HomeMy WebLinkAboutCT 15-08; GEOTECHNICAL INVESTIGATION; 2020-08-10Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Carlsbad, California MTGL Log No. 19-2317
GEOTECHNICAL INVESTIGATION
Sheraton Hotel 6
5420 Grand Pacific Drive
Carlsbad, California
Prepared For:
Grand Pacific Carlsbad Hotel L.P.
5900 Pasteur Court, Suite 200
Carlsbad, California 92008
Prepared By:
MTGL, Inc.
6295 Ferris Square, Suite C
San Diego, California 92121
February 6, 2020
Revised August 10, 2020
MTGL Project No. 1916A16
MTGL Log No. 19-2317 RECEIVED
AUG 27 2020
LAND DEVELOPMENT
ENGINEERING
Geo technical Engineering
Construction Inspection
Materials Testing
Environmental
OFFICE LOCATIONS
ORANGE COUNTY
CORPORATE Bamcx
2992 E. La Palma Avenue
Suite A
Anaheim, CA 92806
Tel: 714.632.2999
Fax: 714.632.2974
February 6, 2020
Revised August 10, 2020
Grand Pacific Carlsbad Hotel L.P.
5900 Pasteur Court, Suite 200
Carlsbad, California 92008
Attention: Mr. Houston Arnold
MTGL Project No. 1916A16
MTGL Log No. 19-2317
www.mtglinc.com
Subject: GEOTECHNICAL INVESTIGATION
Sheraton Hotel 6
5420 Grand Pacific Drive, Carlsbad, California
Dear Mr. Arnold:
In accordance with your request and authorization, we have completed a geotechnical
investigation for the subject site. MTGL, Inc. (MTGL) performed a geotechnical investigation that
included the proposed Sheraton Hotel 6 site in 2015 (Appendix A, References). The site was
graded during grading for the Marbrisa Phase Ill development, which included the adjacent pool
house to the west and the existing Sheraton resort to the south. Existing fill was removed, along
with an expansive clay layer underlying the site. The Phase Ill grading occurred from about March
2016 to February 2017.
We are pleased to present the following report which addresses both engineering geologic and
geotechnical conditions including a description of the site conditions, results of our field
exploration and laboratory testing, and our conclusions and recommendations for grading and
foundations design.
Based on our investigation, the site will be suitable for construction, provided the
recommendations presented herein are incorporated Into the plans and specifications for the
proposed construction. Details related to geologic conditions, seismicity, site preparation,
foundation design, and construction considerations are also included in the subsequent sections
of this report.
We appreciate this opportunity to be of continued service and look forward to providing
additional consulting services during the planning and construction of the project. Should you
have any questions regarding this report, please do not hesitate to contact us at your
convenience.
SAN DIEGO
IMPERIAL COUNTY
6295 Ferris Square
Suite C
San Diego, CA 92121
Tel: 858.537.3999
Fax: 858.537.3990
INlAND EMPIRE
14467 Meridian Parkway
Building 2A
Riverside, CA 92518
Tel: 951.653.4999
Fax: 951.653.4666
OC/LA/INLAND EMPIRE
DISPATch
800.491.2990
SAN DIEGO DISPATCH
888.844.5060
Respectfully submitted,
MTGL, Inc.
ep en J.00vr,R.c.E.,G.E '
Vice President I Chief Engineer
Sheraton Hotel 6- Geotechnical Investigation MTGL Project No. 1916A16
Carlsbad, California MTGL Log No. 19-2317
TABLE OF CONTENTS
2.00 INTRODUCTION ................................................................................................................................................. 3
1.01 PLANNED CONSTRUCTION .......................................................................•..........................................................3
1.02 SCOPE OF WORK.. .............- ......................................................
1.03 SITE DESCRIPTION ..............................................................................................................................................3
1.04 FIELD INVESTIGATION ...... .. ......................... . ..................................... ................
.
..................................................... 3
1.05 LABORATORY TESTING ........................................................................................................................................4
2.00 FINDINGS ........................................................................................................................................................... 4
2.01 REGIONAL GEOLOGIC CONDITIONS . ...................................................................................................................4
2.02 SITE GEOLOGIC CONDITIONS ........... . .............................................. ........................................................................... 4
2.03 GROUNDWATER CONDITIONS ....................................................................................................................... 5
2.04 FAULTING AND SEISMICITY ...................................................................................................................................5
2.05 LIQUEFACTION POTENTIAL....................................................................................................................................5
2.06 LANDSLIDES .......................................................................................................................................................5
2.07 TSUNAMI AND SEICHE HAZARD.............................................................................................................................5
3.00 CONCLUSIONS .......................................................6
.-
3.01 GENERAL CONCLUSIONS .... .... ........ ...................
....6
3.02 EARTHQUAKE ACCELERATIONS I CBC SEISMIC PARAMETERS ...................................................................................6
3.03 EXPANSION POTENTIAL ......... . ................... .................................... ...................... . ................................................. 7
4.00 RECOMMENDATIONS ....................................................................................................................................... 7
4.01 EXCAVATION CHARACTERISTICS/SHRINKAGE. .......................................................................................................... 7
4.02 SETTLEMENT CONSIDERATIONS ............................................................................................................................7
4.03 SITE CLEARING RECOMMENDATIONS .......................................... . ......................................................... . ................. 7
4.04 SITE GRADING RECOMMENDATIONS-STRUCTURES AND HARDSCAPE ...................................................8
405 COMPACTION REQUIREMENTS 8
4.06 FILL MATERIALS.................................................................................................................................................8
4.07 SLOPES ............ .. ............................................................................................................................................... 8
4.09 FOUNDATIONS...................................................................................................................................................8
4.09 CONCRETE SLABS ON GRADE AND MISCELLANEOUS FLATWORK.................................................................................9
4.10 CORROSIVI1Y ........................... ................................................. .. ............................................... ...................... 10
4.11 RETAINING WALLS ... ................................................................................................................... ...................... 10
4.12 FOUNDATION SETBACKS ........................... . .......... . .......................................... 11
4.13 BID RETENTION BASIN .................................. .11
4.14 CONSTRUCTION CONSIDERATIONS ......... .. ........................................................................................................... 11
4.14.1 MOISTURE SENSITIVE SOILS/WEATHER RELATED CONCERNS.................................................................................11
4.14.2 DRAINAGE AND GROUNDWATER CONSIDERATIONS..............................................................................................11
4.14.3 TEMPORARY EXCAVATIONS AND SHORING .......................................................................... . ................. .............. 12
4.14.4 UTILITY TRENCHES .................................. ......... . ........................................... .................................................. 13
4.14.5 SITE DRAINAGE .............................................................................................................................................14
4.15 GEOTECHNICAL OBSERVATION/TESTING OF EARTHWORK OPERATIONS....................................................................14
5.00 LIMITATIONS ........................................................ .......................................................................................... 14
ATTACHMENTS:
Figure 1 - Vicinity Map
Figure 2- Boring Location Plan
Figure 3-Subsurface Profile
Figure 4- Retaining Walt Drainage Detail
Appendix A - References
Appendix B - Field Exploration Program
Appendix C - Laboratory Test Procedures
Appendix D - Seismicity
Appendix E - Standard Earthwork and Grading Specifications
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Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
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1.00 INTRODUCTION
In accordance with your request and authorization, MTGL, Inc. has completed a Geotechnical Investigation for the
subject site. The following report presents a summary of our findings, conclusions and recommendations based
on our investigation, laboratory testing, and engineering analysis.
1.01 Planned Construction
We understand that a four-story hotel building is planned to be constructed in the northeast portion of the parcel
currently developed with the Sheraton Carlsbad Resort and Spa. The new hotel will have a curved footprint, with
the south end directly north of the existing hotel and the building curving north and west. The existing swimming
pool and restroom building lie to the west of the proposed development. The site has been sheet-graded; grading
for the new development will be minimal. We understand the new building will be founded on a slab on grade;
no subsurface spaces are planned.
The hotel building pad is anticipated to have a finished pad grade elevation of 223.55 feet, with a floor elevation
of 224.30 feet. Other improvements at the site, including sidewalks and retaining walls are already in place.
1.02 Scope of Work
The scope of our geotechnical services included the following:
Review of geologic, seismic, ground water and geotechnical literature (Appendix A).
Logging, sampling and backfilling of four exploratory borings drilled with a 6-inch diameter hollow-stem
auger, truck-mounted drill rig to a maximum depth of 41.5 feet below existing grades. Appendix B
presents a summary of the field exploration program.
Laboratory testing of representative samples (See Appendix Q.
Geotechnical engineering review of data and engineering recommendations.
Preparation of this report summarizing our findings and presenting our conclusions and recommendations
for the proposed construction.
1.03 Site Description
The project is located at 5420 Grand Pacific Drive, Carlsbad, California, see Vicinity Map, Figure 1. The site Is bare
dirt surface lot, with a storm water collection basin in the northern portion. Retaining walls border the building
pad on the north and east. The Boring Location Plan, Figure 2, shows the proposed development area.
The site was previously graded after 2015 as part of the development of the adjacent resort hotel, with retaining
walls along the north and east sides built to contain the fill forming the building pad. The area is relatively flat with
an elevation of approximately 223 to 224 feet above mean sea level (msl).
104 Field Investigation
Prior to the field investigation, an engineer from our office performed a site reconnaissance by to mark the borings,
as shown on the Site Plan, and to evaluate the boring locations with respect to obvious subsurface structures and
access for the drilling rig. Underground Service Alert was then notified of the marked location for utility clearance.
Our subsurface investigation consisted of drilling test borings using a truck-mounted drill rig equipped with a 6-
inch diameter hollow stem auger. See Appendix B for further discussion of the field exploration including logs of
test borings.
Borings were logged and sampled using Modified California Ring (Ring) and Standard Penetration Test (SPT)
samplers at selected depth intervals. Samplers were driven into the bottom of the boring with successive drops of
a 140-pound weight falling 30 inches. Blows required driving the last 12 inches of the 18-inch Ring and SPT
samplers are shown on the boring logs in the "blows/foot" column (Appendix B). SPT was performed in the borings
in general accordance with the American Standard Testing Method (ASTM) D1586 Standard Test Method.
Representative bulk soil samples were also obtained from our borings and test pits.
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Carlsbad, California MTGL Loa No. 19-2317
Each soil sample collected was inspected and described in general conformance with the Unified Soil Classification
System (USCS). The soil descriptions were entered on the boring logs. All samples were sealed and packaged for
transportation to our laboratory.
1.05 Laboratory Testing
Laboratory tests were performed on representative samples to verify the field classification of the recovered
samples and to determine the geotechnical properties of the subsurface materials. All laboratory tests were
performed in general conformance with ASTM or State of California Standard Methods. The results of our moisture
content and dry density laboratory tests are presented on the boring togs. The results of the other laboratory tests
are presented in Appendix C of this report.
2.00 FINDINGS
2.01 Regional Geologic Conditions
The site Is located in the coastal portion of the Peninsular Range Province of California. This area of the Peninsular
Range Province has undergone several episodes of marine inundation and subsequent marine regression
throughout the last 54 million years, which has resulted in the deposition of a thick sequence of marine and
nonmarine sedimentary rocks on the basement rock of the Southern California Batholith. Gradual emergence of
the region from the sea occurred in Pleistocene time, and numerous wave-cut platforms, most of which were
covered by relatively thin marine and nonmarine terrace deposits, formed as the sea receded from the land.
Accelerated fluvial erosion during periods of heavy rainfall, coupled with the lowering of the base sea level during
Quaternary times, resulted in the rolling hills, mesas, and deeply Incised canyons which characterize the landforms
in the general site vicinity today.
2.02 Site Geologic. Conditions
As observed during this investigation, and our review of geotechnical maps, the site is underlain at depth by
Quaternary-aged Old Paralic Deposits. Previously placed engineered fill materials were encountered above the
formational materials. Logs of the subsurface conditions encountered in our borings are provided in Appendix B.
Generalized descriptions of the materials encountered during this investigation are presented below.
Previously placed fill soils were encountered in the borings and extended up to approximately twelve (12) feet
below existing grade. As observed in our borings, the fill materials consisted of reddish-brown silty sand (SM) that
was fine to medium grained, moist, and medium dense to dense. At some locations, the fill contained chunks of
silty fat (plastic) clay. The borings performed for this current study did not encounter the fat plastic Santiago
Formation claystone encountered in the explorations performed in 2015. Only scattered chunks of the fat plastic
clay were encountered in the fill presently overlying the site, indicating the claystone was removed during the
mass grading of the property performed after our 2015 study.
In general, the fill soils are considered suitable for support of the proposed loading, however, moderate remedial
grading is recommended to provide uniform support conditions and repair any disturbed areas developed after
the site was graded following our 2015 study. Recommendations are presented in this report for remedial grading
of existing fill materials.
Quaternary-aged Old Paralic Deposits were encountered in the borings at depths that ranged from about twelve
to fifteen feet below existing grade. As observed in our explorations, the Old Paralic Deposits consisted of silty
sandstone 'SM', poorly graded sandstone with silt 'SP-SM' and poorly graded sandstone 'SP'. Colors ranged from
reddish brown, tan, light brown, yellowish brown, and light gray. The sandy materials were fine to medium
grained, moist, dense to very dense and friable. In general, the Old Paralic Deposits are considered suitable for
support.of structural loading in their current condition.
A subsurface profile of materials encountered in our explorations is presented in Figure 3
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2.03 Groundwater Conditions
Groundwater was not encountered in the borings drilled for this investigation. Based on the relative density of
the formational materials at the site there is a high potential for perched water to appear along the contact
between the fill soils and the formational materials. Excessive irrigation, or changes in rainfall or site drainage
could produce seepage or locally perched groundwater conditions within the soil underlying the site.
2.04 Faulting and Seismicity
Active earthquake faults are very significant geologic hazards to development in California. Active faults are those
which have undergone displacement within the last approximately 11,000 years. Potentially active faults show
evidence of displacement within the last approximately 1.6 million years. The site is not located within an Alquist-
Priolo Earthquake Fault Zone and there are no known active faults mapped through the site, therefore, surface
rupture of an active fault is not considered to be a significant geologic hazard at the site.
Potential seismic hazards at the site are anticipated to be the result of ground shaking from seismic events on
distant active faults. The nearest known active fault is the Rose Canyon fault zone, which is located about 5.0 miles
west of the site. A number of other significant faults also occur in the San Diego metropolitan area suggesting that
the regional faulting pattern is very complex. Faults such as those offshore are known to be active and any could
cause a damaging earthquake. Other active faults within the region include the Coronado Banks fault zone,
approximately 21.0 miles southwest of the site, and the Elsinore fault zone, approximately 22.6 miles northeast of
the site. The San Diego metropolitan area has experienced some major earthquakes in the past and will likely
experience future major earthquakes. A summary of faults and associated properties is presented in Appendix D.
Based on its proximity to the Rose Canyon Fault, the site should be considered a "near fault site" as defined in
ASCE 7-16.
2.05 Liquefaction Potential
Liquefaction is a phenomenon where earthquake induced ground vibrations increase the pore pressure in
saturated, granular soils until it is equal to the confining, overburden pressure. When this occurs, the soil can
completely lose its shear strength and become liquefied. The possibility of liquefaction is dependent upon grain
size, relative density, confining pressure, saturation of the soils, and strength of the ground motion and duration
of ground shaking. In order for liquefaction to occur three criteria must be met: underlying loose, coarse-grained
(sandy) soils, a groundwater depth of less than about 50 feet and a nearby large magnitude earthquake. Given
the relatively dense nature of the subsurface soils, and the absence of a groundwater table, the potential for
liquefaction at the site Is considered to be negligible.
2.06 Landslides
Evidence of ancient landslides was not found at the subject site. Recommendations are provided in the following
sections of the report which will help to reduce the potential for future slope instabilities.
2.07 Tsunami and Seiche Hazard
The site is not located within an area mapped by the California Geological Survey as subject to inundation by
tsunami. Given the location of the site at an elevation of approximately over 200 feet msl (mean sea level), the
inundation hazard posed by tsunami is considered to be low. Seiches are not considered to be a hazard due the
absence of above-ground tanks or reservoirs located immediately up-gradient from the site.
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3.00 CONCLUSIONS
3.01 General Conclusions
Given the findings of the investigation, it appears that the site geology is suitable for the proposed construction.
Based on the investigation, in our opinion that the proposed development is safe against landslides and settlement
provided the recommendations presented in our report are incorporated into the design and construction of the
project. Grading and construction of the proposed project will not adversely affect the geologic stability of
adjacent properties. The nature and extent of the investigation conducted for the purposes of this declaration are,
in our opinion, in conformance with generally accepted practice in this area. Therefore, the proposed project
appears to be feasible from a geologic standpoint. There appears to be no significant geologic constraint onsite
that cannot be mitigated by proper planning, design, and sound construction practices. Specific conclusions
pertaining to geologic conditions are summarized below:
Due to proximity of the site to regional active and potentially active faults, the site could experience
moderate to high levels of ground shaking from regional seismic events within the projected life of the
building. A design performed in accordance with the current California Building Code and the seismic
design parameters of the Structural Engineers Association of California is expected to satisfactorily
mitigate the effects of future ground shaking.
The potential for active (on-site) faulting is considered low.
a The potential for liquefaction during strong ground motion is considered low.
The potential for landslides to occur is considered low if the remedial recommendations presented herein
are incorporated.
The on-site fill materials are considered suitable for structural support if moderate remedial grading is
performed. Recommendations are presented in the following sections for remedial grading at the site.
The proposed structures may be supported by a conventional shallow foundation system if the existing
fill materials are mitigated as recommended.
3.02 Earthquake Accelerations / CBC Seismic Parameters
The 2019 California Building Code seismic design parameters were obtained from the USGS website (ASCE 7-16
design code) using a project location of latitude 33.133° North and a longitude of 117.3110 West. Based upon
the anticipated grading requirements at the site a Site Class C was used for the project. The seismic design
parameters are presented below: IIon-1 Ss 1.049
Si 0.377g
Site Class C
SMS 1.248g
SMI 0.556g
SDS 0.832g
SD1 0.377g
Seismic Design Category D
Risk Category Ill
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3.03 Expansion Potential
While not encountered in our investigation, there is a potential for highly expansive claystone zones to be
encountered in the existing fill materials covering the site. These claystone materials, encountered as scattered
chunks incorporated into the existing fill covering the site, apparently were mixed into the fill. We understand
remedial grading consisting of removal of Santiago Formation claystone was performed prior to our current study.
Our expansion index testing indicated the expansion potential of the fill that contained chunks of the fat claystone
was low. This indicated the presence of the clay chunks, in the concentrations encountered in the fill, to not be
seriously detrimental. Accordingly, our recommendations are based on assuming low expansion potential
materials underlie the foundations and slabs. However, if zones of fat clay materials are encountered in
excavations for foundations and utilities, they should be removed and replaced with materials not containing the
clay chunks. The clay chunks are not considered suitable for support of any new loads.
4.00 RECOMMENDATIONS
Our recommendations are considered minimum and may be superseded by more conservative requirements of
the architect, structural engineer, building code, or governing agencies. The foundation recommendations are
based on the expansion index and shear strength of the onsite soils. Import soils, if necessary should have a very
low expansion potential (Expansion Index less than 20) and should be approved by the Geotechnical Engineer prior
to importing to the site. In addition to the recommendations in this section, additional general earthwork and
grading specifications are Included in Appendix E.
4.01 Excavation Characteristics/Shrinkage
Our exploratory borings were advanced with little difficulty within the fill soils and no oversize materials were
encountered in our subsurface investigation. Our exploratory borings were advanced with minimal effort within
the friable formational materials encountered for our current study. Accordingly, we expect that all earth
materials will be excavatable with conventional heavy-duty grading equipment with experienced operators and
that oversized materials are not expected.
Shrinkage is the decrease in volume of soil upon removal and re-compaction expressed as a percentage of the
original in-place volume, which will account for changes in earth volumes that will occur during grading. Bulking
is the increase in volume of soil upon removal re-compaction expressed as a percentage of the original in-place
volume. Our estimate for shrinkage of the onsite fill soils are expected to range from 5 to 10 percent. Our estimate
for bulking of the formational materials is estimated to range from 5 to 10 percent. Bulking and shrinkage potential
can vary considerably based on the variability of the in-situ densities of the materials in question.
4.02 Settlement Considerations
Based on the proposed grading recommendations, we anticipate that properly designed and constructed
foundations that are supported on compacted fill materials will experience a total static settlement of up to 1.0
inch with differential settlements of Y2 an inch. As a minimum, structures supported by shallow conventional
foundations should be designed to accommodate a total settlement of at least 1.0 inch with differential
settlements of 36 an inch over a horizontal distance of 40 feet.
4.03 Site Clearing Recommendations
All surface vegetation, trash, debris, asphalt concrete, portland cement concrete and underground pipes and
existing bioflltratlon swales should be cleared and removed from the proposed construction site. From review of
a preliminary site plan (Appendix A, References), we understand existing sewer laterals beneath the site will be
relocated. An existing sidewalk along the west side of the site will remain in place. Depressions resulting site
clearing should be backfilled with properly compacted material. All organics, debris, trash and topsoil should be
removed from the grading area and hauled offsite.
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4.04 Site Grading Recommendations -Structures and hardscape
Remedial grading for the new building at the site should include over-excavation and removal of a minimum of
two (2) feet of previously placed fills beneath floor slab areas and below the bottoms of footings and replacement
with properly compacted material. Remedial grading beneath exterior hardscape should include over-excavation
and removal of one (1) foot of existing fill material, with replacement with properly compacted material. The
bottom of the removals should then be evaluated by the geotechnical consultant to see if further remedial grading
is warranted. The horizontal limits of the removals should extend to at least 5 feet beyond the building footprint.
As described previously, it may be necessary to remove zones of fat plastic clay, if encountered during remedial
grading of foundation, floor slab and hardscape areas. If encountered at the bottoms of the recommended
removal depths, an additional one foot of over-excavation should be performed. The fat clay materials should be
wasted off-site.
Prior to fill placement, the exposed excavation bottom should be scarified to a depth of 8 to 12 inches, moisture
conditioned and re-compacted. The materials should be compacted to at least 90 percent of the maximum dry
density as determined by ASTM Test Method D1557 at a moisture content that is optimum to slightly above
optimum moisture content.
4.05 Compaction Requirements
All fill materials should be compacted to at least 90 percent of maximum dry density as determined by ASTM Test
Method D1557. Fill materials should be placed in loose lifts, no greater than 8 inches prior to applying compactive
effort. All engineered fill materials should be moisture-conditioned and processed as necessary to achieve a
uniform moisture content that is optimum to slightly above optimum moisture content and within moisture limits
required to achieve adequate bonding between lifts.
4.06 Fill Materials
Removed or over-excavated soils may be reused as engineered fill except for fat clay soils and soils containing
detrimental amounts of organic material, trash and other debris.
Imported materials should be free from vegetable matter and other deleterious substances, not contain rocks or
lumps of a greater dimension than 3 inches, have an expansion index of less than 20, and be approved by the
geotechnical consultant. Soils of poor gradation, expansion, or strength properties shall be removed off-site.
4.07 Slopes
We understand grading at the site will not likely include construction of permanent slopes. If grading plans change,
we can provide additional recommendations for construction of permanent slopes.
4.09 Foundations
The recommendations and design criteria are "minimum" in keeping with the current standard-of-practice. They
do not preclude more restrictive criteria by the governing agency or structural considerations. The project
structural engineer should evaluate the foundation configurations and reinforcement requirements for actual
structural loadings. The foundation design parameters assume that remedial grading is conducted as
recommended in this report, and that all the buildings are underlain by a relatively uniform depth of compacted
fill with a low expansion potential (Expansion Index less than 50).
Conventional shallow foundations are considered suitable for support of the proposed structure provided that
remedial grading to treat existing fill materials is performed. The remediated fill soils are considered to be suitable
embedment materials for foundations. The Old Paralic formational materials are also considered suitable
embedment materials for foundations.
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Allowable Soil Bearing: 3,000 lbs/ft2 (allow a one-third increase for short-term wind or seismic
loads). The allowable soil bearing may be increase 500 lbs/ft2 for every
12-inch increase in depth above the minimum footing depth and 250
lbs/ft2 for every 12-inch increase in width above the minimum footing
width. The bearing value may not exceed 5,000 lbs/ft2
Minimum Footing Width: 24 inches
Minimum Footing Depth: 24 inches below lowest adjacent soil grade
Coefficient of Friction: 0.35
Passive Pressure: 350 psf per foot of depth. Passive pressure and the friction of resistance
could be combined without reduction.
We recommend a minimum reinforcement for footings of two No. 5 bars placed within three inches of the top of
footings and two No. 5 bars placed within three inches of the bottom of footings. However, footing reinforcement
is within the purview of the structural engineer, who may require
heavier reinforcement.
4.09 Concrete Slabs on Grade and Miscellaneous Flatwork
Interior slab-on-grade should be designed for the actual applied loading conditions expected. The structural
engineer should size and reinforce slabs to support the expected loads using accepted methods of concrete design,
such as those provided by the Portland Cement Association or the American Concrete Institute. A modulus of
subgrade reaction of 150 pounds per cubic inch (pci) may be used in design. Based on geotechnical consideration,
interior slab for conventional slab-on-grade design should be a minimum of 5 inches thick and should be reinforced
with at least No. 3 bars on 18 centers, each way. Actual reinforcement should be designed by the project structural
engineer based upon low expansion potential. Structural slabs should be designed by the structural engineer and
should span from foundation supports.
Concrete slabs constructed on soil ultimately cause the moisture content to rise in the underlying soil. This results
from continued capillary rise and the termination of normal evapotranspiration. Because normal concrete is
permeable, the moisture will eventually penetrate the slab. Excessive moisture may cause mildewed carpets,
lifting or discoloration of floor tiles, or similar problems. To decrease the likelihood of problems related to damp
slabs, suitable moisture protection measures should be used where moisture sensitive floor coverings, moisture
sensitive equipment, or other factors warrant.
A commonly used moisture protection in southern California consists of about 2 inches of clean sand covered by
at least 10 mil plastic sheeting. In addition, 2 inches of clean sand are placed over the plastic to decrease concrete
curing problems associated with placing concrete directly on an impermeable membrane. However, it has been
our experience that such systems will transmit from approximately 6 to 12 pounds of moisture per 1,000 square
feet per day. This may be excessive for some applications, particularly for sheet vinyl, wood flooring, vinyl tiles,
or carpeting with impermeable backing that use water soluble adhesives. Considering the expected use of
moisture-sensitive floor coverings for the project, we recommend use of a Stego Wrap moisture barrier, or
equivalent, in lieu of 10 mil plastic sheeting. The Stego Wrap should be installed according to the manufacturer's
recommendations.
Concrete is a rigid, brittle material that can withstand very little strain before cracking. Concrete, particularly
exterior hardscape is subject to dimensional changes due to variations in moisture of the concrete, variations in
temperature and applied loads. It is not possible to eliminate the potential for cracking in concrete; however,
cracking can be controlled by use of joints and reinforcing. Joints provide a pre-selected location for concrete to
crack along and release strain and reinforcement provides for closely spaced numerous cracks in lieu Of few larger
visible cracks. Crack control joints should have a maximum spacing of 5 feet for sidewalks and 10 feet each way
for slabs. Differential movement between buildings and exterior slabs, or between sidewalks and curbs may be
decreased by doweling the slab into the foundation or curb.
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Exterior slabs should be at least 4 inches thick and should be reinforced with at least 6x6, W2.9/W2.9 welded wire
fabric o No. 3 bars spaced at 18 inches on center, each way, supported firmly at mid-height of the slab.
4.10 Corrosivity
Corrosion series tests consisting of pH, soluble sulfates, soluble chlorides, and minimum resistivity were performed
on selected samples of the on-site soils. Soluble sulfate levels for the on-site fill soils indicate a negligible sulfate
exposure for concrete in contact with site soils. Accordingly, no special considerations are required for concrete
placed in contact with the on-site soils. However, it is recommended that Type II cement to be used for all concrete.
Based on the soluble chloride levels the on-site soils have a degree of corrosivity to concrete and metals that is
negligible. Based on the resistivity, the on-site soils have a degree of corrosivity to ferrous metals that is severely
corrosive. The actual corrosive potential is determined by many factors in addition to those presented herein.
MTGL, Inc. does not practice corrosion engineering. Underground metal conduits in contact with the soil need to
be protected. We recommend that a corrosion engineer be consulted.
4.11 Retaining Walls
Embedded structural walls should be designed for lateral earth pressures exerted on the walls. The magnitude of
these earth pressures will depend on the amount of deformation that the wall can yield under the load. If the wall
can yield sufficiently to mobilize the full shear strength of the soils, it may be designed for the active condition. If
the wall cannot yield under the applied load, then the shear strength of the soil cannot be mobilized and the earth
pressures will be higher. These walls such as basement walls should be designed for the at rest condition. If a
structure moves towards the retained soils, the resulting resistance developed by the soil will be the passive
resistance.
For design purposes, the recommended equivalent fluid pressure for each case for walls constructed above the
static groundwater table, backfilled with low expansive soils, and where remedial grading has been performed is
provided below. Retaining wall backfill should be compacted to at least 9096 relative compaction based on the
maximum density defined by ASTM D1557. Retaining structures may be designed to resist the following lateral
earth pressures.
Allowable Bearing Pressure —3,000 psf
Coefficient of Friction (Soil to Footing) —0.35
Passive Earth Pressure - equivalent fluid weight of 350 pd
(Maximum of 2,000 pcf)
At rest lateral earth pressure -60 pd
Active Earth Pressures - equivalent fluid weights:
!eLofkReta1nediMateriaI1
Level
1I!Iid1WII1IW(J
40
2:1(H:V) 55
We recommend that all retaining wall footings be embedded at least 24 inches below the lowest adjacent finish
grade. In addition, the wall footings should be designed and reinforced as required for structural considerations.
Page 10 of 14
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Carlsbad, California MTGL Lon No. 19-2317
Lateral resistance parameters provided above are ultimate values. Therefore, a suitable factor of safety should be
applied to these values for design purposes. The appropriate factor of safety will depend on the design condition
and should be determined by the project Structural Engineer. If any super-imposed loads are anticipated, this
office should be notified so that appropriate recommendations for earth pressures may be provided.
Retaining structures should be drained to prevent the accumulation of subsurface water behind the walls. Back
drains should be installed behind all retaining walls exceeding 3.0 feet in height. A typical detail for retaining wall
back drains is presented as Figure 3. All back drains should be outlet to suitable drainage devices. Walls and
portions thereof that retain soil and enclose interior spaces and floors below grade should be waterproofed and
damp-proofed in accordance with the 2019 CBC. We expect that retaining walls, if constructed, will not exceed
three feet in height.
For retaining walls exceeding six (6) feet in height, we recommend that a seismic retaining wall design be
performed by the project structural engineer. For seismic design we used a peak acceleration of 0.42g calculated
from the modified seismic design parameters (Ss/2.5). For a restrained wall condition, such as basement walls,
we recommend a seismic load of 18H be used for design. The seismic load is dependent on the retained wall
height, where H is the height of the wall, in feet, and the calculated triangular loads result in pounds per square
foot exerted on the base of the wall and zero at the top of the wall.
4.12 Foundation Setbacks
Utility trenches, swimming pools, and biorentention basins that are adjacent to foundations should not extend
into the footing influence zone defined as the area within a line projected at a 1:1 (horizontal to vertical) drawn
from the bottom edge of the footing.
4.13 Bio Retention Basin
Any bio retention basin proposed for the site should be designed by the project civil engineer using the information
presented in this report. We recommend that the bio retention basin be lined with an impermeable barrier on
the sides and bottom to prevent any water from migrating laterally into the foundations of the existing structures
or behind the existing retaining walls supporting the building pad area. A subdrain should be provided beneath
the basin. Prior to discharge into the storm drain pipe, a seepage cutoff wall should be constructed at the interface
between the subdrain and storm drain pipe. The concrete cutoff wall should extend a minimum of 6 inches beyond
the perimeter of the gravel packed subdrain system.
4.14 Construction Considerations
4.14.1 Moisture Sensitive Soils/Weather Related Concerns
The upper soils encountered at this site may be sensitive to disturbances caused by construction traffic and to
changes in moisture content. During wet weather periods, increases in the moisture content of the soil can cause
significant reduction in the soil strength and its support capabilities. In addition, soils that become excessively wet
may be slow to dry and thus significantly delay the progress of the grading operations. Therefore, it will be
advantageous to perform earthwork and foundation construction activities during the dry season. Much of the
on-site soils may be susceptible to erosion during periods of Inclement weather. As a result, the project Civil
Engineer/Architect and Grading Contractor should take appropriate precautions to reduce the potential for
erosion during and after construction.
4.14.2 Drainage and Groundwater Considerations
Groundwater was not encountered in the borings drilled for this investigation. However, variations in the ground
water table may result from fluctuation in the ground surface topography, subsurface stratification, precipitation,
irrigation, and other factors that may not have been evident at the time of our exploration. Seepage sometimes
occurs where relatively impermeable and/or cemented formational materials are overlain by fill soils. We should
be consulted to evaluate areas of seepage during construction.
Page 11 of 14
I—
P$OHsit 72 axe
P. Total 72 psi• 30 H
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Carlsbad, California MTGL Log No. 19-2317
Water should not be allowed to collect in the foundation excavation, on floor slab areas, or on prepared subgrades
of the construction area either during or after construction. Undercut or excavated areas should be sloped to
facilitate removal of any collected rainwater, groundwater, or surface runoff. Positive site drainage should be
provided to reduce infiltration of surface water around the perimeter of the building and beneath the floor slabs.
The grades should be sloped away from the building and surface drainage should be collected and discharged such
that water is not permitted to infiltrate the backfill and floor slab areas of the building.
4.14.3 Temporary Excavations and Shoring
Short term temporary excavations in existing soils may be safely made at an inclination of 1:1 (horizontal to
vertical) or flatter. If vertical sidewalls are required in excavations greater than 3 feet in depth, the use of
cantilevered or braced shoring is recommended. Excavations less than 3 feet in depth may be constructed with
vertical sidewalls without shoring or shielding. Our recommendations for lateral earth pressures to be used in the
design of cantilevered and/or braced shoring are presented below. These values incorporate a uniform lateral
pressure of 72 psf to provide for the normal construction loads imposed by vehicles, equipment, materials, and
workmen on the surface adjacent to the trench excavation. However, if vehicles, equipment, materials, etc. are
kept a minimum distance equal to the height of the excavation away from the edge of the excavation, this
surcharge load need not be applied.
SHORING DESIGN: LATERAL SHORING PRESSURES
Design of the shield struts should be based on a value of 0.65 times the indicated pressure, Pa, for the approximate
trench depth. The wales and sheeting can be designed for a value of 2/3 the design strut value.
Page 12 of 14
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Càrlsbád, California MTGL Log No. 19-2317
41nI
H
STRUT
th
I
UNDISTURBED
SOIL-
BEDDING Pa =30 Hsh psf
HEIGHT OF SHIELD, HSh =DEPTH OF TRENCH, D,, MINUS DEPTH OF SLOPE, H1
TYPICAL SHORING
DETAIL
Placement of the shield may be made after the excavation is completed or driven down as the material is
excavated from inside of the shield. If placed after the excavation, some over-excavation may be required to allow
for the shield width and advancement of the shield. The shield may be placed at either the top or the bottom of
the pipe zone. Due to the anticipated thinness of the shield walls, removal of the shield after construction should
have negligible effects on the load factor of pipes. Shields may be successively placed with conventional trenching
equipment.
Vehicles, equipment, materials, etc. should be set back away from the edge of temporary excavations a minimum
distance of 15 feet from the top edge of the excavation. Surface waters should be diverted away from temporary
excavations and prevented from draining over the top of the excavation and down the slope face. During periods
of heavy rain, the slope face should be protected with sandbags to prevent drainage over the edge of the slope,
and a visqueen liner placed on the slope face to prevent erosion of the slope face.
Periodic observations of the excavations should be made by the geotechnical consultant to verify that the soil
conditions have not varied from those anticipated and to monitor the overall condition of the temporary
excavations over time. If at any time during construction conditions are encountered which differ from those
anticipated, the geotechnical consultant should be contacted and allowed to analyze the field conditions prior to
commencing work within the excavation. All Cal/OSHA construction safety orders should be observed during all
underground work.
4.14.4 Utility Trenches
All Cal/OSHA construction safety orders should be observed during all underground work. All utility trench backfill
within street right of way, utility easements, under or adjacent to sidewalks, driveways, or building pads should
be observed and tested by the geotechnical consultant to verify proper compaction. Trenches excavated adjacent
to foundations should not extend within the footing influence zone defined as the area within a line projected at
a 1:1 (horizontal to vertical) drawn from the bottom edge of the footing. Trenches crossing perpendicular to
foundations should be excavated and backfilled prior to the construction of the foundations. The excavations
should be backfilled in the presence of the geotechnical engineer and tested to verify adequate compaction
beneath the proposed footing.
Utilities should be bedded and backfilled with clean sand or approved granular soil to a depth of at least 1-foot
over the pipe. The bedding materials shall consist of sand, gravel, crushed aggregate, or native, free draining soils
with a sand equivalence of not less than 30. The bedding should be uniformly watered and compacted to a firm
condition for pipe support.
Page 13 of 14
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Carlsbad, California MTGL bR No. 19-2317
The remainder of the backfill shall be typical on-site soil or imported soil which should be placed in lifts not
exceeding 8 inches in thickness, watered or aerated to near optimum moisture content, and mechanically
compacted to at least 90% of maximum dry density (ASTM D1557).
4.14.5 Site Drainage
The site should be drained to provide for positive drainage away from structures in accordance with the building
code and applicable local requirements. Unpaved areas should slope no less than 2% away from structure. Paved
areas should slope no less than 1% away from structures. Concentrated roof and surface drainage from the site
should be collected in engineered, non-erosive drainage devices and conducted to a safe point of discharge. The
site drainage should be designed by a civil engineer.
The recommendations provided in this report are based on preliminary design information and subsurface
conditions as interpreted from the investigation. Our preliminary conclusion and recommendations should be
reviewed and verified during site grading and revised accordingly if exposed Geotechnical conditions vary from
our preliminary findings and interpretations. The Geotechnical consultant should perform Geotechnical
observation and testing during the following phases of grading and construction:
During site grading and over-excavation.
During foundation excavations and placement.
During placement of retaining wall backdrains and backfill.
During excavation and backfilling of all utility trenches
When any unusual or unexpected Geotechnical conditions are encountered during any phase of
construction.
5.00 LIMITATIONS
The findings, conclusions, and recommendations contained in this report are based on the site conditions as they
existed at the time of our investigation, and further assume that the subsurface conditions encountered during
our Investigation are representative of conditions throughout the site. Should subsurface conditions be
encountered during construction that are different from those described in this report, this office should be
notified immediately so that our recommendations may be re-evaluated.
This report was prepared for the exclusive use and benefit of the owner, architect, and engineer for evaluating the
design of the project as it relates to geotechnical aspects. It should be made available to prospective contractors
for information on factual data only, and not as a warranty of subsurface conditions included in this report.
Our investigation was performed using the standard of care and level of skill ordinarily exercised under similar
circumstances by reputable soil engineers and geologists currently practicing in this or similar localities. No
warranty, express or implied, is made as to the conclusions and professional advice included in this report.
This firm does not practice or consult in the field of safety engineering. We do not direct the Contractor's
operations, and we are not responsible for their actions. The contractor will be solely and completely responsible
for working conditions on the job site, including the safety of all persons and property during performance of the
work. This responsibility will apply continuously and will not be limited to our normal hours of operation.
The findings of this report are considered valid as of the present date. However, changes in the conditions of a
site can occur with the passage of time, whether they are due to natural events or to human activities on this or
adjacent sites. In addition, changes in applicable or appropriate codes and standards may occur, whether they
result from legislation or the broadening of knowledge.
Accordingly, this report may become invalidated wholly or partially by changes outside our control. Therefore, this
report is subject to review and revision as changed conditions are identified.
Page 14 of 14
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Carlsbad, California MTGL Log No. 19-2317
FIGURES
— — — — — — — — — — — — — — — — — — —
Go gle Maps Carlsbad
Sheraton Hotel 6
7
Go gle
Map data 02020 Google 100 ft'
VICINITY MAP
PROJECT NO. 1916A16
LOG NO. 19-2317
FIGURE
-I- - - - - - - — - - - - -
__,•
-
—
. -.•. •-
\;__. -..
-- _(;j.•.
4.. . rsç.a,a2..rrS . •e "
"5" .. . -•.. .
-. • •.
/
- ---•••-.•.--. .-. •
IN
- •:- . - .. .•• • —-',I
- - •. . • ... -- '.- . .•------ r.. .3 S 'WING POOL . - y. • .. .. . -
:P!r-? ' • . .. - - - :.
- -
-
;p-
____________________
(77 / ALV
N
LEGEND
B1
BORING LOCATION
A A
SUBSURFACE PHOHLE
LX1STIG -Cl[I
-OUTBUILDING
EST1M
BASE MAP: GRADI NG PLAN 5V EXCE ENG NEERNG DATED 422:20
A A'
B-2 B-3 I
PROJECTED 10' NE
PROJECTED 25 NE
225 _.- PROPOSED PAD EL. 223.55' 225
--
-_._. APPROX. EXISTING SURFACE
215 FILL 215
Lu
_____ ______ ____ _____ _____ -,
LL
z Q 205
J 205 0 Qop OLD PARALIC DEPOSITS
ui
Lu
195
- 195 SCALE: 1'= 10
SUBSURFACE PROFILE
Project No. 1916A16
MTGL1I Inc.Log No. 19-2317
FIGURE 3
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Cãdsbad. California MTGL Log No. 19-2317
Soil backfill, compacted to
Retaining wall 90% relative compaction"
4
4
Wall waterproofing
per architects
specifications
Filter fabric envelope
(Mirafi 140N or approved
equivalent) **
Provide open cell head
joints or outlet drain at
50 feet on center to a
suitable drainage device
44 00 .4
0.0
10 °['3' 0•• 0 mm.
Minimum of 1 cubic foot
per linear foot of 3/4'
crushed rock
-- 3' diameter perforated
PVC pipe (schedule 40 or
equivalent) with perforations
oriented down as depicted
minimum 1% gradient to
suitable outlet.
Compacted fill .4..
Wall footing
SPECIFICATIONS FOR CLASS 2
PERMEABLE MATERIAL
(CAL TRANS SPECIFICATIONS)
Sieve Size %Passing
1" 100
314" 90-100
3/8" 40-100
No.4 25-40
No.8 18-33
No.30 5-15
No.50 0-7
No.200 0-3
Based on ASTM D1557
** If class 2 permeable material (See
gradation to left) is used in place of
3/4° - 1 1/2" gravel. Filter fabric may
be deleted. Class 2 permeable material
compacted to 90% relative compaction"
RETAINING WALL DRAINAGE DETAIL
FIGURE 4
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Carlsbad, California MTGL Loa No. 19-2317
APPENDIX A
REFERENCES
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Carlsbad, California MTGL Log No. 19-2317
American Society of Civil Engineers, ASCE/SEl Standard 7-16, Minimum Design Loads and Associated Criteria for
Buildings and Other Structures.
Anderson, J.G., Rockwell, T.K., Agnew, D.0 (1989). Past and Possible Future Earthquakes of Significance to the San
Diego Region, Earthquake Spectra, Vol. 4, No. 2, pp 299-335.
California Building Standards Commission (2019). 2019 California Building Code, July 2019.
California Division of Mines and Geology, 1997, Fault-Rupture Hazard Zones in California, Special Publication 42.
California Emergency Management Agency (2009). Tsunami Inundation Map For Emergency Planning, Encinitas
Quadrangle, June 1.
California Geological Survey, 2008, Guidelines for Evaluating and Mitigating Seismic Hazards in California, Special
Publication 117.
Excel Engineering (2020). Grading Plans For Carlsbad Ranch PA No. 5, dated April 22.
Kennedy, Michael P. and Siang Tan (2005). Geologic Map of the Oceanside 30' x 60' Quadrangle, California, USGS
Digitally Prepared.
MTGL, Inc. (2015). Geotechnical Investigation, Marbrisa Resorts - Phase Ill, Grand Pacific Resorts, Carlsbad,
California, dated April 24.
U.S. Geologic Survey (2017). Design Maps Summary Report, httD://geóhazards.usgs.gov/
U.S. Geologic Survey (2008). 2008 National Seismic Hazard Maps - Source Parameters.
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Carlsbad. California - MTGL Log No. 19-2317
1!J
PROGRAM
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Carlsbad. California - MTGL Log No. 19-2317
APPENDIX B
FIELD EXPLORATION PROGRAM
The subsurface conditions for this Geotechnical Investigation were explored by excavating four exploratory
borings. The exploratory borings were excavated using a 6-inch diameter hollow-stem-auger to a maximum depth
of 41.5 feet below existing grade. The approximate locations of the borings are shown on the Site Plan (Figure 2).
The field exploration was performed under the supervision of our engineer who maintained a log of the subsurface
soils encountered and obtained samples for laboratory testing. All drive samples were obtained by SPT or
California Tube Sampler.
Subsurface conditions are summarized on the accompanying Logs of Borings. The logs contain factual information
and interpretation of subsurface conditions between samples. The stratum indicated on these logs represents the
approximate boundary between earth units and the transition may be gradual. The logs show subsurface
conditions at the dates and locations indicated, and may not be representative of subsurface conditions at other
locations and times.
Identification of the soils encountered during the subsurface exploration was made using the field identification
procedure of the Unified Soils Classification System (ASTM D2488). A legend indicating the symbols and definitions
used in this classification system and a legend defining the terms used in describing the relative compaction,
consistency or firmness of the soil are attached in this appendix. Bag samples of the major earth units were
obtained for laboratory inspection and testing, and the in-place density of the various strata encountered in the
exploration was determined
The exploratory borings were located in the field by using cultural features depicted on a preliminary site plan
provided by the client. Each location should be considered accurate only to the scale and detail of the plan utilized.
The exploratory borings were backfilled in accordance with County of San Diego Environmental Health standards,
using bentonite chips in the upper twenty (20) feet of borings and soil cuttings below twenty feet depth.
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Carlsbad. California - MTGL Loa No. 19-2317
UNIFIED SOIL CLASSIFICATION SYSTEM
GRAVELS Clean Gravels (less Well-graded gravels, gravel-sand mixtures,
are more than half of than 5% fines) GW little or no fines
. coarse fraction larger Poorly-graded gravels, gravel-sand mixtures,
than #4 sieve
Gravels with fines GP little or no fines
bO m SANDS Clean Sands (less GM Silty Gravels, poorly-graded gravel-
I! r4- are more than half of than 5% fines) ______ sand-silt mixtures iM 3 coarse fraction larger Clayey Gravels, poorly-graded gravel-
than #4 sieve Sands with fines GC sand-clay mixtures
Well-graded sands, gravelly sands,
CL SW little or no fines 4-
II Poorly-graded sands, gravelly sands,
F sp little or no fines SILTS AND CLAYS _____
Silty Sands, poorly-graded sands- -c 4.' - Liquid Limit SM gravel-clay mixtures w w Less than 50
Clayey Sands, poorly-graded sand- --
-. SC gravel-silt mixtures
Inorganic clays of low to med plasticity,
C A ML gravelly, sandy, silty, or lean clays 1 m
4- 0 Inorganic clays of low to med plasticity, U) U-
. .
CL gravelly, sandy, silty, or lean clays
Organic silts and clays 8 .S E (1 . 01 of low plasticity Z w c SILTS AND CLAYS Inorganic silts, micaceous or diatomaceous U. Liquid Limit MH fine sands or silts Greater than 50
Inorganic clays of high plasticity, CH fat clays
Organic silts and clays of medium OH to high plasticity
Highly Organic Soils PT Peat, humus swamp soils with
_____________________________________________________ high organic content
GRAIN SIZE SIZE PROPORTION
Description Sieve Size Gath%ie AprximatêSie - Trace - Less than 5%
Boulders >12" >12" Larger than basketball-sized Few - 5% to 10%
Cobbles 3"- 12" 3"- 12" Fist-sized to basketball-sized Little — 15% to 20% I Coarse %"- 3" %"- 3" - Thumb-sized Some — 30% to 45% Gravel Fine #4 - W 0.19" —0.75" Peat-sized to thumb-sized Mostly - 50% to 100%
Coarse #10 - #4 0.079"-0.19" Rock salt-sized to pea-sized MOISTURE CONTENT
Sand Medium #40 - #10 0.017" - 0.079" Sugar-sized to rock salt-sized Dry —Absence of moisture
Fine #200 - #40 0.0029" — 0.017" Flour-sized to sugar-sized I Moist - Damp but not visible
I.Fines Passing#200 <0.0029" Flour-sized or smaller I Wet — Visible free water
CONSISTENCY FINE GRAINED SOILS RELATIVE DENSITY COARSE GRAINED SOILS
Apparent
DensIty
SPT
(Blows/Foot)
Mod CA Sampler
(Blows/Foot)
Apparint
Density
SPT
(Blows/Foot).
Wwbkisimpler
(Blows/Foot)
Very Soft <2 <3 Very Loose <4 <5
Soft 2-4 3-6 Loose 4-10 5-12
Firm 5-8 7-12 Medium Dense 11-30 13-35 Stiff 9-15 13-25
- Dense 31-50 36-60
Very Stiff 16-30 26-50 Very Dense <50 <60
Hard >30 >50
BORING NO. B-I
Logged by: SJC
Method of Drilling: 6-inch diameter hollow-stem auger
I
I wIwI
iII
I I
xl <ll Q:. I UJ il DESCRIPTION a.
I Jwii lII a5 I I o
I
I m lalmi a I S i
Date Drilled: 1111412019
Elevation:
COMMENTS
ogre an sunae -
I Reddish brown, medium dense, moist, fine to medium silty sand (SM) (Fill)
119.3 11.2 Grades to fine to medium clayey sand (SC) 30
10 9.0 Grades to medium brown, medium dense, moist, fine to medium silty sand 22 SPY
11 (SM) (Fill)
12
13
14
15 50/6 - -10.3 Reddish brown, very dense, most, fine-to medium grained silty sandstone, I
16 (SM) (Old Paralic Deposits)
17
18
19
20 114.5 7.9 Becomes light brown sand with silt sandstone, friable (SP-SM) 4450/1
21
22
23
24
25
26
10.7 Grades to yellowish brown, dense, moist, fine silty sandstone friable (SM)
(Old Paralic Deposits)
49 P
27
28
29
30
Sample disturbed
BORING NO. B-I
Logged by: SJC Date Drilled: 1111412019
Method of Drilling: 6-inch diameter hollow-stem auger Elevation:
I.- Ui w - - -J i Q. a.
IL
'
DESCRIPTION COMMENTS a. Ui e
9 0 C
30 51 7.3 Becomes dense to very dense, grades to sand with silt sandstone, friable (SP-SM)
31
32
33.
34
35 47 7.1
36
37
38
39
40 6.0
41
42 - - Boring terminated at 41.5 feet. No ground w8ter encountered.
Boring backfilled with bentonite chips in upper 20 feet.
BORING NO. B-2
Logged by: SJC
Method of Drilling: 6-Inch diameter hollow-stem auger
, I t IL lII U. I I
, I III , I I x I I- I ( I iUIi 43I I < I DESCRIPTION ° I I IwIl III th I I
I m iolrel o I i
Date Drilled: 1111412019
Elevation:
COMMENTS
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
irt surface -
Reddish brown, medium dense, moist, fine to medium silty sand (SM) (Fill)
119.71 9.4
129.1 1 9.8 Grades to reddish brown to dark gray, dense, moist, fine to medium silty sand with
chunks of silty fat clay (SM/SC) (Fill)
127.91 10.9 IGrades to medium brown, dense, moist, fine to medium silty sand (SM)
34 *t. 109.2 12.0 Reddish brown, medium dense, moist, fine to medium grained silty
I sandstone, friable (SM) (Old Paralic Deposits)
L 8omg terminated at 16.5 feet No ground water encountered I Boring backfilled with bentonite chips.
BORING NO. B-3
sic
ruling: 6-inch diameter hollow-stem auger
I -1 I IQ I w I I
- I I DESCRIPTION II- I ! I 0
I
I I oll 0 I I
Logged by:
Method of C
I a.
U)
w
0 m
Date Drilled: 11/1412019
Elevation:
COMMENTS
I
2
3
4
5
6
7
8
9
10
II
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
ium brown, medium dense, moist, fine to medium silty sand (SM) with chunks
dark gray, silty fat clay (SM/SC) (Fill)
No recovery, rock in
sampler shoe.
123.1 110.8
124.61 11,1 IBecomes dense
very aense, tine
Paralic Deposits)
112.31 9.2
backfilled with bentonite chips.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
40
BORING NO. B-4
Logged by: SJC Date Drilled: 1111412019
Method of Drilling: 6-inch diameter hollow-stem auger Elevation:
E a. a. UI a- ( U) <
I- DESCRIPTION COMMENTS W > 2 -I Z 'ii
U)
0 M 0 m o
dium brown, medium dense, moist, fine to medium silly sand (SM) with chunks
dark gray, silty fat clay (SM/SC) (Fill)
125.91 8.1
92.0 1 30.9 Olive gray, stiff, moist, silty fat clay (CH) Sample of clay chunks
Grades to medium brown, medium dense, moist, fine to medium silty sand
with silty fat clay chunks (SM/SC) (Fill)
105.91 17.6
15fl Drown, cense to very dense, moist, fine to medium grained silty sandstone,
s (SM) (Old Paralic Deposits)
Cobble in sampler
shoe; no recovery
gray, medium dense, moist, fine to medium sand, trace silt (SP)
5.9
water
backfilled with bentonite chips.
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Carlsbad, California MTGL Log No. 19-2317
I
APPENDIX C
LABORATORY TEST PROCEDURES
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Carlsbad, California MTGL Loa No. 19-2317
APPENDIX C
LABORATORY TESTING PROCEDURES
Classification
Soils were classified visually, generally according to the Unified Soil Classification System. Classification tests
were also completed on representative samples in accordance with ASTM D422 for Grain Size. The test
resultant soil classifications are shown on the Boring Logs in Appendix B.
In-Situ Moisture/Density
The in-place moisture content and dry unit weight of selected soil samples were determined using relatively
undisturbed samples from the Cal Tube Sampler. The dry unit weights and moisture contents are shown on
the Boring Logs in Appendix B.
Direct Shear
Direct Shear Tests were performed on in-place samples of site soils in accordance with ASTM D3080. The
test results are presented in Figures C-i and C-2.
Expansion lndè*
Expansion Index testing was completed in accordance with the standard test method ASTM D4829. Test
results are presented below.
Location $Øfl pslnd4 *pansIon
Index
B-2 at to Silty sand with fat clay chunks
(SM/SC) - Brown 17 Very Low
B-4 at 5' to Silty sand with fat clay chunks
(SM/SC) - Brown 16 Very Low
S. Corrosion
Chemical testing was performed on a representative sample to determine the corrosion potential of the
onsite soils. Testing consisted of Ph, chlorides (CTM 422), soluble sulfates (CTM 417), and resistivity (CTM
643). Test results are as follows:
I 5 leI ty
(hrniII =100 on
_
B-4 at 5' to 10' 7.6 197 275 f 600
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Carlsbad, California MTGL Log No. 19-2317
APPENDIX D
SEISMICITY
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Carlsbad., California MTGL Log No. 19-2317
APPENDIX D
SEISMICIIY
Seismicity analysis was conducted for the subject site in order to develop parameters for structural design. The
specifics of the seismicity analysis are presented below.
USGS FAULT SOURCE PARAMETERS: The USGS website was used to identify the source parameters of known
active faults near the site. The information is generated from inputting the coordinates of the site. The results
are presented herein. The printout includes the name of the fault, distance from the site, and other fault
parameters.
CBC SEISMIC DESIGN PARAMETERS: The USGS website was used to calculate the 2019 California Building Code
site specific design parameters based on ASCE 7-16 and a Soil Site Class C. The results are presented herein.
U.S. Geological Survey - Earthquake Hazards Program
Unified Hazard Tool
Please do not use this tool to obtain ground motion parameter values for the design code reference
documents covered by the U.S. Seismic Design Maps web tools (e.g., the International Building Code
and the ASCE 7 or 41 Standard). The values returned by the two applications are not identical.
A Input
Edition Spectral Period
Dynamic: Conterminous U.S. 2014 (update Peak Ground Acceleration
Latitude Time Horizon
Decimal degrees Return period in years
33.1330154 2475
Longitude
Decimal degrees, negative values for western longitudes
I -117.31070378
Site Class
537 m/s (Site class C)
... ?''
t:1C)
A Deaggregation
Component
Total
Mode (largest m-r bin)
m: 6.9
r: 9.05 km
Lo: 0.84o
Contribution: 17.14%
m: 6.9
r: 8.67 km
.: 0.82 a
Contribution: 15.27%
Mode (largest m- r- bin)
Summary statistics for, Deaggregation: Total
Deaggregation targets Recovered targets
Return period: 2475 yrs Return period: 2676.4925 yrs
Exceedance rate: 0.0004040404 yr' Exceedance rate: 0.00037362332 yr'
PGA ground motion: 0.5087914g
Totals Mean (over all sources)
Binned: 100% m: 6.73
Residual: 0% r: 12.19 km
Trace: 0.11 % a: 1.090
Discretization
r: min=0.0, max= 1000.0, A=20.0 km
m: min = 4.4, max = 9.4, A = 0.2
a: min = -3.0, max = 3.0, a = 0.5 a
Epsilon keys
£0: 1--..-2.5)
£1: [-2.5..-2.0)
e2: [-2.0..-1.5)
all: [-1.5..-1.0)
14: [-1.0..-0.5)
5: [-0.5..0.0)
a6: [0.0..0.5)
£7: [0.5..1.0)
all: [1.0.. 1.5)
0: [1.5.. 2.0)
110: [2.0 .. 2.5)
all: [2.5..+-]
Deaggregation Contributors
Source Set I. Source Type r In ao Ion let az %
UC33brAvg_FM31 System 39.62
Rose Canyon [18] 8.53 6.95 0.77 117.386GW 33.089VN 235.23 24.03
Oceanside atti [0] 14.97 7.06 1.04 117.596°W 33.057°N 252.48 4.18
Carlsbad [5] 13.63 7.19 0.92 117.463'W 33.036°N 232.87 2.28
Rose Canyon [16] 9.27 6.61 1.00 117.3620W 33.062°N 211.22 1.95
Elsinore (Temecula) rev [5] 36.44 7.63 2.01 117.00&W 33.341°N 50.51 1.43
Rose Canyon [17] 8.53 6.55 1.01 117.386'W 33.089°N 235.23 1.09
Rose Canyon [15] 11.28 6.39 1.46 117.3399W 33.035VN 193.33 1.04
UC33brAvg_FM32 System 34.79
Rose Canyon [18] 853 6.98 0.77 117,386°W 33.089VN 235.23 22.84
Oceanside a1t2 [6] 15.04 7.65 0.70 117.598°W 33.061°N 253.33 1.94
Rose Canyon [16] 9.27 6.49 1.11 117.3620W 33.062°N 211.22 1.57
Elsinore (Temecula) rev [5] 36.44 7.66 1.99 117.0080W 33.341'N 50.51 1.54
Carlsbad (5] 13.63 6.68 1.28 117.463'W 33.036'N 232.87 1.39
Rose Canyon [171 8.53 6.59 0.99 117.386'W 33.089°N 235.23 1.06
UC33brAvg_FM31 (opt) Grid 12.92
PointSourceFinite: -117.311,33.164 6.28 5.48 1.07 117.311°W 33.164VN 0.00 1.52
PointSourceFinite: -117.311,33.164 6.28 5.48 1.07 117.311°W 33.164°N 0.00 1.52
PointSourceFinite: -117.311,33.200 8.27 5.93 1.14 117.311°W 33.200°N 0.00 1.45
PointSourceFinite: -117,311,33.200 8.27 5.93 1.14 117.3I1VW 33.200'N 0.00 1.45
UC33brAvg_FM32 (opt) Grid 12.68
PointSource Finite: -117.311,33.164 6.28 5.48 1.07 117.311°W 33.164°N 0.00 1.50
PointSourceFinite: -117.311,33.164 6.28 5.48 1.01 117.311GW 33.164N 0.00 1.50
PointSource Finite: -117.311, 33.200 8.27 5.93 1.14 117.311'W 33.200°N 0.00 1.45
PointSourceFjnjte: -117.311,33.200 8.27 5.93 1.14 117.311°W 33.200'N 0.00 1.45
5111/2020 2008 National Seismic Hazard Maps - Source Parameters
U.S. Geological Survey - Earthquake Hazards Program
2008 National Seismic Hazard Maps - Source Parameters
New Search
Pref
fli,I nce
Name Slip Dip Dip Slip Rupture Rupture
Length
n Mifrs " tt
Rate (degrees) Dir Sense
Top Bottom
(km)
(mmjyr) (km) (km)
5.06 Rose Canyon CA I 1.5 90 V strike0
8 70 slip
5.06 .NpQjjlllglewood Connected alt 1 CA 1.3 89 strike 0 11 208 slip
5.06 tglgpor1.1flglewond Connected alt CA 1.3 90 V strike
0 11 208 slip
7.09 g)pot31flglewood (Offshore) CA 1.5 90 V strike
0 10 66 slip
20.97 Coronado Rank CA 3 90 V
strike 0 9 186 slip
20.97 Palos Verdes Connected CA 3 90 V strike 0 10 285 slip
2260 Eiclnoie;T+J+CM CA n/a 85 NE strike
0 16 169 slip
22.60 !lsinore; M CA 3 84 NE s trike 0 17 118 slip
22.60 ElsinoreW CA strike+Gii'T+J n/a 84 NE 0 16 199 slip
22.60 Elsinore;W'Gl+T CA n/a 84 NE stilke 0 14 124 slip
22.60 EIsinoiP;Gi'T4JsCM CA n /a 86 NE strike 0 16 195 slip
22,60 sInoie;QJ] CA 5 90 V s trike
0 14 78 slip
22.60 EisInore;I± CA n/a 86 NE
strike
0 17 127 slip
22.60 flsluore:W+Gl+T+J+CM CA n /a , 84 NE strike
0 16 241 slip
22.60 ElslnoreJ CA 3 84 NE strike0
19 75 slip
22.60 Eisinpre:I CA 5 90 V :tip 0 14 52 slip
22.60 Elsinoto;jj CA n/a 86 N1
s trike
0 17 153 slip
1/6
5/11/2020 2008 National Seismic Hazard Maps-Source Parameters
34.09 Eisinore;Qi CA 5 90 V strike 0 13 37
slip
34.09 Elsinore;&±1 CA n/a 81 NE strike
14 83 slip
36.61 Palos Verdes CA 3 90 vstrike
14 99 SLIP
38.31 San Joaguin Hills CA 0.5 23 SW thrust 2 13 27
42.10 £tth.ivakeVaUey. CA 2 90 v stdke 0 19 20 i slip
47.23 San Jaclnto;SBV+SJV+A+CC+B CA n/a 90 v strike 0.1 15 215 SLIP
47.23 SalLlad strikento;SBV+SJV+A+C CA n/a 90 V • 0 17 181 slip
47.23 San ialnt9;SBVSJVA CA n/a 90 V strike0
16 134 slip
47.23 San Jacinto;A+CC*8+SM CA n/a 90 v strike 15 178 slip
47.23 San Jacinto;A4Cc+B CA n/a 90 V strike
0.1 15 152 SLIP
trike 47.23 San Jacinto; CA n/a 90 v 0 16 118
47.23 San Jacinto;8± CA n/a 90 v strike
slip 17 118
47.23 San JacInto;SJVAiCCfB+SN CA n/a 90 V strike 0.1 15 196 slip
I strike 47.23 San iacinLo:SJV+ACC+B CA n/a 90 V 0.1 15 170 . slip
s trike 47.23 San Jadnto:SJV+A4CC CA n/a 90 V . 0 16 136 slip
strike 47.23 San Jncinto;sJVi.A+C CA n /a 90 V 0 17 136 slip
47.23 San Jncin1og CA n/a 90 v
strike
0 17
89 slip
47.23 San Jacinto:A CA 9 90 V
strike
0 iT 71 slip
47.23 Sail Jacin1ôSBV+SJVA+CC*8SM CA n/a 90 V strike 0.1 15 241 slip
47.23 SauJacinLo;Sl1V*SJVAsCC CA n/a 90 V strike 0 16 181 slip
48.94 San iarinto;SBV+SJV CA n/a 90 V strike
16 88 slip
48.94 Sall Jaciiito; CA 18 90 V strike 0 16 43
slip
https://earthquake.usgs.gov/cfusion/hazfaults_2oo8_seaJquery_rsults.cfm 2/6
511112020 2008 National Seismic Hazard Maps - Source Parameters
48.95 IR2Lk!rjgtewd,.aLLL CA 1 89 strike 0 IS 65 slip
49.89 £hflQ CA 1 65 Sw strike 0 ii 29 slip
50.06 Sail iadifloC CA 4 90 V strike 0 18 43 SUP
50.06 San Jacinto;c± CA n/a 90 V strike
isLip 0.2 14 77
strike 50.06 San Jaciiitq;CC+B+SM CA n/a 90 V 0.2 14 103 SUP
50.63 Elsinore; CA 2.5 75 NE :ke 0 14 46 lip
52.24 San Jac;nto CA 14 90 V strike 0 .17 47 sLip
52.26 £.aa.J. CA 1 50 Sw strike 0 9 24 lip
57.52 Elshiora;çj CA 3 82 NE strike 0 13 39 slip
61.09 San Jacinto CA 6 90 v strike 0 1.6 45 SUP
61,76 Puente Hills CA 0.7 26 N thrust 2.8 15 17
63.37 S. Son Andreas;NM+SM4NSB+SSB+BG.CO CA n/a 84 strike 0.1 U 340 slip
63.37 S. Son AndrPas;NM+SM4NSBiSSB.BG CA n/a 83 strike 0 14 271 slip
63,37 S. San Aridreas;SS8+I3G+CG CA n/a 77 strike 0.2 12 170 slip
63.37 S. SanAndrac;SMi'NSBiSSB.flG+CO CA n/a83 strike 0.1 13 303 slip
63.37 S. SanAnd,eas;SM+NSB+SSB+8G CA n/a 81 strike 13 234 slip
strike 63.37 Andreas;PK+CH+CC+BB.NMPSM+NSB+SSI3IBG+Cp CA n/a 86 slip 0.1 13 548
63.37 L.U11 CA n/a 86 strike 0.1 13 479 Andreac:PK+CH+Cc+BD+NM+SM+NSB+SS8+BG slip
63.37 S. San Andras;NS84'SSB+8G CA n/a 75 strike 0 14 136 SUP
63.37 S. San Andreas;k CA n/a 58 strike
13 56 slip
63.37 1.5m
Andrea s;CH'•CCRB#NM 'SM4NSB+SSB+BG+CO CA n/a 86 strike
slip 0.1 13 512
63.37 S. San Andreas;l3liiNM.SM+NSB+SSB+l3(1c0 CA n/a 85 stiike 0.1 13 390
https:llearthquake.usgs.govIcrusionIhazfaults_2oo5_searchlqu,y_resuus.cfm 316
5/112020 2008 National Seismic Hazard Maps - Source Parameters
slip
63.37 S San AndreasSSR+RG CA I n/a s ii e 13 101 slip
63.37 . S.SanAndrpasNSS+SSB+BG+CO CA n/a 79 strike 0.2 12
206 slip
63.37 S.SanAndreas:CHICC+BB+NM+SM.NSB#SSfl4BG CA n/a 86 strike 0 14 442 slip
63.37 S.SanAndraas;DQ± CA n/a 72 :;ke 0.3 12 125 li
53.37 SSanAndreas;BR+NM+SM+NSRsSSB+RG CA n/a 84 strike 0 14 321 slip
63.37 S.sanAndrcas;CCiflB+NM+SM4NSB+sSB+BG CA n/a 95 strike 14 380 slip
63.37 S. San Anci,eas:CC±BB+NM+SM+NSB.SSB+BG+Cp CA n/a 86 strike 0.1 13 449 slip
63.59 S.SanAndreas; CA 16 90 V strike
0 13 43 slip
63.59 S. San Andreas;NSB#SSB CA n/a 90 v strike 0 13 79 slip
63,59 S.SanAi1dreasPK+CH+CC+RA4NMI.SM.NsB.sSp CA n/a 90 V strike 0.1 13 421 shp
63.59 S. San AllclreaS:CC458+NM+SM+NSB+SSB CA n/a 90 V strike 0 14 322 slip
63.59 S.SflAIIdrS;C14+CC.eas,NM4SM+NSS+SSB CA n/a ' 90 I V strike 0 14 384 slip
63.59 S. San Andreas:SMINSBs CA n/a strikeSSB 90 V . 0 13 176 slip
63.59 S. San Andrea s;BB+NM+SM+NSB.ssa CA n/a 90 V strike 0 14 263 slip
63.59 SSpnAndre.1%:NMISM4NSfl+SSB CA n/a 90 V strike 0 13 213 slip
64.24 Sail Jacinto ; CA 4 90 V strike
0.7 13 34 lip
64.24 San Jacinto;I±M CA n/a 90 V strike
0.4 12 61 slip
68.53 CA 0.7 29 N thrust 2.8 15 11
69.95 San Jose CA 0.5 74 NW strike
15 20 slip
70.29 S. San MuIteasJil CA 22 90 v strike 0 13 35 slip
70.29 &SanAlIdIea;l'K+CII4.CCIpBsNM+sMiNsB CA n/a 90 v strike 0.1 13 377 slip
4/6
5111/2020 2008 National Seismic Hazard Maps - Source Parameters
70.29 S.SanAndreas;NM.SM+Nss CA n/a 90 V strike 0 13 170
slip
70.29 S. San Andreas:cCsBB+NM+SM+NSB CA n/a 90 V strike 0 14 279 slip
70.29 S. San A,idieas:BS+NM+SM*NSB CA n/a 90 V strike 0 14 220
.slip
70,29 SSanAndrsasCH4CC4BBNM+SM+NSB CA n/a 90 V strike 0 14 341 • slip
• r
70.29 S. San Andreas;SM+NSB CA Na 90 V strike0
13 133 slip
71.93 Cucamonga CA 5 45 N thrust 0 8 28
72.07 Pinto Mtn CA • 25 90 V strike 0 16 74 slip
72.62 Sierra Madre CA 2 53 N reverse 0 14 57
72.62 Sierra Madre Connected CA 2 51 reverse 0 14 76
74.42 PuenteHllls (u). CA 0.7 27 N thrust 2.1 15 22
16.26 &S CA strikeanAndreas;çQ 20 90 V 0.6 11 69 Slip
76.62 Burnt Mtn CA 0.6 67 W strike0
16 21 slip
78.74 Qi1Qia CA 3 90 V Strike 16 25 slip
78.96 ysiaiiParklUpt, CA 1.3 50 NE reverse 3 15 20
79.83 San Jachito;M CA n/a 90 V strike
slip 0 12 26
79.85 Eureka Peak CA 0.6 90 V strike 0 15 19 slip
81.11 BaYAWAd CA 1.5 79 N
strike
0 16 22 slip
81.65 North Frontal (1&5I1 CA 1 49 S reverse 0 16 50
82.04 Clanishcll.Sawpjj CA 0.5 50 NW reverse 0 14 16
82.36 $jp6tilition hills CA 4 90 v Strike
0,6 12 36 slip
82.72 S.SanAtulreas;BB+NM+SM CA n/a 90 V strike 0 14 184 slip
82.72 &SanAndreas;CH+CC+BB+NM+SM CA n/a 90 V
strike
0 14 306 slip
82.12 S. San Andrea ;SR CA 29 90 V strike
0 13 98 slip
82.72 S. San Antlieas;CC+RB+NM'Su CA n/a so V strike 0 14 243 slip
https:IIeahquake.usgs.goV/cfushazfaufts_2oo8seah/queryresul.cfm 54
5/11/2020 2008 National Seismic Hazard Maps - Source Parameters
82.77 S. San Andreas;NM+SM CA n/a 90 V strike 0 14 134
slip I
8277 S. San Andteps;PIcCH+CC+flB41M+SM CA n/a 90 tj strike
0.1 13 342 slip
84.27 ludup CA 0.5 55 NE reveise 0 15 29
84.74 Elmore Ranch CA 1 90 V strike 0 ii 29 sl.p
86.24 1iuy.11 CA 1 70 N strike
0 17 17 slip
86,96 Helendale.Sptockhart CA 0.6 90 v strike 0 13
114 sLip
87.51 gunaSalada CA 3.5 90 v strike 0 33 99 slip
87.66 Santa Monica Connected alt 2 CA 2.4 44 strike 0.8 13 93
I slip
87.85 Landers CA 0.6 90 v strike 0 15 95 slip
88.03 North Frontal () CA 0.5 41 $ thrust 0 16 27
90.56 Santa Monica .j CA 1 75 N strike 0 18 14 slip
90.56 Santa Monica Connected all 1 CA 2.6 51 strike
16 79 slip
92.25 Lenwood-ckharOld Woman Sorjg CA 0.9 90 V strike
0 13 145 slip
93.41 Malibu Coast, CA 0.3 strikeI2 74 N 0 16 38 slip
93.41 MalIbu Coac,9jJ, CA 0.3 75 N strike 0 8 38 slip
9421 pa.flunIe,.ft..a CA 3 41 N thiust 1.2 12 65
95.00 Johnson Valley_(fQ) CA 0.6 90 v strike 0 16 35 slip
95.82 SoEmerson-ConperMt,, CA 0.6 90 V strike 0 14 54 sdp
97.23 SierraMridre (SanFei nandoI CA 2 45 N thrust ( 13 18
97.89 Calico.HidalgQ CA 1.8 90 V strike
14 117 slip
98.98 Sari Gabriel CA 1 61 N strike
15 It Slip
99.11 jpa.DLnne1jjj CA 3 45 N thrust 0 16 51
6/6
5/11/2020 2008 National Seismic Hazard Maps - Source Parameters
U.S. Geological Survey - Earthquake Hazards Program
2008 National Seismic Hazard Maps - Source
Parameters
New Search
Fault Name State
Rose Canyon I California
GEOMETRY
Dip (degrees) 90
Dip direction V
Sense of slip strike slip
Rupture top (km) 0
Rupture bottom (km) - 8
Rake (degrees) 180
Length (km) 70
MODEL VALUES
Slip Rate is.
Probability of activity
-
' 1
ELLS WORTH HANKS
Minimum magnitude 6.5 6.5
Maximum magnitude 6.90 6.70
b-value I 0.8 0.8
Fault Model Deformation CharRatet GR-a-va1ue1 Weight
https:llearthquake.usgs.gov/cfuslon/hazfaults_2008_search/vlew_fault.cfm?cfault_id=127def 1/2
5/11/2020 2008 National Seismic Hazard Maps - Source Parameters
Model
-
UnStitched 2.1 8.68e-04/1.73e-03 1.989/2.366 0.50
UnStitched 2.4 8.68e-04/1.73e-03 1.989/2.366 0.50
- --
1 1st Value is based on Ellsworth relation and 2nd value is based on Hanks and Bakun
relation
Comments
Mininum slip rate reported by LindvaLL and Rockwell (1995). 2002 Fault length
extended to the south to include the Silver Strand fault.
212
5/11/2020 2008 National Seismic Hazard Maps - Source Parameters
U.S. Geological Survey- Earthquake Hazards Program
2008 National Seismic Hazard Maps - Source
Parameters
New Search
Fault Name State
Newport Inglewood Connected alt 1 California
GEOMETRY
Dip (degrees) I 89
Dip direction
I Sense ofslip strikeslip
i
Ru ptu re top (k m) o
Rupture bottom (km) 11
Rake (degrees) r 180
Length (km) 208
MODEL VALUES
Slip Rate 1.3
Probability of activity 1
-
ELLSI HANKS
-
Minimum magnitude 6.5 6.5
Maximum magnitude 7.50 7.50
b-value 0.8 0.8
Fault Model Deformation Char Rate 1 GR-a.-value1 Weight
https:lleadhquake.usgs.gov/cfusion/hazlaults_2008_search/view_fault.ctm?cfault_id=127_altl 1/2
511112020 2008 National Seismic Hazard Maps - Source Parameters
Model
f I
Stitched 2.1, j 3.79e-04j3.79e-04 L884/1.884 L0.50
1 1st Value is based on Ellsworth relation and 2nd vaLue is based on Hanks and Bakun
relation
Comments
I Rose Canyon; Newport-Inglewood (Offshore); Newport-Inglewood, alt 1
Selected References
I Working Group on California Earthquake Probabilities, 1995, Seismic hazards in
southern California—ProbabLe earthquakes, 1994 to 2024: Bulletin of the
Seismological Society of America, v.85, no. 2, p. 379-439.
212
OSHPD
Sheraton Hotel 6
Latitude, Longitude: 33.13330154, -117.31070378
Sheraton Carlsbad
Resort & Spa
c 'S S
S
S - •. S 5,.
Map data 02020 Google Google
M7 7 Mile Kitchen
Takeout
Date 511312020, 10:11:55 AM
Design Code Reference Document ASCE7-18
Risk Category Ill
Sit. Clue
-
C - Very Dense Soil and Soft Rock
Type Value Description
SS 1.04 MCER ground motion. (for 0.2 second period)
81 0.377 MCER ground motion. (fOr 1.09 period)
Sms 1.248 Site-modified spectral acceleration value
SMI 0.586 Site-modIfied spectral acceleration value
Ss 0.832 Numeric seismic design value at 0.2 second SA
SDI 0.377 Numeric seismic design value at 1.0 second SA
Typo Value Description
SDC 0 Seismic design category
Fe 1.2 Site amplification factor at 0.2 second
F,, 1.5 Site amplification factor at 1.0 second
PGA 0.457 MCE0 peak ground acceleration
FpGA 1.2 Site amplification factor at PGA
PGAr,j 0.549 Site modified peak ground acceleration
TL 8 Long-period transition period In seconds
SeRT 1.04 Probabilistic risk-targeted ground motion. (0.2 second)
SsUH 1.163 Factored uniform-hazard (2% probability of exceedanca In 50 years) spectral acceleration
SaD 1.5 Factored deterministic acceleration value. (02 second)
SIRT 0.377 Probabilistic rIsk-targeted ground motion. (1.0 second)
SILIH 0.416 Factored uniform-hazard (2% probability of exceedanco in 50 years) spectral acceleration.
SID 0.6 Factored deterministic acceleration value. (1.0 second)
PGAd 0.524 Factored deterministic acceleration value. (Peak Ground Acceleration)
CRS 0.894 Mapped value of the risk coefficient at short periods
CR1 0.906 Mapped value of the risk coefficient at a period of 19
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
carlsbadCalifornia. MTGL Lon No. 19-2317.
APPENDIX E
STANDARD GRADING, SPECIFICATIONS.
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
I Carlsbad. California MTGL Loa No. 19-2317
APPENDIX E
GENERAL EARTH WORK AND GRADING SPECIFICATIONS
GENERAL
These specifications present general procedures and requirements for grading and earthwork as shown on the
approved grading plans, including preparation of areas to be filled, placement of fill, installation of subdrains, and
excavations. The recommendations contained in the attached geotechnical report are a part of the earthwork and
grading specifications and shall supersede the provisions contained herein in the case of conflict. Evaluations
performed by the Consultant during the course of grading may result in new recommendations, which could
supersede these specifications, or the recommendations of the geotechnical report.
EARTHWORK OBSERVATION AND TESTING
Prior to the start of grading, a qualified Gèotechnical Consultant (Geotechnical Engineer) shall be employed for
the purpose of observing earthwork procedures and testing the fills for conformance with the recommendations
of the geotechnical report and these specifications. It will be necessary that the Consultant provide adequate
testing and observation so that he may determine that the work was accomplished as specified. It shall be the
responsibility of the Contractor to assist the Consultant and keep them apprised of work schedules and changes
so that he may schedule his personnel accordingly.
It shall be the sole responsibility of the Contractor to provide adequate equipment and methods to accomplish
the work in accordance with applicable grading codes or agency ordinances, these specifications and the approved
grading plans.
Maximum dry density tests used to determine the degree of compaction will be performed in accordance with the
American Society for Testing and Materials Test Method (ASTM) D1557.
PREPARATION OF AREAS TO BE FILLED
Clearing and Grubbing: All brush, vegetation and debris shall be removed or piled and otherwise disposed of
Processing: The existing ground which is determined to be satisfactory for support of fill shall be scarified to a
minimum depth of 12 inches. Existing ground, which is not satisfactory, shall be over-excavated as specified in the
following section and in the text of this report.
Overexcavation: Soft, dry, spongy, highly fractured or otherwise unsuitable ground, extending to such a depth
that surface processing cannot adequately improve the condition, shall be over-excavated down to firm ground,
approved by the Consultant.
Moisture conditioning: Over-excavated and processed soils shall be watered, dried-back, blended, and mixed as
required to have a relatively uniform moisture content near the optimum moisture content as determined by
ASTM D1557.
Re-compaction: Over-excavated and processed soils, which have been mixed, and moisture conditioned uniformly
shall be recompacted to a minimum relative compaction of 90 percent of ASTM D1557
Benching: Where soils are placed on ground with slopes steeper than 5:1 (horizontal to vertical), the ground shall be
stepped or benched. Benches shall be excavated in firm material for a minimum width of 4 feet.
Sheraton Hotel 6— Geotechnical Investigation MTGL Project No. 1916A16
Carlsbad, California -- MTGL Loa No. 19-2317
FILL MATERIAL
General: Material to be placed as fill shall be free of organic matter and other deleterious substances and shall be
approved by the Consultant.
Oversize: Oversized material defined as rock, or other irreducible material with a maximum dimension greater
than 12 inches, shall not be buried or placed in fill, unless the location, material, and disposal methods are
specifically approved by the Consultant. Oversize disposal operations shall be such that nesting of oversized
material does not occur, and such that the oversize material is completely surrounded by compacted or densified
fill. Oversize material shall not be placed within 10 feet vertically of finish grade or within the range of future
utilities or underground construction, unless specifically approved by the Consultant.
Import: If importing of fill material is required for grading, the import material shall meet the general
requirements.
FILL PLACEMENT AND COMPACTION
Fill Lifts: Approved fill material shall be placed in areas prepared to receive fill in near-horizontal layers not
exceeding 6 inches in compacted thickness. The Consultant may approve thicker lifts if testing indicates the
grading procedures are such that adequate compaction is being achieved with lifts of greater thickness. Each layer
shall be spread evenly and shall be thoroughly mixed during spreading to attain uniformity of material and
moisture in each layer.
Fill Moisture: Fill layers at a moisture content less than optimum shall be watered and mixed, and wet fill layers
shall be aerated by scarification or shall be blended with drier material. Moisture conditioning and mixing of fill
layers shall continue until the fill material is at uniform moisture content at or near optimum.
Compaction of Fill: After each layer has been evenly spread, moisture conditioned, and mixed, it shall be uniformly
compacted to not less that 90 percent of maximum dry density in accordance with ASTM D1557. Compaction
equipment shall be adequately sized and shall be either specifically designed for soil compaction or of proven
reliability, to efficiently achieve the specified degree of compaction.
Fill Slopes: Compacting on slopes shall be accomplished, in addition to normal compacting procedures, by
backrolling of slopes with sheepsfoot rollers at frequent increments of 2 to 3 feet as the fill is placed, or by other
methods producing satisfactory results. At the completion of grading, the relative compaction of the slope out to
the slope face shall be at least 90 percent in accordance with ASTM D1557.
Compaction Testing: Field tests to check the fill moisture and degree of compaction will be performed by the
consultant. The location and frequency of tests shall be at the consultant's discretion. In general, these tests will
be taking at an interval not exceeding 2 feet in vertical rise, and/or 1,000 cubic yards of fill placed. In addition, on
slope faces, at least one test shall be taken for each 5,000 square feet of slope face and/or each 10 feet of vertical
height of slope.
SUBDRAIN INSTALLATION
Subdrain systems, if required, shall be installed in approved ground to conform to the approximate alignment and
details shown on the plans or herein. The subdrain location or materials shall not be changed or modified without
the approval of the Consultant. The Consultant, however, may recommend and, upon approval, direct changes in
subdrain line, grade or materials. All subdrains should be surveyed for line and grade after installation and
sufficient time shall be allowed for the surveys, prior to commencement of fill over the subdrain.
EXCAVATION
Excavations and cut slopes will be examined during grading. If directed by the Consultant, further excavation or
overexcavation and refilling of cut areas, and/or remedial grading of cut slopes shall be performed. Where fill over
cut slopes are to be graded, unless otherwise approved, the cut portion of the slope shall be made and approved
by the Consultant prior to placement of materials for construction of the fill portion of the slope.