HomeMy WebLinkAboutPA2022-0295_20221205_Geotechnical Investigation Report dated 10-18-22COAST GEOTECHNICAL, INC.
Geotechnical Engineering Investigation
of
Proposed New Residence
at
6104 West Ocean Front
Newport Beach, California
BY:
COAST GEOTECHNICAL, INC.
W. 0. 644322-01, October 18, 2022
FOR:
Mr. and Mrs. Chase Sanderson
6104 West Ocean Front
Newport Beach, CA 92663
PA2022-0295
COAST GEOTECHNICAL, INC.
1200 W. Commonwealth Avenue. Fullerton. CA 92833 ■ Ph: (714) 870-1211 ■ Fax: (714) 870-1222 ■ E-mail:coastgeotec@sbcglobal.net
October 18, 2022
Mr. and Mrs. Chase Sanderson
6104 West Ocean Front
Newport Beach, CA 92663
Dear Mr. and Mrs. Sanderson:
Subject:
w.o. 644322-01
Geotechnical Engineering Investigation of
Proposed New Residence at 6104 West
Ocean Front, Newport Beach, California
Pursuant to your request, a geotechnical engineering investigation has been performed at the subject
site. The purposes of the investigation were to determine the general engineering characteristics of
the near surface soils on and underlying the site and to provide recommendations for the design of
foundations and underground improvements.
The conclusions and recommendations contained in this report are based upon the understanding of
the proposed development and the analyses of the data obtained from our field and laboratory
testing programs.
This report completes our scope of geotechnical engineering services authorized by you in the
August 23, 2022 proposal.
SITE DEVELOPMENT
It is our understanding that the existing residence will be demolished and that the site is to be
redeveloped with a two or three story residential structure over slab on grade. Structural loads are
anticipated to be light.
PURPOSE AND SCOPE OF SERVICES
The scope of the study was to obtain subsurface information within the project site .area and to
provide recommendations pertaining to the proposed development and included the following:
1. A cursory reconnaissance of the site and surrounding areas.
2. Excavation of two exploratory borings to determine the near subsurface soil conditions and
groundwater conditions.
3. Collection of representative bulk and/or undisturbed soil samples for laboratory analysis.
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
2 w. 0. 644322-01
October 18, 2022
4. Laboratory analyses of soil samples including determination of in-situ and maximum density, in-
situ and optimum moisture content, shear strength characteristics, consolidation and expansion
potential, and sulfate content.
5. Preparation of this report presenting results of our investigation and recommendations of the
proposed development.
SITE CONDITIONS
The project site is located at 6104 West Ocean Front, in the City of Newport Beach, California, and
is shown on the attached Site Vicinity Map, Plate 1.
The parcel is near rectangular in shape, near level, and bordered by West Ocean Front and
residential properties.
The lot is currently developed with a single-family residence, landscape and hardscape. Site
c9nfiguration is further shown on the Site Plan, provided by OHA Construction, Plate 2.
RECORDS REVIEW
A search of records was performed through the City of Newport Beach online database for
applicable geotechnical records for the lot and tract. This parcel is part of Lot 3 of Tract Seashore
Colony and documents recording earth work for this location were found. Some of the pages from
the reports reviewed are attached in Appendix D.
A Preliminary Soils Investigation Report was completed for the subject site, by Sladden
Engineering on December 16, 1996.
"The preliminary report was performed in order to provide recommendations for the design and
construction of the proposed residential building. The proposed residence will include two main
stories , and a loft. The residence will be of wood-frame construction and will be supported by
conventional shallow spread footings.
Two exploratory borings were excavated using a truck mounted hollow stem auger rig and drilled
to 41.5 and 51.5 feet in depth."
A Compaction Report for the Building Pad at the subject site was completed by Geo-ETKA, INC
on February 17, 1997.
"The following report contains the results of the Sand Cone Denisty Test Methods A.S. T.M D-
1556, and/or Nuclear Density Test Methods D-2922 and D-3017, Test numbers 1 through 13, taken
on the subject project.
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
3 w. 0. 644322-01
October 18, 2022
The building pad was subexcavated to a firm soil such as to provide a minimum of 4 feet of
compacted soil as required. It is recommended that the slab on grade be at least 4 inches thick ...
and underlain by a moisture barrier ... "
A Summary and Final Report was completed for the subject site by Geo-ETKA, INC on January
26, 1998. The report lists all previous work and reports completed at the subject site.
"The following is a summary of the reports prepared for this project. The structure is nearly
complete. This is a final report. "
The previous reports as stated are, "Preliminary soil exploration report, Compaction report for the
building pad, Footing excavation, interior sewer at pad grade testing, and exterior utility trench
baclifi,ll and jlatwork area testing"
Readers of this report are advised that a record· search is not an exact science; it is limited by time
and resource constraints, incomplete records, ability of custodian of records to locate files, and
where records are located is only a limited interpretation of other consultant's work. Readers of this
report should perform their own review of City records to arrive at their own interpretations and
conclusions.
EXPLORATORY PROGRAM
The field investigation was performed on September 27, 2022, consisting of the excavation of a
boring by a limited access drilling equipment (for Boring No. 1) and a boring by hand auger
equipment (for Boring No. 2) at the locations shown on the attached Topographic Survey Plan,
Plate 2. As excavations progressed, a representative from this office visually classified the earth
material encountered, and secured representative samples for laboratory testing.
Geotechnical characteristics of subsurface conditions were assessed by either driving a split spoon
ring sampler or an SPT sampler into the earth material.
Undisturbed samples for detailed testing in our laboratory were obtained from Boring No. 2 by
pushing or driving a sampling spoon into the earth material. A solid-barrel type spoon was used
having an inside diameter of 2.5 inches with a tapered cutting tip at the lower end and a ball valve
at the upper end.
The barrel is lined with thin brass rings, each one inch in length. The spoon penetrated into the earth
materials below the depth of borings approximately six inches a 35# slide hammer. The central
portion of this sample was retained for testing. All samples in their natural field condition were
sealed in airtight containers and transported to the laboratory.
Standard Penetration Test (SPT) was performed for Boring No. 1, based on ASTM D1586. The
number of blows required for driving the sampler through three six-inch intervals is recorded. The
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
4 w. 0. 644322-01
October 18, 2022
sum of the number of blows required for driving the last two six-inch intervals is referred to as the
standard penetration number "N".
Samplers from Boring No. 1 were driven into the soil at the bottom of the borehole by means of
hammer blows. The hammer blows are given at the top of the drilling rod. The blows are by a
hammer weighing 140 pounds dropped a distance of 30 inches. Drive sampling was obtained at two
feet intervals for the upper level foundations in accordance with City guidelines. Considering that
the upper three feet of the pad area will be recompacted, SPT sampling commenced at three feet
below grade.
For liquefaction analysis, CE of 1.0 (for safety hammer), CB of 1.05 (for seven inch borehole
diameter), and Cs of 1.2 (for sampler without liners) are used to calculate corrected N values.
EARTH MATERIALS
Earth materials encountered within the exploratory borings were visually logged by a representative
of COAST GEOTECHNICAL, Inc. The earth materials encountered were classified as artificial fill
underlain by native soils to the maximum depth explored.
Artificial fills encountered consisted of slightly silty, fine to medium-grained sand, brown and tan
brown in color, damp, and generally loose. The fills were encountered to a depth of about 1.5 to 2.0
feet below existing grade.
Native soils encountered consisted of clean to slightly silty, fine to coarse-grained sand, tan and
light gray tan to light gray, damp to wet and generally medium dense, to maximum depth explored
of 12.5 feet.
Logs of the exploratory borings are presented on the appended Plates B and C.
GROUNDWATER
Groundwater was encountered at about seven to eight feet below existing ground surface in the
borings during the field investigation. This groundwater level is subject to minor fluctuation due to
tidal changes. Plate 1.2 in Appendix B shows the subject site area to have a historic high
groundwater depth of less than ten feet below existing ground surface. In our liquefaction and
seismic settlement analyses, a groundwater elevation of five feet below ground surface is used for
more conservative calculations in accordance with City policy.
SEISMICITY
Southern California is located in an active seismic region. Moderate to strong earthquakes can
occur on numerous faults. The United States Geological Survey, California Division of Mines and
Geology, private consultants, and universities have been studying earthquakes in
Southern California for several decades. Early studies were directed toward earthquake prediction
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
5 w. 0. 644322-01
October 18. 2022
estimation of the effects of strong ground shaking. Studies indicate that earthquake prediction is not
practical and not sufficiently accurate to benefit the general public. Governmental agencies are
shifting their focus to earthquake resistant structures as opposed to prediction. The purpose of the
code seismic design parameters is to prevent collapse during strong ground shaking.
Cosmetic damage should be expected.
Within the past 51 years, Southern California and vicinity have experienced an increase in seismic
activity beginning with the San Fernando earthquake in 1971. In 1987, a moderate earthquake
struck the Whittier area and was located on a previously unknown fault. Ground shaking from this
event caused substantial damage to the City of Whittier, and surrounding cities. The
January 17, 1994, Northridge earthquake was initiated along a previously unrecognized fault below
the San Fernando Valley. The energy released by the earthquake propagated to the southeast,
northwest, and northeast in the form of shear and compression waves, which caused the strong
ground shaking in portions of the San Fernando Valley, Santa Monica Mountains, Simi Valley,
City of Santa Clarita, and City of Santa Monica.
The numerous faults in Southern California include Holocene active, pre-Holocene active, and
inactive faults. The criteria for these major groups are based on criteria developed by the
California Geological Survey (formerly known as California Division of Mines and Geology) for
the Alquist-Priolo Earthquake Fault Zone Program. By definition, a Holoceneactive fault is one
that has had surface displacement within Holocene time (about the last 11,700 years). A pre-
Holocene fault has demonstrated surface displacement during Quaternary time (approximately
the last 1.6 million years), but has had no known Holocene movement. Faults that have not
moved in the last 1.6 million years are considered inactive.
The site is not within a state-designated Alquist-Priolo Earthquake Fault Zone for Holocene
surface fault rupture hazards. Nearby causative faults are as follows.
• Newport-Inglewood Fault Zone: The Newport-Inglewood Fault Zone is a broad zone of left-
stepping en echelon faults and folds striking southeastward from near Santa Monica across the
Los Angeles basin to Newport Beach. Altogether these various faults constitute a system more
than 150 miles long that extends into Baja California, Mexico. Faults having similar trends and
projections occur offshore from San Clemente and San Diego (the Rose Canyon and La Nacion
Faults). A near-shore portion of the Newport-Inglewood Fault Zone was the source of the
destructive 1933 Long Beach earthquake. The reported recurrence interval for a large event along
this fault zone is 1,200 to 1,300 years with an expected slip of one meter.
• San Joaquin Hills Blind Thrust Fault: The seismic hazards in Southern California have been
further complicated with the recent realization that major earthquakes can occur on large thrust
faults that are concealed at depths between 5 to 20 km, referred to as "blind thrusts." The uplift
of the San Joaquin Hills is produced by a southwest dipping blind thrust fault that extends at
least 14 km from northwestern Huntington Mesa to Dana Point and comes to within 2 km of the
ground surface. Work by Grant et al. (1997 and 1999) suggest that uplift of the San Joaquin Hills
began in the Late Quaternary and continues during the Holocene. Uplift rates have been
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
6 w. 0. 644322-01
October 18, 2022
estimated between 0.25 and 0.5 mm/yr. If the entire length of the fault ruptured, the earthquake
has been estimated to generate an Mw 6.8 event.
We are of the opinion that the more active Newport Inglewood fault is the causative fault for the
subject site. The site is located within approximately one kilometer northeast of the Newport
Inglewood fault.
SEISMIC HAZARDS
The potential hazards to be evaluated with regard to seismic conditions include fault rupture,
landslides triggered by ground shaking, soil liquefaction, earthquake-induced vertical and lateral
displacements, earthquake-induced flooding due to the failure of water containment structures,
seiches, and tsunamis.
Fault Rupture
The project is not located within a currently designated Alquist-Priolo Earthquake Zone (Bryant
and Hart, 2007). No known active faults are mapped on the site. Based on this consideration, the
potential for surface fault rupture at the site is considered to be remote.
Ground Shaking
The site is located in a seismically active area that has historically been affected by moderate to
occasionally high levels of ground motion, and the site lies in relatively close proximity to
several active faults; therefore, during the life of the proposed development, the property will
probably experience moderate to occasionally high ground shaking from these fault zones, as
well as some background shaking from other seismically active areas of the Southern California
region. Residential structures are typically designed to maintain structural integrity not to prevent
damage. Earthquake insurance is available where the damage risk is not acceptable to the client.
Seismic Induced Landslide
Earthquake-induced landslide zones were delineated by the State of California using criteria
adopted by the California State Mining and Geology Board. Under those criteria, earthquake-
induced landslide zones are areas meeting one or more of the following:
1. Areas known to have experienced earthquake-induced slope failure during historic earthquakes.
2. Areas identified as having past landslide movement, including both landslide deposits and source
areas.
3. Areas where CDMG's analyses of geologic and geotechnical data indicate that the geologic
materials are susceptible to earthquake-induced slope failure.
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
7 w. 0. 644322-01
October 18, 2022
Based on the Seismic Hazard Zone Map published by the State of California, Newport Beach
Quadrangle, appended as Plate 3, the site is not mapped as being in an area subject to potential
seismic induced landslides.
Seismic Induced Liquefaction
Liquefaction is a seismic phenomenon in which loose, saturated, non-cohesive granular soils
exhibit severe reduction in strength and stability when subjected to high-intensity ground
shaking. The mechanism by which liquefaction occurs is the progressive increase in excess pore
pressure generated by the shaking associated with the seismic event and the tendency for loose
non-cohesive soils to consolidate. As the excess pore fluid pressure approaches the in-situ
overburden pressure, the soils exhibit behavior similar to a dense fluid with a corresponding
significant decrease in shear strength and increase in compressibility. Liquefaction occurs when
three general conditions exist: 1) shallow groundwater; 2) low density, non-cohesive sandy soils;
and 3) high-intensity ground motion.
Seismic Hazard Zone Maps published by the State of California have been prepared to indicate
areas that have a potential for seismic induced liquefaction hazards. The Seismic Hazard Zone
Map for the Newport Beach Quadrangle, appended as Plate 3, shows the site to be mapped as
being subject to potential liquefaction hazards.
The City of Newport Beach has a policy concerning these areas. The City has assigned certain
parameters to existing soil conditions. From ten to thirty feet below ground surface they have
assigned the zone to be liquefiable with a seismic settlement of three inches. From thirty to fifty
feet below ground surface they have assigned liquefaction and seismic settlement not to be of
concern. The client has the option of accepting these conditions and assessing the zone of earth
materials from the ground surface to ten feet below the proposed footing bottom for liquefaction
and seismic settlement, or ignoring the City conditions and drilling deep exploration for similar
assessment.
For this project shallow exploration was chosen. A liquefaction assessment for the upper earth
materials follows.
Liquefaction evaluation for soil zone to ten feet below foundation bottom was based on blow
counts from Boring No. 1, a M = 7.2 seismic event from the Newport-Inglewood fault, a
maximum ground acceleration of 0.731g PGAM and a groundwater level at five feet.
Liquefaction analysis, based on these values and field obtained data, is presented in Appendix B.
The results indicate that there is liquefaction potential for the subject site, unlike what was
presented in the Preliminary Soils Investigation completed in 1996, by Sladden Engineering.
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
Lateral Spreading
8 w. 0. 644322-01
October 18, 2022
The occurrence of liquefaction may cause lateral spreading. Lateral spreading is a phenomenon in
which lateral displacement can occur on the ground surface due to movement of non-liquefied
soils along zones of liquefied soils. For lateral spreading to occur, the liquefiable zone must be
continuous, unconstrained laterally, and free to move along sloping ground toward an unconfined
area.
Due to the relatively level lot and distance to a free face, the potential of lateral spreading is not
considered to be significant.
Earthquake-induced Settlements
Earthquake-induced settlements result from densification of non-cohesive granular soils which
occur as a result of reduction in volume during or after an earthquake event. The magnitude of
settlement that results from the occurrence of liquefaction is typically greater than the settlement
that results solely from densification during strong ground shaking in the absence of liquefaction.
It is understanding that the current City policy, has assigned a seismic settlement potential of
three inches for soil depths of ten to thirty feet and no additional analysis of seismic settlement
for this level should be required.
The seismically induced settlement was evaluated based on the "Evaluation of Settlements in
Sand Deposits Following Liquefaction During Earthquakes" by Kenji Ishihara and Mitsutoshi
Yoshimine, dated March 1992. The analysis was limited to ten feet below the footing bottom.
The result, based on the SPT N-values in Boring No. 1, groundwater table at five feet below
ground surface and shown in Appendix C, indicates that the estimated settlement is 0.71 inch.
According to City policy, the City's shallow mitigation method may be used since the seismic
settlement is less than one inch to a depth of ten feet below proposed foundations.
Earthquake-Induced Flooding
The failure of dams or other water-retaining structures as a result of earthquakes and strong
ground shaking could result in the inundation of adjacent areas. Due to the lack of a major dam
or water-retaining structure located near the site, the potential of earthquake-induced flooding
affecting the site is considered not to be present.
Seiches
Seiches are waves generated in enclosed bodies of water in response to ground shaking. Based on
the lack of nearby enclosed bodies of water the risk from a seiche event is not present.
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
Tsunamis
9 w. 0. 644322-01
October 18, 2022
Tsunamis are waves generated in large bodies of water as a result of change of seafloor topography
caused by tectonic displacement or landslide.
Based on the City of Newport Beach "Potential Tsunami Runup Inundation Caused by a Submarine
Landslide" map, the subject site is situated in the zone for potential tsunami run-up as shown on
Plate 5, and is referenced on this plate to be areas below elevation 32 feet. For more information
about tsunami run-up hazards and evacuation routes you are referred to the City website.
GEOTECHNICAL DISCUSSION
The site is within an area subject to liquefaction and liquefaction induced settlements under certain
seismic events. Under current CBC codes, City policy, and industry standards residential structures
subject to seismic hazards are designed to protect life and safety. Under this design objective the
requirements of protecting life and safety could be met but the structure could be damaged. The
damage to the structure could range from minimal to being non-functional. The reduction of risk,
for the occurrence of structural damage from a seismic event, is generally associated with the
structure's foundation system.
Typically the use of a conventional foundation system or a mat foundation system has been utilized
in the area. Based on site conditions, our recommendation is that the proposed residence be
supported by a structural mat foundation system. A structural mat foundation is more rigid than
conventional foundations, and should be more effective in mitigation of structural damage to a
residence during a seismic event.
If the risk associated with this foundation system is not acceptable to the client, the client has the
option of utilizing alternate designs that could decrease the risk of damage to the structure to a level
they perceive as acceptable. Some of these designs could consist of soil modifications, grout
densification, stone columns, piles placed below liquefiable soils, and other methods. Additional
geotechnical exploration and or analysis would be required to provide geotechnical design
recommendation for these mitigation measures, and would be at the request of the client under
separate contract.
Development of the site as proposed is considered feasible from a soils engineering standpoint,
provided that the recommendations stated herein are incorporated in the design and are
implemented in the field. The proposed grading and or construction will not have an adverse effect
on adjacent property or vice versa, provided site work is performed in accordance with the
guidelines of project geotechnical reports, approved plans, applicable codes, industry standards,
City inspections, and required geotechnical observation and testing.
The following recommendations are subject to change based on review of final foundation and
grading plans.
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
PROPOSED GRADING
10 w. 0. 644322-01
October 18, 2022
Grading plans were not available at the time this report was prepared. It is anticipated that grading
will consist mainly of over-excavation and recompaction for uniform support of the foundations
and slabs.
GENERAL GRADING NOTES
All existing structures shall be demolished and all vegetation and debris shall be stripped and
hauled from the site. The entire grading operation shall be done in accordance with the attached
"Specifications for Grading".
Any import fill materials to the site shall not have an expansion index greater than 20, and shall be
tested and approved by our laboratory. Samples must be submitted 48 hours prior to import.
Grading and/or foundation recommendations are subject to modification upon review of final plans
by the Geotechnical Engineer. Please submit plans to COAST GEOTECHNICAL, Inc. when
available.
GRADING RECOMMENDATIONS
Removal and recompaction of existing earth materials will be required to provide adequate
support for foundations and site improvements. Earthwork for foundation support shall include
the entire building pad and shall extend a minimum of three feet outside exterior footing lines.
Based on in place densities and consolidation tests, soils found at a depth of three feet below
existing grade and deeper have adequate geotechnical properties to provide adequate support of
proposed fills and the structure; as such, removals to a depth of three feet below existing grade or to
one foot below proposed footing bottoms, whichever is greater, are anticipated; however, field
observations made at the time of grading shall determine final removal limits.
To provide adequate support along property lines excavations shall be sloped at a 1:1 (H:V)
gradient from property line down to the excavation bottom. As fill soils are placed the grading
contractor shall bench into the 1: 1 construction cut to final grade. Temporary excavations along
property lines are shown on Plate 4.
During earthwork operations, a representative of COAST GEOTECHNICAL, INC. shall be present
to verify compliance with these recommendations. Subsequent to approval of the excavation
bottom, the area shall be scarified six inches, mixed with Portland cement, moisture conditioned
as needed, and compacted to a minimum of 90% relative compaction.
Fill soils shall be placed in six to eight inch loose lifts, moisture conditioned as needed, and
compacted to a minimum of 90% relative compaction. This process shall be utilized to finish
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
11 w. 0. 644322-01
October 18, 2022
grade. Due to the caving nature of the on-site sands, it is highly recommended that all fill soils be
mixed with Portland cement to mitigate the potential for caving of the foundation excavations.
Grading for hardscape areas shall consist of removal and recompaction of loose surficial soils.
Removal depths are estimated at one to two feet. Earthwork shall be performed in accordance
with previously specified methods.
FOUNDATIONS -RESIDENCE
The residence shall be supported by a mat foundation.
The mat foundation may utilize an allowable bearing value of 1,800 pounds per square foot. This
value is for dead plus live load and may be increased by 1/3 for total including seismic and wind
loads where allowed by code. Calculations are provided on Plate G. The structural engineer's
reinforcing requirements should be followed if more stringent.
The structural engineer should design the thickness and reinforcement requirements for the mat
foundation for the building based on the anticipated loading conditions. The mat foundation slab
should be at least twelve inches thick, with perimeter footing a minimum of 24 inches below the
lowest adjacent grade. A modulus of subgrade reaction of 100 pci may be used in the design of
· the mat foundation. Calculations are provided on Plate I. Reinforcement shall be determined by
the structural engineer.
Alternate foundations and or additional ground modification techniques, for support of the
structure, can be addressed upon request of the project manager. All foundation plans are subject
to review and approval of the soils engineer.
All foundation bottoms shall be observed and approved by COAST GEOTECHNICAL, Inc.
prior to placement of the capillary break.
FOUNDATIONS-SECONDARY STRUCTURES
Property line walls, planter walls, and other incidental foundations may utilize conventional
foundation design.
Continuous spread footings or isolated pads placed a minimum depth of 24 inches below lowest
adjacent grade may utilize an allowable bearing value of 1,500 pounds per square foot. This
value is for dead plus live load and may be increased 1/3 for total including seismic and wind
loads where allowed by code.
Where isolated pads are utilized, they shall be tied in two directions into adjacent foundations
with grade beams.
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
12 w. 0. 644322-01
October 18, 2022
Footing excavations shall be observed by a representative of COAST GEOTECHNICAL, Inc.,
prior to placement of steel or concrete to verify competent soil conditions. If unacceptable soil
conditions are exposed mitigation will be recommended.
Foundations shall be reinforced with a minimum of four #5 bars, two top and two bottom, The
structural engineer's recommendations for reinforcement shall be utilized where more severe.
LATERAL DESIGN
Lateral restraint at the base of footings and on slabs may be assumed to be the product of the dead
load and a coefficient of friction of 0.35. Passive pressure on the face of footings may also be used
to resist lateral forces. A passive pressure of zero at the surface of finished grade, increasing at the
rate of 300 pounds per square foot of depth to a maximum value of 3,000 pounds per square foot,
may be used for compacted fill at this site. Calculations are provided on Plate H. If passive pressure
and friction are combined when evaluating the lateral resistance, then the value of the passive
pressure should be limited to 2/3 of the values given above.
FLOOR SLABS
Due to liquefaction potential at the subject site, it is recommended that a mat foundation be used
for the proposed structure. The minimum thickness of the mat slab is twelve inches.
Slab on grades shall be designed in accordance with current CBC codes.
Site soils are non-plastic.
Slab on grade areas shall be supported on engineered fill compacted to a minimum of 90%
relative compaction and exhibiting proper moisture content. Subgrade soil should be kept moist
prior to casting the slab. However, if the soils at grade become disturbed during construction,
they should be brought to approximately optimum moisture content and rolled to a firm,
unyielding condition prior to placing concrete. COAST GEOTECHNICAL, Inc. to verify
adequacy of sub grade spoils prior to placement of vapor barrier or capillary break.
Section 4.505.2.1 of the California Green Code requires the use of a capillary break between the
slab subgrade and vapor barrier. The capillary break material shall comply with the requirements
of the local jurisdiction and shall be a minimum of four inches in thickness. Geotechnically
coarse clean sand is acceptable; however, some localities require the use of four inches of gravel
(1/2-inch or larger clean aggregate). If gravels are used, a heavy filter fabric (Mirafi 140N) shall
be placed over the gravels prior to placement of the recommended vapor barrier to minimize
puncturing of the vapor barrier. Additionally, a vibratory plate should be used over the gravels
prior to placement of the recommended filter fabric to smooth out any sharp protuberances and
consolidate the gravels.
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
13 w. 0. 644322-01
October 18, 2022
Slab areas should be underlain by a vapor retarder consisting of an engineered plastic film ( as
described by ASTM:E-1745). In areas where a moisture sensitive floor covering will be used
and/or where moisture infiltration is not desirable, a vapor barrier with a permeance of less than
0.0lperms (consistent with ACI 302.2R-06) such as 15 mil. Stego Wrap Vapor Barrier, or
equivalent, should be considered, and a qualified water proofing specialist should be consulted.
The vapor barrier should be underlain by the above described capillary break materials and filter
cloth. The capillary break materials should be compacted to a uniform condition prior to
placement of the recommended filter cloth and vapor barrier. The vapor barrier should be
properly lapped and sealed.
SEISMIC DESIGN
Based on the current CBC and ASCE7-16, the following seismic design parameters are provided.
These seismic design values were determined utilizing latitude 33.62552 and longitude -117.94917
and calculations from the SEAOC/OSHPD Seismic Design Tool. Data output is attached in
Appendix B. A site class D-Default was assigned to site earth materials.
• Site Class= D-Default
• Mapped 0.2 Second Spectral Response Acceleration, Ss = 1.394g
• Mapped One Second Spectral Response Acceleration S1 = 0.499g
• Site Coefficient from Table 1613A5.3(1), Fa= 1.2
• Site Coefficient from Table 1613A5.3(2), Fv = 1.801
• Maximum Design Spectral Response Acceleration for short period, SMs = 1.672g
• Maximum Design Spectral Response Acceleration for one-second period, SM1 = 0.899g
• 5% Design Spectral Response Acceleration for short period, Sos= 1.115g
• 5% Design Spectral Response Acceleration for one-second period, S01 = 0.599g
The Fv, SM1, and S01 are calculated based on Table 11.4-2 of ASCE7-16 as shown on Plate X.
Since S1 is more than 0.2, the project structural engineer shall perform required calculations to
make sure that a site response analysis is not required according to 11.4.8 of ASCE7-16.
SETTLEMENT
The maximum total post-construction static settlement is anticipated to be on the order of 1/2 inch.
Differential settlements are expected to be less than 1/2 inch, measured between adjacent structural
elements over a distance of 40 feet. Seismic induced settlements are addressed under previous
sections.
SUBSIDENCE & SHRINKAGE
Subsidence over the site is anticipated to be negligible. Shrinkage of reworked materials should be
in the range of 5 to 10 percent.
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
EXPANSIVE SOILS
14 w. 0. 644322-01
October 18. 2022
Results of expansion tests indicate that the near surface soils have a very low expansion potential.
UTILITY LINE BACKFILLS
All utility line backfills, both interior and exterior, shall be compacted to a rrurumum of
90% relative compaction and shall require testing at a maximum of two-foot vertical intervals.
Utility lines shall be placed at appropriate depths. Shallow pipes can be damaged by the forces
imposed by compacting backfill soils. If shallow pipes are not capable of withstanding the forces of
backfill compaction, slurry backfill will be recommended.
HARDSCAPE AND SLABS
Hardscape and slab subgrade areas shall exhibit a minimum of 90% relative compaction to a depth
of at least one foot. Deeper removal and recompaction may be required if unacceptable conditions
are encountered. These areas require testing just prior to placing concrete. Hardscape shall be at
least four inches thick and reinforced with #3 bars on 18 inch centers both ways.
CHEMICAL ANALYSIS
An on-site soil sample showed a soluble sulfate content of 68 ppm, which is a negligible sulfate
exposure. Concrete with Type II 2,500 psi may be utilized; however, the saltwater environ may
cause damage to exposed concrete and a designed concrete should be considered.
DRAINAGE
Positive drainage should be planned for the site. Drainage should be directed away from structures
via non-erodible conduits to suitable disposal areas. The structure should utilize roof gutters and
down spouts tied directly to yard drainage.
Pipes used for storm/site water drainage should be stout enough to withstand the force of
compaction of the soils above. This force can be considerable, causing some weaker pipes to
collapse. Drainage pipes shall have a smooth interior. Pipes with a corrugated interior can cause the
buildup of deleterious matter, which can impede or block the flow of site waters and, as such, are
not recommended. All storm/site water drainage pipes should be in conformance with the
requirements of Table 1102.5 of the California Plumbing Code.
Unlined flowerbeds, planters, and lawns should not be constructed against the perimeter of the
structure. If such landscaping ( against the perimeter of a structure) is planned, it should be properly
drained and lined or provided with an underground moisture barrier. Irrigation should be kept to a
rmmmum.
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
15 w. 0. 644322-01
October 18, 2022
The current CBC recommends five percent slope away from structures for landscape areas within
ten feet of the residence. Hardscape areas shall be sloped a minimum of two percent where within
ten feet of the residence unless allowed otherwise by the building official. Minimum drainage shall
be one percent for hardscape areas and two percent for all other areas.
We do not recommend the use of infiltration best management practice (BMP) such as bottomless
trench drains, infiltration trenches, infiltration basins, dry wells, permeable pavements or similar
systems designed primarily to percolate water into the subsurface soils within five feet of
foundations. Due to the physical characteristics of the site earth materials, infiltration of waters into
the subsurface earth materials has a risk of adversely affecting below grade structures, building
foundations and slabs, and hardscape improvements. From a geotechnical viewpoint surface
drainage should be directed to the street.
The WQMP requirement shall be addressed by the Civil Engineer.
ENGINEERING CONSULTATION, TESTING & OBSERVATION
We will be pleased to provide additional input with respect to foundation design once methods of
construction have been determined.
Grading and foundation should be reviewed by this office prior to commencement of grading so
that appropriate recommendations, if needed, can be made.
Areas to receive fill should be observed when unsuitable materials have been removed and prior to
placement of fill. Fill should be observed and tested for compaction as it is placed.
SUPPLEMENTAL CONSULTING
During construction, a number of reviews by this office are recommended to verify site
geotechnical conditions and conformance with the intentions of the recommendations for
construction. Although not all possible geotechnical observation and testing services are required.
The following site reviews are advised, some of which will probably be required by the City of
Newport Beach:
• Grading and excavations review for main structures
• Foundation excavations
• Slab sub grade compaction testing prior to placement of the capillary break or waste slab
• Slab steel placement, primary and appurtenant structures
• Compaction of interior and exterior utility trench backfill
• Hardscape subgrade compaction
AGENCY REVIEW
All soil, geologic and structural aspects of the proposed development are subject to the review and
approval of the governing agency(s). It should be recognized that the governing agency(s) can
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
16 w. 0. 644322-01
October 18, 2022
dictate the manner in which the project proceeds. They could approve or deny any aspect of the
proposed improvements and/or could dictate which foundation and grading options are acceptable.
Supplemental geotechnical consulting in response to agency requests for additional information
could be required and will be charged on a time and materials basis.
LIMITATIONS
This report presents recommendations pertaining to the subject site based on the assumption that
the subsurface conditions do not deviate appreciably from those disclosed by our exploratory
excavations. Our recommendations are based on the technical information, our understanding of the
proposed construction, and our experience in the geotechnical field. We do not guarantee the
performance of the project, only that our engineering work and judgments meet the standard of care
of our profession at this time.
In view of the general conditions in the area, the possibility of different local soil conditions may
exist. Any deviation or unexpected condition observed during construction should be brought to the
attention of the Geotechnical Engineer. In this way, any supplemental recommendations can be
made with a minimum of delay necessary to the project.
If the proposed construction will differ from our present understanding of the project, the existing
information and possibly new factors may have to be evaluated. Any design changes and the
finished plans should be reviewed by the Geotechnical Consultant. Of particular importance would
be extending development to new areas, changes in structural loading conditions, postponed
development for more than a year, or changes in ownership.
This report is issued with the understanding that it is the responsibility of the owner, or of his
representative, to ensure that the information and recommendations contained herein are called to
the attention of the Architects and Engineers for the project, and incorporated into the plans and that
the necessary steps are taken to see that the contractors and subcontractors carry out such
recommendations in the field.
This report is subject to review by the controlling authorities for this project.
We appreciate this opportunity to be of service to you.
Respectfully submitted:
COAST GEOTECHNICAL, INC.
~':"f"-t
Ming-Tarng Chen
RCE 54011
#&f~
Robert C. Langhurst
Staff Geologist
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
17
APPENDIX A
w. 0. 644322-01
October 18, 2022
This appendix contains a description of the field investigation, laboratory testing procedures and
results, site plan, exploratory logs and expansive soil recommendations.
FIELD INVESTIGATION
The field investigation was performed on September 27, 2022, consisting of the excavation of a
boring by a limited access drilling equipment (for Boring No. 1) and a boring by hand auger
equipment (for Boring No. 2) at the locations shown on the attached Site Plan, provided by OHA
Construction, Plate 2. As drilling progressed, personnel :from this office visually classified the soils
encountered, and secured representative samples for laboratory testing.
Description of the soils encountered is presented on the attached Boring Logs. The data presented
on this log is a simplification of actual subsurface conditions encountered and applies only at the
specific boring location and the date excavated. It is not warranted to be representative of
subsurface conditions at other locations and times.
LABORATORY TESTING
Field samples were examined in the laboratory and a testing program was then established to
develop data for preliminary evaluation of geotechnical conditions.
Field moisture and dry densities were calculated for each undisturbed sample. The samples were
obtained per ASTM:D-2937 and tested under ASTM:D-2216.
Maximum density-optimum moisture relationships were established per ASTM:D-1557 for use in
evaluation of in-situ conditions and for future use during grading operations.
Direct shear tests were performed in accordance with ASTM:D-3080, on specimens at near
saturation under various normal loads. The results of tests are based on an 80% peak strength or
ultimate strength, whichever is lower, and are attached as Plates E and F.
Expansion tests were performed on typical specimens of natural soils in accordance with the
procedures outlined in ASTM:D-4829.
A consolidation test was performed on a representative sample based on ASTM:D-2435. The
consolidation plot is presented on Plate D.
PA2022-0295
COAST GEOTECHNICAL, INC.
Mr. and Mrs. Chase Sanderson
Geotechnical Engineering Investigation
18
TEST RESULTS
w. 0. 644322-01
October 18. 2022
Maximum Density/Optimum Moisture (ASTM: D-1557)
Boring Depth in Feet Maximum Density, pcf Optimum Moisture, %
1 0-5 112.0 10.0
Direct Shear (ASTM: D3080)
Boring Depth in Feet Cohesion Angle of Internal Friction
(lbs./sq. ft.) (Degrees)
1 0-5 (remolded) 100 31
2 3 50 31
Expansion Index (ASTM: D4829)
Boring Depth in Feet Expansion Index Expansion Potential
1 0-5 0 Very Low
Soluble Sulfate Analysis (ASTM: D516)
Boring Depth in Feet Soluble Sulfate (ppm)
1 0-5 68
PA2022-0295
COAST GEOTECHNICAL, INC.
SPECIFICATIONS FOR GRADING
SITE CLEARING
All existing vegetation shall be stripped and hauled from the site.
PREPARATION
After the foundation for the fill has been cleared, plowed or scarified, it shall be disced or bladed until
itis uniform and free from large clods, brought to a proper moisture content and compacted to not less
than ninety percent of the maximum dry density in accordance with ASTM:D-1557 (5 layers -25
blows per layer; 10 lb. hammer dropped 18"; 4" diameter mold).
MATERIALS
On-site materials may be used for fill, or fill materials shall consist of materials approved by the Soils
Engineer and may be obtained from the excavation of banks, borrow pits or any other approved
source. The materials used should be free of vegetable matter and other deleterious substances
and shall not contain rocks or lumps greater than six inches in maximum dimension.
PLAClNG, SPREADING AND COMPACTING FILL MATERIALS
The selected fill material shall be placed in layers which, when compacted, shall not exceed six
inches in thickness. Each layer shall be spread evenly and shall be thoroughly mixed during the
spreading to ensure uniformity of material and moisture of each layer.
Where moisture of the fill material is below the limits specified by the Soils Engineer, water shall be
added until the moisture content is as required to ensure thorough bonding and thorough compaction.
Where moisture content of the fill material is above the limits specified by the Soils Engineer, the fill
materials shall be aerated by blading or other satisfactory methods until the moisture content is as
specified.
After each layer has been placed, mixed and spread evenly, it shall be thoroughly compacted to not
less than 90 percent of the maximum dry density in accordance with ASTM:D-1557 (5 layers -25
blows per layer; 10 lbs. hammer dropped 18 inches; 4" diameter mold) or other density tests which
will attain equivalent results.
Compaction shall be by sheepfoot roller, multi-wheel pneumatic tire roller, track loader or other types
of acceptable rollers.
PA2022-0295
COAST GEOTECHNICAL, INC.
SPECIFICATIONS FOR GRADING PAGE2
Rollers shall be of such design that they will be able to compact the fill to the specified density.
Rolling shall be accomplished while the fill material is at the specified moisture content. Rolling of
each layer shall be continuous over the entire area and the roller shall make sufficient trips to ensure
that the desired density has been obtained. The final surface of the lot areas to receive slabs on grade
should be rolled to a dense, smooth surface.
The outside of all fill slopes shall be compacted by means of sheepfoot rollers or other suitable
equipment. Compaction operations shall be continued until the outer nine inches of the slope is at
least 90 percent compacted. Compacting of the slopes may be progressively in increments of three
feet to five feet of fill height as the fill is brought to grade, or after the fill is brought to its total height.
Field density tests shall be made by the Soils Engineer 9f the compaction of each layer of fill. Density
tests shall be made at intervals not to exceed two feet of fill height provided all layers are tested.
Where the sheepfoot rollers are used, the soil may be disturbed to a depth of several inches and
density readings shall be taken in the compacted material below the disturbed surface. When these
readings indicate that the density of any layer of fill or portion there is below the required 90 percent
density, the particular layer or portion shall be reworked until the required density has been obtained.
The grading specifications should be a part of the project specifications.
The Soil Engineer shall review the grading plans prior to grading.
INSPECTION
The Soil Engineer shall provide continuous supervision of the site clearing and grading operation so
that he can verify the grading was done in accordance with the accepted plans and specifications.
SEASONAL LIMITATIONS
No fill material shall be placed, spread or rolled during unfavorable weather conditions. When heavy
rains interrupt work, fill operations shall not be resumed until the field tests by the Soils Engineer
indicate the moisture content and density of the fill are as previously specified.
EXPANSIVE SOIL CONDITIONS
Whenever expansive soil conditions are encountered, the moisture content of the fill or recompacted
soil shall be as recommended in the expansive soil recommendations included herewith.
PA2022-0295
SITE VICINITY MAP
!!7
NEWPORT BEACH QUADRANGLE
CALIFORNIA -ORANGE CO.
7.5 MINUTE SERIES (TOPOGRAPHIC}
2€:
Geotechnical Engineering Investigation
6104 West Ocean Front
Newport Beach, California
UNITED STATES
DEPARTMENT OF THE INTERIOR
GEOLOGIC SURVEY
Work Order 644322
Plate No. 1
COAST GEOTECHNICAL, INC.
PA2022-0295
PLANS PREPARED BY:
OHA CONSTRUCTION
31234 W. NINE DRIVE
LAGUNA NIGUEL. CA 92677
PH: 951-990-4834
EMAIL: Oz.almendarez@gmall.com
SITE PLAN
West Ocean Front (Alley)
Boring#l
Geotechnical Engineering Investigation
824 Via Lido Nord
Newport Beach, California
Scale: 1" ::;;j 16'
Work Order 5455617-01
Plate No. 2
COAST GEOTECHNICAL, INC.
PA2022-0295
SEISMIC HAZARD ZONES MAP
26
~'
~'
26
'"'-~
~'
' .''-·,."--" ' ',, \
N]}WPORtC_')Bf--~ ' ·~;-~:t~
~',., <~f-')?~u\~~?.,:.
48
42
STATE OF CALIFORNIA
SEISMIC HAZARDS ZONES .
DeHneated In compliance with O.apter 7.8, Dlvirion 2 of the C!!llfomla Publlc Resources Code
/S_,,,,,k HuMds Mllpplng Ad}
. NEWPORT BEACH QUADRANGLE
OFFICIAL MAP
Liquefaction Zone Released: April 7, 1997
Landslide Zone Released: April 15, 1998
' , .. _/ '/'\ \ ~ "'°··-·-/ -), / ) ,_ ;:------::-----------·--/ f I ( -· '·" ·----.c----·-··-•1 a ----·-,~-----.
I I ( --~ ( MAP EXPLANATION
I I '2 o--...._ " _,// . \ ,...__
('\ I_I,,., ';1 I /! I Liquefaction ) · /! / / Areas where historic occurrence of liquefaction, or local geolOgical,
I · \ ~ geotechnical and groundwater conditions indicate a potential for
!/ ,/ //_JI \\ ~ permanent ground displacements such that mitigation as defined in, Public Resouroes Code Section 2693(0) would be required. '
/ / \ E,arthquake-lnduced Landslides
~/-( 2 58 \__~ -Areas where previous occurrence of landslide movement, or local
I" , topographic, geological, geotechnlcal and subsurface water conditions
/ \ indicate a potential for permanent ground displacements such that \._ C'",,..._ mitigation as de(ined In Public Resources Code Section 2693(c) would
/ .A '-._ '\. ,..__ be required.
Zones of Required Investigation:
Geotechnical Engineering Investigation
6104 West Ocean Front
Newport Beach, California
Work Order 644322
Plate No. 3
COAST GEOTECHN/CAL, INC.
PA2022-0295
TEMPORARY EXCAVATION ALONG PROPERTY LINES
BUILDING
FACE --
F.F.
NEW ~
FOOTING-----
(24")
/
4
//
/
SCALE: 1"~ 2'
WALL
ORP.L.
,,/
..
/I /
// l~EMPORARY ,f-----)' SLOPE /: /
// ! ~ BENCHING 7 ------~------V' ~
1: 1 PROJECTION
OVER-EXCAVATION
This plate is not a representation of actual site conditions. It is a
general representation of typical conditions and intended for the
illustration of geotechnical data only. The indicated scale is
approximate, and to be used for rough measurement only.
Geotechnical Engineering Investigation
6104 West Ocean Front
Newport Beach, California
Work Order 644322
Plate No. 4
COAST GEOTECHNICAL, INC.
PA2022-0295
POTENTIAL TSUNAMI RUNUP INUNDATION CAUSED BY A
SUBMARINE LANDSLIDE
'OJ' ~" ' ,,'fi:t
Ela1c:: Map: USGS To p::>13raph ic Map from Sure::! MAPS RASTER '
Source::: City of Ne:wp::, rt Elc::a: h, 2007 ba.e:d on un pu bli, hc::d '.·.·.·.
rc::,c::ao:: h b--/ J. C. Bo m::ro and othc::n at Uni""" ity of '
So ut he:: rn California "''
NOTES: ~.
This: m;ip S intt::ld.;:dlbr2,-.::r1,;:r.1.J b.nd UPi.:pl:1.nnif'&only. lnkam,.r.tianQnthriii M:lp Si oot "
s!ltictw:rt to !ii'ii:IV.;: .r. a.s;ubtititr.: ford-:t.;.ika:d 1-,'Qlog;ic iffiilli:5ti:£-tial15of individualdr;;.. · · .·· .. ·.· .• rDr d.:..s: it s:atisfy tho;:. 0":Lluatic.n r,;qu illil:mG:11:s;si;t 6:.rth in z-;ob:tic h:1.z:ud r,;:zub.t ions;.
Ga.rth Co l'!iiU tanbii lrtiil:rna.t ii::inal (EC(! Ma~ no r,;prz.:ntatio l?ii Or\.\'il.rlil.nttiidii ~El ing:
~'=1~0n0!~~:!!fo;a~~i~=d==i!r~~~rt~~~~~::i ,~~~
di.map with~ toanyda.im bya.ny is;:rorthirdp.t.tyon ilO:OUrtof.,oraris:ing
f<:,111. th,o uooolthi. rmpj
Project Num bc::r: 2706
Date: 2006
Geotechnical Engineering Investigation
6104 West Ocean Front
Newport Beach, California
Scale: 1 :60,000
0,_.s..,_.,._• ..... ....,•,.·•.._ .... ....,.,...,1.S Mile£
Area that would be inundated by a
tsunami generated by a submarire
landslide offshore of N9wport Beach
(areas at or lower than 3 2 foot elevation
N9wport Beach City Boundary
Sphere of Influence
Work Order 644322
Plate No. 5
COAST GEOTECHNICAL, INC.
PA2022-0295
UNIFIED SOIL CLASSIFICATION AND KEY TO BORING LOGS
UNITED SOIL CLASSIFICATION SYSTEM (ASTM D-2487)
PRIMARY DIVISIONS SYMBOLS SECONDARY DIVISIONS
GW WELL-GRADED GRAVELS, GRAVEL-SAND MIXTURES, LITTLE
GRAVEL AND CLEAN GRAVELS OR NO FINES
GRAVELLY (LITTLE OR NO
SOILS FINES) GP POORLY-GRADED GRAVELS, GRAVEL-SAND MIXTURES,
COARSE LITTLE OR NO FINES
GRAINED SOILS MORE THAN 50% GRAVELS WITH OF COARSE GM SIL TY GRAVELS, GRAVELS-SAND-SILT MIXTURES
FRACTION FINES
RETAINED ON (APPRECIABLE
NO.4SIEVE AMOUNT OF FINES) GC CLAYEY GRAVELS, GRAVELS-SAND-CLAY MIXTURES
SW WELL-GRADED SANDS, GRAVELLY SANDS, LITTLE OR NO
SAND AND CLEAN SAND FINES
SANDY SOILS (LITTLE OR NO
MORE THAN 50% FINES) SP POORLY-GRADED SANDS, GRAVELLY SANDS, LITTLE OR NO
OF MATERIAL IS FINES
LARGER THAN NO. MORE THAN 50%
200 SIEVE SIZE OF COARSE SAND WITH SM SILTY SANDS, SAND-SILT MIXTURES
FRACTION FINES
PASSING NO. 4 (APPRECIABLE
SIEVE AMOUNT OF FINES) SC CLAYEY SANDS, SAND-CLAY MIXTURES
INORGANIC SIL TS AND VERY FINE SANDS, ROCK FLOUR,
ML SILTY OR CLAYEY FINE SANDS OR CLAYEY SILTS WITH
SLIGHT PLASTICITY
FINE GRAINED SILTS AND LIQUID LIMIT INORGANIC CLAYS OF LOW TO MEDIUM PLASTICITY,
SOILS CLAYS LESS THAN 50 CL GRAVELLY CLAYS, SANDY CLAYS, SIL TY CLAYS, LEAN
CLAYS
OL ORGANIC SILTS AND ORGANIC SIL TY CLAYS OF LOW
PLASTICITY
MH INORGANIC SILTS, MICACEOUS OR DIATOMACEOUS FINE
MORE THAN 50% SAND OR SIL TY SOILS
OF MATERIAL IS SILTS AND LIQUID LIMIT
SMALLER THAN CLAYS GREATER THAN CH INORGANIC CLAYS OF HIGH PLASTICITY, FAT CLAYS
NO. 200 SIEVE 50
SIZE OH ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY,
ORGANIC SIL TS
HIGHLY ORGANIC SOILS PT ORGANIC SILTS AND ORGANIC SILTY CLAYS OF LOW
PLASTICITY
COARSE GRAINED SOILS FINE GRAINED SOILS
CONSISTENCY BLOWS/FT" CONSISTENCY BLOWS/FT"
VERY LOOSE 0-4 VERY SOFT 0-2
LOOSE 4-10 SOFT 2-4
MEDIUM DENSE 10 • 30 FIRM 4-8
DENSE 30-50 STIFF 8 -15
VERY DENSE OVER50 VERY STIFF 15 -30
HARD OVER30
* BLOWS/FT FOR A 140-POUND HAMMER FALLING 30 INCHES TO DRIVE A 2 INCH O.D., 1-3/8 INCH I.D. SPLIT
SPOON SAMPLER (STANDARD PENETRATION TEST)
KEY TO SAMPLE TYPE: U = UNDISTURBED SAMPLE B = BULK S = SPT SAMPLE
COAST GEOTECHN/CAL, INC.
PA2022-0295
COAST GEOTECHNICAL, INC.
(Text Supercedes)
PLATEA
EXP ANSI ON INDEX VERYLOW LOW MEDIUM HIGH VERY HIGH
0-20 21 -50 51 -90 91-130 130+
Footing Width
1 Story 12" 12" 12" 15" 15"
2 Story 15" 15" 15" 15" 15"
3 Story 18" 18" 18" 18" 18"
..
Exterior Footing Depth
1 Story 24" 24" 24" 24" 30"
2&3 Story 24" 24" 24" 24" 36"
•·
Interior Footing Depth
1 Story 24" 24" 24" 24" 30"
2&3 Story 24" 24" 24" 24" 36"
Footing Reinforcement 4 #5 Bars 4 #5 Bars 4 #5 Bars 4 #5 Bars 4 #5 Bars
2 Top 2 Top 2 Top 2 Top 2 Top
2 Bottom 2 Bottom 2 Bottom 2 Bottom 2 Bottom
Slab Thickness 5" Actual 5" Actual 5" Actual 5" Actual 5" Actual
Slab Reinforcement #4 Bars on #4 Bars on #4 Bars on #4 Bars on #4 Bars on
12" 12" 12" 12" 12"
Centers Both Centers Both Centers Both Centers Both Centers Both
Ways Ways Ways Ways Ways
Vapor Retarder (2) 15 mil 15 mil 15 mil 15 mil 15 mil
Membrane Membrane Membrane Membrane Membrane
.·
Garage Reinforcement #4 Bars on #4 Bars on #4 Bars on #4 Bars on #4 Bars on
12" 12" 12" 12" 12"
Centers Both Centers Both Centers Both Center Both Center Both
Ways Ways Ways Ways Ways
Grade Beam-Same as Adj. Same as Adj. Same as Adj. Same as Adj. Same as Adj.
Garage Entrance Ext. Ftg. Ext. Ftg. Ext.Ftg. Ext. Ftg. Ext. Ftg.
Capillary Break (3) 4" Clean 4" Clean 4" Clean 4" Clean 4" Clean
Aggregate Aggregate Aggregate Aggregate Aggregate
Presaturation Not Required Above Opt. 110% of Opt 130% of Opt 130% of Opt
To MIC to MIC to Depth MIC to Depth
Depth of Ftg. Depth Footing Footing
(No Testing) Footing
1. Basement slabs shall have a minimum thickness of six inches.
2. Floor slab shall be constructed over a 15 mil plastic membrane. The membrane shall be properly lapped, sealed and in
contact with the slab bottom.
3. Aggregate should be ½-inch or larger.
PA2022-0295
Date:
Q)
I-~ fu ~ z
9
10
21
21
39
9/27/2022 -en -Q) _: Q) c: en 5 s: a. Q) Q) 1ii ~ E (.) C: ~ u:: ·o Cl co en a. ~ ~ -B U
2 3.8
3 4.4
3 16.3
3 22.4
7 23.2
SUMMARY OF BORING NO. 1
-_:
LL -.c -a. Q)
Cl
5
10
15
Description
7" Concrete
FILL: SAND ---slightly silty, fine to medium-
grained, dry to damp
NATIVE: SAND ---clean, fine to medium-grained,
damp
SAND ---clean, fine to medium-grained, damp
SAND ---clean, fine to medium-grained, damp
SAND ---clean, medium to coarse-grained, moist
to very moist
SAND ---clean, fine to medium-grained, wet
SAND ---slightly silty, fine to coarse-grained, wet
End of boring at 12.5 feet
Groundwater at 7.0 feet
Sands are subject to caving
Elevation:
,_
0 0 (.)
Tan to Tan
Brown
Tan
Tan
Tan
Tan to Light
Gray Tan
Light Gray
Tan
Light Gray
Tan
E.G.
~ C: Q) -en "in C: 0 (.)
Loose to
Medium
Dense
Medium
Dense
Medium
Dense
Medium
Dense
Medium
Dense
Medium
Dense
Medium
Dense
Geotechnical Engineering Investigation
6104 West Ocean Front
Newport Beach, California
Work Order 644322
Plate B
COAST GEOTECHNICAL, INC.
PA2022-0295
Date: 9/27/2022
>-........ en ........ -~~ Q) ....: 'iii a. LL
55 t5' -1n c:' E .c Cl 0.. ·5 Cl ro -c:' -Cl) C.
~'#. Q) Cl Cl -U B
2
99.9 4.6
4
100.4 4.1
6
99 9.4
8
10
SUMMARY OF BORING NO. 2
Elevation:
...
0 Description 0 0
FILL: SAND ---slightly silty, fine to medium-Tan to Tan
grained, damp Brown
NATIVE: SAND ---clean, fine to coarse-grained, Yellow Tan
damp to Tan
SAND ---clean, fine to medium-grained, damp
SAND ---clean, fine to medium-grained, moist
End of boring at 8 feet
Groundwater at 8 feet
Sands are subject to caving
Tan
Tan
E.G.
>-(.)
C
Q) -en 'iii
C 0 0
Loose
Medium
Dense
Medium
Dense
Medium
Dense
Geotechnical Engineering Investigation
6104 West Ocean Front
Newport Beach, California
Work Order 644322
Plate C
COAST GEOTECHNICAL, INC.
PA2022-0295
CONSOLIDATION TEST RESULTS
[ Boring No. 2 @ 3 Feet l
Pressur~ (Kips Per Square Foot)
0.1 1 10
0.00 ~-----., J ~-
1.00 -----........... .......... -r,,,_
2.00 --......... --' -...... ' -,,
3.00 --C: G) u 4.00 ... G)
C. -C: 0 5.00 .:;
ffl "C
0 6.00 en C:
0 0
7.00
8.00
9.00
10.00
0 Test Specimen at In-Situ Moisture
• Test Specimen Submerged
Geotechnical Engineering Investigation Work Order 644322
6104 West Ocean Front
Newport Beach, California Plate No. D
COAST GEOTECHNICAL, INC.
PA2022-0295
SHEAR TEST RESULT
[ Boring No.1 @Oto 5 Feet {Remolded to 90%) )
5
4
-~ 3 I a.
32 -
0 1 2 3 4 5
Confining Pressure (kips/sq. ft.)
Remolded soil samples were tested at saturated conditions.
The sample had a dry density of 101.3 lbs./cu.ft. and a moisture content of 24.3 %.
Cohesion = 100 psf
Friction Angle= 31 degrees
Based on 80% peak strength or ultimate strength, whichever is lower
Geotechnical Engineering Investigation
6104 West Ocean Front
Newport Beach, California
Work Order 644322
Plate No. E
COAST GEOTECHNICAL, INC.
PA2022-0295
SHEAR TEST RESULT
( Boring No. 2 @ 3 feet )
5
4
-¢::
3 ci-Cl)
ul 0.
:.i2 -
0 1 2 3 4 5
Confining Pressure (kips/sq. ft.)
Native soil samples were tested at saturated conditions.
The sample had a dry density of 99.9 lbs./cu.ft. and a moisture content of 25.2 %.
Cohesion = 50 psf
Friction Angle = 31 degrees
Based on 80% peak strength or ultimate strength, whichever is lower
Geotechnical Engineering Investigation
6104 West Ocean Front
Newport Beach, California
Work Order 644322
Plate No. F
COAST GEOTECHNICAL, INC.
PA2022-0295
ALLOWABLE BEARING CAPACITY
Bearing Capacity Calculations are based on "Terzaghi's Bearing Capacity Theory"
Bearing Material: Compacted Fill
Properties:
Wet Density (y) = 110 pcf
Cohesion (C) = 100 psf
Angle of Friction (¢) = 31 degrees
Footing Depth (D) = 2 feet
Footing Width (B) = 1.3 feet
Factor of Safety = 3.0
Calculations -Ultimate Bearing Capacity
from Table 3.1 on page 127 of "Foundation Engineering Handbook", 1975
Ne = 32.67 Nq = 20.63 Nr = 25.99
Ou = 1.3 C Ne + y D Nq + 0.4 y B Ny (Square Footing)
= 1.3 * 100 * 32.67 + 110 * 2 * 20.63 + 0.4 * 110 * 1.25 * 25.99
= 4247 + 4538 + 1429 = 10214 psf
Allowable Bearing Capacity for Square Footing
3404 psf
Use 1800 psf
Ou = 1.0 C Ne + y D Nq + 0.5 y B Ny (Continuous Footing)
= 1.0 * 100 * 32.67 + 110 * 2 * 20.63 + 0.5 * 110 * 1.25 * 25.99
= 3267 + 4538 + 1786 = 9591 psf
Allowable Bearing Capacity for Continuous Footing
Oau= Ou/ F.S. =
Use 1800 psf
3197 psf
Increases: 750 psf / ft in depth over 2 feet
350 psf / ft in width over 1.25 feet
Geotechnical Engineering Investigation
6104 West Ocean Front
Newport Beach, California
Work Order 644322
Plate G
COAST GEOTECHNICAL, INC.
PA2022-0295
LATERAL EARTH PRESSURE CALCULATIONS
Retaining structures such as retaining walls, basement walls, and bulk-heads are commonly
used in foundation engineering, and they support almost vertical slopes of earth masses.
Proper design and construction of these structures require a through knowledge of the lateral
forces acting between the retaining structures and the soil masses being retained. These
lateral forces are due to lateral earth pressure.
Properties of earth material: Compacted fill
Wet Density (y)
Cohesion (C)
=
=
110 pcf
100 psf
Angle of Friction(</>) = 31 degrees
Coefficient of Friction = tan <I>
Therefore,
Coefficient of Friction = tan <I>
= tan <P = 0.601
Assumed H = 2 feet
Use 0.35
Pp= 0.5 y H2 tan2 ( 45° + <P 12) + 2 C H tan ( 45° + <P 12)
= 0.5*110*4*3.122+2*100*2*1.767
= 687 + 707 = 1394 lbs/ LF
1/2 EFP H2 = 1394
EFP = 697 psf / LF
EFP: passive pressure
Allowable Passive Pressure= 300 psf / LF ( with F.S. =2.32)
Geotechnical Engineering Investigation
6104 West Ocean Front
Newport Beach, California
Work Order 644322
Plate H
COAST GEOTECHNICAL, INC.
PA2022-0295
CALCULATION OF SUBGRADE REACTION
Subgrade reaction calculations are based on "Foundation Analysis and Design" Fourth
Edition, by Joseph E. Bowles.
Ks= 24 quit (for L\H = 1/2 inch)
Where:
Ks = subgrade reaction in k / ft3
quit = ultimate bearing capacity
For quit = 9.6 ksf (from bearing capacity calculations)
Ks = 24 * 9.59 k / ft3
= 230.2*1000/(12*12*12) lb/in3
= 133.2 lb/ in3
Use 100 pound per cubic inch
Geotechnical Engineering Investigation
6104 West Ocean Front
Newport Beach, California
COAST GEOTECHNICAL
Work Order 644322
Plate No. I
PA2022-0295
APPENDIX 8
Liquefaction Analysis by SPT
Geotechnical Engineering Investigation
6104 West Ocean Front
Newport Beach, California
COAST GEOTECHNICAL, INC.
PA2022-0295
LIQUEFACTION ANALYSIS BY SPT
FOR BORING NO. 1
C = ( P / a ' )112 < 2 P = 2089 psf N a O , a
(N1)50 = Nm CN CE Cs CR Cs
CSR= 1'av / a0' = 0.65 ( a0 I a0') rd ( amax / g )
llllli~llll lllllill~illlll llllilllillll llil~l■l~l llll~fill1111111111111~~111:1111111111111111~1~111~1111!1~11111 ~~I i~li'ii ~~~~~ i~ii l~li!l llliilllllll~i~llllllllliil,
3 315.0 315.0 9 2.00 I 1.00 I 1.05 I 0.75 I 1.20 17.0 0.99 I 0.47 2 0.19 I 1.10 I 0.21
5 525.0 525.0 10 1.99 I 1.00 I 1.05 I 0.75 I 1.20 18.9 0.99 I 0.47 3 0.21 I 1.10 I 0.23
7 745.0 620.2 21 1.84 I 1.00 I 1.05 I 0.75 I 1.20 36.4 0.99 I 0.57 3 0.60 I 1.10 I 0.66
9 965.0 I 715.4 21 1.71 I 1.00 I 1.05 I 0.75 I 1.20 33.9 0.98 I 0.63 3 0.60 I 1.10 I 0.66
11 1185.0 I 810.6 39 1.61 I 1.00 I 1.05 I 0.75 I 1.20 59.2 0.98 I o.68 7 0.60 I 1.10 I 0.66
Note: 1. Moist unit weight of 105 pcf, saturated unit weight of 11 0 pcf, and groundwater at 5 feet
2. Magnitude of 7.2 and peak ground acceleration of 0.731 g
3. According to Figure 7.1, soil layers having (N1)60 higher than 30 are not considered liquefiable.
Geotechnical Engineering Investigation
6104 West Ocean Front
Newport Beach, California
COAST GEOTECHNICAL, INC.
Work Order 644322
Plate M
0.44
0.49
1.17
1.05
0.97
PA2022-0295
Opon-Filo Report 97---00
PA2022-0295
0
5
E
.c. a
(I.) 10
0
15
20
Stress Reduction Coefficient, rd
0.2 0.4 0.6 0.8
Average valu~s
by Seed &
Idriss (1971)
Approximate average
values from Eq. 2
Range for different
soil profiles by
Seed & Idriss (1971)
1.0
FIG. 1. rd versus Depth Curves Developed by Seed and Idriss
(1971) with Added Mean-Value Lines Plotted from Eq. (2)
PA2022-0295
TABLE 2. Corrections to SPT (Modified from Skempton 1986)
as Listed by Robertson and Wride (1998)
· Factor Equipment variable Term Correction
(1) (2) (3) (4)
Overburden pressure -CN (P0 /cr 'vo)9·5
Overburden pressure -CN CN < 1.7
Energy ratio Donut hammer CE 0.5-1.0
Energy ratio Safety hammer CE 0.7-1.2
Energy ratio Automatic-trip Donut-CE 0.8-1.3
type hammer
Borehole diameter 65-115 mm CB 1.0
Borehole diameter 150 mm CB 1.05
Borehole diameter 200 mm Ca 1.15
Rod length <3 m CR 0.75
Rod length 3-4 m CR 0.8
Rod length 4-6 m CR 0.85
Rod length 6-10 m CR 0.95
Rod length 10-30 m CR 1.0
Sampling method Standard sampler Cs 1.0
Sampling method Sampler without liners Cs 1.1-1.3
PA2022-0295
0.6 ________ __,El",,_3_7....,...------,..-------------.
Percent Fines = 35 15 ~5
I I I fi? 0.5 f-----+-----+i--+-I
I l I
0::: £
0 ~ a::
~ C .!!l <II "<ii Ci) a::
.9 0 >,
(.)
'--0 oc
(/)
£
.Q
(U a:
(I)
(/) i CJ)
• Q 13 >-(.)
I I I I ,
I r I I ,
r
I
I I
I
I I
I
I
I
I
' I A10
,,__
, SPT Clean Sand Base Curve
I
I 0.3 _____ 20--tl ________ , ____________ _
.,2 /
I I I J-7 • ••o ,~ 60
0.21----.so-"....._--f:;;~~--:r--b;liµM...----t-----t-------i
10
30 &'l.:J • 22 •
1s• FINES CONTENT~ 5%
lil;Jo
-. 1 Adjustment
Recommended
By Workshop
10
Modified Chinese Code Proposal (clay content"' 5%)®
Pan -America data
Japanese data
Chinese data
20
Marginal No
Liquefaclion Liquefaction Liquefaction
• m
30 40
0
A.
Corrected Blow Count, (N1)60
50
FIG. 2. SPT Clean-Sand Base Curve for Magnitude 7.5 Earth-
quakes with Data from Liquefaction Case Histories (Modified
from Seed et al. 1985)
PA2022-0295
~ Cl'l ~
s.!' 0 ....
0 ~ £I..
00 = ·--~
0
Cf)
0 -0 ::, .... -~ d 00 ca :E
4.5
4
3.5
3
2.5
2
1.5
I
0.5
0
-+-Seed and Idriss~ ( 1982) -+-----.----=-1--------,-1 R nge of recommen ed -a-Idriss
----------,o....+--S ....... F_f_ro ___ m=--N---C;...,_EE_,;_;;,,;;;._ x Ambraseys (1985}
5.0 6.0
Workshop ◊ Arango (1996)
7.0
♦ Arango (1996)
-+-Andrus and Stokoe
.A. Youd and Noble, PL<20%
.6. Youd and Noble, PL<32%
.t. Youd and Noble, PL<50%
8.0 9.0
Earthquake Magnitude, Mw
FIG. 12. Magnitude Scaling Factors Derived by Various Inves-
tigators (Reproduced from Youd .and Noble 1997a)
PA2022-0295
10·2,.---,----,--r-r-,----r-r-rr---r----r~r--,.--,.--,,--r--r,,------,,-..---.
10 3 .
--"' >-..
C ·-0
'-
(/')
'-0
~ .c
(/')
-4
10
-~ 10 ..__ __ ._____._ __ ._......,_._..__,__ __ ._____.__..__"--,1..-J....~L---J..-__,j
,o-5 ,o-4
'Yeff {Getf/Gmax)
FIG. ·:z. -PLOT FOR DETERMINATION OF INDUCED STRAIN
IN SAND DEPOSITS
PA2022-0295
Cyclic Shear Strain, r., -percent ~ 2 xy 10-.J ,o-10 •1
10·3 .--,--,--,-.,----.---,-i--,--,.---,----r---,---.---_;
C ·2
~10 ...
CJ
0.
I
CJ w
C:
0
u
0
0.
E 10 1
0 u
0 -
fJ
::I
0
C: ·-0
'--
u ·-.. -
:::: 10
:::: 5 ' '
' ' ' ' '
' ' ' '
'
'
' '
' ' '
' ' ' ' ' ' ' '
' ' ' ' ' ' '
' ' ' ' '
' ' ' ' ' '
' '
' '\
15 Cycles
' ' ' '
' ' ' '
'
'
'
'\
' '
' '
'
....
' '
.... .... ....
FIG. 3 -RELATIONSHIP BETWEEN VOLUMETRIC STRAIN, SHEAR STRAIN,
AND PENETRATION RESISTANCE FOR DRY SANDS
PA2022-0295
TABLE 1 -INFLUENCE OF EARTHQUAKE MAGNITUDE ON VOLUMETRIC
STRAIN RATIO FOR DRY SANDS
Earthquake
magnitude
(1)
8-1/2
7-1/2
6-3/4
6
5-1/4
Number of representative
cycles at 0.65 ,. max
(2)
26
15
10
5
2-3
Volumetric strain ratio,
Ec,N /ec.tv-1s
(3)
1.25
1.0
0.85
0.6
0.4
PA2022-0295
Influence of Fines Content
In the original development, Seed et al. (1985) noted an
apparent. increase of CRR with increased fines content.
Whether this increase is caus~d by an increase of liquefaction
resistance or a decrease of penetration resistance is not clear.
Based on the empirical data available, Seed et al. developed
CRR curves for various fines contents reproduced in Fig. 2. A
revised correction for fines content was developed by work-
shop attendees to better fit the empirical database and to better
support computations with spreadsheets and other electronic
computational aids.
The workshop participants recommend ( 5) and ( 6) as ap-
proximate corrections for the influence of fines content (FC)
on CRR. Other grain characteristics, such as soil plasticity,
may affect liquefaction resistance as well as fines content, but
widely accepted corrections for these factors have not been
developed. Hence corrections based solely on fines content
should be used with engineering judgment and caution. The
following equations were developed by I. M. Idriss with the
assistance of R. B. Seed for correction of (N1)60 to an equiv-
alent clean sand value, (N1)6ocs:
(5)
where a and J3 = coefficients determineq from the following
relationships: ·
a = 0 for FC s 5% (6a)
a = exp[l.76 -(190/FC2)] for 5% < PC < 35% (6b)
a = 5.0 . for FC ~ 35% (6c)
j3 = 1.0 for FC < 5% (7a)
f3 = [0.99 + (FC1.5/l,000)] for 5% < FC < 35% (7b)
f3 = 1.2 for FC > 35% (7c)
These equations may be used for routine liquefaction resis-
tance calculations. A back-calculated curve for a fines content
of 35% is essentially congruent with the 35% curve plotted in
Fig. 2. The back-calculated curve for a fines contents of 15%
plots to the right of the original 15% curve.
PA2022-0295
Recommended Procedures for Implementation of DMG Special Publication 117 Guidelines for Analyzing and
Mitigating Liquefaction Hazards in California
0.6r-----,-----,-----,-------.-------.
Volumetric Strain-%
0.5 10 5 4 3 2 0.5 I
I
0.4
IoY...
a;.' 0
0.3
0.2
0.1
I
I
I
I
I
)
/,0.2
I I
I I
I I
; // p.1 I I / / I I I
I I · I / I I
I I I
/ I I '/ I I
I I / I
I I
I I I I I / I / / I
I I I I / /
/ / ,.,,"'
// / /
//
//
I/
'//
'//
'//
1//
1/
O"'--------':------'----___JL------__L_---_J 0 10 20 30 40 50
Figure 7.11. Relationship Between Cyclic Stress Ratio, (N,\0 and Volumetric Strain
for Saturated Clean Sands and Magnitude = 7 .5 (After Tokimatsu and Seed, 1987)
60
PA2022-0295
APPENDIXC
Calculations of Seismically Induced Settlement
Geotechnical Engineering Investigation
6104 West Ocean Front
Newport Beach, California
COAST GEOTECHN/CAL, INC.
PA2022-0295
LIQUEFACTION ANALYSIS
Hole No.=1 Water Depth=5 ft
Shear Stress Ratio
(ft) O 0 ,------.-~~~-~----.-~~--.--,------,--------,
2
4
6
-8
10
< g:i 12
fs1=1
CRR -CSR fs1--
Shaded Zone has Liquefaction Potential
CivilTech Corporation
Sanderson
Factor of Safety Settlement
0 1 5 0 (in.)
I I I I I I I I -~~~~
S = 0.71 in.
Saturated
Unsaturat. -
Magnitude=7.2
Acceleration=. 731 g
Soil Description
Plate A-1
PA2022-0295
************************************************************************************
*******************
LIQUEFACTION ANALYSIS SUMMARY
Copyright by CivilTech Software
www.civiltech.com
************************************************************************************
*******************
Font: Courier New, Regular, Size 8 is recommended for this report.
Licensed to, 10/5/2022 8:36:14 AM
Input File Name: G:\LiquefyS\Sanderson, 6104 W. Oceanfront NB.liq
Title: Sanderson
Subtitle:
Surface Elev.=
Hole No.=1
Depth of Hole= 12.50 ft
Water Table during Earthquake= 5.00 ft
Water Table during In-Situ Testing= 5.00 ft
Max. Acceleration= 0.73 g
Earthquake Magnitude= 7.20
Input Data:
Surface Elev.=
Hole No.=1
Depth of Hole=12.50 ft
Water Table during Earthquake= 5.00 ft
Water Table during In-Situ Testing= 5.00 ft
Max. Acceleration=0.73 g
Earthquake Magnitude=7.20
No-Liquefiable Soils: CL, OL are Non-Liq. Soil
1. SPT or BPT Calculation.
2. Settlement Analysis Method: Ishihara/ Yoshimine
3. Fines Correction for Liquefaction: Idriss/Seed
4. Fine Correction for Settlement: During Liquefaction*
5. Settlement Calculation in: All zones*
6. Hammer Energy Ratio,
7. Borehole Diameter,
8. Sampling Method,
9. User request factor of safety (apply to CSR),
Plot one CSR curve (fsl=l)
10. Use Curve Smoothing: Yes*
* Recommended Options
In-Situ Test Data:
Depth SPT gamma Fines
Ce= 1
User= 1
Cb= 1.05
Cs= 1. 2
PA2022-0295
ft pcf %
0.00 9.00 105.00 2.00
3.00 9.00 105.00 2.00
5.00 10.00 125.00 3.00
7.00 21.00 125.00 3.00
9.00 21.00 125.00 3.00
11.00 39.00 125.00 7.00
Output Results:
Settlement of Saturated Sands=0.37 in.
Settlement of Unsaturated Sands=0.34 in.
Total Settlement of Saturated and Unsaturated Sands=0.71 in.
Differential Settlement=0.353 to 0.466 in.
Depth CRRm CSRfs F.S. S_sat. S_dry S_all
ft in. in. in.
0.00 0.17 0.48 5.00 0.37 0.34 0.71
0.05 0.17 0.48 5,00 0.37 0.34 0.71
0.10 0.17 0.48 5.00 0.37 0. 34 0.71
0.15 0,17 0.47 5.00 0.37 0.34 0.71
0.20 0.17 0.47 5.00 0.37 0. 34 0.71
0,25 0.17 0.47 5.00 0.37 0.34 0.71
0.30 0.17 0.47 5.00 0.37 0. 34 0,71
0.35 0.17 0.47 5.00 0.37 0.34 0.70
0.40 0.17 0.47 5.00 0.37 0.34 0.70
0.45 0.17 0.47 5.00 0.37 0.34 0.70
0.50 0.17 0.47 5.00 . 0. 37 0;34 0.70
0.55 0.17 0.47 5.00 0.37 0.34 0.70
0.60 0.17 0.47 5.00 0.37 0. 34 0.70
0.65 0.17 0.47 5 .00, 0.37 0.34 0.70
0.70 0.17 0.47 5.00 0.37 0. 34 0.70
0.75 0.17 0.47 5.00 0.37 0.34 0.70
0.80 0.17 0.47 5.00 0.37 0.34 0.70
0.85 0.17 0.47 5.00 0.37 0.34 0.70
0.90 0.,17 0.47 5.00 0.37 0.33 0.70
0.95 0.17 0.47 5.00 0.37 0.33 0.70
1.00 0.17 0.47 5.00 0.37 0.33 0.70
1.05 0.17 0.47 5.00 0.37 0.33 0.70
1.10 0.17 0.47 5.00 0.37 0.33 0.70
1.15 0.17 0.47 5.00 0.37 0.33 0.70
1.20 0.17 0.47 5.00 0.37 0.33 0.70
1.25 0.17 0.47 5.00 0.37 0.33 0.70
1.30 0.17 0.47 5.00 0.37 0.33 0.70
1.35 0.17 0.47 5.00 0.37 0.33 0.70
1.40 0.17 0.47 5.00 0.37 0.33 0.70
1.45 0.17 0.47 5.00 0.37 0.33 0.70
1.50 0.17 0.47 5.00 0.37 0.33 0.70
PA2022-0295
1.55 0.17 0.47 5.00 0.37 0.33 0.70
1.60 0.17 0.47 5.00 0.37 0.33 0.70
1.65 0.17 0.47 5.00 0.37 0.33 0.69
1. 70 0.17 0.47 5.00 0.37 0.33 0.69
1. 75 0.17 0.47 5.00 0.37 0.33 0.69
1.80 0.17 0.47 5.00 0.37 0.33 0.69
1.85 0.17 0.47 5.00 0.37 0.33 0.69
1.90 0.17 0.47 5.00 0.37 0.33 0.69
1.95 0.17 0.47 5.00 0.37 0.32 0.69
2.00 0.17 0.47 5.00 0.37 0.32 0.69
2.05 0.17 0.47 5.00 0.37 0.32 0.69
2.10 0.17 0.47 5.00 0.37 0.32 0.69
2.15 0.17 0.47 5.00 0.37 0.32 0.69
2.20 0.17 0.47 5.00 0.37 0.32 0.69
2.25 0.17 0.47 5.00 0.37 0.32 0.69
2.30 0.17 0.47 5.00 0.37 0.32 0.69
2.35 0.17 0.47 5.00 0.37 0.32 0.69
2.40 0.17 0.47 5.00 0.37 0.32 0.68
2.45 0.17 0.47 5.00 0.37 0.32 0.68
2.50 0.17 0.47 5.00 0.37 0.32 0.68
2.55 0.17 0.47 5.00 0.37 0.32 0.68
2.60 0.17 0.47 5.00 0.37 0.31 0.68
2.65 0.17 0.47 5.00 0.37 0.31 0.68
2.70 0.17 0.47 5.00 0.37 0.31 0.68
2.75 0.17 0.47 5.00 0.37 0.31 0.68
2.80 0.17 0.47 5.00 0.37 0.31 0.68
2.85 0.17 0.47 5.00 0.37 0.31 0.68
2.90 0.17 0.47 5.00 0.37 0.31 0.67
2.95 0.17 0.47 5.00 0.37 0.31 0.67
3.00 0.17 0.47 5.00 0.37 0.30 0.67
3.05 0.17 0.47 5.00 0.37 0.30 0.67
3.10 0.17 0.47 5.00 0.37 0.30 0.67
3.15 0.18 0.47 5.00 · 0.37· 0.30 0.66
3.20 0.18 0.47 5.00 0.37 0.29 0.66
3.25 0.18 0.47 5.00 0.37 0.29 0.66
3.30 0.18 0.47 5.00 0.37 0.29 0.66
3.35 0.18 0.47 5.00 0.37 0.29 0.65
3.40 0.18 0.47 5.00 0.37 0.28 0.65
3.45 0.18 0.47 5.00 0.37 0.28 0.64
3.50 0.18 0.47 5.00 0.37 0.27 0.64
3.55 0.18 0.47 5.00 0.37 0.27 0.64
3.60 0.18 0.47 5.00 0.37 0.26 0.63
3.65 0.18 0.47 5.00 0.37 0.26 0.62
3.70 0.18 0.47 5.00 0.37 0.25 0.62
3.75 0.18 0.47 5.00 0.37 0.24 0.61
3.80 0.18 0.47 5.00 0.37 0.24 0.60
3.85 0.18 0.47 5.00 0.37 0.23 0.59
3.90 0.18 0.47 5.00 0.37 0.22 0.58
3.95 0.18 0.47 5.00 0.37 0.20 0.57
4.00 0.18 0.47 5.00 0.37 0.19 0.56
PA2022-0295
4.05 0.18 0.47 5.00 0.37 0.17 0.54
4.10 0.18 0.47 5.00 0.37 0.16 0.52
4.15 0.18 0.47 5.00 0.37 0.14 0.51
4.20 0.19 0.47 5.00 0.37 0.12 0.49
4.25 0.19 0.47 5.00 0.37 0.11 0.48
4.30 0.19 0.47 5.00 0.37 0.09 0.46
4.35 0.19 0.47 5.00 0.37 0.08 0.44
4.40 0.19 0.47 5.00 0.37 0.06 0.43
4.45 0.19 0.47 5.00 0.37 0.04 0.41
4.50 0.19 0.47 5.00 0.37 0.03 0.39
4.55 0.19 0.47 5.00 0.37 0.01 0.38
4.60 0.19 0.47 5.00 0.37 0.01 0.38
4.65 0.19 0.47 5.00 0.37 0.01 0.38
4.70 0.19 0.47 5.00 0.37 0.01 0.38
4.75 0.19 0.47 5.00 0.37 0.01 0.37
4.80 0.19 0.47 5.00 0.37 0.01 0.37
4.85 0.19 0.47 5.00 0.37 0.00 0.37
4.90 0.19 0.47 5.00 0.37 0.00 0.37
4.95 0.19 0.47 5.00 0.37 0.00 0.37
5.00 0.19 0.47 0.41* 0.37 0.00 0.37
5.05 0.20 0.47 0.42* 0.35 0.00 0.35
5.10 0.20 0.47 0.43* 0.34 0.00 0.34
5.15 0.21 0.48 0.44* 0.32 0.00 0.32
5.20 0.21 0.48 0.44* 0.31 0.00 0.31
5.25 0.22 0.48 0.45* 0.29 0.00 0.29
5.30 0.22 0.48 0.46* 0.28 0.00 0.28
5.35 0.23 0.49 0.47* 0.26 0.00 0.26
5.40 0.23 0.49 0.48* 0.25 0.00 0.25
5.45 0.24 0.49 0.49* 0.24 0.00 0.24
5.50 0.25 0.49 0.50* 0.22 0.00 0.22
5.55 0.25 0.50 0.51* 0.21 0.00 0.21
5.60 0.26 0.50 0.52* 0.20 0.00 0.20
5.65 0.26 0.50 0.53* 0.19· 0.00 0.19
5.70 0.27 0.50 0.54* 0.17 0.00 . 0.17
5.75 0.28 0.51 0.55* 0.16 0.00 0.16
5.80 0.28 0.51 0.56* 0.15 0.00 0.15
5.85 0.29 0.51 0.57* 0.14 0.00 0.14
5.90 0.30 0.51 0.58* 0.13 0.00 0.13
5.95 0.30 0.51 0.59* 0.12 0.00 0.12
6.00 0.31 0.52 0.60* 0.11 0.00 0.11
6.05 0.32 0.52 0.62* 0.10 0.00 0.10
6.10 0.33 0.52 0.63* 0.09 0.00 0.09
6.15 0.34 0.52 0.65* 0.08 0.00 0.08
6.20 0.35 0.52 0.66* 0.07 0.00 0.07
6.25 0.36 0.53 0.68* 0.06 0.00 0.06
6.30 0.37 0.53 0.70* 0.05 0.00 0.05
6.35 0.38 0.53 0.72* 0.05 0.00 0.05
6.40 0.39 0.53 0.74* 0.04 0.00 0.04
6.45 0.41 0.53 0.77* 0.03 0.00 0.03
6.50 0.43 0.54 0.81* 0.03 0.00 0.03
PA2022-0295
6.55 0.47 0.54 0.87* 0.02 0.00 0.02
6.60 0.55 0.54 1.03 0.02 0.00 0.02
6.65 0.55 0.54 1.02 0.02 0.00 0.02
6.70 0.55 0.54 1.02 0.01 0.00 0.01
6.75 0.55 0.55 1.02 0.01 0.00 0.01
6.80 0.55 0.55 1.01 0.01 0.00 0.01
6.85 0.55 0.55 1.01 0.01 0.00 0.01
6.90 0.55 0.55 1.01 0.01 0.00 0.01
6.95 0.55 0.55 1.00 0.01 0.00 0.01
7.00 0.55 0.55 1.00 0.01 0.00 0.01
7.05 0.55 0.56 1.00* 0.01 0.00 0.01
7.10 0.55 0.56 0.99* 0.01 0.00 0.01
7.15 0.55 0.56 0.99* 0.01 0.00 0.01
7.20 0.55 0.56 0.99* 0.01 0.00 0.01
7.25 0.55 0.56 0.99* 0.01 0.00 0.01
7.30 0.55 0.56 0.98* 0.01 0.00 0.01
7.35 0.55 0.57 0.98* 0.01 0.00 0.01
7.40 0.55 0.57 0.98* 0.01 0.00 0.01
7.45 0.55 0.57 0.97* 0.00 0.00 0.00
7.50 0.55 0.57 0.97* 0.00 0.00 0.00
7.55 0.55 0.57 0.97* 0.00 0.00 0.00
7.60 0.55 0.57 0.97* 0.00 0.00 0.00
7.65 0.55 0.58 0.96* 0.00 0.00 0.00
7.70 0.55 0.58 0.96* 0.00 0.00 0.00
7.75 0.55 0.58 0.96* 0.00 0.00 0.00
7.80 0.55 0. 58 0.96* 0.00 0.00 0.00
7.85 0.55 0.58 0.95* 0.00 0.00 0.00
7.90 0.55 0.58 0.95* 0.00 0.00 0.00
7.95 0.55 0.58 0.95* 0.00 0.00 0.00
8.00 0.55 0.59 0.95* 0.00 0.00 0.00
8.05 0.55 0.59 0.95* 0.00 0.00 0.00
8.10 0.55 0.59 0.94* 0.00 0.00 0.00
8.15 0.55 0.59 0.94* 0.00 0.00 0.00
8.20 0.55 0.59 0.94* 0.00 0.00 0.00
8.25 0.55 0.59 0.94* 0.00 0.00 0.00
8.30 0.55 0.59 0.93* 0.00 0.00 0.00
8.35 0.55 0.60 0.93* 0.00 0.00 0.00
8.40 0.55 0.60 0.93* 0.00 0.00 0.00
8.45 0.55 0.60 0.93* 0.00 0.00 0.00
8.50 0.55 0.60 0.93* 0.00 0.00 0.00
8.55 0.55 0.60 0.92* 0.00 0.00 0.00
8.60 0.55 0.60 0.92* 0.00 0.00 0.00
8.65 0.55 0.60 0.92* 0.00 0.00 0.00
8.70 0.55 0.60 0.92* 0.00 0.00 0.00
8.75 0.55 0.61 0.92* 0.00 0.00 0.00
8.80 0.55 0.61 0.91* 0.00 0.00 0.00
8.85 0.55 0.61 0.91* 0.00 0.00 0.00
8.90 0.55 0.61 0.91* 0.00 0.00 0.00
8.95 0.55 0.61 0.91* 0.00 0.00 0.00
9.00 0.55 0.61 0.91* 0.00 0.00 0.00
PA2022-0295
9.05 0.55 0.61 0.91* 0.00 0.00 0.00
9.10 0.55 0.61 0.90* 0.00 0.00 0.00
9.15 0.55 0.61 0.90* 0.00 0.00 0.00
9.20 0.55 0.62 0.90* 0.00 0.00 0.00
9.25 0.55 0.62 0.90* 0.00 0.00 0.00
9.30 0.55 0.62 0.90* 0.00 0.00 0.00
9.35 0.55 0.62 0.90* 0.00 0.00 0.00
9.40 0.55 0.62 0.89* 0.00 0.00 0.00
9.45 0.55 0.62 0.89* 0.00 0.00 0.00
9.50 0.55 0.62 0.89* 0.00 0.00 0.00
9.55 0.55 0.62 0.89* 0.00 0.00 0.00
9.60 0.55 0.62 0.89* 0.00 0.00 0.00
9.65 0.55 0.63 0.89* 0.00 0.00 0.00
9.70 0.55 0.63 0.89* 0.00 0.00 0.00
9.75 0.55 0.63 0.88* 0.00 0.00 0.00
9.80 0.55 0.63 0.88* 0.00 0.00 0.00
9.85 0.55 0.63 0.88* 0.00 0.00 0.00
9.90 0.55 0.63 0.88* 0.00 0.00 0.00
9.95 0.55 0.63 0.88* 0.00 0.00 0.00
10.00 0.55 0.63 0.88* 0.00 0.00. 0.00
10.05 0.55 0.63 0.88* 0.00 0.00 0.00
10.10 0.55 0.63 0.87* 0.00 0.00 0.00
10.15 0.55 0.64 0.87* 0.00 0.00 0.00
10.20 0.55 0.64 0.87* 0.00 0.00 0.00
10.25 0.55 0.64 0.87* 0.00 0.00 0.00
10.30 0.55 0.64 0.87* 0.00 0.00 0.00
10.35 0.55 0.64 0.87* 0.00 0.00 0.00
10.40 0.55 0.64 0.87* 0.00 0.00 0.00
10.45 0.55 0.64 0.86* 0.00 0.00 0.00
10.50 0.55 0.64 0.86* 0.00 0.00 0.00
10.55 0.55 0.64 0.86* 0.00 0.00 0.00
10.60 0.55 0.64 0.86* 0.00 0.00 0.00
10.65 0.55 0.65 0.86* 0.00. 0.00 0.00
10.70 0.55 0.65 0.86* 0.00 0.00 0.00
10.75 0.55 0.65 0.86* 0.00 0.00 0.00
10.80 0.55 0.65 0.86* 0.00 0.00 0.00
10.85 0.55 0.65 0.86* 0.00 0.00 0.00
10.90 0.55 0.65 0.85* 0.00 0.00 0.00
10.95 0.55 0.65 0.85* 0.00 0.00 0.00
11.00 0.55 0.65 0.85* 0.00 0.00 0.00
11.05 0.55 0.65 0.85* 0.00 0.00 0.00
11.10 0.55 0.65 0.85* 0.00 0.00 0.00
11.15 0.55 0.65 0.85* 0.00 0.00 0.00
11.20 0.55 0.65 0.85* 0.00 0.00 0.00
11.25 0.55 0.66 0.85* 0.00 0.00 0.00
11.30 0.55 0.66 0.85* 0.00 0.00 0.00
11.35 0.55 0.66 0.84* 0.00 0.00 0.00
11.40 0.55 0.66 0.84* 0.00 0.00 0.00
11.45 0.55 0.66 0.84* 0.00 0.00 0.00
11.50 0.55 0.66 0.84* 0.00 0.00 0.00
PA2022-0295
11.55 0.55 0.66 0.84* 0.00 0.00 0.00
11.60 0.55 0.66 0.84* 0.00 0.00 0.00
11.65 0.55 0.66 0.84* 0.00 0.00 0.00
11.70 0.55 0.66 0.84* 0.00 0.00 0.00
11.75 0.55 0.66 0.84* 0.00 0.00 0.00
11.80 0.55 0.66 0.84* 0.00 0.00 0.00
11.85 0.55 0.66 0.83* 0.00 0.00 0.00
11.90 0.55 0.67 0.83* 0.00 0.00 0.00
11.95 0.55 0.67 0.83* 0.00 0.00 0.00
12.00 0.55 0.67 0.83* 0.00 0.00 0.00
12.05 0.55 0.67 0.83* 0.00 0.00 0.00
12.10 0.55 0.67 0.83* 0.00 0.00 0.00
12.15 0.55 0.67 0.83* 0.00 0.00 0.00
12.20 0.55 0.67 0.83* 0.00 0.00 0.00
12.25 0.55 0.67 0.83* 0.00 0.00 0.00
12.30 0.55 0.67 0.83* 0.00 0.00 0.00
12.35 0.55 0.67 0.83* 0.00 0.00 0.00
12.40 0.55 0.67 0.82* 0.00 0.00 0.00
12.45 0.55 0.67 0.82* 0.00 0.00 0.00
12.50 0.55 0.67 0.82* 0.00 0.00 0.00
* F.S.<1, Liquefaction Potential Zone
(F.S. is limited to 5, CRR is limited to 2, CSR is limited to 2)
Units: Unit: qc, fs, Stress or Pressure= atm (1.0581tsf); Unit Weight =
pcf; Depth= ft; Settlement= in.
1 atm (atmosphere)= 1 tsf (ton/ft2)
CRRm Cyclic resistance ratio from soils
CSRsf Cyclic stress ratio induced by a given earthquake (with user
request factor of safety)
F.S. Factor of Safety against liquefaction, F.S.=CRRm/CSRsf
S sat Settlement from saturated sands
S_dry Settlement from Unsaturated Sands
S_all Total Settlement from Saturated and Unsaturated Sands
NoLiq No-Liquefy Soils
PA2022-0295
6104 W Oceanfront, Newport Beach, CA 92663, USA
Latitude, Longitude: 33.625522, -117.9491785
Design Code Reference Document ASCE7-16
II
; Site Class D -Default (See Section 11.4.3)
Type
Ss
S1
SMs
SM1
Sos
: So1
:Type
; SDC
j Fa
Fv
PGA
FPGA
PGAM
[ TL
SsRT
SsUH
SsD
S1RT
· S1UH
S1D
PGAd
PGAuH
, CRs
CR1
Cv
Value
1.394
0.499
1.672
null -See Section 11.4.8
1.115
null -See Section 11.4.8
Value
null -See Section 11.4.8
1.2
null -See Section 11.4.8
0.609
1.2
0.731
8
1.394
1.539
2.596
0.499
0.543
0.827
1.051
0.609
0.905
0.918
1.379
Description
Description
MCER ground motion. (for 0.2 second period)
MCER ground motion. (for 1.0s period)
Site-modified spectral acceleration value
Site-modified spectral acceleration value
Numeric seismic design value at 0.2 second SA
Numeric seismic design value at 1.0 second SA
Seismic design category
Site amplification factor at 0.2 second
Site amplification factor at 1.0 second
MCEG peak ground acceleration
Site amplification factor at PGA
Site modified peak ground acceleration
Long-period transition period in seconds
Probabilistic risk-targeted ground motion. (0.2 second)
Factored uniform-hazard (2% probability of exceedance in 50 years) spectral acceleration
Factored deterministic acceleration value. (0.2 second)
Probabilistic risk-targeted ground motion. (1.0 second)
Factored uniform-hazard (2% probability of exceedance in 50 years) spectral acceleration.
Factored deterministic acceleration value. (1.0 second)
Factored deterministic acceleration value. (Peak Ground Acceleration)
Uniform-hazard (2% probability of exceedance in 50 years) Peak Ground Acceleration
Mapped value of the risk coefficient at short periods
Mapped value of the risk coefficient at a period of 1 s
Vertical coefficient
OSHPD PA2022-0295
DISCLAIMER
While the information presented on this website is believed to be correct, SEAOC /OSHPD and its sponsors and contributors assume no responsibility or liability for its
accuracy. The material presented in this web application should not be used or relied upon for any specific application without competent examination and verification of its
accuracy, suitability and applicability by engineers or other licensed professionals. SEAOC / OSHPD do not intend that the use of this information replace the sound judgment
of such competent professionals, having experience and knowledge in the field of practice, nor to substitute for the standard of care required of such professionals in
interpreting and applying the results of the seismic data provided by this website. Users of the information from this website assume all liability arising from such use. Use of
the output of this website does not imply approval by the governing building code bodies responsible for building code approval and interpretation for the building site
described by latitude/longitude location in the search results of this website.
PA2022-0295
SEISMIC FACTORS SM1 and So1
SM1 and S01 Calculations based on ASCE?-16
Site Class = D
S1 = 0.499
Long Period Site Coefficient, Fv
Site Class
C
D
S1 <= 0.1 S1 = 0.2 S1 = 0.3
1.5 1.5 1.5
2.4 2.2 2.0
Fv = 1.801
SM1 = Fv S1
-· 1.801 * 0.499
-0.899
= 2/3 * 0.899
= 0.599
S1 = 0.4
1.5
1.9
S1 = 0.5 S1 => 0.6
1.5 1.4
1.8 1.7
Geotechnical Engineering Investigation
6104 West Ocean Front
Newport Beach, California
Work Order 644322
Plate X
COAST GEOTECHNICAL, INC.
PA2022-0295
APPENDIX D
Records Review Report Pages
Geotechnical Engineering Investigation
6104 West Ocean Front
Newport Beach, California
COAST GEOTECHNICAL, INC.
PA2022-0295
!; m
·: f"l ·.,.I '...,.
~l Sladden Engineering
6782 Stanton Ave .. Suite E, Buena Park, CA 90621 (310) 864•4121 (714) 523-0952
December 16, 1996
Seaport Construction, Inc.
5 Upper Newport Plaza, Suite 200
Newport Beach, California 92660
Project Preliminary Soils Investigation
Fine Residence
6104West0ceanfront Drive
Newport Beach, California
Project No.444-6119
Presented herewith is the report of our Preliminary Soils rnvestigation conducted at the site of the
proposed residence ,o be located at 6104 West Oceanfront Drive in the City of Newport Beach,
California. The investigation was performed in order to provide recommendations for site
preparation and foundation design for the proposed residential structure.
This report presents the results of our field investigation and laboratory testing along with
conclu!;ions and recommendations for foundation design and site preparation. This report
completes our scope of services as described in our proposal dated November 13, 1996.
We appreciate the opportunity to provide-services to you on this projecL If you have any questions
regarding this report, please contact this office.
Copiet: 4-Seaport Construction, Inc.
PA2022-0295
INTRODUCTION
This report presents the results of a preliminary soils in\'estigation peri'ormed in order to provide
recommendations for the design and construction of the proposed residential building. The site of
the proposed pr0ject ii: located at 6104 West Oceanfront Drive in the City of Newport Beach,
California. It h our unclerstandi n g that the proposed residence will include two main stories and a
loft. The residence will be of wood-frame construction and will be supported by conventional
shallow spread footings.
SC'>PE OF WORK
The purpose of our investigation was to determine certain engineering characteristics of the near
surface soils on the site in order to develop recommendations for foundation design and site
preparation. Our investigation included field exploration, laboratory testing, literature review,
engineering analysis a11d the preparation of this report. Evaluation of hazardous wastes was not
within the scope of services provided. Our investigation was performed in accordance with
contemporary soils engineer'lg principles and practice. We make no other warranty, either
express or implied.
PROJECT DESCRIPTION
The proposed residence will be located on West Oceanfront Drive in The City of Newport Beach,
California. The project will include a two or three story residence of wood-frame construction.
The proposed residence wil I occupy approximately 3400 square feet.
It is our understanding that the proposed residence will be of lightweight wood-frame construction
and will be supported by conventional shallow spread footings and concrete slabs on grade.
Based upon expected foundation loading for similar structures, we assume that column loads will
be less than 30 kips and wall loads will be less than 3.0 kips per lin,ar foot. Grading will likely be
limited to removal and recompaction of the bearing soils within the building areas as recommended
in the Grading section of this report.
The residential lot is presently vacant and appears to have been recently cleared of a previous
residence. There are existing residences delineating the east and west sides of the lot. The beach is
directly south of the lot and the alley way forms the north side of the lot. The site is fairly level and
slightly lowe: in elevation than the adjacent beach. There are existing underground utilities within
the alley way and servicing the adjacent structures.
SITE SETTING
The site is located along the Pacific Ocean between the Santa Ana River and The Balboa Penisula in
the City of Newp011 Beach, California. The site is located at near sea level elevation adjacent to the
beach, Two computer programs were utilized to to compile data related to earthquake fault zones
in the region a11d previous seismic activity that may have affected the site. E.Q, Fault Version 2.1
(Blake 1989) provides a compilation of data related to earthquake faults in the region. The
program searches available databases and provides both distances to causitive faults and the
corresponding accelerations that may be experienced on the site due to earthquake activity along
these faults. The attenuation relationship utilized for this project was based upon Joyner & Boore
(1982) attenuation curves. E.Q. Search Version 2.1 (Blake 1989) provides a compilation of
previous earthquake activity that may have occurred in the area of the site. (n addition, the
accelerations thal may have been experienced in the area as a result of previous earthquake activity
are estimated. The output data from these programs is included in Appendix C.
December 16, 1996 ProjectNo444-6119
Sladden EnQlneering
PA2022-0295
• i t·
1111a
t,,
,.
L
• ic
i--h,
!!ill I J;':,
r-
""'
~ !
~-!
!Ill! f'
~H
Ii"
t' 11-,
~ i i:t•
,lollll '' lit;
~ w
~ ~
C
l
M ..
t
f"" i...
II'~
!
h..
,
"-
As indicated on the summary page of the E.Q. Fault output data, the site is very p .ar (0.2 miles
away) the 1'iewport-lnglewood Offshore Fault zone. The maximum credible site acce1eration is
estimated lo be 0.543g while the maximum probable site acceleration is estimated to be 0.280 ... As
indicated on the summary page of the E.Q. Search output data, the nearest documented hiitoric
earthquake was approximately cme mile from the site. The maxim11m site acceleration that has been
previously experienced at the site is estimated to be 0.36Sg .
SUBSURFACE CONDITIONS
The site is underlain primarily by slightly silty line grained sands overlying fine to coarse grained
sands. The sands underlying the site appeared fairly loose near the surface but very finn below a
depth of five feet. Sampler penetration driving resistance indicates the the deeper sands are very
firm. The site soils were typically dry within the upper five feet but wet near or below the present
groundwater level.
Laboratory classification testing indicates that the surface soils consist primarily of fine grained
sands. Expansion testing indicates an expansion index of O which falls witbin the "very low"
expansion category in accordance with the Uniform Building Code classification system.
Groundwater was encountered at a depth of approximately 10.5 feet below the existing gn;1und
surface. Groundwater should not be a factor in the design or construction of conventionafsfiallow
foundations.but groundwater should be expected to affect deeper excavations(i.e basements and
underground utilities.
CONCLUSIONS AND RECOMMENDATIONS
Based upon our field investigation and laboratory testing, it is our opinion that the proposed
development is feasible from a soil mechanic's standpoint provided that the recommendations
included in this report are considered in building foundation design and site preparation. Due to
the generally soft conditions of the near surface soils, remedial grading is recommended for
building slab and foundation areas. We recommend that remedial grading within the proposed
building areas include the removal and/or recompaction of the bearing soils. Moisture conditioning
is also recommended. Specific recommendations for site preparation are presented in the Site
Grading section of this report.
Groundwater was encountered within our borings at a depth of 10.S feet below the existing ground
surface. Due to the presence of groundwater, the potential for liquefaction affecting the site was
evaluated. The sands encountered below a depth of five feet were found to be quite dense
throughout the depth of our borings. Based upon the relativel)' dense condition of the sand layers
encountered below the present groundwater table, it is ourupinion that the potential for liquefaction
affectin,i the site is negligible,
Although a geologic evaluation was not within our scope of services, we feel that the owner and
designers should 6e aware of the project site setting and the related geologic and seismic hazards.
Designers should be aware of the potential for earthquoke activity during the anticipated life of the
structure. The site is localed very near the Newport-Inglewood Offshore Fault zone. Due to the
proximity of the Newport-Inglewood Offshore Fnult zone, the potential for ground rupture or
lurching should be acknowledged. Due to the proximity of the beach and the low lying nature of
the site, the potential for tsunamis affecting the site sh ... '·: also be acknowledged,
December 16, 1996 2 Project No444-6119
I . I I
I
\.
I
.... > .= ;
PA2022-0295
I"' jlj r
~ fi.1
!'Ill'
ii;
pill! ~;
,..
b!
APPENDIX A
FIELD EXPLORATION
For our field investigation, two exploratory borings were excavated using a truck mounted
hollow stem auger rig (Failing F-IO) at the approximate locations indicated on the site plan
included in this appendix. Continuous lots of the materials encountered were made on the site by
a representative of Sladden Engineering. !:Soring logs are included in this appendix.
Representative undisturbed samples were obtained within our borings by driving a thin-
walled steel penetration sampler (California split spoon sampler) or a standard penetration sampler
with a 140 pound hammer dropping approximately 30 inches. The number of blows required to
drive the sampler 18 inches were recorded in six inch increments and are indicated on the boring
Jogs. The California samplers are 3.0 inches in diameter, carrying brass sample rings having inner
diameters of 2.5 inches. The standard penetration samplers are 2.0 inches in diameter with an
inner diameter of 1.5 inches. Undisturbed samples were removed from the sampler and ()laced in
moisture sealed containers in order to preserve the natural sail moisture content. Samples were
then transported to our laboratory for further observations and testing.
December 16, 1996 7 Project No 444-6119
PA2022-0295
r----------------~
~ li;,J
m ILJ
u
~ iri,;j
flPPRO\i: I «tltT€ BoP.1 tJCo
Lciui11oN S
rl!'-----------------------------.-· ..
PA2022-0295
(JIii
~ t· ~~
6104 West Oceanfront Drive ..... ·-"· -...
19/96 Bol'ing No.: 1
·-r ----~----:-·. - . . i
0
10:
16 I
20 !·
-i.
30
311 , .
~o I I
I I DESCRIPTION
: Sand: Light brown, tine j grained, slightly silty
I
5/9/15 I ff ! r-... ···------·--------···-~-...
I I Sund: Light brown, fine
!21.,,,,2 :1 to coarse srainod, slightly silty
, ~.,, 9 , with scattered gravel and . · · &hells, compact ·
I I j
i17/ll0·2"
~1117/50-5"
••• 151110.3"
. .
SP
:
!
i
SP ii l,
IJ
92.0 1.5
18.3
20.4
19,1
15.0
17.3
18.3
14.0
I
I . ·1··········
i
i. 24,2
Job No.: 444-6119
REMARKS
81
'S/--· Free Water@ 10.5 foet
0l'avell.v
li 1·
·····•·--1~-·····-··•·····-··----------, I' ,' ... :I . -·····+•····· ·-··-·-··--======:::1 · · ·!TT~~i Depth--;GU•
: ! No Bedrock
' : Note: The 1tatifieation linea
· reprea8nt the approxiwatt-
boundariea between the aoil type1; '· the tr19fl' a be dual.
i
I
I
PA2022-0295
f4
"""'
6104 West Oceanfront Drive
Date: 11119/96
10 i
16
20'
26
30
315
40
415 i
!
1111
15118/24
'
DESCRIPTION
: Sand: Light brown, fine
grained, slightly silty
Sand: Light brown, fine
I to coarse grainod, slightly silty
with scattered gravel and
shells, compact
' ' ' I .. ·130/50-3" i •
1. 30/50-3" ;
. I
:1 li0-4"
I I !
:1\a.3"
ll~~ll~li''. .. , .......... , .. , .
I
-Recovered Sample
; •. j Standard Penetration
-·· Sample
:
j
I
REMARKS
SP !
;
I 96.0 3.1 •: 84
i .. ,
I I, 5.3 II SP :, ,,
j: + Froe Water@ 10.5 feet
i ' I I 13.0 I .I ,,
:1
i! :•
15.6
10,5 Ol'llvelly
l
': 14.0 · i Large rrravel and cobbles
1 I ! from 35 ta 40 feet
, Ii ·! 11 : i i 111.6 : i !
·.:::':i~:::::::::·~:::c·r ::.=·:::·::··. ·::.:.:::::::-i:1•-=.=:::::::::==========I . , , i I Total Depth = 41,5' i , , No Bedrock
:i
'
i Note: The atatillcation lin11 , reprecent the approxim•i"
1 · boundaries between the eoil t 1; ' t ..
PA2022-0295
i ,,
! bi
i:i ~,j
GEO-ETKA, INC.
ESfABLIStllW 1Sfl5
FOUNDATIOO SOIL INVESTIGATION, EN<llNEERING QE(JlOGY.
PAVEMENT OESfGN, 5LOPE STABlu~ ANALYSIS,
COMPACTIOO CONTRCl, PERCO!ATICIN STI.IOJES.
MATERIAL INSPECTICN ANO TESTING,
EfMROOMENTAL fNGINEEAING
ORANGE-MAIN BU$1NE6S PARK
739 N MAIN STREET • ORANGE, CA 92868-1105
(714) 771-e911 FAX {714) 771-1278
Februray 17, 1997
Job No: C-7924-96-97
Contractor and Client: Seaport const~uction, Inc.
5 Upper Newport Boulevard
Suite 200
contractor:
Architect:
Approving Agency:
owner and
Job Location:
Project:
Subject:
Date of Observation, Grading
and Testing:
Newport Beach, California 92660
Newport Excavating
Newport Beach, California
Mr. John M. Garcia
515-1/2 Goldenrod Avenue
Corona del Mar, Calif~rnia 92825
Department of Building and safety
3300 Newport Boulevard
City of Newport Beach, :a. 92658
Ms. Susan G. Fine
6104 West ocean Front
Newport Beach, California
single family resident
Compaction report for the
building pad
02-13-97
The following report contains the results of sand cone Density
Test Methods A.S.T,M. D-1556, and/or Nuclear Density Test Methods
0-2~22 and D-3017, Test numbers 1 through 13, taken on the sub-
ject project. Refer to the attached Plot Plan, Plate "B" for
location of the tests. The summary of the field density tests is
on Plate 11A11 •
1
PA2022-0295
-
...
i ·:
I'."!
.t t j
,i
:/L, ·1 0 /::\'. !
'.(?.,·.>::: .. J In w
a
n ~
□ Jtr:":· . l
t . ,.. -;J r~
_,',:-. ·.i liJ
i lr 4 l ~ .:...
GEO-ETKA, INC.
Job No: C-7924-96-97
Grading Notes
The building pad has been provided with 4 feet of compacted soil
tested to 90% of its relative dry density and is adequate for its
intended use.
Footing excavation observations, utility and retaining wall back-
fill, and subgrade testing for driveways and parking areas,
should be observed, tested and reported by GEO-ETICA, INC., as re-
quired by the approving agencies. spoils from the footings, if
placed on the pad, must be compacted to 90% and proofrolled prior
to the placement of concrete.
The grading and testing was performed in accordance with proce-
dures accepted by the governing agency, namely City of
Newport Beach, grading code. Those set forth in the preliminary
report, and generally practiced in the field of soil engineering.
Respectfully submitted,
GEO-ETKA, INC.
Javed s. Chak, P.E.
Geoteohnical Engineer
GE 197, Expires 12-31-97
~-~ I ., . \.. ' i~
Ahmed Ali, President
REA No. 04808
Expires 6-30-97
JSC/AA/ak
4
PA2022-0295
GEO-ETKA, INC.
WET SIGN Etllbllahed 1 NS
Soll Engineering, Geology And En,lronmental Engineering
Material Testing And Inspections
739 N. MAIN STREET. ORANGE. CALIFORNIA 92868
contractor and Client:
Architect:
Approving Agency:
owner and
Job Location:
Project:
Subject:
PHOM:: 014) 771-6911 FAX: (714) 771-1278
January 26, 1998
Job No: ENGR-7924-96-98
Seaport Construction, Inc.
5 Upper Newport Boulevard
Suite 200
Newport Beach, California 92660
Mr. John M. Garcia
515-1/2 Goldenrod Avenue
Corona del Mar, California 92825
Department o! Building and Safety
3300 Newport Boulevard
city of Newport Beach, ca. 92658
Ms. Susan G. Fine
6104 West Ocean Front
Newport Beach; California
single Family Resident
Summary and Final Report
The following is a summary of the reports t"'repared for this
project. The structure is nearly complete. This is a final
report.
Description
Ii! No 1 Job No. Bm;ioi;:t Date of }fork Don~
1. F-7924-96 l2-19M96 Preliminary soil
exploration report
2. C-7924-96-97 02-17-97 Compaction report
for the building
pad
3. o-7924-96-97 04-08-97 Footing excava-
tion, interior
sewer and pad
finish grade
testing
1
PA2022-0295
S. No. Job No.
4. D-7924A-96-98
GEO-ETKA, INC.
Job No: ENGR-7924-96-98
Description
Report Date of Wo;rk Done
01-23-98 Exterior utility
trench backfill
and flatwork
area testing
Following is a statement required by the city grading engineer.
All of the concrete flatwork has been completed for the subject
site, see Limited Report dated 1-23-98 for limitations.
The contractor, owner or his agent must provide copies of our
reports, specifically references 3 and 4.
All of the site earthwork has been completed in conformance with
the job specification generally accepted procedures and in accor-
dance wlth the grading code of the City of Newport Beach and,
hence, suitable for its intended use, namely a residential struc-
ture.
Respectfully Submitted, GEa:~• ~
Javed S. Chak, P.E.
Geotechnical Engineer
GE 197, Expires 12-31-99
~'-' 4 ~--
Ahmed Ali, President
REA No. 04808
Expires 6-30-98
JSC/AA/bg
2
PA2022-0295