches
below lowest adjacent grade. An allowable toe pressure of 2,500 psf is
recommended for footings supported on 12 inches of soils compacted to 90%. A
coefficient of friction of 0.35 may be used between subgrade soil and concrete
footings. If friction and passive pressures are combined, the lesser value should
be reduced by 33%.
3. For retaining walls greater than 6 feet, as measured from the top of the
foundation, a seismic horizontal surcharge of 10H² (pounds per linear foot of wall)
may be assumed to act on retaining walls. The surcharge will act at a height of
0.6H above the wall base (where H is the height of the wall in feet). This
surcharge force shall be added to an active design equivalent fluid pressure of 45
pounds per square foot of depth for the seismic condition.
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4. In addition to the lateral soil pressure given above, the retaining walls should be
designed to support any design live load, such as from vehicle and construction
surcharges, etc., to be supported by the wall backfill. If construction vehicles are
required to operate within 10 feet of a wall, supplemental pressures will be
induced and should be taken into account through design.
5. The above-recommended pressures are based on the assumption that sufficient
subsurface drainage will be provided behind the walls to prevent the build-up of
hydrostatic pressure. To achieve this we recommend that a filter material be
placed behind all proposed walls. The blanket of filter material should be a
minimum of 12 inches thick (wrapped in Mirafi 140n or eq.) and should extend
from the bottom of the wall to within 12 inches of the ground surface. The top 12
inches should consist of water conditioned, compacted, native soil. A 4-inch
diameter drain pipe should be installed near the bottom of the filter blanket with
perforations facing down. The drain pipe should be underlain by at least 4 inches
of filter type material. Adequate gradients should be provided to discharge water
that collects behind the retaining wall to an adequately controlled discharge
system with suitably projected outlets. The filter material should conform to Class
I, Type B permeable material as specified in Section 68 of the California
Department of Transportation Standard Specifications, current edition. A typical
1" x #4 concrete coarse aggregate mix approximates this specification.
6. For hydrostatic loading conditions (i.e. no free drainage behind retaining wall), an
additional loading of 45 pcf equivalent fluid weight should be added to the above
soil pressures. If it is necessary to design retaining structures for submerged
conditions, allowed bearing and passive pressures should be reduced by 50
percent. In addition, soil friction beneath the base of the foundations should be
neglected.
7. Precautions should be taken to ensure that heavy compaction equipment is not
used immediately adjacent to walls, so as to prevent undue pressure against, and
movement of, the walls.
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5.6 Pavement Design
1. The table below provides pavement sections based on an estimated R-Value of
25 for the near surface silty sand soils encountered at the site.
RECOMMENDED MINIMUM ASPHALT CONCRETE PAVEMENT SECTIONS DESIGN THICKNESS
T.I. A.C.-in. A.B.-in.
4.5
2.5
6.0
5.0
2.5
7.5
5.5
3.0
8.5
6.0
3.0
9.5
T.I. = A.C. =
A.B. =
Traffic Index Asphaltic Concrete - must meet specifications for Caltrans Type A Asphalt Concrete Aggregate Base - must meet specifications for Caltrans Class II Aggregate Base (R-Value = minimum 78) *All-weather roads should conform to the requirements for ¾” maximum Class II Base with increased binder. The amount passing the #30 and #200 sieves should vary between 15 to 30 and 7 to 11 percent respectively.
2. All-weather roads should have a minimum section of 12 inches of Class II Base
with sufficient binder as indicated in the table. The upper 12 inches of subgrade
for all-weather sections should be compacted to a minimum relative compaction
of 95 percent based on ASTM D1557-02 and should be crowned for good
drainage.
3. R-value samples should be obtained and tested at the completion of rough
grading and the pavement sections confirmed or revised. All asphaltic concrete
pavement sections and all sections should be crowned for good drainage. All
asphalt pavement construction and materials used should conform with Sections
26 and 39 of the latest edition of the Standard Specifications, State of California,
Department of Transportation. Aggregate bases and sub-bases should also be
compacted to a minimum relative compaction of 95 percent based ASTM D1557-
02.
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5.7 Underground Facilities Construction
1. The attention of contractors, particularly the underground contractors, should be
drawn to the State of California Construction Safety Orders for "Excavations,
Trenches, Earthwork". Trenches or excavations greater than 5 feet in depth
should be shored or sloped back in accordance with OSHA Regulations prior to
entry.
2. For purposes of this section of the report, bedding is defined as material placed in
a trench up to 1 foot above a utility pipe and backfill is all material placed in the
trench above the bedding. Unless concrete bedding is required around utility
pipes, free-draining sand should be used as bedding. Sand proposed for use as
bedding should be tested in our laboratory to verify its suitability and to measure
its compaction characteristics. Sand bedding should be compacted by
mechanical means to achieve at least 90 percent relative compaction based on
ASTM Test D1557-02.
3. On-site inorganic soil, or approved import, may be used as utility trench backfill.
Proper compaction of trench backfill will be necessary under and adjacent to
structural fill, building foundations, concrete slabs and vehicle pavements. In
these areas, backfill should be conditioned with water (or allowed to dry), to
produce a soil water content of about 2 to 3 percent above the optimum value
and placed in horizontal layers each not exceeding 8 inches in thickness before
compaction. Each layer should be compacted to at least 90 percent relative
compaction based on ASTM Test D1557-02. The top lift of trench backfill under
vehicle pavements should be compacted to the requirements given in report
section 5.3 for vehicle pavement subgrades. Trench walls must be kept moist
prior to and during backfill placement
5.8 Surface and Subsurface Drainage
1. Concentrated surface water runoff within or immediately adjacent to the site
should be conveyed in pipes or in lined channels to discharge areas that are
relatively level or that are adequately protected against erosion.
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2. Surface drainage gradients should be planned to prevent ponding and promote
drainage of surface water away from foundations and edges of pavements. For
soil areas we recommend that a minimum of five (5) percent gradient be
maintained.
3. Careful attention should be paid to erosion protection of soil surfaces adjacent to
the edges of roads, and in other areas where "hard" edges of structures may
cause concentrated flow of surface water runoff. Erosion resistant matting such
as Miramat, or other similar products, may be considered for lining drainage
channels.
4. The on-site soils are susceptible to erosion. Erosion control measures that could
be considered include.
a. Construction of lined interceptor ditches or diversion dikes above fill slopes.
Construction of slope drains to safely direct concentrations of surface water
runoff to a more suitable location downslope.
b. Hydroseeding or planting a surface cover of protective vegetation on all
surfaces. In addition, an erosion control blanket should be placed over the
slopes to protect the vegetation while it becomes established. For permanent
erosion protection the berms should be lined with lean mix concrete or
suitable fabric such as North American Green C350 or equivalent.
5. It should be expected that, even with the construction of carefully planned and
designed erosion control measures, some erosion will occur during the first few
wet seasons after the project is completed. Site grading should be inspected,
particularly after heavy, prolonged rainfall, to identify erosion areas at an early
stage. Maintenance work should be done as soon as practical to repair these
areas and prevent their enlargement.
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5.9 Temporary Excavations and Slopes
1. Conventional earth moving equipment should be adequate to excavate the soils
at the site.
2. We recommend that temporary excavations in the surface clays (greater than 5
feet deep) be sloped at an inclination of 1.5:1 (horizontal:vertical). The actual
temporary slope to be constructed should be observed by the geotechnical
engineer during excavation. During the rainy season, or where soft or loose
sediments, or perched water conditions are found, flatter slopes are more likely.
3. It should be noted that it is the Contractor's responsibility to maintain safe cut
slopes based on actual field conditions and according to OSHA requirements.
The slopes presented are those we expect will be used in project design and we
have assumed that in general the slopes will not be open for more than 2 to 3
days. In some geologic units, perched water may be present locally. The stability
of the slopes may be compromised somewhat where these conditions exist due
to softening or piping of the saturated materials.
4. Where the temporary trench slopes are inclined as described above, no shoring
is required. However, where adjacent features may influence establishment of
appropriate slopes, the Contractor may elect to use shoring and retain the slopes
with a tie back system. In no case should personnel enter trenches with vertical
sidewalls greater than 5 feet deep without proper shoring. Design and installation
of the shoring should be the responsibility of the Contractor and should be
performed according to OSHA requirements.
5.10 Percolation Study
1. Shallow percolation borings (P-1 through P-3) were drilled to assess the
absorption rates of the underlying soil at a depth of 4 to 5 feet below grade for the
proposed leach field. Silty sands and sandy clays were encountered at the
locations drilled. The percolation tests were conducted in general conformance
with U.S. Department of Health, Education and Welfare Manual of Septic Tank
Practice Guidelines. The results are summarized in the following table.
September 14, 2015 Project 15-7159
17
Test No.
Depth (feet)
Soil Description
Percolation Rate
P-1 4 Sandy Clay (CL) 45 min/in
P-2 4 Sandy Clay (CL) 43 min/in
P-3 4 Silty Sand (SM) 12 min/in
5.11 Geotechnical Observation and Testing
1) Field exploration and site reconnaissance provides only a limited view of the
geotechnical conditions of the site. Substantially more information will be
revealed during the excavation and grading phases of the construction.
Stripping & clearing of vegetation, overexcavation, scarification, fill and backfill
placement and compaction should be reviewed by the geotechnical
professional during construction to evaluate if the materials encountered during
construction are consistent with those assumed for this report.
2) Special inspection of grading should be provided in accordance with California
Building Code Section 1705.6 and Table 1705.6. The special inspector should
be under the direction of the engineer. As indicated in the table below periodic
inspection should suffice for this project.
CBC TABLE 1705.6 REQUIRED VERIFICATION AND INSPECTION OF SOILS
VERIFICATION AND INSPECTION TASK CONTINUOUS DURING TASK LISTED
PERIODIC DURING TASK LISTED
1. Verify materials below shallow foundations are adequate to achieve the design bearing capacity
X
2. Verify excavations are extended to proper depth and have reached proper material
X
3. Perform classification and testing of compacted fill
X
4. Verify use of proper materials, densities and lift thicknesses during placement and compaction of compacted fill
X
5. Prior to placement of compacted fill, observe subgrade and verify that site has been prepared properly.
X
September 14, 2015 Project 15-7159
18
3) The validity of the recommendations contained in this report are also dependent
upon a prescribed testing and observation program. Our firm assumes no
responsibility for construction compliance with these design concepts and
recommendations unless we have been retained to perform on-site testing and
review during all phases of site preparation, grading, and foundation/slab
construction. The Geotechnical Engineer should be notified at least two (2)
working days before site clearing or grading operations commence to develop a
program of quality control.
6.0 LIMITATIONS AND UNIFORMITY OF CONDITIONS
1. It should be noted that it is the responsibility of the owner or his/her
representative to notify GSI Soils Inc. a minimum of 48 hours before any
stripping, grading, or foundation excavations can commence at this site.
2. The recommendations of this report are based upon the assumption that the soil
conditions do not deviate from those disclosed during our study. Should any
variations or undesirable conditions be encountered during grading of the site,
GSI Soils Inc. will provide supplemental recommendations as dictated by the
field conditions.
3. This report is issued with the understanding that it is the responsibility of the
owner or his/her representative to ensure that the information and
recommendations contained herein are brought to the attention of the architect
and engineer for the project, and incorporated into the project plans and
specifications. The owner or his/her representative is responsible for ensuring
that the necessary steps are taken to see that the contractor and subcontractors
carry out such recommendations in the field.
4. As of the present date, the findings of this report are valid for the property studied.
With the passage of time, changes in the conditions of a property can occur
whether they be due to natural processes or to the works of man on this or
adjacent properties. Legislation or the broadening of knowledge may result in
changes in applicable standards. Changes outside of our control may find this
September 14, 2015 Project 15-7159
19
report to be invalid, wholly or partially. Therefore, this report should not be relied
upon after a period of three (3) years without our review nor is it applicable for any
properties other than those studied.
5. Validity of the recommendations contained in this report is also dependent upon
the prescribed testing and observation program during the site preparation and
construction phases. Our firm assumes no responsibility for construction
compliance with these design concepts and recommendations unless we have
been retained to perform continuous on-site testing and review during all phases
of site preparation, grading, and foundation/slab construction.
Thank you for the opportunity to have been of service in preparing this report. If you have any
questions or require additional assistance, please feel free to contact the undersigned at (805)
349-0140.
Sincerely,
GSI SOILS INC.
Rick Armero Ronald J. Church Project Manager GE #2184
Figure No.
115-7159
Project No.
UCCB PRODUCTION PLANTSECTION 14 & 23, T9N/R33W
SITE MAP
CAT CANYON, SANTA BARBARA COUNTY
SITE
Figure No.
215-7159
Project No.
UCCB PRODUCTION PLANTSECTION 14 & 23, T9N/R33W
SITE PLAN
CAT CANYON, SANTA BARBARA COUNTY
Boring Location
B-2
B-1
B-3
B-4
P-2 P-3
P-1
September 14, 2015 Project 15-7159
FIELD INVESTIGATION
Test Hole Drilling The field investigation was conducted on August 28, 2015. Four (4) exploratory borings were
drilled at the approximate locations indicated on the Site Plan, Figure 2. The locations of the
borings were approximated in the field.
Undisturbed and bulk samples were obtained at various depths during test hole drilling. The
undisturbed samples were obtained by driving a 2.4-inch inside diameter sampler into soils.
Bulk samples were also obtained during drilling.
Logs of Boring A continuous log of soils, as encountered in the borings was recorded at the time of the field
investigation, by a Staff Engineer. The Exploration Boring Logs are attached.
Locations and depth of sampling, in-situ soil dry densities and moisture contents are tabulated in
the Boring Logs.
UNIFIED SOIL CLASSIFICATION SYSTEMSMAJOR DIVISION PLASTICITY CHART
GW USED FOR CLASSIFICATION OF FINE GRAINED SOILSGP
GM
GC
SW
SP
SM
SC
ML
CL
OL
MH
CH
OH
HIGHLY ORGANIC CLAYS Pt
SAMPLE DRIVING RECORDBLOWS PER FOOT
2550/7"Ref/3"
NOTE: TO AVOID DAMAGE TO SAMPLING TOOLS, DRIVING IS LIMITED TO 50 BLOWS PER 6 INCHES DURING OR AFTER SEATING INTERVAL
KEY TO TEST DATABag Sample CONS Consolidation (ASTM D2435)
Drive, No Sample Collected DS Cons. Drained Direct Shear (ASTM D3080)
2 1/2" O.D. Mod. California Sampler, Not Tested PP Pocket Penetrometer
2 1/2" O.D. Mod. California Sampler, Tested GSD Grain Size Distribution (ASTM D422)
Standard Penetration Test CP Compaction Test (ASTM D1557)
Sample Attempted with No Recovery EI Expansion Index (ASTM D4829)
Water Level at Time of Drilling LL Liquid Limit (in percent)
Water Level after Drilling PI Plasticity Index
PROJECT NO.:
DATE DRILLED:
FIGURE NO.
A-1UCCB PRODUCTION PLANT
CAT CANYON, SANTA BARBARA COUNTY
15-71598/28/2015 AND BORING LOG LEGEND
POORLY GRADED SANDS, GRAVELLY SANDS
SILTY SANDS, POORLY GRADED SAND-SILT MIXTURES
CLAYEY SANDS, POORLY GRADED SAND-CLAY MIXTURES
WELL GRADED GRAVELS, GRAVEL-SAND MIXTURES
POORLY GRADED GRAVELS, GRAVEL-SAND MIXTURES
SILTY GRAVELS, POORLY GRADED GRAVEL-SAND-SILT MIXTURES
CLAYEY GRAVELS, POORLY GRADED GRAVEL-SAND-CLAY MIXTURES
SYMBOLS TYPICAL NAMES
FINECOARSE
INORGANIC CLAYS OF HIGH PLASTICITY, FAT CLAYS
ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY, ORGANIC SILTS
PEAT AND OTHER HIGHLY ORGANIC SOILS
INORGANIC SILTS, SILTY OR CLAYEY FINE SANDS, OR CLAYEY SILTS WITH SLIGHT PLASTICITY
INORGANIC CLAYS OF LOW TO MEDIUM PLASTICITY, GRAVELLY, SANDY, OR SILTY CLAYS, LEAN CLAYS
WELL GRADED SANDS, GRAVELLY SANDS
DESCRIPTION
INORGANIC SILTS , MICACEOUS OR DIATOMACIOUS FINE SANDY OR SILTY SOILS, ELASTIC SILTS
50 BLOWS DROVE SAMPLER 3 INCHES DURING OR AFTER INITIAL 6 INCHES OF SEATING
COARSE MEDIUM FINE
25 BLOWS DROVE SAMPLER 12 INCHES, AFTER INITIAL 6 INCHES OF SEATING
50 BLOWS DROVE SAMPLER 7 INCHES, AFTER INITIAL 6 INCHES OF SEATING
OVER 32
SOIL GRAIN SIZE
ORGANIC CLAYS AND ORGANIC SILTY CLAYS OF LOW PLASTICITY
SOIL CLASSIFICATION CHART
2 - 4
4 - 8
8 - 16
16 - 32
HARD
0 - 1/4
OVER 4
FIRM
STIFF
VERY STIFF
1/2 - 1
1 - 2
2 - 4
BLOWS/FOOT
RELATIVE DENSITY
VERY LOOSE 0 - 2
RELATIVE DENSITY
LOOSE
VERY SOFT
SOFT
STRENGTHSANDS, GRAVELS, AND NON PLASTIC SILTS
BLOWS/FOOT
0 - 4
4 - 10
CLAYS AND PLASTIC SILTS
1/4 - 1/2
10 - 30
30 - 50
OVER 50
MEDIUM DENSE
DENSE
VERY DENSE
FIN
E G
RA
INE
D S
OIL
S O
ver 5
0% <
#20
0 si
eve
GRAVELS Over 50% > #4 sieve
CO
AR
SE
GR
AIN
ED
SO
ILS
Ove
r 50%
> #
200
siev
e
SANDS Over 50% < #4 sieve
SILTS AND CLAYS Liquid limit < 50
SILTS AND CLAYS Liquid limit > 50
CLEAN GRAVELS WITH LITTLE OR NO FINES
GRAVELS WITH OVER 12% FINES
CLEAN SANDS WITH LITTLE OR NO FINES
SANDS WITH OVER 12% FINES
60 40 20 0 80 100 120 0
20
40
60
80
A-LINE
MH & OH
CL
CH
ML & OL
LIQUID LIMIT
PLAS
TIC
ITY
IND
EX
B
BOULDERS COBBLES GRAVEL SAND
SILT CLAY
U.S. STANDARD SIEVE
SOIL GRAIN SIZE IN MILLIMETERS
150 75 19 4.75 2.0 0.425 0.075 0.002
6" 3" 3/4" 4 10 40 200
JM DRILL RIG:
716'E
LEV
ATI
ON
(FT)
DE
PTH
(FT)
GR
AP
HIC
LO
G
SOIL
TYP
E
SA
MP
LE
CO
NV
. SP
T B
LOW
CO
UN
T
WA
TER
C
ON
TEN
T (%
)
DR
Y D
EN
SIT
Y
(PC
F)
LIQ
UID
LIM
IT
PLA
SIT
. IN
DE
X
UN
C. C
OM
P.
STR
EN
GTH
(PS
F)
16.3
29 10.1
57 7.8
5.9
50/6" 8.4
9.3
EXPLORATORY BORING LOGS
UCCB PRODUCTION PLANTSANTA BARBARA COUNTY, CALIFORNIA
PROJECT NO. DATE FIGURE NO.15-7159 September-15 A-2
696 20
697 19
698 18
699 17
700 16
701 15
702 14
703 13
704 12
705 11
706 10
707 9
708 8
709 7
710 6
711 5
712 4
713 3
714 2
715 1
GROUNDWATER DEPTH (FT):
GEOTECHNICAL DESCRIPTION COMMENTS AND ADDITIONAL TESTS
LOGGED BY: Simco 2400 BORING NO.: B-1
ELEVATION: BORING DIAMETER (INCH): 5 DATE DRILLED: 28 August 2015
Sandy Clay: brown, moist, fine to medium grained, trace gravel, firm to very stiff
CL
B
B
Boring terminated at 15 feet
Clayey Sand: brown, moist, fine to medium grained, some silt & gravel, dense to very dense (hardpan)
SC
very dense
B
B
SC- SM
Clayey Silty Sand: light brown, slightly moist, fine to medium grained, some gravel, medium dense
JM DRILL RIG:
716'E
LEV
ATI
ON
(FT)
DE
PTH
(FT)
GR
AP
HIC
LO
G
SOIL
TYP
E
SA
MP
LE
CO
NV
. SP
T B
LOW
CO
UN
T
WA
TER
C
ON
TEN
T (%
)
DR
Y D
EN
SIT
Y
(PC
F)
LIQ
UID
LIM
IT
PLA
SIT
. IN
DE
X
UN
C. C
OM
P.
STR
EN
GTH
(PS
F)
22 18.3
50/6" 10.4
LOGGED BY: Simco 2400 BORING NO.: B-2
ELEVATION: BORING DIAMETER (INCH): 5 DATE DRILLED: 28 August 2015
GROUNDWATER DEPTH (FT):
GEOTECHNICAL DESCRIPTION COMMENTS AND ADDITIONAL TESTS
715 1
714 2
713 3
712 4
711 5
710 6
709 7
708 8
707 9
706 10
705 11
704 12
703 13
15
702 14
700 16
701
699 17
698 18
697 19
696 20
EXPLORATORY BORING LOGS
UCCB PRODUCTION PLANTSANTA BARBARA COUNTY, CALIFORNIA
PROJECT NO. DATE FIGURE NO.15-7159 September-15 A-3
Sandy Clay: brown, moist, fine to medium grained, trace gravel, firm to very stiff
CL
B
Boring terminated at 6 feet
Clayey Sand: brown, moist, fine to medium grained, some silt & gravel, very dense (hardpan)
SC
Clayey Silty Sand: light brown, slightly moist, fine to medium grained, some gravel, medium dense
SC- SM
JM DRILL RIG:
712'E
LEV
ATI
ON
(FT)
DE
PTH
(FT)
GR
AP
HIC
LO
G
SOIL
TYP
E
SA
MP
LE
CO
NV
. SP
T B
LOW
CO
UN
T
WA
TER
C
ON
TEN
T (%
)
DR
Y D
EN
SIT
Y
(PC
F)
LIQ
UID
LIM
IT
PLA
SIT
. IN
DE
X
UN
C. C
OM
P.
STR
EN
GTH
(PS
F)
19.2
13.2
LOGGED BY: Hand Auger BORING NO.: B-3
ELEVATION: BORING DIAMETER (INCH): 4 DATE DRILLED: 28 August 2015
GROUNDWATER DEPTH (FT):
GEOTECHNICAL DESCRIPTION COMMENTS AND ADDITIONAL TESTS
711 1
710 2
709 3
708 4
707 5
706 6
705 7
704 8
703 9
702 10
701 11
700 12
699 13
15
698 14
696 16
697
695 17
694 18
693 19
692 20
EXPLORATORY BORING LOGS
UCCB PRODUCTION PLANTSANTA BARBARA COUNTY, CALIFORNIA
PROJECT NO. DATE FIGURE NO.15-7159 September-15 A-4
Sandy Clay: brown, moist, fine to medium grained, trace gravel, firm to very stiff
CL
B
Boring terminated at 5.5 feet
Clayey Sand: brown, moist, fine to medium grained, some silt & gravel, dense to very dense (hardpan)
SC- CL
Clayey Silty Sand: light brown, slightly moist, fine to medium grained, some gravel, medium dense
SC- SM
B
B
JM DRILL RIG:
705'E
LEV
ATI
ON
(FT)
DE
PTH
(FT)
GR
AP
HIC
LO
G
SOIL
TYP
E
SA
MP
LE
CO
NV
. SP
T B
LOW
CO
UN
T
WA
TER
C
ON
TEN
T (%
)
DR
Y D
EN
SIT
Y
(PC
F)
LIQ
UID
LIM
IT
PLA
SIT
. IN
DE
X
UN
C. C
OM
P.
STR
EN
GTH
(PS
F)
17.3
50/4" 15.9
LOGGED BY: Simco 2400 BORING NO.: B-4
ELEVATION: BORING DIAMETER (INCH): 5 DATE DRILLED: 28 August 2015
GROUNDWATER DEPTH (FT):
GEOTECHNICAL DESCRIPTION COMMENTS AND ADDITIONAL TESTS
704 1
703 2
702 3
701 4
700 5
hard
699 6
698 7
697 8
696 9
695 10
694 11
693 12
692 13
15
691 14
689 16
690
688 17
687 18
686 19
685 20
EXPLORATORY BORING LOGS
UCCB PRODUCTION PLANTSANTA BARBARA COUNTY, CALIFORNIA
PROJECT NO. DATE FIGURE NO.15-7159 September-15 A-5
Sandy Clay: brown, moist, fine to medium grained, trace gravel, firm to very stiff
CL
B
Boring terminated at 6.0 feet
Silty Sand: light brown, slightly moist, fine to medium grained, some gravel, trace to some clay, medium dense
SM- SC
B
JM DRILL RIG:
712'E
LEV
ATI
ON
(FT)
DE
PTH
(FT)
GR
AP
HIC
LO
G
SOIL
TYP
E
SA
MP
LE
CO
NV
. SP
T B
LOW
CO
UN
T
WA
TER
C
ON
TEN
T (%
)
DR
Y D
EN
SIT
Y
(PC
F)
LIQ
UID
LIM
IT
PLA
SIT
. IN
DE
X
UN
C. C
OM
P.
STR
EN
GTH
(PS
F)
17.3
28 August 2015
P-1 & 2LOGGED BY: Hand Auger BORING NO.:
ELEVATION: BORING DIAMETER (INCH): 4 DATE DRILLED:
GROUNDWATER DEPTH (FT):
GEOTECHNICAL DESCRIPTION COMMENTS AND ADDITIONAL TESTS
711 1
710 2
709 3
708 4
707 5
706 6
705 7
704 8
703 9
702 10
701 11
700 12
699 13
15
698 14
696 16
697
695 17
694 18
693 19
692 20
EXPLORATORY BORING LOGS
UCCB PRODUCTION PLANTSANTA BARBARA COUNTY, CALIFORNIA
PROJECT NO. DATE FIGURE NO.15-7159 September-15 A-6
Sandy Clay: brown, slightly moist, fine to medium grained, trace gravel, firm to stiff
CL
B
Boring terminated at 4.0 feet
Silty Sand: light brown, slightly moist, fine to medium grained, some gravel, trace to some clay, medium dense
SM- SC
B
JM DRILL RIG:
712'E
LEV
ATI
ON
(FT)
DE
PTH
(FT)
GR
AP
HIC
LO
G
SOIL
TYP
E
SA
MP
LE
CO
NV
. SP
T B
LOW
CO
UN
T
WA
TER
C
ON
TEN
T (%
)
DR
Y D
EN
SIT
Y
(PC
F)
LIQ
UID
LIM
IT
PLA
SIT
. IN
DE
X
UN
C. C
OM
P.
STR
EN
GTH
(PS
F)
5.8
LOGGED BY: Hand Auger BORING NO.: P-3
ELEVATION: BORING DIAMETER (INCH): 5 DATE DRILLED: 28 August 2015
GROUNDWATER DEPTH (FT):
GEOTECHNICAL DESCRIPTION COMMENTS AND ADDITIONAL TESTS
711 1
710 2
709 3
708 4
707 5
706 6
705 7
704 8
703 9
702 10
701 11
700 12
699 13
15
698 14
696 16
697
695 17
694 18
693 19
692 20
EXPLORATORY BORING LOGS
UCCB PRODUCTION PLANTSANTA BARBARA COUNTY, CALIFORNIA
PROJECT NO. DATE FIGURE NO.15-7159 September-15 A-7
B
Boring terminated at 4.0 feet
Silty Sand: light brown, slightly moist, fine to medium grained, some gravel, trace to some clay, medium dense
SM- SC
B
September 14, 2015 Project 15-7159
LABORATORY TESTING
Moisture-Density Tests
The field moisture content, as a percentage of the dry weight of the soil, was determined by
weighing samples before and after oven drying. Dry densities, in pounds per cubic foot, were
also determined for the undisturbed samples. Results of these determinations are shown in the
Exploration Drill Hole Logs.
Direct Shear Test
Direct shear tests were performed on undisturbed samples, to determine strength characteristics
of the soil. The test specimens were soaked prior to testing. Results of the shear strength tests
are attached.
Resistance (R) Value Test
An R-Value was estimated based on the gradation and plasticity index of a bulk sample obtained
from boring B-4. The results indicate that the silty sand soils have an R-Value of at least 25.
Expansion Index Tests
Expansion indices of 0 and 36 were obtained for the near surface silty sands and underlying
sandy clays, respectively. The test procedure was performed in accordance with ASTM D4829.
Project: Project No.
Sample Location: Initial Dry Density (pcf)
Soil Description: Initial Moisture (%)
Sample Type: Peak Shear AngleCohesion (psf)
DIRECT SHEAR TEST
ASTM D3080-11 (Modified for unconsolidated-undrained conditions)
310
10.1
98.4
26
B-1 @ 3 Feet
Sandy Clay
UCCB PRODUCTION PLANT 15-7159
0
1000
2000
3000
4000
0 1000 2000 3000 4000
Shea
r Str
ess,
psf
Normal Stress, psf
Shear Strength Diagram
Remolded
Ring