HomeMy WebLinkAboutTR 28214 Geotechnical Evaluation %4#' PETRA SOLID ASA ROCK
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ENGINEERS + GEOLOGISTS + ENVIRONMENTAL SCIENTISTS
February 22, 2016
J.N. 15-527
Mr. Tom Tomlinson
CASTLE & COOKE HOME BUILDING,INC.
4113 Pearl Street
Lake Elsinore, California 92530
Subject: Geotechnical Evaluation for the Lake Street Slope Extension, Eastern Side of Lake
Street Adjacent to the SB I-15 On-Ramp, City of Lake Elsinore, Riverside County,
California
Dear Mr. Tomlinson:
At your request, Petra Geosciences, Inc. (Petra) is presenting geotechnical recommendations for the
proposed eastern descending slope extension along north-bound Lake Street at the on-ramp to Interstate
15 (I-15) in the City of Lake Elsinore, California. The purpose of our evaluation is to provide earthwork
recommendations for the design and construction of the proposed slope, as well as the associated
extension of an existing 30-inch storm drain line. These recommendations are based on our review of
pertinent geotechnical literature, two geotechnical borings, laboratory testing, the requirements of the
2013 California Building Code(CBC), and our engineering judgment and professional opinion.
Brief Site Description
The subject slope area is located along the eastern side of Lake Street at and just south of the intersection
with the southbound 1-15 onramp, as depicted in Figure 1. An existing aggregate facility (WYROC) is
located immediately east and the facilities entrance driveway bounds the subject slope area to the south.
Temescal Wash is located immediately south of the WYROC driveway. The existing east-facing slope
descends at a varying inclination of approximately 2:1 to 3:1 (horizontal:vertical [h:v]) and ranges from
about 10 to 12 feet in height. An existing concrete storm drain inlet pipe is located at the toe of the slope
closer to the I-15 onramp. Other utilities, including overhead power lines, are present along the top of the
slope near the edge of pavement for Lake Street. A wire fence is located close to the Caltrans right-of-
way.
The general slope area has a light amount of vegetation and a few small trees as well as notable amounts
of trash and sotne debris. The toe of slope area has relatively uneven topography and is covered by some
Offices Strategically Positioned Throughout Southern California
RIVERSIDE COUNTY OFFICE
40880 County Center Drive, Suite R,Temecula, CA 92591
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CASTLE & COOKE HOME BUILDING,INC. February 22, 2016
Lake Street at 1-15 On-Ramp/Lake Elsinore J.N. 15-527
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light vegetation, several small to large stockpiles of soil, an erosion control berm, scattered cobbles,
dumped trash and some construction-related debris. Based on our observations and uneven topography,
undocumented artificial fills are presumed to be present. A thicker concentration of trees is located just to
the east.
Proposed Improvements
The proposed 2:1 (h:v) fill slope will extend the existing toe of slope approximately 10 to 15 feet to the
east which will require extending the existing storm drain pipe on the order of 15 feet. Based upon the
KWC Engineers grading exhibit, the proposed top of slope will be approximately two feet lower than the
existing pavement grade and will extend about 10 feet from the existing top of slope to the east. The new
graded slope area will be approximately 175 feet in length and will daylight into existing slopes on the
north and south.
Field Exploration Program
A subsurface exploration program was performed by an engineering geologist from Petra on January 22,
2015. The exploration involved the excavation of two exploratory borings (B-1 and 1 A-1)to a maximum
depth of approximately 21.5 feet below existing grades, utilizing both a track-mounted drill rig equipped
with 8-inch diameter hollow-stem augers and a 3-inch diameter hand-auger. Earth materials encountered
within the exploratory borings were classified and logged by an engineering geologist in accordance with
the visual-manual procedures of the Unified Soil Classification System, ASTM Test Standard D2488.
The approximate locations of the exploratory borings are shown on Figure 2 and logs for the borings are
presented in Appendix A.
Disturbed bulk samples and relatively undisturbed ring samples of in-situ soil materials were collected
from the exploratory borings for classification, laboratory testing and engineering analyses. Undisturbed
samples were obtained using a 3-inch outside diameter modified California split-spoon soil sampler lined
with brass rings. The soil sampler was driven with successive 30-inch drops of a free-fall, 140-pound
automatic trip hammer. The central portions of the driven-core samples were placed in sealed containers
and transported to our laboratory for testing. The number of blows required to drive the split-spoon
sampler for each 6-inch driving increment is noted in the boring logs as Blows per Foot(Appendix A).
Laboratory Testing
The laboratory testing program included the determination of in-situ dry density and moisture content,
maximum dry density and optimum moisture content, remolded shear strength and general corrosion
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potential (sulfate, chloride, pH and minimum resistivity). A description of laboratory test methods and
summaries of the laboratory test data are presented in Appendix B and the in-situ dry density and
moisture content results are presented on the boring logs(Appendix A).
Local Soil Conditions
Based upon subsurface conditions encountered in our borings, shallow undocumented fill is located along
proposed toe-of-slope area which is underlain by natural young alluvial soils. Approximately 1 foot of
fill materials was encountered at Boring B-1 drilled closer to the Caltrans right-of-way area and at least 3
to 4 feet of fill was encountered to the south in HA-1, closer to the WYROC driveway entrance slope. As
noted, several stockpiles of fill soils and scattered cobbles are located along the existing ground surface.
The undocumented fill soils were found to consist of loose to medium dense, slightly moist, silty sand
with gravels, cobbles and some debris. Where encountered, the young alluvium consisted predominantly
of moist, medium dense, clayey sand to an approximate depth of 10 feet below the ground surface, further
underlain by medium dense to occasionally dense alternative sequences of gravelly sands, silty sands and
silts.
Groundwater
Groundwater was not encountered during our exploration activities within this site or the adjacent site to
the west of Lake Street during August 2015 (Petra, 2015) to a maximum explored depth of 21.5 feet
below grade. Groundwater was encountered at depths as shallow as 4 and 4.5 feet below the ground
surface in test pits excavated Geotechnics during 2005 within the site immediately to the west of Lake
Street. Groundwater depths in the Temescal Wash area are expected to vary significantly with seasonal
rainfall events.
CONCLUSIONS AND RECOMMENDATIONS
General
From a geotechnical engineering and engineering geologic point of view, extension of the existing graded
slope is considered suitable provided the following conclusions and recommendations are incorporated
into the design criteria and project specifications.
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Primary Geologic/Geotechnical Considerations
Groundwater and Flooding
Groundwater was not encountered during our exploration activities at this site to a maximum explored
depth of 21.5 feet below grade; however, groundwater was previously reported in test pits excavated just
west of the site area in 2005 at depths as shallow as 4 feet below the ground surface. Groundwater depths
in the Temescal Wash further to the south are expected to vary significantly with seasonal rainfall events.
Groundwater could affect the proposed earthwork conducted during the rainy season.
The site is located near Temescal Wash and is within a Riverside County flood area. The project civil
engineer should evaluate the need for slope protection from erosion cause by scour and flooding.
Landslides and Secondary Seismic Effects
There is no evidence that suggest the site or surrounding area is prone to landsliding. Secondary effects
of seismic activity normally considered as possible hazards to a site include several types of ground
failure. Various general types of ground failures, which might occur as a consequence of severe ground
shaking at the site, include ground subsidence, ground lurching and lateral spreading. Based on the site
conditions, proposed engineered grading and existing site conditions, landsliding and ground subsidence,
or lateral spreading are considered unlikely at the site.
Compressible Soils
The most notable geotechnical factor affecting the project site is the presence of near-surface
compressible soil materials. Such materials consist of existing (undocumented) fill materials and the
upper 1 to 2± feet native alluvium. These surficial soils are not considered suitable for support of the
proposed fill. Accordingly, these materials will require removal to competent alluvial soils and
replacement as properly compacted fill. Removals of compressible soils are estimated to be on the order
of 2 to 4f feet below existing grades as observed in our points of exploration; however, deeper removals
are possible and should be evaluated during earthwork.
EARTHWORK RECOMMENDATIONS
General Earthwork Recommendations
Earthwork should be performed in accordance with the Grading Code of the City of Lake Elsinore, in
addition to the applicable provisions of the 2013 CBC. Grading should also be performed in accordance
with the following site-specific recommendations prepared by Petra based on the proposed construction.
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Geotechnical Observations and Testing
Prior to the start of earthwork, a meeting should be held at the site with the owner, contractor and
geotechnical consultant to discuss the work schedule and geotechnical aspects of the grading. Earthwork,
which will generally entail removal and re-compaction of the near surface soils, should be accomplished
under full-time observation and testing of the geotechnical consultant. A representative of the project
geotechnical consultant should be present onsite during all earthwork operations to document proper
placement and compaction of fills, as well as to document compliance with the other recommendations
presented herein.
Clearing and Grubbing
All existing weeds, grasses, brush, shrubs, trees and similar vegetation existing within areas to be graded
should be stripped and removed from the site. Clearing operations should also include the removal of any
remaining tree rootballs, as well as all existing trash, debris oversized rocks and similar deleterious
materials. Any cavities or excavations created upon removal of existing trees (rootball) or any unknown
subsurface structure(s) should be cleared of loose soil, shaped to provide access for backfilling and
compaction equipment and then backfilled with properly compacted fill. Note that deleterious materials
may be encountered within the site and may need to be removed by hand (i.e. root pickers) during the
grading operations.
The project geotechnical consultant should provide periodic observation and testing services during
clearing and grubbing operations to document compliance with the above recommendations. In addition,
should unusual or adverse soil conditions or buried structures be encountered during grading that are not
described herein, these conditions should be brought to the immediate attention of the project
geotechnical consultant for corrective recommendations.
Excavation Characteristics
The existing site soils should be readily excavatabie with conventional earthmoving equipment. Loose to
medium dense fill soils with gravel/cobbles will likely be encountered within the upper 2 to 3f feet across
the site. Any oversize rocks (i.e., 12-inches in one dimension or greater) encountered should be disposed
of offsite.
Ground Preparation
Existing surficial soils including undocumented fill and the upper portion of native alluvial soils are
considered unsuitable for support of proposed fills. All existing low-density, compressible surficial soils
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in areas to receive compacted fill should be removed to underlying competent alluvial soils as approved
by the project geotechnical consultant.
Based on our observations within our exploratory borings, removals of disturbed and unsuitable surficial
and alluvial soils within the slope area is estimated to be on the order of 3 to 4 feet,but no less than 3 feet
below the proposed toe-of-slope. Unsuitable soil removals may also need to be locally deeper depending
the exposed conditions encountered during grading. The actual depths and horizontal limits of removals
and over-excavations should be evaluated during grading on the basis of observations and testing
performed by the project geotechnical consultant.
Prior to placing engineered fill, all exposed bottom surfaces in the removal areas should be approved by a
representative of project geotechnical consultant and then scarified to a minimum depth of 12-inches,
moisture conditions or dried to achieve optimum moisture conditions and then compacted in-place to a
relative compaction of 90 percent or more.
Suitability of Site Soils as Fill
Site soils are suitable for use in engineered fills provided they are clean from organics and/or debris. Wet
alluvial soils, if encountered during site grading, may require drying back before being reused as fill.
Fill Placement
Fill materials should be placed in approximately 6- to 8-inch thick loose lifts, watered or air-dried as
necessary to achieve optimum moisture condition, and then compacted in-place to a minimum relative
compaction of 90 percent. The laboratory maximum dry density and optimum moisture content for each
change in soil type should be determined in accordance with ASTM D1557.
Benchine
New fills placed against the existing ascending fill slope surface, should be placed on a series of level
benches excavated into or competent native soil materials. These benches should be provided at vertical
intervals of approximately 3 to 4 feet.
Fill Slone Construction
A fill key excavated at a depth of 3 feet or more into competent natural alluvial soils is recommended at
the base of the new fill slope and should be at least equipment-width. To obtain proper compaction to the
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face of fill slopes, the low-height fill slope should be over-filled during construction and then trimmed-
back to the compacted inner core.
The finish surface of the fill slopes should be both grossly and surficially stable to the planned heights at
an inclination of 2:1 (h:v); however, based on the locally granular nature of the soil materials these slopes
may be somewhat erodible.
Cut Slopes
Due to the proposed grading and estimated depth of remedial earthwork, cut slopes will not be created.
Import Soils for Grading
If needed any import soils should be free of deleterious materials, oversize rock and any hazardous
materials. The soils should also be non-expansive and essentially non-corrosive and approved by the
project geotechnical consultant prior to being brought onsite. The geotechnical consultant should inspect
the potential borrow site and conduct testing of the soil at least three days before the commencement of
import operations.
Temporary Excavations
Temporary excavations below existing grades may be required to accommodate the recommended over-
excavation of unsuitable materials. Based on the physical properties of the onsite soils, temporary
excavations which are constructed exceeding 4 feet in height should be cut back to a ratio of 1:1 (h:v) or
flatter for the duration of the over-excavation of unsuitable soil material and replacement as compacted
fill. However, the temporary excavations should be observed by a representative of the project
geotechnical consultant for evidence of potential instability. Depending on the results of these
observations, revised slope configurations may be necessary. Other factors which should be considered
with respect to the stability of the temporary slopes include construction traffic and/or storage of materials
on or near the tops of the slopes, and weather conditions at the time of construction. Applicable
requirements of the California Construction and General Industry Safety Orders, the Occupational Safety
and Health act of 1970 and the Construction Safety Act should also be followed.
General Corrosivity Screening
As a screening level study, limited chemical and electrical tests were performed on representative samples
of onsite soils to identify potential corrosive characteristics of these soils. The following sections present
the test results and an interpretation of current codes and guidelines that are commonly used in our
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industry as they relate to the adverse impact of chemical contents of the site soils and their associated
moisture on various components of the proposed structures in contact with site soils.
A variety of test methods are available to quantify corrosive potential of soils for various elements of
construction materials. Depending on the test procedures adopted, characteristics of the leachate that is
used to extract the target chemicals from the soils and the test equipment; the results can vary appreciably
for different test methods in addition to those caused by variability in soil composition. The testing
procedures referred to herein are considered to be typical for our industry and have been adopted and/or
approved by many public or private agencies. In drawing conclusions from the results of our chemical
and electrical laboratory testing and providing mitigation recommendation to reduce the detrimental
impact of corrosive site soils on various components of the structure in contact with site soils, heavy
references were made to 2013 CBC and American Concrete Institute, 2011 Structural Concrete Building
Code (ACI 318-11). Where relevant information was not available in these codes, references were made
to guidelines developed by California Department of Transportation (Caltrans), mainly because their risk
tolerance for highway bridges are considered comparable to those for residential or commercial structures
and that Post Tensioning Institute(PTI), in part, accepts and uses Caltrans' relevant corrosivity criteria for
post-tensioned slabs on-grade.
It should be noted that Petra does not practice corrosion engineering; therefore, these preliminary test
result and our opinion and engineering judgment provided herein should be considered as general
guidelines only. Additional analyses would be warranted, especially, for cases where buried metallic
building materials (such as copper and cast or ductile iron) in contact with site soils are planned for the
project. In many cases, the project geotechnical engineer is not informed of these choices. Therefore, for
conditions where such elements are considered, we recommend that the project design professionals(i.e.,
the architect and/or structural engineer) consider recommending a qualified corrosion engineer to conduct
additional sampling and testing of near-surface soils during the final stages of site grading to provide a
complete assessment of soil corrosivity. Recommendations to mitigate the detrimental effects of
corrosive soils on buried metallic and other building materials that may be exposed to corrosive soils
should be provided by the corrosion engineer as deemed appropriate.
Concrete in Contact with Site Soils
Soils containing soluble sulfates beyond certain threshold levels as well as acidic soils are considered to
be detrimental to long-term integrity of concrete placed in contact with such soils. For the purpose of this
study, soluble sulfates (SO4) concentration in soils determined in accordance with California Test Method
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No. 417. Soil acidity, as indicated by hydrogen-ion concentration (pH), was determined in accordance
with California Test Method No. 643.
The results of our limited in-house laboratory tests indicate that on-site soils contain a water-soluble
sulfate content 0.0084 percent by weight. Based on Article 1904.1 of Section 1904 of the 2013 CBC,
concrete that will be exposed to sulfates in site soil should be assigned exposure classes in accordance
with the durability requirements of ACI 318.
Based on the test results and in reference to Table 4.2.1 of ACI 318-11, an exposure class of SO is
appropriate for onsite soils. Accordingly, a severity level of Not Applicable for exposure to sulfate may
be expected for concrete placed in contact with the onsite soil materials. As such, Table 4.3.1 of ACI
318-11 provides that no restriction for cement type or maximum water-cement ratio for the fresh concrete
would be required. However, this table indicates that the concrete minimum unconfined compressive
strength should not be less than 2,500 psi.
Further, the results of limited in-house testing of representative samples indicate that soils within the
subject site are neutral with respect to pH (a pH of 7.1). Based on this finding and according to Section
8.22.2 of Caltrans' 2003 Bridge Design Specifications (2003 BDS) requirements (which consider the
combined effects of soluble sulfates and soil pH), a commercially available Type II Modified cement may
be used.
Metals Encased in Concrete
Soils containing a soluble chloride concentration beyond a certain threshold level are considered
corrosive to metallic elements such as reinforcement bars, tendons, cables, bolts, etc. that are encased in
concrete that, in turn, is in contact with such soils. For the purpose of this study, soluble chlorides(Cl) in
soils were determined in accordance with California Test Method No. 422.
Based on Article 1904.1 of Section 1904 of the 2013 CBC, concrete that will be exposed to chlorides
from "deicing chemicals, salt, saltwater, brackish water, seawater or spray from these sources, where
concrete has steel reinforcement" should be assigned exposure classes in accordance with the durability
requirements of ACI 318. According to Table 4.2.1 of ACI 318-11, an exposure class of CO with a
severity designation of Not Applicable is appropriate for reinforced concrete that remains dry or
protected from moisture. Similarly, an exposure class of C1 with a severity designation of Moderate is
appropriate for reinforced concrete that is exposed to moisture but not to external sources of chlorides.
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Based on our understanding of the project, it is our professional opinion that an exposure class of C1 with
a severity designation of Moderate is appropriate for any reinforced concrete, to be placed at the site, that
are in contact with site soils. The results of our limited laboratory tests performed indicate that onsite
soils contain a water-soluble chloride concentration of 60 parts per million (ppm). Article 1904.2 of
Section 1904 of the 2013 CBS requires that concrete mixtures conform to the most restrictive maximum
water-cementitious material ratios, maximum cementitious admixture, minimum air-entrainment and
minimum specified concrete compressive strength requirements of ACI 318 based on the exposure classes
assigned in Article 1904.L No maximum water/cement ratio for the fresh concrete is prescribed by ACI
318 for class C1 (or Moderate severity) exposure condition. However, Table 4.3.1 of ACI 318-
11 indicates that concrete minimum unconfined compressive strength, f should not be less than 2,500
psi.
It should be noted that another source of elevated chloride-ion concentration can be the chloride content
of water that is used to prepare the fresh concrete at the plant. The protection against high chloride
concentration in fresh concrete should therefore be provided by concrete suppliers for the project in
accordance with Table 4.3.1 of ACI 318-11.
Metallic Elements in Contact with Site Soils
Elevated concentrations of soluble salts in soils tend to induce low level electrical currents in metallic
objects in contact with such soils. This process promotes metal corrosion and can lead to distress to
building metallic components that are in contact with site soils. The minimum electrical resistivity
indicates the relative concentration of soluble salts in the soil and, therefore, can be used to estimate soil
corrosivity with regard to metals. For the purpose of this evaluation, the minimum resistivity in soils is
measured in accordance with California Test Method No. 643. The soil corrosion severity rating is
adopted from the Handbook of Corrosion Engineering by Pierre R. Roberge.
The minimum electrical resistivity for onsite soils was found to be 900 ohm-cm based on one test. The
result indicates that on-site soils are Severely Corrosive to ferrous metals. As such, any ferrous metals
that are expected to be placed in direct contact with site soils should be protected against detrimental
effects of severely corrosive soils.
Storm Drain Trench
Utility-trench backfill within the slope should be compacted to a relative compaction of 90 percent or
more. Where onsite soils are utilized as backfill, mechanical compaction should be used. Density testing,
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along with probing, should be performed by the project geotechnical consultant or his representative to
document adequate compaction. Utility-trench sidewalls deeper than about 4 feet should be laid back at a
ratio of 1:1 (h.v) or flatter or shored. A trench box may be used in lieu of shoring. If shoring is
anticipated,the project geotechnical consultant should be contacted to provide design parameters.
Geotechnical Observation and Testing
All aspect construction associated with the slope and storm drain construction should be observed by a
representative of the project geotechnical consultant.
LIMITATIONS
This report is based on the project, as described and the geotechnical data obtained from the field
explorations performed and our laboratory test data. The limited soil materials encountered on the project
site and utilized in our laboratory evaluation are believed representative of the general conditions;
however, soil materials can vary in characteristics between excavations, both laterally and vertically.
Further changes in soils characteristics will take place during rough grading. As such, observation and
testing by Petra during rough grading and construction phases of the project are essential to confirming
the basis of this report. To provide continuity between the design and construction phases, consideration
should be given to retaining Petra for geotechnical construction services. This report should be reviewed
and updated after a period of one year or if the site ownership or project concept changes from that
described herein.
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This opportunity to be of service is sincerely appreciated. If you have any additional questions or
concerns, please feel free contact this office.
Respectfully submitted,
PETRA GEOSCIENCES,INC.
Douglass Johnston CEGI Grayson R. Walker GE
Senior Associate Geologist �S�ONAL OFO Principal Engineer Q?,OFESS/
CEG 2477 ���' �00 GE 871 `�Q�c�ySON R.
4 DOUGLASS L.JOHNST04
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Attachments: Figure I —Site Location Map
Figure 2—Boring Location Map
Appendix A—Boring Logs
Appendix B—Laboratory Test Results
Distribution: (1)Addressee
(1) KWC Engineers, Attn: Mr. Mike Taing(electronic copy)
GRW/DJ/nbc
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REFERENCES
KWC Engineers,2015, Lake Street Sta. 25-27 Interchange Exhibit Option 1.
Morton, D. M., 2004, Preliminary Digital Geologic Map of the Santa Ana 30' x 60' Quadrangle, Southern
California,Version 2.0, ]:100,000 scale, USGS Open-File Report 99-172,sheet 1 of 2.
Petra Geosciences, Inc., 2015, GeotechnicaI Evaluation for the Proposed Berm Adjacent to the S/B 1-15
Lake Street Off-Ramp and Lake Street, Lake Elsinore, Riverside County, California, JN 15-322,
prepared for Castle & Cooke California, Inc., dated September 28.
Riverside County TLMA GIS, 2016:
http://mmc.rivcoit.org/MMC_PubIic/Viewer.html?Viewer=MMC_Public
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PETRA GEOSCIENCES, INC.
40880 County Center Drive,Suite R
Temecula,California 92591
PHONE:(714)549-8921
COSTAMESA TEMECULA SANTACLARITA PALMDESERT
Site Location Map
Lake Street Slope Extension
East Side of Lake St.at 1-15 On-Ramp
City of Lake Elsinore,Riverside County,California
PETRA DATE:February 2016 Figure 1
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N c more than halfoCcoarsc less than S°!°foes GP Paorlygnded gravcLs,gravel sand mixtures, I eorno tines
D fraction is larger than 44 Gravels GM Sit Gravers. Dori dcd vel-sand-silt mixtures
m o 94 sieve wEth fins GC C{ayey Gravels,poorly graded gravel•sxnd-clay mfutures
n SANDS Clean Sandi SW Weil graded sands,gravelly sands,little or no fines
o a c more than bait of coarse (less than 5°!°fines) SP Poorly-graded sands,gravelly sands,lime or no fines
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gravel-clay mixtures
b Inorganic silts&very fine sands,silty or claYY c fine sands,
c=o y SILTS&CLAYS ' clayey silts with slight pinst#city
y.tt `�— Liquid Limit
7 i i; CL Inorganic clays of low to medium plasticity,gravellyclays,
a A � o _ Less Than 50 sandy clays,silty clays,lean clays
E OL Organ o silts&clays orlow plasticity
e z° SILTS&CLAYS Hn Inorganic silts,micaccousordtatomaccnus fine sand orsilt
Z Liquid Limit
Inorganic cFaysofhigh plasticity.
fatclays
Greater1`112n So OH Organfesilts and clays orme-ium-to-high plasticity
Highly Organic Soils P} I Peat,humus Vamp soils with high organic content
Description Sieve Size Grain SizeK Approximate Size
Boulders >12" >12" I erthanbasketball-sized
Cobbles 3-12" 3-12" Fist-sized to basketball-sized
coarse 3/4-3" 314-3" Thumb-sized to fist-sized
Gravel Hne 94-3/4" 0.19-0.75'
Pea-sized to thumb-sized
coarse #10-#4 0.079-(UT' Rock salt-sized to ea-sized
Sand rneditrm #40-#10 0.017-0,079" Sugar-sized to rock salt-sized
one #200-#40 0,0029-0,01T Flour-sized to sugar-sized to
1?' asstn #200 < .0029 Flour-sized and smaller
MAX Maximum Dry Density MA Mechanical(Partical Size)Analysis Trace <l
UP Expansion Potential AT Atterberg Limits Few 1-50/
SO4 Soluble Sulfate Content #200 4200 Screen Wash Some 5-12%
RES Resistivity DSU Direct Shear(Undisturbed Sample) Numerous 12-20%PH Acidity DSR Direct Shcar(Remolded Sample)
CON Consolidation HYD Hydrometer Analysis
SW Swell SE Sand Equivalent
n �,�,'n Ly+�� ��5"-ems*,-x'�'�,et rya ^�,. a�;�•--cYz.
51�
SZ Approximate.Depth of Seepage Can be crushed and granulated by m
Soft hand;"soft like'and structureless
Y Approximate Depth of Standing Groundwater.
Can be grooved with fingernails;
Moderately gouged easily with butter knife;
Hard crumbles under fight hammer blows
Modified California Split Spoon Sample
Standard Penetration Test Cannot break by hand;can be
Hard grooved with a sharp knife;breaks
with a moderate hammer blow
} Bu k Sample
Very Hard Sharp knife leaves setatch;chips I
with repeated hammer blows l
No Recovery in Sampler
Notes;
Brows Per Foot Number of blows inquired to advance sampler I That(unless a lesser distance is sp:dficd). Sarrolers in general wmdriven into the sot or
bedroer at tiae boctnm of tlae hole with a standard(t40 lb.)hammer dropping a standard 30 inches. Drive samples collected in bucket auger borings may be
obtained by doppEng non-standard weight from variable heights. When a SPT sampler is used the blow count conforms to ASTM D-1586
EXPLORATION LOG
Project: Lake Street&South Bound On Ramp to I-15 Boring No.: B-1
Location: Lake Elsinore Elevation: 1,218+/-
Job No.: 15-527 Client: C&C Date: 1/22/16
Drill Method:Hollow-Stern Auger Driving Weight: 140 lbs/30 in Logged By: EPL
W Samples Laboratory Tests
Material Description a Blows oC B Moisture Dry Other
Depth Lith- a Per r I Content Density Lab
(Feet) ology r 6 in. e k (%) (pcl) Tests
ARTIFICIAL FML a CHEM,
Silty Sand(SM):Medium brown;moist;medium dense;One-grained MAX,
sand. SHEAR
ALLUVIUM(gal) 7 <:
Clayey Sand SC :Orangish-brown; moist;medium dense;fine-to 7
medium-grained sand. 9 kr 13.3 84.6
Clayey Sand(SC):Light orangish-brown;slightly moist to moist; :V
medium dense;One-grained sand;w/some rootlets. 12
10
$ Clayey Sand{SG}:Brown;slightly moist;medium dense;fine-to ;�' 7.7 94.8
coarse-grained sand;poorly graded;brittle,locally porous,occasional 10
gravel,w/trace rootlets.
w/less porosity. 5 k.
7 '
9 6.0 98.9
becomes crumbly,slightly moist. 8
6
24 ;x{; 5.6 93.6
Gravelly and to Sandy Gravel(SW-SP):Gray,dry;medium dense; 13
.. ,9 fine-grained sand;friable,poorly to well sorted,angular,w/trace clay. 23
37 2.2 105.5
2 foot layer of coarse gravel.
15 Silty Fine to Coarse Grained Sand to Medium to Coarse Grained Sand 8
SP( /SM):Orangish-brown;dry to slightly moist;medium dense;poorly 10
graded;w/trace of micaceous pores. 13 4.9 103.7
m
a
o 20 Laminated Silt_&Medium to Coarse Grained Sand(MUSH):Brown; 9
moist;medium dense;w/occasional gravel. 13
17 11.4 104.0
Total Depth-21.5'
CL
Caving Occured
No Groundwater Encountered
Boring Backfilled with Cuttings.
c�
0
J
Z
Q PLATE A-1
Petra Geosciences, Inc.
EXPLORATION LOG
Project: Lake Street&South Bound On Ramp to I-15 Boring No.: HA-1
Location: Lake Elsinore Elevation: 1,219+/-
Job No.: 15-527 Client: C&C Date: 1/22/16
Drill Method:Hand Auger Driving Weight: Hand Driven Logged By: EPL
W Samples Laboratory Tests
Material Description t Blows oC B Moisture Dry Other
Depth Lith- e per r I Content Density Lab
(Feet) ology r 6 in. e k M (pef) Tests
ARTIFICIAL FILL (at)
o. Gravelly Sand(SP):Brown;slightly moist;loose;fine-grained sand.
Silty Sand to Clayey Sand(SM/SC):Reddish-brown;moist;loose;
fine-grained sand;w/gravel up to 2"in diameter,clayey fragements,
locally common organics.
Total Depth-2'8"
Practical Refusal on Coblles or Debris
No Groundwater
5 Boring Backfilled with Cuttings.
10
15
a
a 20
0
a
a
N
h
0
O
J
Z
PLATE A-2
13
Petra Geosciences, Inc.
Laboratory Test Criteria
Soil Classification
Soils encountered within the exploratory borings were initially classified in the field in general
accordance with the visual-manual procedures of the Unified Soil Classification System (ASTM D2488).
The samples were re-examined in the laboratory and the classifications reviewed and then revised where
appropriate. The assigned group symbols are presented in the Boring Logs(Appendix A).
In-Situ Moisture and Density
Moisture content and unit dry density of in-place soils were determined in representative strata. Test data
are summarized in the Boring Logs (Appendix A).
Maximum Density/Optimum Moisture
Maximum dry density and optimum moisture content were determined for selected samples of soil in
accordance with ASTM D 1557. Pertinent test values are given on Plate B-1.
Corrosivity
Chemical analyses were performed on selected samples of onsite soil to determine concentrations of
soluble sulfate and chloride, as well as pH and resistivity. These tests were performed in accordance with
California Test Method Nos. 417 (sulfate), 422 (chloride) and 643 (pH and resistivity). Test results are
included on Plate B-1.
Remolded Shear
The Coulomb shear strength parameters, angle of internal friction and cohesion, were determined for a
disturbed (bulk) samples remolded to approximately 90 percent of maximum dry density. These tests
were performed in general accordance with ASTM D3080. Three specimens were prepared for each test.
The test specimens were artificially saturated, and then sheared under varied normal loads at a maximum
constant rate of strain of 0.005 inches per minute. A graph of the test is shown on Plate B-2.
PETRA SOLID AS A ROCK
I
i
i
i
I
i
i
PLATE B-1
LABORATORY MAXIMUM DRY DENSITY
Ogt>otitlp>t � xt>i1�tUC.
0i1' `' 1yoiste Dn`3'Dnsit''.
B-1 0-5' Orangish brown Clayey SAND 12.0 121.0
(1)PER AST D 1557
CORROSION TESTS
Sul.��te� a- Gi>tloride3 �t ResLst�rrity�
B-1 0 0-5' 0.0084 60 7.1 900
(2)PER CALIFORNIA TEST METHOD NO.417
(3)PER CALIFORNIA TEST METHOD NO.422
(4)PER CALIFORNIA TEST METHOD NO.643
PETRA so1�a AS A POCK
4,000
3,500
3,000
0
w
2,500
cr
g 2,000
.l. .i. .�. .}. .�. .}..: .}..
h
.......:...:...:... ...:...:... ......... .
1,500
LU
1,000
;...
J00
OLL-
0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000
NORMAL STRESS-pounds per square foot
SAMPLE DESCRIPTION FRICTION COHESION
LOCATION ANGLE(°) (PSF)
D-i @ 0.0 Reddish Brown Silty Sand(SM) 24 576
PEAK
Reddish Brown Silty Sand(SM)
a m B-I @ 0.0 0.25"DISPLACEMENT 26 408
0
a
NOTES:
V`
J.N. 15-527 February,2016
PETRA GEOSCIENCES,INC. DIRECT SHEAR TEST DATA PLATE B-2
0