HomeMy WebLinkAboutPA2021-308_20211222_Soils Report_8-17-21August 17, 2021
Mr. Jack Langson Project No: 72572-00
c/o PMR Construction, Inc. Report No: 21-8975
2061 Fairweather Road
Santa Ana, California 92705
Attention: Mr. Chris Miller
Subject: Preliminary Geotechnical Investigation
Proposed New Single-Family Residence
2676 Bayshore Drive
Newport Beach, California
INTRODUCTION
This report presents findings and conclusions of a preliminary geotechnical investigation
undertaken to relate onsite and certain regional geotechnical conditions to the construction of a
new single-family residence on the subject property. Analyses for this investigation are based
upon the conceptual architectural plans for the property prepared by Skurman Architects.
The conclusions and recommendations of this report are considered preliminary as they precede
the development of finalized structural plans, the formulation of which are partially dependent
upon the recommendations presented herein.
Scope of Investigation
The investigation included the following:
1.Analysis of pertinent reports, maps, aerial photographs, and published literature
pertaining to the site and nearby areas, as well as project plans, in order to relate
geotechnical conditions to proposed construction.
2.Field reconnaissance and logging of three limited-access cone penetration tests to
evaluate the character and geometrical distribution of soil materials within the proposed
construction area.
3.Laboratory testing was performed on this and adjacent sites to evaluate maximum
density/optimum moisture content, grain size, direct shear strength, soluble sulfate and
corrosivity.
4.Analyses of data and the preparation of this geotechnical report presenting conclusions
and recommendations for site development in accordance with the 2019 California
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Building Code and the City of Newport Beach Building Code Policy CBC 1803.5.11-12.
This report is suitable for use by your design professionals, contractors, and submittal to
the City of Newport Beach.
Accompanying Illustrations and Appendices
Figure 1 - USGS Geologic Location Map
Figure 2 - CDMG Geologic Hazards Location Map
Figure 3 - Typical Retaining Wall Subdrain Detail
Figure 4 - Geotechnical Plot Plan
Appendix A - References
Appendix B - CPT and Boring Logs
Appendix C - Current and Previous Field Exploration and Laboratory Test Results
Appendix D - Liquefaction Analysis
Appendix E - Standard Grading Specifications
Appendix F - Utility Trench Backfill Guidelines
Site Description
The roughly trapezoidal-shaped property fronts approximately 80± feet along Bayshore Drive
and extends southwesterly up to 245± feet, which is 45± feet beyond the rear bulkhead. A
topographic survey provided by Civilscapes Engineering, indicates the relatively flat building
pad is at an average elevation of 13± feet (NAVD 88). The site is currently developed with a
circa-1985 wood-frame, two-story single-family residence. The adjacent properties to the east
and west are developed with similar single-family homes.
Proposed Development
Based on a review of conceptual plans prepared by Skurman Architects, proposed site
improvements generally include the demolition and removal of the existing development to
allow the construction of a new two-story single-family residence at or near existing site grades.
Proposed exterior improvements include the construction of a new landscaping and hardscaping
and replacement of portions of the existing bulkhead. The new residence is anticipated to be
supported on a shallow stiffened foundation system designed in accordance with the Newport
Beach Building Code Policy CBC 1803.5.11-12. Exterior elements are anticipated to be
supported on conventional foundations and slabs on grade constructed in new engineered fill.
GEOTECHNICAL CONDITIONS
Geologic Setting
The property is located on Harbor Island adjacent to Newport Bay as depicted on the USGS
Geologic Index Map, Figure 1. It is located 0.60± miles northerly of the Pacific shoreline,
approximately 1.9± miles easterly of the Newport pier and is 0.41± miles southwesterly of a
former sea bluff on the inland side of Bayside Drive. Review of old topographic maps indicates
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that prior to dredging of Newport Bay, the site location was a low lying, likely intertidal area
adjacent to a shallow channel of the natural bay. The site is underlain at a depth in excess of 50
feet by an accumulation of bay and beach deposits and subsequent dredge fill placed during land
reclamation. A younger generation of fill from construction of the existing roads and residence
may underlie the property at the surface.
Earth Materials
Based on the results of our CPT study, Dredge Fill underlies the site at the surface to an
interpreted depth of 8± feet and generally consist of sand and silty sand. Up to 3± feet of silty
and clayey fill soils were encountered in the rear yard and may have been locally placed to
elevate the pad during original grading. Bay deposits underlie the dredge fill and is capped with
a 1± foot thick layer of bay mud at an elevation roughly equivalent to mean sea level. Below
this depth, silty sand and sand were encountered to a maximum explored depth of 46± feet.
Cone penetrometer test data reveal that the earth materials underlying the site are variably dense
within the upper 24± feet, becoming very dense below. Recompacted dredge fill is considered
suitable for the support of new foundations.
With the exception of the locally placed fine-grained fill in the rear yard, onsite materials are
generally non-expansive on the basis of visual classification; laboratory testing of the similar
soils on nearby sites indicates negligible soluble sulfate concentrations.
Groundwater
Groundwater was inferred at a depth of 5± feet below grade during our field exploration.
Groundwater depth should be expected to fluctuate in response to tidal shifts. Groundwater is
not considered to be a geotechnical constraint affecting the design and construction of proposed
at-grade improvements.
Street Flooding and Surface Drainage
Localized street flooding associated with heavy rains and high tides has been a recurrent
phenomenon in some low-lying areas of Newport Beach. The potential for flooding affecting
proposed development should be evaluated by the project civil engineer. The proposed
development may modify surface drainage, which should be evaluated and improved as
necessary by the architect or civil engineer.
Seismic Considerations
Published Studies
One of the principals of seismic analyses and prediction is the premise that earthquakes are more
likely to occur on geologically younger faults, and less likely to occur on older faults. For many
years studies have described faults with Holocene movement (within the last 11,000 years) as
“Active”, and faults with documented Pleistocene movement (within the last 1.6 million years)
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and with undetermined Holocene movement as “Potentially Active”. Informally, many studies
have described faults documented to have no Holocene movement as “Inactive”. Recent
geologic and seismic publications are attempting to clarify the nomenclature describing faults to
more accurately represent the potential affects from earthquakes.
Reports by the California Division of Mines and Geology indicate faults with documented
Holocene or Historic (within the last 200 years) movement should be considered Active.
However, Potentially Active faults are more appropriately characterized in terms of the last
period of documented movement. The Fault Activity Map of California (Jennings, C.W.; 2010)
defines four categories for onshore Potentially Active faults. The categories are associated with
the time of the last displacement evidenced on a given fault and are summarized in Table 1.
Table 1, Definitions of Fault Activity in California
It is important to note these categories embrace all Pre-Holocene faults as Potentially Active, and
provide no methodology to designate a given fault as “Inactive”. Although the likelihood of an
earthquake or movement to occur on a given fault significantly decreases with inactivity over
geologic time, the potential for such events to occur on any fault cannot be eliminated within the
current level of understanding.
Local and Regional Faults
The closest published active fault to the site is the offshore extension of the Newport-Inglewood
Fault Zone, approximately 1.2 miles southwest, (Blake, T.F., 2000, CGS/2004). Other active
faults in the vicinity of the site include the San Joaquin Hills, approximately 7.5 miles away, the
Palos Verdes Fault, approximately 14.2 miles to the west; the Coronado Bank Fault,
approximately 46.0 miles southwest; the Elsinore Fault, approximately 26.3 miles to the east,
and the San Andreas Fault, approximately 62.0 miles to the northeast.
The California Geological Survey updated the Fault Parameters and Earthquake Catalog for the
probabilistic Seismic Hazards Maps in 2002. This update included the addition of the San
Joaquin Hills blind thrust fault indicated above, theorized to exist from Newport Beach to Dana
Point, and ramping up inland to the Irvine area, and essentially underlying the site. Earthquakes
of Magnitude 6.6 are presently postulated for this structure. With the fault’s location at
approximately 7.5 miles distant, it is calculated as the most significant seismic source to affect
the site.
Activity Category Recency of Movement
Active Historic Within the last 200 years
Holocene Within the last 11,000 years
Potentially Active
Late Quaternary Within the last 700,000 years
Quaternary Within the last 1.6 million years
Pre-Quaternary Before the last 1.6 million years
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Historic Ground Motion Analyses
Utilizing attenuation relationships (Bozorgnia, et al.; 1999, unconstrained/Holocene sediments),
one can estimate the ground motion history of the site. The study indicates the maximum site
acceleration from 1800 to 2004 was approximately 0.5g and occurred during the magnitude 6.3
Long Beach Earthquake 2.8 miles from the site on March 11, 1933.
It is noted that the estimation of historic peak ground acceleration presented above is provided
for the interest of the client and is required by local (City or County) review agencies. The value
derived is not directly utilized in structural design of residential structures. Seismic parameters
for use by the structural engineer in accordance with 2019 California Building Code in design of
the proposed structure(s) are presented in the recommendations portion of this report.
Site Classification for Seismic Design
Review of the Seismic Hazards Zones Map (California Division of Mines and Geology, 1998)
for the Newport Beach Quadrangle, Figure 2, indicates this lot is not located within a “zone of
required investigation” for earthquake induced landslides, but is located in a liquefaction hazard
zone. Please refer to the Appraisal of Liquefaction Potential above for more information.
For the purposes of determining seismic design parameters provided in the Recommendations
portion of this report pertaining to the new structures, the upper one hundred feet of soil
underlying the subject site has been classified in accordance with Section 1613.2.2 of the 2019
CBC and Section 20.1 of ASCE 7-16. Although the soils underlying the site are liquefiable and
classify as F per the 2019 CBC, requiring a site-response analysis, proposed new structures are
anticipated to have fundamental periods of vibration less than 0.5 seconds (to be verified by the
structural engineer). As such, Section 20.3.1 in ASCE 7-16 provides an exception that indicates
such liquefiable sites may be classified in accordance with Table 20.3-1 without performing an
evaluation.
Given the exception and the results of our onsite and nearby field investigations, which indicate
the site is predominantly underlain by earth materials with average interpreted N-values between
15 and 50, seismic design criteria may be calculated using a site classification of D. However,
the Site Class remains F.
Appraisal of Liquefaction Potential
Review of the Seismic Hazard Zones Map for the Newport Beach Quadrangle (California
Division of Mines & Geology, 1998) identifies the site and all of the Newport/Balboa peninsula
and harbor within a zone of required investigation for liquefaction. In accordance with City of
Newport Beach Building Code Policies CBC-1803.5 and 1803.5.11-12 and the California
Geological Survey SP117A (2008), our office has performed an analysis for liquefaction
potential based on the CPT data collected during our onsite investigation.
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Based on the results of our analysis presented in Appendix D, which indicates liquefaction
settlement within the upper 50 feet is less than inches, a stiffened foundation system or mat
slab designed in accordance with the City’s “Shallow Mitigation Methods” may be utilized as
recommended herein.
Please note that an evaluation of lateral spreading, which is typically integral to liquefaction
analyses, is not considered necessary based on our review of the proposed bulkhead replacement
plan prepared by PMA Consulting, Inc. Lateral spreading is not considered a geotechnical
design constraint following construction of the new bulkhead.
Secondary Seismic Hazards
Other secondary seismic hazards can include deep rupture, shallow ground cracking, and tsunami
inundation. With the absence of active faulting onsite, the potential for deep fault rupture is not
present. The potential for shallow ground cracking to occur during an earthquake is a possibility
at any site, but does not pose a significant hazard to site development. Regarding tsunami
inundation, please refer to the appropriate section above for more information.
CONCLUSIONS
1. The proposed development at the subject site is considered geotechnically feasible
provided the recommendations herein are integrated into design, construction, and long-
term maintenance of the property. Proposed construction should not affect or be affected
by adjacent properties provided appropriate construction methods and care are
implemented.
2. The property is underlain at a depth greater than 46± feet by bedrock strata of Monterey
Formation, which are successively overlain by sandy bay deposits and 8± feet of dredge
fill.
3. The removal and re-compaction of the upper 3± feet of existing soil for the entire site is
recommended prior to construction of new foundations.
4. Granular onsite soils are non-expansive, are expected to have a negligible soil soluble
sulfate level, and a very low potential for corrosion of buried metal based on prior
adjacent laboratory testing. However, as placed concrete is in a marine environment, a
moderate sulfate exposure may be used for design purposes. The concrete mix should be
designed by a concrete expert in consideration of structural requirements. The appropriate
exposure should be evaluated by the architect and/or structural engineer.
5. No active faults are known to transect the site and therefore the site is not expected to be
adversely affected by surface rupturing. It will, however, be affected by ground motions
from earthquakes during the design life of the residence.
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Liquefaction analysis performed in accordance with City Building Code Policies
CBC-1803.5 and 1803.5.11-12 and SP117A (CGS, 2008) indicates seismic settlement
withinthe upper 50 feet of subgrade soils is less the inches. Therefore, a mat slab or
stiffenedfoundation system designed in accordance with the City’s “Shallow Mitigation
Methods”may be utilized as recommended herein.
Groundwater was inferred at a depth of 5± feet below grade during our field exploration.
Groundwater depth should be expected to fluctuate in response to tidal shifts.
Groundwater is not considered to be a geotechnical constraint affecting the design and
construction of proposed at-grade improvements.
The potential of street flooding affecting the residence during its lifetime is deferred to
the project civil engineer.
Surface discharge onto or off the site should be appropriately controlled with proper
engineering design and site grading.
The proposed residence may be supported on a stiffened shallow foundation designed in
accordance with the Newport Beach Building Code Policy CBC 1803.5.11-12.
RECOMMENDATIONS
Site Preparation and Grading
1. General
Grading should be performed in accordance with the recommendations herein and the
Standard Grading Specifications in Appendix E. Grading is anticipated to consist of
remedial over-excavation and minor cut/fills to construct the proposed building pad and
foundation subgrades. Processing, over-excavation and re-compaction should be
observed, tested and approved in writing by a representative of this firm.
2. Remedial Grading
Remedial grading is recommended to include removal and re-compaction of existing
near-surface soils three feet below existing site grades. Locally deeper removals may be
required pending field review by the geologist.
Finer grained, potentially expansive soils encountered in the rear yard are recommended
to be relocated as necessary to future landscape areas pending field review by the
geologist or field technician during grading.
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3. Removal of Existing Improvements
Existing vegetation, organic materials and/or construction and demolition debris should
be removed and disposed of offsite.
4. Compaction Standard
Onsite soil materials are anticipated to be suitable for re-use as compacted fill providing
they are free of rubble and debris. Materials should be placed at 120 percent of optimum
moisture content and compacted under the observation and testing of the soil engineer to
at least 90 percent of the maximum dry density as evaluated by ASTM D 1557.
5. Temporary Construction Slopes
Although not anticipated, significant temporary slopes exceeding 3 feet should be cut in
accordance with Cal/OSHA Regulations. It is anticipated that the onsite soils may be
classified as Type C soil, and temporary cuts with a sloping ratio of 1.5:1 (horizontal:
vertical) may be appropriate; however, the material exposed in temporary excavations
should be evaluated by the contractor during construction.
The safety of temporary construction slopes is deferred to the general contractor, who
should implement the safety practices as defined in Section 1541, Subchapter 4, of
Cal/OSHA T8 Regulations (2006).
Shoring should be anticipated where space limitations preclude temporary slope layback,
in any location where onsite personnel may be in close proximity to open excavations
greater than 5 feet in total height. Shoring also should be anticipated where wet materials
are exposed.
Foundation Design Parameters
Due to the potential for liquefaction at the site, we recommend that a stiffened foundation or mat
slab be used for the proposed structure in accordance with the City of Newport Beach Building
Code Policy No. CBC-1803.5.11-12. Such a foundation system should be founded on properly
compacted fill derived from onsite materials.
1. Bearing Capacity and Settlement
The allowable bearing capacity for a stiffened foundation or mat slab placed on approved
recompacted fill with a thickness of 12 inches or more is 2,000 pounds per square foot.
Foundation settlement from structural loading is estimated to be ¾ inch total and ½ inch
differential over a distance of 30 feet. The majority of the static foundation settlement
should occur during construction. Total and differential settlements during the probable
design earthquake are estimated at ¾-inch and 1/2 inch, respectively. Total and differential
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settlements during the maximum considered earthquake are estimated at 1.5 and 1 inch,
respectively.
2. Lateral Loads
Lateral loads may be resisted by passive pressure forces and friction acting on the bottom
of foundations. Passive pressure may be computed from an equivalent fluid density of 150
pounds per cubic foot above the groundwater table, not to exceed 2,000 pounds per square
foot. A coefficient of friction of 0.25 may be used in computing the frictional resistance.
These values may be combined without reduction.
3. Reinforcement
Foundations and slabs should be reinforced in conformance with the requirements of the
structural engineer. From a geotechnical viewpoint, a minimum of two No. 5 bars should
be incorporated at the top and bottom of continuous footings in order to reduce the
potential for cracking during seismic shaking or as a result of subsurface imperfections.
Monitoring
Complete documentation of the pre- and post-construction conditions of adjacent improvements
should be undertaken. In addition, monitoring of ground movement and construction vibrations
should be made as an integral part of the construction. Such documentation should include:
1. A sufficient number of photographs to establish the existing condition of nearby
structures.
2. Establishment of a sufficient number of ground elevation control stations so that potential
subsidence or heave associated with grading and lateral movement can be detected.
Monitoring of such points should be accomplished during all grading, shoring (if any),
and excavation work.
3. Ground vibration monitoring during construction to capture peak particle velocities of
drilling, tracking, and excavation activities is recommended. Vibration monitors should
be Sigicom model C-22 tri-axial geophones or equal.
Hardscape Design and Construction
Hardscape improvements may utilize conventional foundations embedded in recompacted fill
designed in accordance with the foundation recommendations presented above. Foundations
should have a design depth of 18 inches or more.
Concrete flatwork should be divided into as nearly square panels as possible. Joints should be
provided at maximum 6 feet intervals to give articulation to the concrete panels. Landscaping
and planters adjacent to concrete flatwork should be designed in such a manner as to direct
drainage away from concrete areas to approved outlets. Planters located adjacent to principal
foundation elements should be sealed and drained.
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Flatwork elements should be a minimum 5 inches thick (actual) and reinforced with No. 4 bars
16 inches on center both ways.
Seismic Design
Based on the geotechnical data and site parameters, the following is provided by the USGS
(ASCE 7-16) to satisfy the 2019 CBC design criteria:
Table 2, Site and Seismic Design Criteria
for the 2019 CBC
Design
Parameters
Recommended
Values
Site Class
Site Longitude (degrees)
Site Latitude (degrees)
SS (g) B
S1 (g) B
SMS (g) D1
SM1 (g) D1
SDS (g) D1
SD1 (g) D1
Fa
Fv
Seismic Design Category
PGAM(g)
F
-117.9086
33.6125
1.384
0.492
1.384
0.891
0.923
0.594
1.00
1.81
D
0.666
1This evaluation assumes the fundamental period of vibration of proposed
structures does not exceed 0.5 second.
Finished Grade and Surface Drainage
Finished grades should be designed and constructed so that no water ponds in the vicinity of
footings. Drainage design in accordance with the 2019 California Building Code, Section 1804.4
is recommended. Roofs should be guttered and discharge conducted away from the house in a
non-erosive manner as specified by the project civil engineer or landscape architect. Proper
interception and disposal of all onsite surface discharge is presumed to be a matter of civil
engineering or landscape architectural design.
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Concrete
Soil soluble sulfate testing indicates negligible sulfate content. Onsite concrete may be exposed
to seawater. It is recommended that a concrete expert be retained to design an appropriate
concrete mix to address the structural and exposure requirements. In lieu of retaining a concrete
expert, it is recommended that the 2019 California Building Code, Section 1904.1 be utilized,
which refers to ACI 318, Table 4.3.1, and 4.2.1. The appropriate exposure should be evaluated
by the architect and/or structural engineer.
Utility Trench Backfill
Utility trench backfill should be placed in accordance with Appendix F, Utility Trench Backfill
Guidelines. It is the owners and contractor's responsibility to inform subcontractors of these
requirements and to notify Geofirm when backfill placement is to begin.
Foundation Plan Review
In order to help assure conformance with recommendations of this report and as a condition of
the use of this report, the undersigned should review final foundation plans and specifications
prior to submission of such to the building official for issuance of permits. Such review is to be
performed only for the limited purpose of checking for conformance with the design concept and
the information provided herein. This review shall not include review of the accuracy or
completeness of details, such as quantities, dimensions, weights or gauges, fabrication processes,
construction means or methods, coordination of the work with other trades or construction safety
precautions, all of which are the sole responsibility of the Contractor. Geofirm’s review shall be
conducted with reasonable promptness while allowing sufficient time in our judgment to permit
adequate review. Review of a specific item shall not indicate that Geofirm has reviewed the
entire system of which the item is a component. Geofirm shall not be responsible for any
deviation from the Construction Documents not brought to our attention in writing by the
Contractor. Geofirm shall not be required to review partial submissions or those for which
submissions of correlated items have not been received.
Jobsite Safety
Neither the professional activities of Geofirm, nor the presence of Geofirm’s employees and
subconsultants at a construction/project site, shall relieve the General Contractor of its
obligations, duties and responsibilities including, but not limited to, construction means,
methods, sequence, techniques or procedures necessary for performing, superintending and
coordination the work in accordance with the contract documents and any health or safety
precautions required by any regulatory agencies. Geofirm and its personnel have no authority to
exercise any control over any construction contractor or its employees in connection with their
work or any health or safety programs or procedures. The General Contractor shall be solely
responsible for jobsite safety.
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Pre-Grade Meeting
A pre-job conference should be held with representative of the owner, contractor, architect, civil
engineer, soils engineer, engineering geologist, and building official prior to commencement of
construction, to clarify any questions relating to the intent of these recommendations or
additional recommendations.
Observation and Testing
The 2019 California Building Code, Section 1705.6 requires geotechnical observation and
testing during construction to verify proper removal of unsuitable materials, that foundation
excavations are clean and founded in competent material, to test for proper moisture content and
proper degree of compaction of fill, to test and observe placement of wall and trench backfill
materials, and to confirm design assumptions. It is noted that the CBC requires continuous
verification and testing during placement of fill, pile driving, and pier/caisson drilling.
A Geofirm representative shall visit the site at intervals appropriate to the stage of construction,
as notified by the Contractor, in order to observe the progress and quality of the work completed
by the Contractor. Such visits and observation are not intended to be an exhaustive check or a
detailed inspection of the Contractor’s work but rather are to allow Geofirm, as an experienced
professional, to become generally familiar with the work in progress and to determine, in
general, if the work is proceeding in accordance with the recommendations of this report.
Geofirm shall not supervise, direct, or have control over the Contractor’s work nor have any
responsibility for the construction means, methods, techniques, sequences, or procedures selected
by the Contractor nor the Contractor’s safety precautions or programs in connection with the
work. These rights and responsibilities are solely those of the Contractor.
Geofirm shall not be responsible for any acts or omission of the Contractor, subcontractor, any
entity performing any portion of the work, or any agents or employees of any of them.
Geofirm does not guarantee the performance of the Contractor and shall not be responsible for
the Contractor’s failure to perform its work in accordance with the Contractor documents or any
applicable law, codes, rules or regulations.
These observations are beyond the scope of this investigation and budget and are conducted on a
time and material basis. The responsibility for timely notification of the start of construction and
ongoing geotechnically involved phases of construction is that of the owner and his contractor.
Typically, at least 24 hours’ notice is required.
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LIMITATIONS
This investigation has been conducted in accordance with generally accepted practice in the
engineering geologic and soils engineering field. No further warranty is offered or implied.
Conclusions and recommendations presented are based on subsurface conditions encountered
and are not meant to imply a control of nature. As site geotechnical conditions may alter with
time, the recommendations presented herein are considered valid for a time period of one year
from the report date. The recommendations are also specific to the current proposed
development. Changes in proposed land use or development may require supplemental
investigation or recommendations. Also, independent use of this report in any form cannot be
approved unless specific written verification of the applicability of the recommendations is
obtained from this firm.
Thank you for this opportunity to be of service. If you have any questions, please contact this
office.
Respectfully,
GEOFIRM
Erik R. Hilde, P.G., E.G. 2303 Russell C. Lamb, P.E. 38380, G.E. 2207
Associate Engineering Geologist Principal/ Chief Geotechnical Engineer
Date Signed: 8 /17 / 2021
ERH/RCL:hsm
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PA2021-308
JOB NO.:DATE:FIGURE:USGS Geologic Location Map, Santa Ana 30' x 60' Quadrangle72572-00August 20211SITE2676 Bayshore DriveNewport BeachPA2021-308
JOB NO.:DATE:FIGURE:CDMG Geologic Hazards Location Map, Newport Beach Quadrangle72572-00August 20212SITE2676 Bayshore DriveNewport BeachPA2021-308
JOB NO.:DATE:FIGURE:
Typical Retaining Wall Subdrain Detail
72572-00 August 2021 3
Onsite Native Soil Cap for
exterior ; (1.5'-2.0' MAX. thick)Select Noncohesive
Granular Backfill
(SE >30)
Retaining Wall Footing
Geotextile Filter Fabric
4" Perforated Plastic Collector Pipe
(Below Adjacent Finish Grade)
Single-sized 1/2"- 3/4" Drain Rock
(1 cubic foot per lineal foot)
Limit of Wall Excavation -
See Report for
Recommended Geometery
Typical
Retaining
Wall
Notes:This system consists of a geotextile fabric-wrapped gravel envelope. Collection is with a
4-inch diameter perforated plastic pipe embedded in the gravel envelope and tied to a 4-inch
diameter non-perforated plastic pipe which discharges at convenient locations. The outlet pipe
should be placed such that the flow gradient is not less than 2.0 percent. The geotextile fabric-
wrapped gravel envelope should be placed at a similar gradient
All drain pipes should be Schedule 40 PVC or ABS SDR-35. Perforations may be either bored 1/4-inch diameter holes or 3/16-inch slots placed on the bottom one-third of the pipe perimeter. If the pipe is to be bored, a minimum of 10 holes should be uniformly placed per foot of length. If slots are made, they should not exceed 2-1/2 inches in length and should not be closer than 2 inches. Total length of slots should not be less than 50 percent of the pipe length and should be uniformly spaced.
The fabric pore spaces should not exceed equivalent 30 mesh openings or be less than equivalent
100 mesh openings. The fabric should be placed such that a minimum lap of 8-inches exists at all
splices.
12"-18"
Finish Grade - Design May
Vary per Architect or Civil
Engineer
Alternative Weep Hole(s)
for Exterior Applications,
Design per Architect or
Civil Engineer
PA2021-308
GEOTECHNICAL PLOT PLAN2676 BAYSHORE DRIVENEWPORT BEACH, CALIFORNIASCALE: 1"=20'72572-00 21-8975AUGUST 20214JOB NO.:REPORT NO.:DATE:FIGURE:CPT-3QdfDREDGE FILLBAY/BEACH DEPOSITSAPPROXIMATE CONE PENETROMETERTEST LOCATIONEXPLANATIONQbQdfQbCPT-2CPT-3CPT-1PA2021-308
APPENDIX A
REFERENCES
PA2021-308
APPENDIX A
REFERENCES
1. Al Atik, Linda, M. ASCE, and Sitar, Nicholas, M.ASCE, 2010, Seismic Earth Pressures on
Cantilever Retaining Structures, ASCE Journal of Geotechnical and Geoenvironmental
Engineering, dated October.
2. Bozorgnia, Y., Campbell, K.W., and Niazi, M. M., 1999, “Vertical Ground Motion:
Characteristics, Relationship with Horizontal Component, and Building Code Implications”,
Proceedings of the SMIP99 Seminar on Utilization of Strong-Motion Data, pp. 23-49, dated
September 15.
3. California Building Code, 2019 Edition.
4. California Division of Mines & Geology, 1998, “Seismic Hazards Zones Map, Newport Beach
Quadrangle.”
5. California Geological Survey, 2008, “Guidelines for Evaluating and Mitigating Seismic Hazards
in California,” Special Publication 117A.
6. Geofirm, 2007, “Geofirm, 2006, “Geotechnical Investigation for Foundation Design, Proposed
Single Family Residence, 2741 Bayshore Drive, Newport Beach, California”; Project No: 71662-
00, Report No: 06-5867, dated August 31.
7. Geofirm, 2015, “Preliminary Geotechnical Investigation, Proposed New Single-Family
Residence, 2742 & 2752 Bayshore Drive, Lots 4 & 5, Tract 1014, Newport Beach, California,”
Project No. 72215-00, Report No. 15-7769, dated December 1.
8. Geofirm, 2020, “Preliminary Geotechnical Investigation, Proposed New Single-Family
Residence, 115 & 119 Via Mentone, Newport Beach, California”, Project No. 72488-00, Report
No. 20-8683.
9. Geofirm, 2021, “Preliminary Geotechnical Investigation, Proposed New Single-Family
Residence, 434 Via Lido Nord, Newport Beach, California,” Project No. 72550-00, Report No.
21-8848, dated January 22.
10. Grant et al, 1999, “Late Quaternary Uplift and Earthquake Potential of the San Joaquin Hills,
South Los Angeles Basin, California.”
11. Jennings, Charles W., et al, 1994, “Fault Activity Map of California and Adjacent Areas,”
California Division of Mines and Geology, Geologic Data Map No. 6.
12. Legg, Mark R., et al, 2003, “Evaluation of Tsunami Risk to Southern California Coastal Cities,”
Earthquake Engineering Research Institute. January
13. Morton, P.K., et al, 1973, “Geo-Environmental Maps of Orange County,” California Division of
Mines and Geology, Preliminary Report 15.
14. United States Geological Survey, 2002, "Preliminary Digital Geologic Map of the Santa Ana 30'
x 60' Quadrangle, southern California, Version 1.0".
PA2021-308
APPENDIX B
CPT LOGS
PA2021-308
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2
1
2
1
3
4
4
6
8
4
7
10
16
27
37
20
30
32
15
20
21
8
11
14
16
16
12
6
7
15
TOPSOIL: Sandy SILT. Black, organic rich, moist, loose.
SAND: Grey, moist, loose, fine grained.
SAND: Brown, wet, loose, fine-medium grained.
@7' Groundwater
SAND: Brown, wet, loose, fine grained.
SAND: Brown, wet, firm, fine grained.
SAND: Brown, wet, loose-firm, fine grained.
@14' No sample recovery
@16' No sample recovery
@18' No sample recovery
Total Depth 21.5'
Groundwater encountered 7'
Backfilled with cuttings
LOG OF BORING Depth (feet)Description
USCSUndisturbedSampleBlows/6"MoistureContent (%)Depth (feet)In-place DryDensity (pcf)Project No.: 72215-00
Date(s) Logged: 10/22/2015
Drilling Company: Native Drilling
Drop: 30-inch
Weight(s): 140# Standard
Logged By: TWK
Figure No.: B-1
Address:
Method of Drilling: 6-inch Hollow Stem Auger
Geofirm
2752 Bayshore Drive;Newport Beach, CA
BORING NO.: B-1 Geologic
Attitude
0
5
10
15
20
25
30
35Bulk Sample0
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
31
32
33
34
35
PA2021-308
6
5
7
5
5
4
3
7
7
16
20
23
TOPSOIL: Sandy SILT. Black, organic rich, moist, loose.
SAND: Grey brown, moist, loose, fine grained.
SAND: Black, moist, loose, fine-medium grained.
SAND: Black, wet, loose, fine grained.
SAND: Brown, wet, loose-firm, fine-medium grained.
Total Depth 9.5'
Groundwater encountered 8'
Backfilled with cuttings
LOG OF BORING Depth (feet)Description
USCSUndisturbedSampleBlows/6"MoistureContent (%)Depth (feet)In-place DryDensity (pcf)Project No.: 72215-00
Date(s) Logged: 10/22/2015
Drilling Company: Native Drilling
Drop: 30-inch
Logged By: TWK
Figure No.: B-2
Address:
Method of Drilling: Hand Auger
Geofirm
2752 Bayshore Drive;Newport Beach, CA
BORING NO.: B-2 Geologic
Attitude
0
5
10
15
20
25
30
35Bulk Sample0
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
31
32
33
34
35
PA2021-308
APPENDIX C
CURRENT AND PREVIOUS FIELD EXPLORATION AND LABORATORY TEST
RESULTS (2752 Bayshore Drive, Reference 7, Appendix A)
PA2021-308
APPENDIX C
CURRENT AND PREVIOUS FIELD EXPLORATION AND LABORATORY TEST
RESULTS (2752 Bayshore Drive, Reference 7, Appendix A)
I. Field Exploration Procedures
A. Onsite Field Exploration
Our field services consisted of three CPT sounding to a maximum depth of 46 feet.
Historic borings were made at 2752 Bayshore Drive and extended to depths of 9.5
and 21.5 feet below existing grade. Logs of our CPT and borings are included in
Appendix B.
B. Onsite Sampling
A representative, near-surface bulk sample was bagged and transported to the
laboratory for classification and physical testing.
C. Sampling (2752 Bayshore Drive)\
1. Standard Penetration Test
Samples of subsurface materials were obtained by driving a steel barrel drive
sampler with an effective weight of 140/40 pounds that is raised and permitted
to fall 30 inches. The sampler has an outside diameter of 2.0 inches and an
inside diameter of 1.375 inches.
The samples were removed from the sample barrel for visual analysis in the
field. Records of the number of blows required to effect each 6 inches of
penetration were made.
2. Disaggregated Samples
Bulk samples of typical soil types were bagged and transported to the
laboratory for classification and physical testing.
II. Laboratory Testing Procedures
Corrosion Test Results (2752 Bayhore Drive)
Sample Designation - Boring 1 @ 0-4’
pH - 6.9
Soluble Sulfate - 47 mg/kg
Minimum Resistivity - 2,960 ohm-cm
PA2021-308
C. Particle Size Analyses (2752 Bayshore Drive)
Particle size analyses were performed on samples in accordance with ASTM D422.
The results of the tests are presented graphically on Figure C-1.
D. Direct Shear Test (2752 Bayshore Drive)
A direct shear test was performed in general accordance with ASTM D 3080 on
remolded soil specimens inundated before and during testing. The direct shear
machine employed was a conventional single shear, strain-controlled device. The
shearing strength parameters were obtained by fitting a straight line through three
points of peak and ultimate shear strength versus total normal stress. The total
normal stress range used was 1000 to 4000 pounds per square foot. Results from
the test are summarized on Figure C-2.
E. Maximum Density and Optimum Moisture Determinations (onsite)
Optimum moisture and maximum density were determined in accordance with Test
Designation ASTM D 1557. These results are tabulated below:
Moisture Content Dry Density
Sample Location (%) Optimum (pcf) Maximum
TP-1 @ 0’ 14.4 113.4
PA2021-308
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PA2021-308
APPENDIX D
LIQUEFACTION ANALYSIS
PA2021-308
LIQUEFACTION ANALYSIS REPORT
Input parameters and analysis data
Analysis method:Fines correction method:
Points to test:Earthquake magnitude Mw:Peak ground acceleration:
NCEER (1998)NCEER (1998)Based on Ic value6.880.67
G.W.T. (in-situ):G.W.T. (earthq.):Average results interval:Ic cut-off value:Unit weight calculation:
Project title : Location :
GeoLogismiki
Geotechnical Engineers
Merarhias 56
http://www.geologismiki.gr
CPT file : CPT-1
5.00 ft5.00 ft12.60Based on SBT
Use fill:Fill height:
Fill weight:Trans. detect. applied:Kσ applied:
NoN/AN/AYesYes
Clay like behaviorapplied:Limit depth applied:Limit depth:MSF method:
Sands onlyYes46.47 ftMethod based
Cone resistance
qt (tsf)4002000Depth (ft)46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Cone resistance SBTn Plot
Ic (Robertson 1990)4321
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
SBTn Plot CRR plot
CRR & CSR 0.60.40.20
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
CRR plot
During earthq.
Qtn,cs 200180160140120100806040200Cyclic Stress Ratio* (CSR*)0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
Liquefaction
No Liquefact ion
Normalized friction ratio (%)0.1 1 10Normalized CPT penetration resistance1
10
100
1,000
Friction Ratio
Rf (%)1086420
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Friction Ratio
Mw=71/2, sigma'=1 atm base curve Summary of liquefaction potential
FS Plot
Factor of safety 21.510.50
46
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
FS Plot
During earthq.
Zone A1: Cyclic liquefaction likely depending on size and duration of cyclic loading
Zone A2: Cyclic liquefaction and strength loss likely depending on loading and ground
geometry
Zone B: Liquefaction and post-earthquake strength loss unlikely, check cyclic softening
Zone C: Cyclic liquefaction and strength loss possible depending on soil plasticity,
brittleness/sensitivity, strain to peak undrained strength and ground geometry
CLiq v.3.3.1.14 - CPT Liquefaction Assessment Software - Report created on: 5/3/2021, 2:36:05 PM
Project file: V:\72450-72999\72572 (Langson) 2676 Bayshore\CPT-Liquefaction\CLiq.clq
1
PA2021-308
This software is licensed to: Stoney-Miller Consultants, IncCPT name: CPT-1Cone resistanceqt (tsf)4002000Depth (ft)4644424038363432302826242220181614121086420Cone resistanceCPT basic interpretation plotsFriction RatioRf (%)1086420Depth (ft)4644424038363432302826242220181614121086420Friction RatioPore pressureu (psi)100-10Depth (ft)464442403836343230282624222018161412108642Pore pressureInsituSBT PlotIc(SBT)4321Depth (ft)464442403836343230282624222018161412108642SBT PlotSoil Behaviour TypeSBT (Robertson et al. 1986)1817161514131211109876543210Depth (ft)4644424038363432302826242220181614121086420Soil Behaviour TypeSensitive fine grainedSand & silty sandSand & silty sandSilty sand & sandy siltClay & silty claySand & silty sandSandSandSand & silty sandSandSand & silty sandSandSandSand & silty sandSandSand & silty sandSandCLiq v.3.3.1.14 - CPT Liquefaction Assessment Software - Report created on: 5/3/2021, 2:36:05 PM2Project file: V:\72450-72999\72572 (Langson) 2676 Bayshore\CPT-Liquefaction\CLiq.clqInput parameters and analysis dataAnalysis method:Fines correction method:Points to test:Earthquake magnitude Mw:Peak ground acceleration:Depth to water table (insitu):NCEER (1998)NCEER (1998)Based on Ic value6.880.675.00 ftDepth to water table (erthq.):Average results interval:Ic cut-off value:Unit weight calculation:Use fill:Fill height:5.00 ft12.60Based on SBTNoN/AFill weight:Transition detect. applied:Kσ applied:Clay like behavior applied:Limit depth applied:Limit depth:N/AYesYesSands onlyYes46.47 ftSBT legend1. Sensitive fine grained2. Organic material3. Clay to silty clay4. Clayey silt to siltyl5. Silty sand to sandy silt6. Clean sand to silty sand7. Gravely sand to sand8. Very stiff sand told9. Very stiff fine grainedPA2021-308
This software is licensed to: Stoney-Miller Consultants, IncCPT name: CPT-1Norm. cone resistanceQtn200150100500Depth (ft)4644424038363432302826242220181614121086420Norm. cone resistanceCPT basic interpretation plots (normalized)Norm. friction ratioFr (%)1086420Depth (ft)4644424038363432302826242220181614121086420Norm. friction ratioNom. pore pressure ratioBq10.80.60.40.20-0.2Depth (ft)4644424038363432302826242220181614121086420Nom. pore pressure ratioSBTn PlotIc (Robertson 1990)4321Depth (ft)4644424038363432302826242220181614121086420SBTn PlotNorm. Soil Behaviour TypeSBTn (Robertson 1990)1817161514131211109876543210Depth (ft)4644424038363432302826242220181614121086420Norm. Soil Behaviour TypeSensitive fine grainedSand & silty sandSilty sand & sandy siltClay & silty claySand & silty sandSandSand & silty sandSandSandSand & silty sandSandSand & silty sandSandSand & silty sandSandSandSandCLiq v.3.3.1.14 - CPT Liquefaction Assessment Software - Report created on: 5/3/2021, 2:36:05 PM3Project file: V:\72450-72999\72572 (Langson) 2676 Bayshore\CPT-Liquefaction\CLiq.clqSBTn legend1. Sensitive fine grained2. Organic material3. Clay to silty clay4. Clayey silt to siltyl5. Silty sand to sandy silt6. Clean sand to silty sand7. Gravely sand to sand8. Very stiff sand told9. Very stiff fine grainedInput parameters and analysis dataAnalysis method:Fines correction method:Points to test:Earthquake magnitude Mw:Peak ground acceleration:Depth to water table (insitu):NCEER (1998)NCEER (1998)Based on Ic value6.880.675.00 ftDepth to water table (erthq.):Average results interval:Ic cut-off value:Unit weight calculation:Use fill:Fill height:5.00 ft12.60Based on SBTNoN/AFill weight:Transition detect. applied:Kσ applied:Clay like behavior applied:Limit depth applied:Limit depth:N/AYesYesSands onlyYes46.47 ftPA2021-308
This software is licensed to: Stoney-Miller Consultants, IncCPT name: CPT-1Total cone resistanceqt (tsf)4003002001000Depth (ft)4644424038363432302826242220181614121086420Total cone resistanceLiquefaction analysis overall plots (intermediate results)SBTn IndexIc (Robertson 1990)4321Depth (ft)4644424038363432302826242220181614121086420SBTn IndexNorm. cone resistanceQtn200150100500Depth (ft)4644424038363432302826242220181614121086420Norm. cone resistanceGrain char. factorKc109876543210Depth (ft)4644424038363432302826242220181614121086420Grain char. factorCorrected norm. cone resistanceQtn,cs200150100500Depth (ft)4644424038363432302826242220181614121086420Corrected norm. cone resistanceCLiq v.3.3.1.14 - CPT Liquefaction Assessment Software - Report created on: 5/3/2021, 2:36:05 PM4Project file: V:\72450-72999\72572 (Langson) 2676 Bayshore\CPT-Liquefaction\CLiq.clqInput parameters and analysis dataAnalysis method:Fines correction method:Points to test:Earthquake magnitude Mw:Peak ground acceleration:Depth to water table (insitu):NCEER (1998)NCEER (1998)Based on Ic value6.880.675.00 ftDepth to water table (erthq.):Average results interval:Ic cut-off value:Unit weight calculation:Use fill:Fill height:5.00 ft12.60Based on SBTNoN/AFill weight:Transition detect. applied:Kσ applied:Clay like behavior applied:Limit depth applied:Limit depth:N/AYesYesSands onlyYes46.47 ftPA2021-308
This software is licensed to: Stoney-Miller Consultants, IncCPT name: CPT-1CRR plotCRR & CSR0.60.40.20Depth (ft)4644424038363432302826242220181614121086420CRR plotDuring earthq.Liquefaction analysis overall plotsFS PlotFactor of safety21.510.50Depth (ft)4644424038363432302826242220181614121086420FS PlotDuring earthq.Liquefaction potentialLPI20151050Depth (ft)4644424038363432302826242220181614121086420Liquefaction potentialVertical settlementsSettlement (in)10.50Depth (ft)4644424038363432302826242220181614121086420Vertical settlementsLateral displacementsDisplacement (in)2520151050Depth (ft)4644424038363432302826242220181614121086420Lateral displacementsCLiq v.3.3.1.14 - CPT Liquefaction Assessment Software - Report created on: 5/3/2021, 2:36:05 PM5Project file: V:\72450-72999\72572 (Langson) 2676 Bayshore\CPT-Liquefaction\CLiq.clqF.S. color schemeLPI color schemeInput parameters and analysis dataAnalysis method:Fines correction method:Points to test:Earthquake magnitude Mw:Peak ground acceleration:Depth to water table (insitu):NCEER (1998)NCEER (1998)Based on Ic value6.880.675.00 ftDepth to water table (erthq.):Average results interval:Ic cut-off value:Unit weight calculation:Use fill:Fill height:5.00 ft12.60Based on SBTNoN/AFill weight:Transition detect. applied:Kσ applied:Clay like behavior applied:Limit depth applied:Limit depth:N/AYesYesSands onlyYes46.47 ftAlmost certain it will liquefyVery likely to liquefyLiquefaction and no liq. are equally likelyUnlike to liquefyAlmost certain it will not liquefyVery high riskHigh riskLow riskPA2021-308
LIQUEFACTION ANALYSIS REPORT
Input parameters and analysis data
Analysis method:Fines correction method:
Points to test:Earthquake magnitude Mw:Peak ground acceleration:
NCEER (1998)NCEER (1998)Based on Ic value6.880.67
G.W.T. (in-situ):G.W.T. (earthq.):Average results interval:Ic cut-off value:Unit weight calculation:
Project title : Location :
GeoLogismiki
Geotechnical Engineers
Merarhias 56
http://www.geologismiki.gr
CPT file : CPT-2
5.00 ft5.00 ft12.60Based on SBT
Use fill:Fill height:
Fill weight:Trans. detect. applied:Kσ applied:
NoN/AN/AYesYes
Clay like behaviorapplied:Limit depth applied:Limit depth:MSF method:
Sands onlyYes45.02 ftMethod based
Cone resistance
qt (tsf)2000Depth (ft)44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
Cone resistance SBTn Plot
Ic (Robertson 1990)4321
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
SBTn Plot CRR plot
CRR & CSR 0.60.40.20
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
CRR plot
During earthq.
Qtn,cs 200180160140120100806040200Cyclic Stress Ratio* (CSR*)0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
Liquefaction
No Liquefact ion
Normalized friction ratio (%)0.1 1 10Normalized CPT penetration resistance1
10
100
1,000
Friction Ratio
Rf (%)1086420
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
Friction Ratio
Mw=71/2, sigma'=1 atm base curve Summary of liquefaction potential
FS Plot
Factor of safety 21.510.50
44
42
40
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
FS Plot
During earthq.
Zone A1: Cyclic liquefaction likely depending on size and duration of cyclic loading
Zone A2: Cyclic liquefaction and strength loss likely depending on loading and ground
geometry
Zone B: Liquefaction and post-earthquake strength loss unlikely, check cyclic softening
Zone C: Cyclic liquefaction and strength loss possible depending on soil plasticity,
brittleness/sensitivity, strain to peak undrained strength and ground geometry
CLiq v.3.3.1.14 - CPT Liquefaction Assessment Software - Report created on: 5/3/2021, 2:36:38 PM
Project file: V:\72450-72999\72572 (Langson) 2676 Bayshore\CPT-Liquefaction\CLiq.clq
1
PA2021-308
This software is licensed to: Stoney-Miller Consultants, IncCPT name: CPT-2Cone resistanceqt (tsf)3002001000Depth (ft)44424038363432302826242220181614121086420Cone resistanceCPT basic interpretation plotsFriction RatioRf (%)1086420Depth (ft)4442403836343230282624222018161412108642Friction RatioPore pressureu (psi)151050-5Depth (ft)44424038363432302826242220181614121086420Pore pressureInsituSBT PlotIc(SBT)4321Depth (ft)4442403836343230282624222018161412108642SBT PlotSoil Behaviour TypeSBT (Robertson et al. 1986)1817161514131211109876543210Depth (ft)44424038363432302826242220181614121086420Soil Behaviour TypeSensitive fine grainedClay & silty clayClay & silty clayClayClay & silty claySand & silty sandSilty sand & sandy siltSand & silty sandSandSandSand & silty sandSandSandSandCLiq v.3.3.1.14 - CPT Liquefaction Assessment Software - Report created on: 5/3/2021, 2:36:38 PM2Project file: V:\72450-72999\72572 (Langson) 2676 Bayshore\CPT-Liquefaction\CLiq.clqInput parameters and analysis dataAnalysis method:Fines correction method:Points to test:Earthquake magnitude Mw:Peak ground acceleration:Depth to water table (insitu):NCEER (1998)NCEER (1998)Based on Ic value6.880.675.00 ftDepth to water table (erthq.):Average results interval:Ic cut-off value:Unit weight calculation:Use fill:Fill height:5.00 ft12.60Based on SBTNoN/AFill weight:Transition detect. applied:Kσ applied:Clay like behavior applied:Limit depth applied:Limit depth:N/AYesYesSands onlyYes45.02 ftSBT legend1. Sensitive fine grained2. Organic material3. Clay to silty clay4. Clayey silt to siltyl5. Silty sand to sandy silt6. Clean sand to silty sand7. Gravely sand to sand8. Very stiff sand told9. Very stiff fine grainedPA2021-308
This software is licensed to: Stoney-Miller Consultants, IncCPT name: CPT-2Norm. cone resistanceQtn200150100500Depth (ft)44424038363432302826242220181614121086420Norm. cone resistanceCPT basic interpretation plots (normalized)Norm. friction ratioFr (%)1086420Depth (ft)44424038363432302826242220181614121086420Norm. friction ratioNom. pore pressure ratioBq10.80.60.40.20-0.2Depth (ft)44424038363432302826242220181614121086420Nom. pore pressure ratioSBTn PlotIc (Robertson 1990)4321Depth (ft)4442403836343230282624222018161412108642SBTn PlotNorm. Soil Behaviour TypeSBTn (Robertson 1990)1817161514131211109876543210Depth (ft)44424038363432302826242220181614121086420Norm. Soil Behaviour TypeOrganic soilClayClayClay & silty claySand & silty sandSandSand & silty sandSandSand & silty sandSand & silty sandSandSandCLiq v.3.3.1.14 - CPT Liquefaction Assessment Software - Report created on: 5/3/2021, 2:36:38 PM3Project file: V:\72450-72999\72572 (Langson) 2676 Bayshore\CPT-Liquefaction\CLiq.clqSBTn legend1. Sensitive fine grained2. Organic material3. Clay to silty clay4. Clayey silt to siltyl5. Silty sand to sandy silt6. Clean sand to silty sand7. Gravely sand to sand8. Very stiff sand told9. Very stiff fine grainedInput parameters and analysis dataAnalysis method:Fines correction method:Points to test:Earthquake magnitude Mw:Peak ground acceleration:Depth to water table (insitu):NCEER (1998)NCEER (1998)Based on Ic value6.880.675.00 ftDepth to water table (erthq.):Average results interval:Ic cut-off value:Unit weight calculation:Use fill:Fill height:5.00 ft12.60Based on SBTNoN/AFill weight:Transition detect. applied:Kσ applied:Clay like behavior applied:Limit depth applied:Limit depth:N/AYesYesSands onlyYes45.02 ftPA2021-308
This software is licensed to: Stoney-Miller Consultants, IncCPT name: CPT-2Total cone resistanceqt (tsf)3002001000Depth (ft)44424038363432302826242220181614121086420Total cone resistanceLiquefaction analysis overall plots (intermediate results)SBTn IndexIc (Robertson 1990)4321Depth (ft)4442403836343230282624222018161412108642SBTn IndexNorm. cone resistanceQtn200150100500Depth (ft)44424038363432302826242220181614121086420Norm. cone resistanceGrain char. factorKc109876543210Depth (ft)44424038363432302826242220181614121086420Grain char. factorCorrected norm. cone resistanceQtn,cs200150100500Depth (ft)44424038363432302826242220181614121086420Corrected norm. cone resistanceCLiq v.3.3.1.14 - CPT Liquefaction Assessment Software - Report created on: 5/3/2021, 2:36:38 PM4Project file: V:\72450-72999\72572 (Langson) 2676 Bayshore\CPT-Liquefaction\CLiq.clqInput parameters and analysis dataAnalysis method:Fines correction method:Points to test:Earthquake magnitude Mw:Peak ground acceleration:Depth to water table (insitu):NCEER (1998)NCEER (1998)Based on Ic value6.880.675.00 ftDepth to water table (erthq.):Average results interval:Ic cut-off value:Unit weight calculation:Use fill:Fill height:5.00 ft12.60Based on SBTNoN/AFill weight:Transition detect. applied:Kσ applied:Clay like behavior applied:Limit depth applied:Limit depth:N/AYesYesSands onlyYes45.02 ftPA2021-308
This software is licensed to: Stoney-Miller Consultants, IncCPT name: CPT-2CRR plotCRR & CSR0.60.40.20Depth (ft)44424038363432302826242220181614121086420CRR plotDuring earthq.Liquefaction analysis overall plotsFS PlotFactor of safety21.510.50Depth (ft)44424038363432302826242220181614121086420FS PlotDuring earthq.Liquefaction potentialLPI20151050Depth (ft)44424038363432302826242220181614121086420Liquefaction potentialVertical settlementsSettlement (in)1.510.50Depth (ft)44424038363432302826242220181614121086420Vertical settlementsLateral displacementsDisplacement (in)20151050Depth (ft)44424038363432302826242220181614121086420Lateral displacementsCLiq v.3.3.1.14 - CPT Liquefaction Assessment Software - Report created on: 5/3/2021, 2:36:38 PM5Project file: V:\72450-72999\72572 (Langson) 2676 Bayshore\CPT-Liquefaction\CLiq.clqF.S. color schemeLPI color schemeInput parameters and analysis dataAnalysis method:Fines correction method:Points to test:Earthquake magnitude Mw:Peak ground acceleration:Depth to water table (insitu):NCEER (1998)NCEER (1998)Based on Ic value6.880.675.00 ftDepth to water table (erthq.):Average results interval:Ic cut-off value:Unit weight calculation:Use fill:Fill height:5.00 ft12.60Based on SBTNoN/AFill weight:Transition detect. applied:Kσ applied:Clay like behavior applied:Limit depth applied:Limit depth:N/AYesYesSands onlyYes45.02 ftAlmost certain it will liquefyVery likely to liquefyLiquefaction and no liq. are equally likelyUnlike to liquefyAlmost certain it will not liquefyVery high riskHigh riskLow riskPA2021-308
LIQUEFACTION ANALYSIS REPORT
Input parameters and analysis data
Analysis method:Fines correction method:
Points to test:Earthquake magnitude Mw:Peak ground acceleration:
NCEER (1998)NCEER (1998)Based on Ic value6.880.67
G.W.T. (in-situ):G.W.T. (earthq.):Average results interval:Ic cut-off value:Unit weight calculation:
Project title : Location :
GeoLogismiki
Geotechnical Engineers
Merarhias 56
http://www.geologismiki.gr
CPT file : CPT-3
5.00 ft5.00 ft12.60Based on SBT
Use fill:Fill height:
Fill weight:Trans. detect. applied:Kσ applied:
NoN/AN/AYesYes
Clay like behaviorapplied:Limit depth applied:Limit depth:MSF method:
Sands onlyYes22.02 ftMethod based
Cone resistance
qt (tsf)2000Depth (ft)22
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0 Cone resistance SBTn Plot
Ic (Robertson 1990)4321
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CRR & CSR 0.60.40.20
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During earthq.
Qtn,cs 200180160140120100806040200Cyclic Stress Ratio* (CSR*)0.8
0.7
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0
Liquefaction
No Liquefact ion
Normalized friction ratio (%)0.1 1 10Normalized CPT penetration resistance1
10
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1,000
Friction Ratio
Rf (%)1086420
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Mw=71/2, sigma'=1 atm base curve Summary of liquefaction potential
FS Plot
Factor of safety 21.510.50
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0 FS Plot
During earthq.
Zone A1: Cyclic liquefaction likely depending on size and duration of cyclic loading
Zone A2: Cyclic liquefaction and strength loss likely depending on loading and ground
geometry
Zone B: Liquefaction and post-earthquake strength loss unlikely, check cyclic softening
Zone C: Cyclic liquefaction and strength loss possible depending on soil plasticity,
brittleness/sensitivity, strain to peak undrained strength and ground geometry
CLiq v.3.3.1.14 - CPT Liquefaction Assessment Software - Report created on: 5/3/2021, 2:37:09 PM
Project file: V:\72450-72999\72572 (Langson) 2676 Bayshore\CPT-Liquefaction\CLiq.clq
1
PA2021-308
This software is licensed to: Stoney-Miller Consultants, IncCPT name: CPT-3Cone resistanceqt (tsf)3002001000Depth (ft)22212019181716151413121110987654321Cone resistanceCPT basic interpretation plotsFriction RatioRf (%)1086420Depth (ft)212019181716151413121110987654321Friction RatioPore pressureu (psi)6420Depth (ft)22212019181716151413121110987654321Pore pressureInsituSBT PlotIc(SBT)4321Depth (ft)212019181716151413121110987654321SBT PlotSoil Behaviour TypeSBT (Robertson et al. 1986)1817161514131211109876543210Depth (ft)22212019181716151413121110987654321Soil Behaviour TypeSensitive fine grainedSand & silty sandSand & silty sandSilty sand & sandy siltSand & silty sandSilty sand & sandy siltClaySilty sand & sandy siltSand & silty sandCLiq v.3.3.1.14 - CPT Liquefaction Assessment Software - Report created on: 5/3/2021, 2:37:09 PM2Project file: V:\72450-72999\72572 (Langson) 2676 Bayshore\CPT-Liquefaction\CLiq.clqInput parameters and analysis dataAnalysis method:Fines correction method:Points to test:Earthquake magnitude Mw:Peak ground acceleration:Depth to water table (insitu):NCEER (1998)NCEER (1998)Based on Ic value6.880.675.00 ftDepth to water table (erthq.):Average results interval:Ic cut-off value:Unit weight calculation:Use fill:Fill height:5.00 ft12.60Based on SBTNoN/AFill weight:Transition detect. applied:Kσ applied:Clay like behavior applied:Limit depth applied:Limit depth:N/AYesYesSands onlyYes22.02 ftSBT legend1. Sensitive fine grained2. Organic material3. Clay to silty clay4. Clayey silt to siltyl5. Silty sand to sandy silt6. Clean sand to silty sand7. Gravely sand to sand8. Very stiff sand told9. Very stiff fine grainedPA2021-308
This software is licensed to: Stoney-Miller Consultants, IncCPT name: CPT-3Norm. cone resistanceQtn200150100500Depth (ft)22212019181716151413121110987654321Norm. cone resistanceCPT basic interpretation plots (normalized)Norm. friction ratioFr (%)1086420Depth (ft)22212019181716151413121110987654321Norm. friction ratioNom. pore pressure ratioBq10.80.60.40.20-0.2Depth (ft)22212019181716151413121110987654321Nom. pore pressure ratioSBTn PlotIc (Robertson 1990)4321Depth (ft)212019181716151413121110987654321SBTn PlotNorm. Soil Behaviour TypeSBTn (Robertson 1990)1817161514131211109876543210Depth (ft)22212019181716151413121110987654321Norm. Soil Behaviour TypeSensitive fine grainedSand & silty sandSand & silty sandSandSand & silty sandSilty sand & sandy siltClay & silty claySand & silty sandSandSand & silty sandCLiq v.3.3.1.14 - CPT Liquefaction Assessment Software - Report created on: 5/3/2021, 2:37:09 PM3Project file: V:\72450-72999\72572 (Langson) 2676 Bayshore\CPT-Liquefaction\CLiq.clqSBTn legend1. Sensitive fine grained2. Organic material3. Clay to silty clay4. Clayey silt to siltyl5. Silty sand to sandy silt6. Clean sand to silty sand7. Gravely sand to sand8. Very stiff sand told9. Very stiff fine grainedInput parameters and analysis dataAnalysis method:Fines correction method:Points to test:Earthquake magnitude Mw:Peak ground acceleration:Depth to water table (insitu):NCEER (1998)NCEER (1998)Based on Ic value6.880.675.00 ftDepth to water table (erthq.):Average results interval:Ic cut-off value:Unit weight calculation:Use fill:Fill height:5.00 ft12.60Based on SBTNoN/AFill weight:Transition detect. applied:Kσ applied:Clay like behavior applied:Limit depth applied:Limit depth:N/AYesYesSands onlyYes22.02 ftPA2021-308
This software is licensed to: Stoney-Miller Consultants, IncCPT name: CPT-3Total cone resistanceqt (tsf)3002001000Depth (ft)22212019181716151413121110987654321Total cone resistanceLiquefaction analysis overall plots (intermediate results)SBTn IndexIc (Robertson 1990)4321Depth (ft)212019181716151413121110987654321SBTn IndexNorm. cone resistanceQtn200150100500Depth (ft)22212019181716151413121110987654321Norm. cone resistanceGrain char. factorKc109876543210Depth (ft)22212019181716151413121110987654321Grain char. factorCorrected norm. cone resistanceQtn,cs200150100500Depth (ft)22212019181716151413121110987654321Corrected norm. cone resistanceCLiq v.3.3.1.14 - CPT Liquefaction Assessment Software - Report created on: 5/3/2021, 2:37:09 PM4Project file: V:\72450-72999\72572 (Langson) 2676 Bayshore\CPT-Liquefaction\CLiq.clqInput parameters and analysis dataAnalysis method:Fines correction method:Points to test:Earthquake magnitude Mw:Peak ground acceleration:Depth to water table (insitu):NCEER (1998)NCEER (1998)Based on Ic value6.880.675.00 ftDepth to water table (erthq.):Average results interval:Ic cut-off value:Unit weight calculation:Use fill:Fill height:5.00 ft12.60Based on SBTNoN/AFill weight:Transition detect. applied:Kσ applied:Clay like behavior applied:Limit depth applied:Limit depth:N/AYesYesSands onlyYes22.02 ftPA2021-308
This software is licensed to: Stoney-Miller Consultants, IncCPT name: CPT-3CRR plotCRR & CSR0.60.40.20Depth (ft)22212019181716151413121110987654321CRR plotDuring earthq.Liquefaction analysis overall plotsFS PlotFactor of safety21.510.50Depth (ft)22212019181716151413121110987654321FS PlotDuring earthq.Liquefaction potentialLPI20151050Depth (ft)22212019181716151413121110987654321Liquefaction potentialVertical settlementsSettlement (in)0.250.20.150.10.050Depth (ft)22212019181716151413121110987654321Vertical settlementsLateral displacementsDisplacement (in)43210Depth (ft)22212019181716151413121110987654321Lateral displacementsCLiq v.3.3.1.14 - CPT Liquefaction Assessment Software - Report created on: 5/3/2021, 2:37:09 PM5Project file: V:\72450-72999\72572 (Langson) 2676 Bayshore\CPT-Liquefaction\CLiq.clqF.S. color schemeLPI color schemeInput parameters and analysis dataAnalysis method:Fines correction method:Points to test:Earthquake magnitude Mw:Peak ground acceleration:Depth to water table (insitu):NCEER (1998)NCEER (1998)Based on Ic value6.880.675.00 ftDepth to water table (erthq.):Average results interval:Ic cut-off value:Unit weight calculation:Use fill:Fill height:5.00 ft12.60Based on SBTNoN/AFill weight:Transition detect. applied:Kσ applied:Clay like behavior applied:Limit depth applied:Limit depth:N/AYesYesSands onlyYes22.02 ftAlmost certain it will liquefyVery likely to liquefyLiquefaction and no liq. are equally likelyUnlike to liquefyAlmost certain it will not liquefyVery high riskHigh riskLow riskPA2021-308
APPENDIX E
STANDARD GRADING SPECIFICATIONS
PA2021-308
APPENDIX E
STANDARD GRADING SPECIFICATIONS
GENERAL
These specifications present the usual and minimum requirements for grading operations
observed by Geofirm or its designated representative. No deviation from these specifications
will be allowed, except where specifically superseded in the geotechnical report signed by a
registered geotechnical engineer.
The placement, spreading, mixing, watering and compaction of the fills in strict accordance with
these guidelines shall be the sole responsibility of the contractor. The construction, excavation,
and placement of fill shall be under the direct observation of the soils engineer signing the soils
report. If unsatisfactory soil-related conditions exist, the soils engineer shall have the authority
to reject the compacted fill ground and, if necessary, excavation equipment will be shut down to
permit completion of compaction. Conformance with these specifications will be discussed in
the final report issued by the soils engineer.
SITE PREPARATION
All brush, vegetation and other deleterious material such as rubbish shall be collected, piled and
removed from the site prior to placing fill, leaving the site clear and free from objectionable
material.
Soil, alluvium, or rock materials determined by the soils engineer as being unsuitable for
placement in compacted fills shall be removed from the site. Any material incorporated as part
of a compacted fill must be approved by the soils engineer.
The surface shall then be plowed or scarified to a minimum depth of 6 inches until the surface is
free from uneven features that would tend to prevent uniform compaction by the equipment used.
After the area to receive fill has been cleared and scarified, it shall be diced or bladed by the
contractor until it is uniform and free from large clods, brought to the proper moisture content
and compacted to minimum requirements. If the scarified zone is greater than 12 inches in
depth, the excess shall be removed and placed in lifts restricted to 6 inches.
Any underground structures such as cesspools, cisterns, mining shafts, tunnels, septic tanks,
wells, pipe lines or others not located prior to grading are to be removed or treated in a manner
prescribed by the soils engineer.
MATERIALS
Materials for compacted fill shall consist of materials approved by the soils engineer. These
materials may be excavated from the cut area or imported from other approved sources, and soils
from one or more sources may be blended. Fill soils shall be free from organic vegetable matter
and other unsuitable substances. Normally, the material shall contain no rocks or hard lumps
PA2021-308
greater than 6 inches in size and shall contain at least 50 percent of material smaller than 1/4-
inch in size. Materials greater than 4 inches in size shall be placed so that they are completely
surrounded by compacted fines; no nesting of rocks shall be permitted. No material of a
perishable, spongy, or otherwise of an unsuitable nature shall be used in the fill soils.
Representative samples of materials to be utilized as compacted fill shall be analyzed in the
laboratory by the soils engineer to determine their physical properties. If any material other than
that previously tested is encountered during grading, the appropriate analysis of this material
shall be conducted by the geotechnical engineer as soon as possible.
PLACING, SPREADING, AND COMPACTING FILL MATERIAL
The material used in the compacting process shall be evenly spread, watered, processed and
compacted in thin lifts not to exceed 6 inches in thickness to obtain a uniformly dense layer.
When the moisture content of the fill material is below that specified by the soils engineer, water
shall be added by the contractor until the moisture content is near optimum as specified.
When the moisture content of the fill material is above that specified by the geotechnical
engineer, the fill material shall be aerated by the contractor by blading, mixing, or other
satisfactory methods until the moisture content is near optimum as specified.
After each layer has been placed, mixed, and spread evenly, it shall be thoroughly compacted to
90 percent of the maximum laboratory density in compliance with ASTM D: 1557-70 (five
layers). Compaction shall be accomplished by sheepsfoot rollers, vibratory rollers, multiple-
wheel pneumatic-tired rollers, or other types of acceptable compacting equipment. Equipment
shall be of such design that it will be able to compact the fill to the specified density.
Compaction shall be continuous over the entire area and the equipment shall make sufficient
passes to obtain the desired density uniformly.
A minimum relative compaction of 90 percent out to the finished slope face of all fill slopes will
be required. Compacting of the slopes shall be accomplished by backrolling the slopes in
increments of 2 to 5 feet in elevation gain or by overbuilding and cutting back to the compacted
inner core, or by any other procedure which produces the required compaction.
OBSERVATIONS AND TESTING
The geotechnical engineer shall observe the placement of fill during the grading process and will
file a written report upon completion of grading stating his observations as to compliance with
these specifications.
One density test shall be required for each 2 vertical feet of fill placed, or one for each 1,000
cubic yards of fill, whichever requires the greater number of tests.
PA2021-308
Any cleanouts and processed ground to receive fill must be observed by the soils engineer and/or
engineering geologist prior to any fill placement. The contractor shall notify the geotechnical
engineer when these areas are ready for observation.
PROTECTION OF WORK
During the grading process and prior to the complete construction of permanent drainage
controls, it shall be the responsibility of the contractor to provide good drainage and prevent
ponding of water and damage to adjoining properties or to finished work on the site.
After the geotechnical engineer has terminated his observations of the completed grading, no
further excavations and/or filling shall be performed without the approval of the soils engineer, if
it is to be subject to the recommendations of this report.
PA2021-308
APPENDIX F
UTILITY TRENCH BACKFILL GUIDELINES
PA2021-308
APPENDIX F
UTILITY TRENCH BACKFILL GUIDELINES
The following guidelines pertinent to utility trench backfills have been adopted by the County of
Orange, Environmental Management Agency Grading Section, effective March 31, 1986. The
application of the guidelines is strictly enforced by the County reviewers and inspectors.
1. Each utility subcontractor (gas, electric, water, sewer, telephone, cable TV, irrigation,
drainage, etc.) shall submit to the developer for dissemination to his consultants (civil
engineer, geotechnical engineer, and utility contractor) a plot plan of utility lines installed
under his purview which identifies line type, material, size, depth, and approximate
location.
2. The developer or his agent shall provide a composite plot plan of all utilities or a copy of
all individual utility plot plans to his geotechnical engineer for use in evaluating whether
all utility trench backfills are suitable for the intended use.
3. The geotechnical engineer shall provide the County with a report which includes a plot
plan showing the location of all utility trenches which:
A. Are located within the load influence zone of a structure (1:1 projection)
B. Are located beneath any hardscape
C. Are parallel and in close proximity to the top or toe of a slope and may adversely
impact slope stability if improperly backfilled
D. Are located on the face of a slope in a trench 18 or more inches in depth.
Typically, trenches that are less than 18 inches in depth will not be within the load
influence zone if located next to a structure, and will not have a significant effect on
slope stability if constructed near the top or toe of a slope and need not be shown on the
plot plan unless determined to be significant by the geotechnical engineer. This plot plan
may be prepared by someone other than the soil engineer, but must meet his approval.
4. Backfill compaction test locations must be shown on the plot plan described in No. 3
above, and a table of test data provided in the geotechnical report.
5. The geotechnical report (utility trench backfill) must state that all utility trenches within
the subject lots have been backfilled in a manner suitable for the intended use. This
includes the backfill of all trenches shown on the plot plan described in No. 3 and the
backfill of those trenches which did not need to be plotted on this plan.
PA2021-308