HomeMy WebLinkAboutCT 2018-0006; LAGUNA DRIVE SUBDIVISION; PRELIMINARY GEOTECHNICAL INVESTIGATION; 2018-04-04_______ ,_,,.,., ______ -~-'--"'"~--.. ------------------------------
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COAST GEOTECHNICAL
CONSULTING ENGINEERS AND GEOWGISTS
April4,2018
Brett Farrow
Brett Farrow Architect
125 Mozart A venue
Cardiff, CA 92007
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MAY O 3 2018
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RE: PRELIMINARY GEOTECHNICAL INVESTIGATION
Proposed 12 Residential Structures
570-580 Laguna Drive
Carlsbad, CA 92008
Dear Mr. Farrow:
In response to your request and in accordance with our Agreement dated January 16, 2018, we have
performed a preliminary geotechnical investigation on the subject site for the proposed 12 residential
structures. The findings of the investigation, laboratory test results, and recommendations for the
foundation design are presented in this report.
From a geologic and soils engineering point of view, it is our opinion that the site is suitable for the
proposed development, provided the recommendations in this report are implemented during the
design and construction phases. However, certain geotechnical conditions will require special
consideration during the design and construction phases, as indicated by the following:
• The existing soil and weathered Paralic Deposits are not suitable for the support of proposed
footings, slabs-on-grade, exterior improvements or proposed fills in their present condition.
Remedial grading is recommended.
P.O. BOX 230163 • ENCINITAS, CALIFORNIA 92023 • (858) 755-8622
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• The rear inland bluff is composed, in part, of friable Paralic Deposits which are susceptible
to surficial failure and bluff retreat. Surface drainage should be directed, as much as
possible, away from the top of slope .
• The geologic conditions underlying the rear bluff are such that infiltrated water developing
saturated conditions can adversely affect slope stability. Stormwater infiltration should be
significantly limited and if necessary bioretention basins should be located in the most
southern portion of the site .
If you have any questions, please do not hesitate to contact us at (858) 755-8622. This opportunity
to be of service is appreciated .
11111 Respectfully submitted,
COAST GEOTECHNICAL ...
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Wyatt Bartholomew
Project Geologist
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PRELIMINARY GEOTECHNICAL INVESTIGATION
Proposed 12 Residential Structures
570-580 Laguna Drive
Carlsbad, CA 92008
Prepared/or:
Brett Farrow
Brett Farrow Architect
125 Mozart A venue
Cardiff, CA 92007
Prepared by:
COAST GEOTECHNICAL
P.O. Box 230163
Encinitas, CA 92023
April4,2018
w.o. 686218
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TABLE OF CONTENTS
1. INTRODUCTION ........................................................... 6
2. SCOPE OF SERVICES ...................................................... 6
3. SITE DESCRIPTION AND PROPOSED DEVELOPMENT ......................... 7
3 .1 Site Description .......................................................... 7
3 .2 Proposed Development .................................................... 7
4. SITE INVESTIGATION AND LABORATORY TESTING .......................... 8
4.1 Site Investigation ......................................................... 8
4.2 Laboratory Testing and Analysis ............................................ 8
4.3 Infiltration Testing ....................................................... 9
5. GEOLOGIC CONDITIONS ................................................... 9
5.1 Regional Geologic Setting ................................................. 9
5 .2 Site Geology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
5.3 Expansive Soil ......................................................... 11
5.4 Groundwater Conditions .................................................. 11
6. GEOLOGIC HAZARDS .................................................... 11
6.1 Faulting and Seismicity ................................................... 11
6.2 Landslide Potential ...................................................... 13
6.3 Liquefaction Potential .................................................... 14
6.4 Tsunami Potential ....................................................... 15
7. CONCLUSIONS ........................................................... 15
8. RECOMMENDATIONS .................................................... 16
8.1 Removals and Recompaction .............................................. 16
8.2 Temporary Slopes and Excavation Characteristics .............................. 17
8.3 Foundations ............................................................ 17
8.4 Sulfate and Chloride Tests ................................................ 18
8.5 Slabs on Grade (Interior and Exterior) ....................................... 18
8.6 Lateral Resistance ....................................................... 19
8.7 Retaining Walls ......................................................... 19
8.8 Dynamic (Seismic) Lateral Earth Pressures ................................... 20
8.9 Settlement Characteristics ................................................. 21
8.10 Seismic Considerations .................................................. 21
8.11 Preliminary Pavement Design ............................................. 22
8.12 Permeable Interlocking Concrete Pavers (PICP) .............................. 23
8.13 Utility Trench ......................................................... 24
8.14 Drainage ............................................................. 24
8.15 Geotechnical Observations ............................................... 25
8.16 Plan Review .......................................................... 25
9. LIMITATIONS ......................................................... 25
REFERENCES ............................................................... 27
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COAST GEOTECHNICAL
APPENDIX A
Figure 1:
Figure 2:
Figure 3:
Figure 4:
Figure 5:
Figure 6:
Plate A:
Plate B:
APPENDIXB
Location Map
Geotechnical Map
Cross Section A-A"
Borehole Log No. 1
Borehole Log No. 2
Regional Fault Map
Typical Isolation Joints and Re-Entrant Corner Reinforcement
Typical Permeable Paver Detail
Laboratory Test Results
Figure 7: Infiltration Test Graph
Seismic Design Parameters
Design Response Spectrum
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Slope Stability Analysis
APPENDIXD
Grading Guidelines
Brett Farrow
w.o. 686218
Page 5 of28
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COAST GEOTECHNICAL
1. INTRODUCTION
Brett Farrow
w.o. 686218
Page 6 of28
This report presents the results of our background review, subsurface investigation, laboratory
testing, geotechnical analyses, conclusions regarding the conditions at 570-580 Laguna Drive, and
recommendations for design and construction. The purpose of this study is to evaluate the nature
and characteristics of the earth materials underlying the property, the engineering properties of the
surficial deposits and their influence on the proposed 12 residential structures .
2. SCOPE OF SERVICES
The scope of services provided included a review of background data, reconnaissance of the site
geology, and engineering analysis with regard to the proposed. The performed tasks specifically
included the following:
• Reviewing geologic and hazard (seismic, landslide, and tsunami) maps, recently published
regarding the seismic potential of nearby faults, and a site plan for the project. All
background data is listed in the References portion of this report.
• Performing a site reconnaissance, including the observation of geologic conditions and other
hazards, which may impact the proposed project.
• Excavation of exploratory borings consisting of excavating, logging, and sampling of earth
materials to evaluate the subsurface conditions.
• Performing geotechnical laboratory testing of recovered soil samples.
• Analyzing data obtained from our research, subsurface exploration, and laboratory and
infiltration testing.
• Preparing this preliminary report.
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COAST GEOTECHNICAL
3. SITE DESCRIPTION AND PROPOSED DEVELOPMENT
3.1 Site Description
Brett Farrow
w.o. 686218
Page 7 of28
The subject site is a partially developed lot on Laguna Drive in the city of Carlsbad (Figure 1). The
northwest quadrant of the lot is vacant, the southeast quadrant of the lot is developed with a small
building, the northeast and southeast quadrant hosts an existing building and the remainder of the
lot is paved with asphalt. The property is a polygonal-shaped area that descends gently to the
northwest and is bounded by an inland bluff that descends to Buena Vista Lagoon. The elevation
of the lot ranges from approximately 5.0 to 45 feet.
The subject site includes an existing residence, existing office building, and two existing AC parking
areas. The lot is relatively flat ranging from 40 to 43 feet as you move north to south along the
property. The northern portion of the property is bounded by an inland bluff that descends to the
Buena Vista Lagoon at a gradient approaching 1 ¼: 1 (horizontal to vertical) for approximately 40
vertical feet. The site is bounded along the north by Buena Vista Lagoon, to the south by Laguna
Drive, and to the east and west by developed residential lots.
Vegetation on the site consists of trees and shrubs. Drainage is generally by sheet flow to the
northwest in the direction of the inland bluff and Buena Vista Lagoon.
3.2 Proposed Development
A topographic plat of the site was prepared by Sampo Engineering. Preliminary architectural plans
for the development of the site were prepared by Brett Farrow, Architect. The project is anticipated
to include the demolition of the most southeastern existing building, but not the northeastern
structure, and the construction of 12 residential structures with one car garages (Figure 2). Grading
plans were not available during the assessment of the lot, but due to the relatively flat nature of the
existing lot, we presume grading to be minimal.
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COAST GEOTECHNICAL
4. SITE INVESTIGATION AND LABORATORY TESTING
4.1 Site Investigation
Brett Farrow
w.o. 686218
Page 8 of28
Site exploration was performed on March 16, 2018. It included a visual reconnaissance of the site
and the excavation of two (2) exploratory boreholes (Figures 4-5). The boreholes were drilled using
a truck-mounted hollow-stem auger. Samples were obtained using a modified California Sampler
and SPT Sampler. All the borings were extended through the underlying top soil, Old Paralic
Deposits and into the underlying Santiago Formation to maximum depths 50 feet in Borehole 1 and
30 feet in Borehole 2. Earth materials encountered were visually classified and logged by our field
project geologist, and sampled for future laboratory testing. Undisturbed, representative samples of
earth materials were obtained at selective intervals by driving a thin-walled steel sampler into the
desired strata with a 140 pound hammer powered by a cathead and rope system. Bulk samples were
also obtained at selected intervals. Samples are retained in waterproof containers and brass rings and
transported to Coast Geotechnical Soils Laboratory for testing and analysis.
The site investigation also included a visual observation of the surrounding landscape of the project
site. Existing wood retaining walls are in place along the slope into the lagoon.
4.2 Laboratory Testing and Analysis
The laboratory tests were performed in accordance with the generally accepted American Society
for Testing and Materials (ASTM) test methods or suggested procedures. All lab descriptions and
results can be found in the Test Results section of Appendix B of this report.
The following tests were preformed:
• Classification of Soils
• Grain Size Distribution
• Moisture/Density
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COAST GEOTECHNICAL
• Maximum Dry Density and Optimum Moisture Content
• Expansion Index Test
• Sulfate Ion Content
• Chloride Ion Content
• pH Test
• Field Resistivity Test
• Shear Test
• Infiltration Test
4. 3 Infiltration Testing
Brett Farrow
w.o. 686218
Page 9 of28
Infiltration testing was performed using a Double-Ring lnfiltrometer (ASTM D3385). The
infiltration test area is located in the southern portion of the site as indicated on the enclosed
Geotechnical Map. The area was prepared by excavating down to the Paralic Deposits. A level pad
was established for testing. Infiltration results can be found in the Test Results section of Appendix
B of this report as Figures 7 (Infiltration Test Log) and 8 (Infiltration Test Graph).
5. GEOLOGIC CONDITIONS
The geologic conditions at the site are based on our field exploration and review of available
geologic and geotechnical literature .
5.1 Regional Geologic Settings
The subject property is located in the Coastal Plains subdivision of the Peninsular Ranges
geomorphic province of San Diego. The coastal plain area is characterized by Pleistocene marine
terrace landforms. These surfaces are relatively flat erosional platforms that were shaped by wave
action along the former coastlines. The step-like elevation of the marine terraces was caused by
changes in sea level throughout the Pleistocene and by seismic activity along the Newport-Inglewood
Fault Zone located 4.5 miles west of the coastline. The Newport-Inglewood Fault Zone is one of
many northwest trending, sub-parallel faults and fault zones that traverse the nearby vicinity. Several
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COAST GEOTECHNICAL Brett Farrow
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of these faults, including the Rose Canyon Fault Zone, are considered active faults. Further
discussion of faulting in regards to the site is discussed in the Geologic Hazards section of this
report.
5.2 Site Geology
Previously published geologic maps conducted by Kennedy and Tan (2008) suggest that the subject
property is underlain at depth by the Santiago Formation (Tsa) and Old Paralic Deposits (Qop) .
Overlying the rocks is Top Soil (Qs). The Old Paralic Deposits are covered by Top Soil (Qs) along
the surface of the property site as encountered in Boring Nos. 1 and 2 (B-1 and B-2). The general
geologic conditions are depicted on cross-section A-A" enclosed on Figure 3. A brief description
of the earth materials encountered on the site are as follows:
• Top Soil (Qs)
In Borehole Nos. 1 and 2 (B-1 and B-2), 2.5 to 2 feet of Top Soil was encountered,
respectively. The Top Soil is a reddish dark brown, fine grained, extremely well sorted,
moderately dense sand and has an organic odor.
• Old Paralic Deposits (Qop)
Approximately 17 feet and 18 feet of Paralic sediments were encountered in Borehole Nos.
1 and 2 (B-1 and B-2) respectively. In Borehole 1, from 2.5 feet to 11.5 feet and in Borehole
2, from 2 feet to 11.5 feet, the sediments are tan reddish brown, fine and medium grained
sandstone, slightly moist and moderately dense. From 11.5 feet to 16 feet in Borehole 1 and
11.5 feet to 15 feet in Borehole 2, the sediments are light brownish tan to red brown fine-
grained sandstone, well sorted, dense, slightly moist and contain rounded gray pebbles. It's
important to note the gravel layer was penetrated in both boreholes at an approximate depth
between 13 to 17 feet. In Borehole 1 from 16 feet to 19 feet and Borehole 2 from 15 feet to
19.5 feet, the sediments encountered were tan to light orange to red brown coarse to fine-
grained sandstone, slightly moist and moderately dense.
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• Santiago Formation (Tsa)
Brett Farrow
w.o. 686218
Page 11 of28
Underlying the Old Paralic Deposits is the Santiago Formation. This formation of
interbedded sands and clays was encountered at a depth of 19 feet in Borehole 1 and 19 .5 feet
in Borehole 2 and extended to the maximum depths of 50 feet and 30 feet in Boreholes 1 and
2, respectively. It consists of gray to pale green to white clayey fine to coarse grained
sandstone and is very dense and slightly moist.
5. 3 Expansive Soil
Based on our experience in the area and previous laboratory testing of selected samples, the Paralic
deposits reflect an expansion potential in the low range .
5. 4 Groundwater Conditions
No evidence of perched or high groundwater tables were encountered to the depth explored .
However, the upper Paralic Deposits are pervious and the underlying Santiago Formation is
relatively impervious suggesting that perched groundwater conditions can develop from infiltration
of water. It should be noted that seepage problems can develop after completion of construction.
These seepage problems most often result from drainage alterations, landscaping, and over-irrigation.
In the event that seepage or saturated ground does occur, it has been our experience that they are
most effectively handled on an individual basis.
6. GEOLOGIC HAZARDS
6.1 Faulting and Seismicity
The subject site is located within the seismically active Southern California region, which is
generally characterized by northwest trending, right-lateral strike-slip faults and fault zones. Several
of these fault segments and zones are classified as active by the California Geologic Survey
(Alquist-Priolo Earthquake Fault Zoning Act.). As a result, ground shaking is a potential hazard
throughout the region .
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Brett Farrow
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Based on a review of published geologic maps, no known active faults traverse the site (Figure 6).
Thus, ground surface rupture is not likely to occur as a result of an earthquake or seismic event.
The nearest active fault to the site is the Newport Inglewood Fault (offshore), located approximately
4.5 miles west of the site. It should be noted that the Newport Inglewood Fault is one of four main
fault strands that make up the Newport-Inglewood/Rose Canyon (NIRC) fault system (Treiman,
1984 ). The four strands form a series of right-stepping en echelon faults situated along the Southern
California coastline. A recent study by Sahakian et al. (2017) concluded that the geometry of the
NIRC fault system may enable rupture along the entire length of the fault zone. The study also
modeled several rupture scenarios in light of the newly defined geometry which suggest earthquake
ruptures up to magnitudes (M) of 7.4 are possible along the NIRC system. While the models are
intriguing, the paper recommends further research and modeling on the NIRC fault geometry to
improve our understanding of potential hazards and ground shaking along the Southern California
coast. Therefore, the modeled rupture magnitude ofM = 7.4 on the Rose Canyon Fault was not used
for the recommendations for this investigation.
Other nearby faults that may affect the site include the Rose Canyon, Coronado Bank, Temecula and
Julian Faults. The proximity of major faults to the site, and their estimated maximum earthquake
magnitudes and peak site accelerations are enclosed on Table 1 and were determined by EQF AULT
version 3.00 software (Blake, 2000).
COAST GEOTECHNICAL
Table 1: Principal Active Faults
Fault Name
Approximate Distance
from site (mi)
Newport-Inglewood 4.5
Rose Canyon 4.8
Elsinore-Temecula 20.9
Elsinore-Julian 24.1
Elsinore-Glen Ivy 24.5
Palos Verdes 33.0
Earthquake Valley 34.9
Newport-Inglewood 44.6
San Jacinto-Anza 45.0
MaximwnEQ
Magnitude (Mmax)
6.9
6.9
7.4
6.8
7.1
6.8
7.1
6.5
6.9
Brett Farrow
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Page 13 of28
Peak Site
Accel. (g)
0.388
0.381
0.223
0.152
0.174
0.116
0.131
0.072
0.092
The Rose Canyon Fault is capable of generating a magnitude earthquake which would cause strong
ground motions at the subject site. Further analysis on seismicity and the site specific seismic
parameters are discussed in the Recommendations chapter of this report.
6. 2 Landslide Potential
A landslide is the displacement of a mass of rock, debris, or earth down a slope caused by
topographic, geological, geotechnical and/or subsurface water conditions. Potential landslide
hazards for the site were assessed using the review of published geologic and topographic maps as
well as subsurface exploration.
According to the Landslide Hazards map, San Luis Ray Quadrangle (Tan and Giffen, 1995), the site
is located within Susceptibility Area 3-1 where slopes are generally susceptible. Most slopes in this
area do not contain landslide deposits, but they can be subject to surficial failure and bluff retreat as
discussed below.
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COAST GEOTECHNICAL Brett Farrow
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Page 14 of28
The rear bluff descends at a gradient approaching 1 ¼: 1 (horizontal to vertical) for approximately 40
vertical feet and is underlain by two (2) major geologic units with different characteristics.
The upper 20 feet of the rear bluff is composed of Pleistocene-age sediments that are weakly
cemented and friable along slope faces. These fine-grained sands are subject to surficial failures and
bluff retreat. Wood batter boards have been installed in the slope to retard surficial slippage with
limited success.
Underlying the coastal bluff sediments, Eocene-age sedimentary units which have commonly been
correlated with the Santiago Formation are present. The sedimentary rock is primarily composed
of dense to very dense clayey sandstone. Although claystone units within the Santiago Formation
have been associated with landslides, no evidence of deep-seated instability was observed in the
exploratory borings or site topographic expression .
Slope stability analysis utilizing GST ABL 7 with STEDwin suggests the most critical failure surface
is primarily within the upper Pleistocene Old Paralic Deposits. Static and Pseudo-static stability
analyses are shown on the enclosed Stability Analysis Appendix C .
6. 3 Liquefaction Potential
Liquefaction is a process by which a sand mass loses its shearing strength completely and flows. The
temporary transformation of the material into a fluid mass is often associated with ground motion
resulting from an earthquake, and high groundwater conditions.
The fifty (50) foot deep boring (B-1) suggests that the Paralic Deposits are in a medium-dense to
dense condition and the underlying sedimentary units of the Santiago Formation are in a very dense
condition. Groundwater was not encountered to a depth of 50 feet below existing ground surface.
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COAST GEOTECHNICAL Brett Farrow
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Owing to the moderately dense to very dense nature of the geologic formations and the anticipated
depth to groundwater, the potential for seismically-induced liquefaction and soil instability is
considered low .
6. 4 Tsunami Potential
Tsunamis are large sea waves generated by earthquakes, volcanic eruptions, or landslides that
potentially cause the displacement of substantial volumes of water .
The Tsunami Inundation Map for Emergency Planning: San Luis Ray Quadrangle (California
Emergency Management Agency, 2009) suggests that the site is not susceptible to flooding from
tsunamis.
7. CONCLUSIONS
• No geologic hazards such as faulting, liquefaction or deep-seated instability which could
preclude development were encountered on the site.
• The rear slope is composed of friable Pleistocene sediments which are subject to erosion,
surficial failure and retreat during prolonged rainfall and drainage directed toward the top of
the slope.
• Design plans should consider raising the proposed pad grades such that drainage is directed
to the south away from the top of the bluff .
• The geologic conditions underlying the rear bluff are such that infiltrated water developing
saturated conditions can adversely affect slope stability. Storm water infiltration should be
significantly limited and, if necessary, bioretention basins should be located inn the most
southern portion of the site .
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COAST GEOTECHNICAL Brett Farrow
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• The existing soil and weathered Paralic Deposits are not suitable for the support of proposed
footings, slab-on-grade, exterior improvements or proposed fills in their present condition.
These deposits should be removed and replaced as properly compacted fill .
• Disturbed soils resulting from the demolition of structures and utility lines should be
removed and replaced as properly compacted fill.
• Prior to the double-ring infiltration test, the area was excavated into the Old Paralic Deposits
about the 42 foot elevation. Testing in the area of the site (IF-I) was conducted in the Paralic
Deposit and reflected a stabilized infiltration rate approaching that of2.48 inches per hour .
8. RECOMMENDATIONS
8.1 Removals and Recompaction
The existing soil and weathered Old Paralic Deposits in the building pad should be removed and
replace as properly compacted fill. Removals in building pads should extend a minimum of 5.0 feet
beyond the building footprint or the entire building pad depending upon final design plans. The
depth of removals are anticipated to be on the order of 3 .0 feet in building pads. Most of the existing
earth deposits are generally suitable for reuse, provided they are cleared of all vegetation, debris, and
thoroughly mixed. Prior to placement of fill, the base of the removal should be observed by a
representative of this firm. Additional overexcavation and recommendations may be necessary at
that time. The exposed bottom should be scarified to a minimum depth of 6.0 inches, moistened as
required, and compacted to a minimum of 90 percent the laboratory maximum dry density. Fill
should be placed in 6.0 to 8.0 inch lifts, moistened to approximately 1.0-2.0 percent above optimum
moisture content and compaction to a minimum of 90 percent the laboratory maximum dry density.
Soil and weathered Paralic Deposits in areas of proposed concrete flatwork, exterior improvements,
and driveways should be removed and replaced as properly compacted fill. Imported fill, if
necessary, should consist of non-expansive granular deposits approved by the geotechnical engineer.
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8.2 Temporary Slopes and Excavation Characteristics
Brett Farrow
w.o. 686218
Page 17 of28
Temporary excavation, which expose soil and weathered Paralic Deposits should be trimmed to a
gradient of 1: 1 (horizontal to vertical) or less depending upon conditions encountered during grading .
The Old Paralic Deposits may be excavated to a vertical height of 5.0 feet. The temporary slope
recommendations assume no surcharges are located or will be placed along the top of the slope
within a horizontal distance equal to one half the height of the slope. The Paralic Deposits are dense
below the weathered zone. However, based on our experience in the area, the Paralic Deposits are
rippable with conventional heavy moving equipment in good working order .
8.3 Foundations
The following design parameters are based on footings founded into non-expansive approved
compacted fill deposits or competent Paralic Deposits. Footings for the proposed structure should
be a minimum of 12 inches and 15 inches wide and founded a minimum of 12 inches and 18 inches
below the lower most adjacent subgrade at the time of foundation construction for single-story and
two-story structures, respectively. A 12 inch by 12 inch grade beam or footing should be placed
across the garage opening. Footings should be reinforced with a minimum of four No. 4 bars, two
along the top of the footing and two along the base. Where parallel wall footings occur, the upper
footing should be deepened below a 45 degree plane projected up from the base of the lower footing,
or the lower wall should be designed for the additional surcharge load from the upper wall. Footing
recommendations provided herein are based upon underlying soil conditions and are not intended
to be in lieu of the project structural engineer's design .
The base of footings should be maintained a minimum horizontal distance of 10 lateral feet to the
face of the nearest slope .
For design purposes, an allowable bearing value of 2000 pounds per square foot and 2400 pounds
per square foot may be used for foundations at the recommended footing depths for single and two
story structures, respectively .
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COAST GEOTECHNICAL Brett Farrow
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For footings deeper than 18 inches, the bearing value may be increased by 250 pounds per square
foot for each additional 6.0 inches of embedment to a maximum of 3000 pounds per square foot.
The bearing value may be increased by one-third for the short durations of loading, which includes
the effects of wind and seismic forces.
The bearing value indicated above is for the total dead and frequently applied live loads. This value
may be increased by 33 percent for short durations of loading, including the effects of wind and
seismic forces .
8.4 Sulfate and Chloride Tests
The results of our sulfate and chloride tests performed on representative samples are presented on
Tables 8 and 9 in Appendix B. The test results suggest a sulfate content of 0.005 (negligible).
8. 5 Slabs on Grade (Interior and Exterior)
Slab on grade should be a minimum of 5.0 inches thick and reinforced in both directions with No.
3 bars placed 18 inches on center in both directions. Exterior slabs on grade should be a minimum
of 4.5 inches thick and reinforced with No. 3 placed 18 inches on center in both directions. The slab
should be underlain by a minimum 2.0-inch coarse sand blanket (S.E. greater than 30). Where
( moisture sensitive floors are used, a minimum 10.0-mil Visqueen, Stego, or equivalent moisture
barrier should be placed over the sand blanket and covered by an additional two inches of sand (S.E. -.. -II -.. ..
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greater than 30). Utility trenches underlying the slab may be backfilled with on-site materials,
compacted to a minimum of 90 percent of the laboratory maximum dry density. Slabs should be
reinforced as indicated above the provided with saw cuts/expansion joints, as recommended by the
project structural engineer. All slabs should be cast over dense compacted subgrades. At a
minimum, interior slabs should be provided with softcut contraction/control joints consisting of
sawcuts spaced 10 feet on center maximum each way. Cut as soon as the slab will support the
weight of the saw, and operate without disturbing the final finish, which is normally within 2 hours
after final finish at each control joint location or 150 psi to 800 psi. The softcuts should be a
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COAST GEOTECHNICAL Brett Farrow
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minimum of 3/4 inch in depth, but should not exceed 1 inch deep maximum. Anti-ravel skid plates
should be used and replaced with each blade to avoid spalling and raveling. A void wheeled
equipment across cuts for at least 24 hours. Provide re-entrant comer (270 degrees comers)
reinforced for all interior slabs consisting of minimum two, IO-feet long No. 3 bars at 12 inches on
center with the first bat placed 3 inches from re-entrant comer (see Plate F). Re-entrant comers will
depend on slab geometry and/or interior column locations. Exterior slabs should be provided with
weakened plane joints at frequent intervals in accordance with the American Concrete Institute (ACI)
guidelines.
Our experience indicates that the use of reinforcement in slabs and foundations can reduce the
potential for drying and shrinkage cracking. However, some minor cracking is considered normal
and should be expected as the concrete cures. Moisture barriers can retard, but not eliminate
moisture vapor movement from the underlying soils up through the slab.
8. 6 Lateral Resistance
Resistance to lateral load may be provided by friction acting at the base foundations and by passive
earth pressure. A coefficient of friction of 0.25 may be used with dead-load forces. Design passive
earth resistance may be calculated from a lateral pressure corresponding to an equivalent fluid
density of 300 pounds per cubic foot with a maximum of2500 pounds per square foot.
8. 7 Retaining Walls
Cantilever walls (yielding) retaining nonexpansive granular soils may be designed for an
active-equivalent fluid pressure of 37 pounds per cubic foot for a level surcharge and 45 pounds per
cubic foot for a sloping backfill. Restrained walls (nonyielding) should be designed for an "at-rest"
equivalent fluid pressure of 60 pounds per cubic foot. Wall footings should be designed in
accordance with the foundation design recommendations. All retaining walls should be provided
with adequate backdrainage system. A geocomposite blanket drain such as Miradrain 6000 or
equivalent is recommended behind walls. The soil parameters assume a level nonexpansive select
granular backfill compacted to a minimum of90 percent of the laboratory maximum dry density.
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COAST GEOTECHNICAL
8.8 Dynamic (Seismic) Lateral Earth Pressures
Brett Farrow
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Page 20 of28
For proposed restrained walls (non-yielding), potential seismic loading should be considered. For
smooth rigid walls, Wood (1973) expressed the dynamic thrust in the following form:
~Pe= khyH2 (nonyielding)
where kh is ½ peak ground acceleration equal to 50 percent of the design spectral response
acceleration coefficient (Sds) divided by 2.5 per C.B.C. (2007), 'Y is equal to the unit weight of
backfill, and H is equal to the height of the wall.
The pressure diagram for this dynamic component can be approximated as an inverted trapezoid with
stress decreasing with depth. The point of application of the dynamic thrust is at a height of 0.6
above the base of the wall. The magnitude of the resultant is:
~Pe = 20.3 H2 (nonyielding)
This dynamic component should be added to the at-rest static pressure for seismic loading '
conditions.
For cantilever walls (yielding), Seed and Whitman (1970) developed the dynamic thrust as:
~Pe= 3/8 khyH2 (yielding)
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COAST GEOTECHNICAL Brett Farrow
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Page 21 of28
The pressure diagram for this dynamic component can be approximated as an inverted trapezoid with
stress decreasing with depth and the resultant at a height of 0.6 above the base of the wall. The
magnitude of the resultant is:
~Pe = 7 .62 H2 (yielding)
This dynamic component should be added to the static pressure for seismic loading conditions.
8. 9 Settlement Characteristics
Estimated total and differential settlement over a horizontal distance of 30 feet is expected to be on
the order of 1.0 inch and¾ inch, respectively. It should also be noted that long term secondary
settlement due to irrigation and loads imposed by structures is anticipated to be ¼ inch.
8.10 Seismic Considerations
Although the likelihood of ground rupture on the site is remote, the property will be exposed to
moderate to high levels of ground motion resulting from the release of energy should an earthquake
occur along the numerous known and unknown faults in the region. The Newport-Inglewood
(offshore) Fault Zone located approximately 4.5 miles west of the property is the nearest known
active fault, and is considered the design fault for the site. In addition to the Newport-Inglewood
fault, several other active faults may affect the subject site.
Seismic design parameters were determined as part of this investigation in accordance with Chapter
16, Section 1613 of the 2016 California Building Code ( CBC) and ASCE 7-10 Standard using the
web-based United States Geological Survey (USGS) Seismic Design Tool. The generated results
for the parameters are presented on Table 2.
COAST GEOTECHNICAL
Table 2: Seismic Design Parameters
Factors
Site Class
Seismic Design Category
Site Coefficient, Fa
Site Coefficient, F v
Mapped Short Period Spectral Acceleration, Ss
Mapped One-Period Spectral Acceleration, S1
Short Period Spectral Acceleration Adjusted for Site Class, SMs
One-Second Period Spectral Acceleration Adjusted for Site, SM1
Design Short Period Spectral Acceleration, S0s
Design One-Second Period Spectral Acceleration, S01
8.11 Preliminary Pavement Design
Brett Farrow
w.o. 686218
Page 22 of28
Values
D
I/II/III
1.037
1.556
1.158
0.444
1.201 g
0.691 g
0.800 g
0.461 g
The following preliminary pavement section is recommended for proposed driveways:
• 4.0 inches of asphaltic concrete on
• 6.0 inches of select base (Class 2) on
• 12 inches of compacted subgrade soils or
• 5.5 inches of concrete on
• 12 inches of compacted subgrade soils
Subgrade soils should be compacted to the thickness indicated in the structural section and left in
a condition to receive base materials. Class 2 base materials should have a minimum R-value of78
and a minimum sand equivalent of 30. Subgrade soils and base materials should be compacted to
a minimum of95 percent of their laboratory maximum dry density. Concrete should be reinforced
with No. 3 bars placed 18 inches on center in both directions.
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COAST GEOTECHNICAL Brett Farrow
w.o. 686218
Page 23 of28
The pavement section should be protected from water sources. Migration of water into subgrade
deposits and base materials could result in pavement failure.
8.12 Permeable Interlocking Concrete Pavers (P ICP)
Permeable Interlocking Concrete Pavers (PICP), if proposed, should consider several design aspects.
Foundations adjacent to or in close proximity to PICP should be protected by an impervious
membrane extending a minimum of 3.0 lateral feet from the foundation under the pavement section.
The intent is to reduce lateral migration of infiltrated drainage and potential impact on footings.
However, this approach is considered less desirable from a geotechnical viewpoint than lining the
entire section with an impervious liner.
Pavement underdrains are recommended and should be incorporated in the design for proper
collection and disposal of filtrated storm water as indicated on Plate G. If subdrains are not allowed
for storm water infiltration by reviewing agencies, the long term effects of infiltrated water on
structural foundations and slabs cannot be predicted with any degree of certainty.
PICP pavement structural section (Driveways) should consist of 31/s inch PICP, over a minimum of
2.0 inches of ASTM No. 8 bedding course/choke stone, over a minimum of 8.0 inches of ASTM No.
57 stone base course, over a minimum of 12 inches of 95 percent compacted subgrade. Bedding
course/choke stone and base course stone should also be well compacted, consolidated, and
interlocked (avoid crushing the underdrain pipes) with heavy construction equipment. ASTM No.
8, No. 9 or No. 89 should be used for joint materials, depending on the joint size and per
manufacturer recommendations. The above stone base section may be reduced from 12 inches to
a minimum of 6.0 inches for walkways and patios, if desired. The gradational requirements are
summarized on Table 3 .
COAST GEOTECHNICAL Brett Farrow
w.o. 686218
Page 24 of28
Table 3: Gradational Requirements for ASMT No. 57, No. 8, No. 89, and No. 9
Sieve Percent Passing
Size No. 57 No. 8 No. 89 No.9
l ½" 100 ------
l" 95 to 100 ------
½" 25 to 60 100 100 --
3/a" --85 to 100 90 to 100 100
No.4 0 to 10 10 to 30 20 to 55 85 to 100
No. 8 0 to 5 0 to 10 5 to 30 10 to 40
No. 16 --0 to 5 0 to 10 0 to 10
No. 50 ----0 to 5 0 to 5
8.13 Utility Trench
We recommend that all utilities be bedded in clean sand to at least one foot above the top of the
conduit. The bedding should be flooded in place to fill all the voids around the conduit. Imported
or on-site granular material compacted to at least 90 percent relative compaction may be utilized for
backfill above the bedding.
The invert of subsurface utility excavations paralleling footings should be located above the zone
of influence of these adjacent footings. This zone of influence is defined as the area below a 45
degree plane projected down from the nearest bottom edge of an adjacent footing. This can be
accomplished by either deepening the footing, raising the invert elevation of the utility, or moving
the utility or the footing away from one another.
8.14 Drainage
Specific drainage patterns should be designated by the project architect or engineer. However, in
general, pad water should be directed away from foundations and around the structure to the street.
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COAST GEOTECHNICAL Brett Farrow
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Page 25 of28
Roof water should be collected and conducted to the street via non-erodible devices. Pad water
should not be allowed to pond. Vegetation adjacent to foundations should be avoided. If vegetation
in these areas is desired, sealed planter boxes or drought resistant plants should be considered. Other
alternative may be available, however, the intent is to reduce moisture from migrating into
foundation subsoils. Irrigation should be limited to that amount necessary to sustain plant life. All
drainage systems should be inspected and cleaned annually, prior to winter rains .
8.15 Geotechnical Observations
Structural footing excavations should be observed by a representative of this firm prior to the
placement of steel and forms. All fill should be placed while a representative of the geotechnical
engineering is present to observe and test.
8.16 Plan Review
A copy of the final plans should be submitted to this office for review prior to the initiation of
constructions. Additional recommendations may be necessary at that time .
9. LIMITATIONS
This report is presented with the provision that it is the responsibility of the owner or the owner's
representative to bring the information and recommendations given herein to the attention of the
project's architects and/or engineers so that they may be incorporated into the plans.
If conditions encountered during construction appear to differ from those described in this report,
our office should be notified so that we may consider whether modifications are needed. No
responsibility for construction compliance with design concepts, specifications, or recommendations
given in this report is assumed unless on-site review is performed during the course of construction .
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Brett Farrow
w.o. 686218
Page 26 of28
The subsurface conditions, excavation characteristics, and geologic structure described herein are
based on individual exploratory excavations made on the subject property. The subsurface
conditions, excavation characteristics, and geologic structures discussed should in no way be
construed to reflect any variations which may occur among the exploratory excavations .
Please note that fluctuations in the level of groundwater may occur due to variations in rainfall,
temperature, and other factors not evident at the time measurements were made and reported herein.
Coast Geotechnical assumes no responsibility for variations which may occur across the site .
The conclusions and recommendations of this report apply as of the current date. In time, however,
changes can occur on a property whether caused by acts of man or nature on this or adjoining
properties. Additionally, changes in professional standards may be brought about by legislation or
the expansion of knowledge. Consequently, the conclusions and recommendations of this report
may be rendered wholly or partially invalid by event beyond our control. This report is therefore
subject to review and should not be relied upon after the passage of two years.
The professional judgements presented herein are founded partly on our assessment of the technical
data gathered, partly on our understanding of the proposed construction, and partly on our general
experience in the geotechnical field. However, in no respect do we guarantee the outcome of the
project.
This study has been provided solely for the benefit of the client, and is in no way intended to benefit
or extend any right or interest to any third party. This report is not to be used on other projects or
extensions to this project except by agreement in writing with Coast Geotechnical.
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COAST GEOTECHNICAL
REFERENCES
Brett Farrow
w.o. 686218
Page 27 of28
Blake, T. F. (2000). EQFAULT: A Computer Program for the Deterministic Estimation of Peak
Acceleration using Three-Dimensional California Faults as Earthquake Sources, Version 3.0,
Thomas F. Blake Computer Services and Software, Thousand Oaks, CA.
California Building Standards Commission. (January 1, 2016). 2016 California Building Code,
California Code of Regulations .
California Emergency Management Agency, California Geological Survey, and University of
Southern California. (2009). Tsunami Inundation Map for Emergency Planning: San Luis Rey
Quadrangle, California, San Diego County, Scale 1 :24,000 .
California Geologic Survey, (1994), Fault Activity Map of California, Map Scale 1 "=750,00' .
Gregory Geotechnical Software, OST ABL 7 with STEDwin (1996, 1999). Slope Stability Analysis
System .
Kennedy, M. P., and Tan, S. S. (2008). California Geological Survey, Regional Geologic Map No.
3, 1: 100,000 scale .
Sahakian, V ., et al. (2017). Seismic Constraints on the Architecture of the Newport-Inglewood/Rose
Canyon Fault: Implications for the Length and Magnitude of Future Earthquake Ruptures. American
Geophysical Union. DOI: 10.1002/2016JBO 13467.
Sampo Engineering Inc. (2018). Topographic Plat: 570-580 Laguna Drive, Carlsbad, California,
Scale 1" = 20' .
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COAST GEOTECHNICAL
REFERENCES (CONT.)
Brett Farrow
w.o. 686218
Page 28 of28
Seed, H.B., and Whitman, R.V. (1970). Design of earth retaining structures for dynamic loads.
In Proceedings of the ASCE Special Conference on Lateral Stresses, Ground Displacement and Earth
Retaining Structure, Ithaca, N.Y., pp. 103-147 .
Tan, S. S., and Giffen, D. G. (1995). Landslide Hazards in the Northern Part of the San Diego
Metropolitan Area, San Diego County, California, OFR 95-04, Plate 35D .
11111 Treiman, J. A. (1984). The Rose Canyon Fault Zone: A Review and Analysis, California Division
.. of Mines and Geology, Fault Evaluation Report 216 . ...
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Wood, J.H. (1973). Earthquake-induced soil pressures on structures. Ph.D. thesis, the California
Institute of Technology, Pasadena, Calififomia.
USGS, U.S. Seismic Design Maps, Scale= Variable.
https://earthquake.usgs.gov/designmaps/us/application.php
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APPENDIX A
COASTGEOTECHNICAL
5931 Sea Lion Place, Suite 109
Carlsbad, CA 92010
570-580 Laguna Drive
Carlsbad, CA 92008 Figure 1
P-686218 ·
-t;
~ -C 0 :.:; n, > Q) w
60
40
20
0
A
Top of Slope
@39.2'
A'
z
0 i= ~ Cl)
!
Q z w Ill
Cross Section A -A"
570-580 Laguna Dr.
Carlsbad, CA 92010
r-----------7
I I
I Proposed Apartment Units I
I I
I I
I .Qs I Existina Grade
a: Q
<( z :::>
Sidewalk 5 i;~~~.
: .-_ ..... :·.:_. ·._: .'·:. :· -:.=-:
A"
-12 c ·.-;-::. :_ :Z >:-::.:,.:• · :_ ._: :-.: ·.-:-:.-.-,;.·. :_ ·.;;·.•:·:.-.-,._..: ·.;;·.-:•::.-,._.. ·:.J ·.-: . .-.-_.,._..: ·.;;;;,;;.•:•:.-.-._..: ·.::.;;;.·.-:-::.-,._.. ~:~;. 1~._.. -~:•·.· ...... ·:.;..;..;;.:.· ....... _..: ·.· .·.• ·.·.·. · .. _. .. · ....... .-.·.-.... · ... ·.·,;,,;;;,;.-.. ·.· .· ....... ,._..: ·.· .· ... ·.-. .-.·.-.. .. . .. . •.. : ·.· .......• ·.· .. · ... • .·,
COASTGEOTECHNICAL
5931 Sea Lion Place, Suite 109
Carlsbad, CA 92010
CJC:11 0 10 20
Legend
--Certain Contact
·?--'!-
,. -,
I I
L -.I
bd
Uncertain Contact
Proposed Structure
Boring Location
40
Feet
60
Geologic Units ---
PJ:J.r.'7 Old Paralic Deposits ~
E~r#J Santiago Formation
80
Figure 3
W.O. P-686218
LOG OF EXPLORATORY BORING NO. 1
DRILL RIG: TRUCK-MOUNTED HOLLOW-STEM AUGER
BORING DIAMETER: 8.0"
PROJECT NO. P-686218
DATE DRILLED: 03-16-18
LOGGED BY: AG SURFACE ELEV.: 42.5' (Approximate)
~
~ ~ l ~ f-; ~ z w 6 ;;;-C ...... "'" '-' w r/J P:::: ...... u 8 f-; 0 w f-; r/J 6 0 0... --< 2, >-N 0 f-; > f-; u 0 w 0 czi ...... s ,-1 r/J ~ z ,-1 r/J z 0 0 J.r.l u --< ~ w --~ ,-1
f-; 25 u ,-1 ::r: u
>-r/J r/J ~ ~ f-; ~ d ...... r/J 0... P:::: 0 <l'. 0 w 0 0 ::;E ,-1 --< 0 0 0... p::) r/J r/J
GEOLOGIC DESCRIPTION
SM SOIL(Qs) Reddish Dk. Bm. fine grained sand, silty, organi cs
SP PARALIC DEPOSITS (Qop): Reddish bm., fine and med.-grained san
11 7.0 2.6
SPT 23.0 40
109.7 2.2
SPT 11 .5 34
Light red fine and coarse-grained sand, slightly moist pebbles
I 10.0 6.5
SPT 14.9 50 White to gray-light orange fine and coarse-grained sand
Gravel-Pebble layer
122.1 8.9 SC SANTIAGO FORMATION (Tsa) Gray-Pale Green clayey sandstone SPT 27.0 50
SPT 50
11 8.6 9.2
SPT 26.5 50
Fine and coarse-grained clayey sandstone is dense ro very dens
Distrube 8.3
SPT 25.2 50
End of Boring @ 50'. No Groundwater
SPT 50 Some caving due to auger removal
Backfilled with hydrated bentonite
SPT 27.2 50
SHEET 1 OF 1 COAST GEOTECHNICAL Figure
LOG OF EXPLORATORY BORING NO. 2
DRILL RIG: TRUCK-MOUNTED HOLLOW-STEM AUGER
BORING DIAMETER: 8.0"
PROJECT NO. P-686218
DATE DRILLED: 03-16-18
LOGGED BY: AG SURFACE ELEV.: 43.3' (Approximate)
~
~ e :::R 0 ~ ~
f-< ,...; 5 C z gJ µ..
C) µ-1 C/l ~ ......
8 f-< 0 µ-1 f-< 5 0 p.. ~ >--N
f-< u 0 f-< µ-1 >-< § C/l ~ z ,-..1 z 0 0 µ-1
µ-1 µ-1 --25 u ::r: 0 f-< ,-..1
>--C/l C/l ~ ~ f-< >-< C/l p.. ~ 0 ~ 0 µ-1 0 :::E ,-..1 -< 0 p::i C/l
126.4 8.5
SPT 27.8 22
104.2 6.5
SPT 12.8 34
Sample Distrube
SPT 11.6 43
106.6 6.7
SPT 24.4 50
SPT 50
SPT 24.4 50
SHEET 1 OF 1
0 0 ,-..1 u trl p..
~ 0
~ u
C/l e,
c/2 C/l -< ,-..1 u
d 0 C/l
GEOLOGIC DESCRIPTION
SM SOIL(Qs): Reddish Dk. Bm. fine grained sand, silty, organics
SP PARALIC DEPOSITS (Qop): Reddish bm., fine and med.-grained san
Light red fine and coarse-grained sand, slightly moist pebbles
White to gray-light orange fine and coarse-grained sand
Gravel-Pebble layer
SC SANTIAGO FORMATION (Tsa) Gray-Pale Green clayey sandstone
Fine and coarse-grained clayey sandstone is dense ro very dens
End of Boring @ 30'. No Groundwater
Some caving due to auger removal
Backfilled with hydrated bentonite
COAST GEOTECHNICAL Figure 5
CALIFORNIA FAULT MAP
Farrow
1100 -.-----------------------------,
1000
900
800
700
600
500
400
300
200
100
0
-1 00 -1---'--'"-'-+--'-.......... ~ ......... _.__.'--+-..._._ .......... .........,.._.__.........,~L...L--'-+....._.___.___.L.f--'.___._.L....1,_+-'-....._.,--'--t__,__..__._.l-i
-400 -300 -200 -100 0 100 200 300 400 500 600
Figure 6
NOTES:
(a)
IE-ENTRANT CORNER IIEINFORCEMENT
N0.38AASPlACEO
MID-HEIGHT IN SLAB
ISOLATION JOINTS
CONTRACTION JO'NTS
(c)
(b)
RE-ENTRANT CORNER CRAC.-:
1. Isolation joints around the columns should be either circular as shown in (a) or diamond shaped as shown in (b).
If no isolation joints are used around columns, or if the corners of the isolation joints do not meet the contraction joints,
radial cracking as shown in (c) may occur (reference ACI).
2. In order to control cracking at the re-entrant corners(+ /-270 degree corners), provide reinforcement as shown in (c).
3. Re-entrant corner reinforcement shown herein is provided as a general guideline only and is subject to verification and
changes by the project architect and / or structural engineer based upon slab geometry, location, and other
engineering and construction factors.
TYPICAL ISOLATION JOINTS AND
COAST GEOTECHNICAL RE-ENTRANT CORNER
Consulting Engineers & Geologists REINFORCEMENT
5931 Sea Lion Place, Suite 109 w.o. 686218 PLATE A Carlsbad, California 92010
858-755-8622
..... ___ -. 4
•
sat SVBGRAD£
NO. 8 ACCR£'0A TES
IN OPENINGS PER
IIANUF'ACMER SPECS.
P£'RIIEABt.EPAOS
(TRAFFIC RA 1£D)
OPEN GRADED
BASE (Ho. 57
STONE.-J/4'" IIAX.)
UPPER 12• AT 951' COIIPACTION.
(ASTII Dt551)
SGhematlc And Conceptual Only
No-Scale
TYPICAL llllftlHl■AIILll PAYIIR Dl!TAIL
J-t/B• 1HCK CONCRETE PA~
TRAFFIC LOADING
6. CONCR£1E
EDGf RESTRAIN
• B£DOING COURSE (NO. 8 AGGRE'CA Tf
M PER MANUFACTURER SPfCS)
.i
le
• 1HIO< 0P£N GRADED BASE. MITH
AIIN. s• PER HOOR INRL 11lA 110N RA 7f
(No. 57 SroNE -J/4• IIAX.)
-----31<t• GRAVEL
4• P(RFCJRA 1ED UNDERDRAIN
SCH. 40 PVC. ·
CONNECT TO PERF'ORA TED PIPES
. UNDER THE 8'0RETEN110N ARf'AS.
Plate B
APPENDIXB
LABORATORY TESTING AND RESULTS
Earth materials encountered in the exploratory trenches were closely examined and sampled for
laboratory testing. The laboratory tests were performed in accordance with the generally accepted
American Society for Testing and Materials (ASTM) test methods or suggested procedures.
Classification: The field classification was verified through laboratory examination, in accordance
with the Unified Soil Classification System. The final classification is shown on the enclosed
Exploratory Logs provided in Appendix B.
Grain Size Distribution: The grain size distribution of selected soil samples was determined in
accordance with ASTM D6913-04. The test result is presented on Table 4 and is graphically
depicted on the following pages.
TABLE4
Sieve Size 1" ¾" ½" #4 # 10 #20 #40 # 100 #200
Location Soil Type Percentage Passing
B1@5' 1 100 100 100 100 99.9 98.8 86.3 39.9 28.4
Expansion Index Test: An Expansion Test was performed on the selected sample. The test
procedure were conducted in accordance with the Uniform Building Code, Standard No. 29-2 and
AMST D-4829. The classification of expansive soil, based on the expansion index, are as indicated
in Table 29-C of the Uniform Building Code. The test result is presented on Table 5.
TABLES
Location Soil Expansion Degree of Uncorrected Corrected EI for
Type Reading Saturation Expansion Index (El) 50% Saturation
Bl @ 1-5' 1 -0.01 38.6 Sm NIA NIA
Maximum Dry Density and Optimum Moisture Content: The maximum dry density and optimum
moisture content were determined for selected samples of earth materials taken from the site. The
laboratory standard tests were in accordance with ASTM D-1557-12. The test result is presented on
Table 6.
TABLE6
Location Soil Type
Maximum Dry Optimum Moisture
Density (ym-pcf) Content (roopt-%)
Bl @ 1'-5' 1 130.0 9.0
Moisture/Density: The field moisture content and dry unit weight were determined for each of the
undisturbed soil samples. Test procedures were conducted in accordance with ASTM D7263-09
(Method A). This information is useful in providing a gross picture of the soil consistency or
variation among exploratory excavation. The field moisture content was determined as a percentage
of the dry unit weight. The dry unit weight was determined in pounds per cubic foot (pct). The test
results are presented on Table 7.
TABLE7
Field Field Dry Max. Dry Degree of
Sample Soil In-place Relative
Moisture Density Density Saturation
Location Type Compaction (%)
Content(%) (yd-pct) (ym-pct) (%)
1@3.5' 1 2.6 117.0 130 90.0 15.3
1@9' 2 2.2 109.7 130 84.4 10.7
1@14' 2 6.5 110.0 130 84.6 31.9
1@19' 3 8.9 122.1 ---
1@30' 3 9.2 118.6 ---
1@39' 3 8.3 88.1 ---
2@4' 1 8.5 126.4 130 97.2 65.2
2@9' 2 6.5 104.2 130 80.2 27.6
2@19' 3 6.7 106.6 ---
Shear Test: Shear tests were performed in a strain-control type direct shear machine. The laboratory
standard tests were in accordance with ASTM D3080. The rate of deformation was approximately
0.025 inches per minute. Each sample was sheared under varying confining loads in order to
determine the Coulomb shear strength parameters, cohesion, and angle of internal friction. Samples
were tested in a saturated condition. The test results are presented in Table 8.
TABLES
Sample ID Angle of Internal Friction Apparent Cohesion
B-1 @ 9' (ring) 29 degrees 70psf
B-1 @ 30' (ring) 34 degrees 350 psf
Sulfate and Chloride Tests: A sulfate test was performed on a selected sample in accordance with
California Test Method (CTM) 417, and a chloride test was performed on a selected sample in
accordance with California Test Method (CTM) 422. The test results are presented on Tables 9 and
10.
TABLE9
Sample ID Sulfate Content (ppm) Sulfate Content(% by wgt)
B-1 @ 1-5' 48 0.005
TABLE 10
Sample ID Chloride Content (ppm) Chloride Content (% by wgt)
B-1 @ 1.5' 21 0.002
Infiltration Testing: Infiltration tests were performed in accordance to ASTM D3385-09. This test
method is useful for field measurement of the infiltration rate of soils. A stabilized infiltration rate
of 2.48 inches per hour was established. The results of our testing are graphically shown on Figure
7. The rates indicated above are actual rates measured in the field and do not include a safety factor.
An adequate safety factor as recommended by the project engineer should be incorporated.
6
~ 5 ..c ........
C :.::::.4
(JJ
+"" ttS a: 3
C
0
~ 2 -+""
~
E1
0
Double Ring lnfiltrometer
Plot of Test Data
t--~--+----, ---. ~
15 30 45 60 75 90 105 120 135
Elapsed Time (min)
FIGURE 7
Field Resistivity Test: A field resistivity test was performed on a selected sample in accordance with
California Test Method (CTM) 643. The field resistivity test gives an indication of the quantity of
soluble salts in the soil or water to obtain data estimating the service life of culverts. The test results
for pH and field resistivity are presented on Table 11.
TABLE 11
pH: 7.6
Water Added (ml) Resistivity (ohm-cm)
10 13000
5 7800
5 6700
5 5600
5 5500
5 5200
5 5500
5 5900
60 years to perforation of a 16 gauge metal culvert.
78 years to perforation of a 14 gauge metal culvert.
108 years to perforation of a 12 gauge metal culvert.
13 8 years to perforation of a 10 gauge metal culvert.
168 years to perforation of a 8 gauge metal culvert.
SMS Geotechnical Solutions, Inc.
5931 Sea Lion place, Suite 109
Carlsbad, CA 92010
Project
Supervising Lab Tech
Farrow
Sieve Analysis
ASTM D 6913 -04
Sample 1
Job#
SB Sample
686218
Bl @ 1-5' I Soil type 1
Supervising Lab Manager MS Date I .....-===========--~=======----!:=====:::::::;
....---======: Tech WB
Address 578 Laguna Drive
Sample Wet Wt. 584.6 gr I Sample Dry Wt. ..__ __ s_6_3._s ___ g_r_.l Moisture% 3.7 %
Specification
Seive Accum. Wt. (gr) % Retained % Passing
D.G. Class 2
152mm 6"
75 mm 3"
50mm 2"
37.5 mm 11/2" 100 100
25 mm 1" 90-100 100
19mm 3/4" 87-100
12.5 mm 1/2"
9.5 mm 3/8"
4.75 mm #4 0.1 0.0 100.0 50-100 30-65
2 mm #10 0.8 0.1 99.9
0.85 mm #20 6.6 1.0 98.8
0.6 mm #30 25-55 5-35
0.425 mm #40 77.4 12.6 86.3
0.15 mm #100 338.4 46.3 39.9
0.075 mm #200 403.6 11.6 28.4 5-18 0-12 .
Pan 409.5 1.0
SMS Geotechnical Solutions, Inc.
5931 Sea Lion place, Suite 109
Carlsbad, CA 92010
Project
Supervising Lab Tech
Supervising Lab Manager
00 C: "iii
VI ro a.. ...,
C:
Cl) u ...
Cl) a..
100
90
80
70
60
so
40
30
20
10
0
500
i--J U) rl
Cobbles
m
100
Bl@ 1-5'
D60
D30
Dl0
Location Depth Symbol
Farrow
i--J ....... ~ i--J rl
~ ....... rl rr. rl
50
Gravel
Coarse I
D60
D30
DlO
uses
00 .......... M
10
Fine
Sieve Analysis
ASTM D 6913 -04
686218 Job# L---===========~ Address 578 Laguna Drive _.!::::::===::;-----;;:::::=====~
'¢
#
0 .-i
#
Date
0 N
#
5 1
Grain Size (mm)
0.5
Sand
Coarse I Medium l
D60
D30
D10
Fine
Tech
0 0 N
#
,-
l--1--+--------1
0.1 0.05 0.01
Silt or Clay
D60
D30
Dl0
-·-
NAT,w¾ LL PL Pl Cu (D60/D10) Cc(D230/D60*D10)
4
-~ Design Maps Summary Report
User-Specified Input
Report Title Laguna
Fri March 2, 2018 22:32:56 UTC
ASCE 7-10 Standard Building Code Reference Document
(which utilizes USGS hazard data available In 2008)
Site Coordinates
Site Soll Classlftcatlon
33.16541°N, 117.352°W
Site Class D -"Stiff Soil"
Risk Category I/II/III
USGS-Provided Output
s. = 1.158 g
S1 = 0.444 g
SMS = 1.201 g
SM1 = 0.691 g
S05 = 0.800 g
501 = 0.461 g
For Information on how the SS and 51 values above have been calculated from probabilistic (risk-targeted) and
deterministic ground motions In the direction of maximum horizontal response, please return to the application and
select the "2009 NEHRP" building code reference document.
ol --Jl
Ill
l<i:I
I I 1
(JOI
o ·
(UI~
'l~
(I .~J
a .
1.113
MCl:R Response Spectrum
aoo -t------◄--+--+--+--+--+--+--+--+-~
!lCICJ ~:XI Q~ O.W Qlll UXJ l..!I '~ I ~O I.Ill .<XI
Per100, T (uc)
Des r;r1 Responiic Spectrum
a,~
0.63
Q .,,
~ l H~
a v
iJ ;,,
Cl Id
o.o,
ow +-----1,--------------+--+-~
(l(XJ azc HO o.w !Ul'.l 1.00 I 20 I 'il I W I IIJ :too
P«10d. r (tee)
For PG~, Tu CRs, and CR1 values, please view the detailed report.
Although this Information Is a product of the U.S. Geological Survey, we provide no warranty, expressed or Implied, as to the accuracy of
the data contained therein. This tool ls not a substitute for technk:111 subject-matter knowledge.
...
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..
11111
...
..
j ..
... ..
... .. .. ..
... .. .. .. .. ..
...
1111
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--
--·-------------, . ., ' ,.,, .. ·--------·------
■USGS Design Maps Detailed Report
ASCE 7-10 Standard (33.16541°N, 117.352°W)
Site Class D -"Stiff Soil", Risk Category I/II/III
Section 11.4.1 -Mapped Acceleration Parameters
Note: Ground motion values provided below are for the direction of maximum horizontal
spectral response acceleration. They have been converted from corresponding geometric
mean ground motions computed by the USGS by applying factors of 1.1 (to obtain S5) and
1.3 (to obtain 51). Maps in the 2010 ASCE-7 Standard are provided for Site Class B.
Adjustments for other Site Classes are made, as needed, in Section 11.4.3.
From Figure 22-1 c1J Ss = 1.158 g
From Figure 22-2 c21 S1 = 0.444 g
Section 11.4.2 -Site Class
The authority having jurisdiction (not the USGS), site-specific geotechnical data, and/or
the default has classified the site as Site Class D, based on the site soil properties in
accordance with Chapter 20 .
"nlble 20.3-1 Site Classification
Site Class
A. Hard Rock
B. Rock
C. Very dense soil and soft rock
D. Stiff Soll
E. Soft clay soil
F. Soils requiring site response
analysis In accordance with Section
21.1
-Vs NorNc11 Su
> 5,000 ft./S N/A N/A
2,500 to 5,000 ft/S N/A N/A
1,200 to 2,500 ft/S >50 >2,000 psf
600 to 1,200 ft/S 15 to 50 1,000 to 2,000 psf
<600 ft/s <15 <1,000 psf
Any profile with more than 10 ft of soil having the
characteristics:
• Plasticity index PI > 20,
• Moisture content w i!:: 40%, and
• Undrained shear strength Su < 500 psf
See Section 20.3.1
For SI: lft/s = 0.3048 m/s 11b/ft2 = 0.0479 kN/m2
, ___ ,.,.,,__,., ________ _ , ----·----,_,, .... ---,---· ..
C
C
C
C
C
C
C
C
C
C
C
C
Section 11.4.3 -Site Coefficients and Risk-Targeted Maximum Considered Earthquake(~
Spectral Response Acceleration Parameters
Table 11.4-1: Site Coefficient F.
Site Class Mapped MCE R Spectral Response Acceleration Parameter at Short Period
S5 ~ 0.25 S5 = 0.50 Ss = 0.75 Ss = 1.00 Ss ~ 1.25
A 0.8 0.8 0.8 0.8 0.8
B 1.0 1.0 1.0 1.0 1.0
C 1.2 1.2 1.1 1.0 1.0
D 1.6 1.4 1.2 1.1 1.0
E 2.5 1.7 1.2 0.9 0.9
F See Section 11.4.7 of ASCE 7
Note: Use straight-line Interpolation for intermediate values of S5
For Site Clau = D and S. = 1,158 g, F. = 1.037
Table 11.4-2: Site Coefficient Fv
Site Class Mapped MCE R Spectral Response Acceleration Parameter at 1-s Period
S1 ~ 0.10 S1 = 0.20 S1 = 0.30 S1 = 0.40 S1 ~ a.so
A 0.8 0.8 0.8 0.8 0.8
B 1.0 1.0 1.0 1.0 1.0
C 1.7 1.6 1.5 1.4 1.3
D 2.4 2.0 1.8 1.6 1.5
E 3.5 3.2 2.8 2.4 2.4
F See Section 11.4. 7 of ASCE 7
Note: Use straight-line Interpolation for Intermediate values of S1
For Site Clau = D and S1 = 0.444 g, Fv = 1,558
Equation (11.4-1): SMs = FaSs = 1.037 X 1.158 = 1.201 g
Equation (11.4-2): SMl = fvS1 = 1.556 X 0.444 = 0.691 g
C Section 11.4.4 -Design Spectral Acceleration Parameters
Equation (11.4-3): Sos = ¾ SMs = ¾ X 1.201 = 0.800 g
C Equation (11.4-4): S01 = ¾ SMl = ¾ X 0.691 = 0.461 g
( Section 11.4. 5 -Design Response Spectrum
C
C
C
C
C
C
C
From figure 22-12 c3i TL = 8 seconds
Figure 11.4-1: Design Response Spectrum
Sc,;-OJ.!00
Sp, .. Q.461
I
I
I I -r----------,----------1 I I
I I I
I
T<T0 : 80 = S.. (0.4 +0.8T/T1 )
T11 ,T,T1 :s.•s..
T, <TS TL :S,=Sa, /T
T >TL: 81 • '1 TJP
Ptr10d, T ( MC)
.. ..
C
C
C
C
C
C
C
C
C ..
1111
.. .. .. ..
• ..
C
Section 11.4.6 -Risk-Targeted Maximum Considered Earthquake (MCEJ Response Spectrum
The MCER Response Spectrum Is determined by multiplying the design response spectrum above by
5ws .. 1.201
s,., .. 0.591
I
'
1.5.
I I
-~----------◄----------'
...
,.
' ...
...
1111
""
·----~""· .. -
Section 11.8.3 -Additional Geotechnlcal Investigation Report Requirements for Seismic Design
Categories D through F
From figure 22-7 c4i PGA = 0.460
Equation (11.8-1): PGAM = FpGAPGA = 1.040 x 0.460 = 0.478 g
Table 11.8-1: Site Coefficient FPGA
Site Mapped MCE Geometric Mean Peak Ground Acceleration, PGA
Class
PGA :S PGA= PGA = PGA = PGA~
0.10 0.20 0.30 0.40 a.so
A 0.8 0.8 0.8 0.8 0.8
B 1.0 1.0 1.0 1.0 1.0
C 1.2 1.2 1.1 1.0 1.0
D 1.6 1.4 1.2 1.1 1.0
E 2.5 1.7 1.2 0.9 0.9
F See Section 11.4.7 of ASCE 7
Note: Use straight-line interpolation for intermediate values of PGA
For Site Clau = D and PGA = 0,460 g, Fpu = 1,040
'-a Section 21.2.1.1 -Method 1 (from Chapter 21 -Site-Specific Ground Motion Procedures for
Seismic Design)
From Figure 22-12 csi CRS = 0.940
C From Figure 22-11 c•i CRl = 0.991
,,,.
L
.. .. .. --.. ..
1111 .. ..
...
1111
... .. .. .. -1111 -1111 .. .. ..
,.
Section 11.6 -Seismic Design Category
ble 11.6-1 Seismic Design cateaorv Based on Short Period Response Acceleration Parameter
RISK CATEGORY
VALUE OFSDS
I or II III IV
SDS < 0.167g A A A
0.167g S Sm< 0.33g B B C
o.33g s Sos < o.sog C C D
O.SOg S Sus D D D
For Risk category = I and s.,. = 0,800 g, Seismic Design Category = D
Tab le 11.6-2 Seismic Design Cateaory Based on 1-s d ti p et Perio Response Acee era on aram er
RISK CATEGORY
VALUE OFSD1
I orll Ill IV
~1 < 0.067g A A A
0.067g S SD1 < 0.133g B B C
0.133g S ~1 < 0.20g C C D
0.20g s SD1 D D D
For Rl•k category = I and S.,1 = 0.461 g, Seismic Design category = D
Note: When S1 is greater than or equal to 0.75g, the Seismic Design Category is E for
buildings in Risk Categories I, II, and III, and F for those in Risk Category IV, irrespective
of the above.
Seismic Design Category = "the more severe design category in accordance with
Table 11.6-1 or 11.6-2" = D
Note: See Section 11.6 for alternative approaches to calculating Seismic Design Category.
References
~ 1. Figure 22-1: https://earthquake.usgs.gov/hazards/deslgnmaps/downloads/pdfs/2010_ASCE-7 _Figure_22-1.pdf
2. Figure 22-2: https ://earthquake.usgs.gov /hazards/deslgnmaps/downloads/pdfs/2010_ASCE-7 _Figure_22-2.pdf
,. 3. Figure 22-12: https://earthquake.usgs.gov/hazards/deslgnmaps/downloads/pdfs/2010_.ASCE-
IIII 7_Figure_22-12.pdf
4. Figure 22-7: https ://earthquake .usgs.gov /hazards/designmaps/downloads/pdfs/2010_ASCE-7 _Flgure_22-7. pdf
• 5. Figure 22-17: https://earthquake.usgs.gov/hazards/deslgnmaps/downloads/pdfs/2010_ASCE-
._ 7_Flgure_22-17.pdf
6. Figure 22-18: https://earthquake.usgs.gov/hazards/deslgnmaps/downloads/pdfs/2010_.ASCE-
... 7_Flgure_22-18.pdf ..
...
' ..
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APPENDIXC
LAGOON P-686218
C:\STEDWIN\P-686218.PL2 Run By: MBNS 4/3/2018 6:09PM
140 .----,
120
100
80
60
40
20
# FS
a 1.5
b 1.5
Soil Soil Total : Saturated Cohesion Friction Piez.
Desc. Type Unit Wt. Unit Wt. Intercept Angle Surface
No. (pcf) : (pcf) (psf) (deg} No.
Qop 1 116.0: 122.0 70.0 29.0 : 0
Tsa 2 120.0: 128.0 350.0 34.0 : 0 -. . . . ] . . ....
' ' ' ···········-· ·r ···················: t · 1 ··· r
. . . . . . . . ' . ' . ' '
I 1 . I ~ 1 : I ·r . · .
: :6 J : 7 ; • 8, : 9
-------------·---·---------------·----~---------·---·-~-----------1 -------------~-----------------1.: _______________ • ___ :------------·------------------------
· +··· · 1······· I ] . i 1
. ' ' -------------------------------------,--------------------------------------.-----------------------------------------------------------.-------------------------------' ' ' ' ' . ' . . ' ' ' . ' ' . . ' . ' ' ' . ' . . . ' ' ' ' ' ' . ' . .
o ~---~--~-----'------'----~---~---~---~---~---~
0 20 40 60 80 100 120 140 160 180 200
GSTABL7 v.2 FSmin=1.5
--·-··-·-···--··-····--· .
GST.ABL7..
Safety Factors Are Calculated By The Modified Bishop Method
I STATIC ANALYSIS I
,,.. ..
1111 ..
.. ..
r ...
..
11111
... ...
1111 .. .. .. .. .. .. ..
... ...
C:\stedwin\p-686218.0UT Page 1
*** GSTABL7 ***
** GSTABL7 by Garry H. Gregory, P.E. **
** Original Version 1.0, January 1996; Current Version 2.0, September 2001 **
(All Rights Reserved-Unauthorized Use Prohibited)
*********************************************************************************
SLOPE STABILITY ANALYSIS SYSTEM
Modified Bishop, Simplified Janbu, or GLE Method of Slices.
(Includes Spencer & Morgenstern-Price Type Analysis)
Including Pier/Pile, Reinforcement, Soil Nail, Tieback,
Nonlinear Undrained Shear Strength, Curved Phi Envelope,
Anisotropic Soil, Fiber-Reinforced Soil, Boundary Loads, Water
Surfaces, Pseudo-Static Earthquake, and Applied Force Options.
*********************************************************************************
Analysis Run Date: 4/3/2018
Time of Run: 6:09PM
Run By: MB/VS
Input Data Filename: C:p-686218.
Output Filename: C:p-686218.0UT
Unit System: English
Plotted Output Filename: C:p-686218.PLT
PROBLEM DESCRIPTION: LAGOON P-686218
BOUNDARY COORDINATES
9 Top Boundaries
9 Total Boundaries
Boundary X-Left Y-Left X-Right Y-Right Soil Type
No. (ft) (ft) (ft) (ft) Below Bnd
1 0.00 25.00 5.00 25.00 2
2 5.00 25.00 11.00 30.00 2
3 11.00 30.00 27.00 40.00 2
4 27.00 40.00 40.00 50.00 1
5 40.00 50.00 57.00 60.00 1
6 57.00 60.00 70.00 62.00 1
7 70.00 62.00 100.00 63.00 1
8 100.00 63.00 136.00 63.00 1
9 136.00 63.00 182.00 64.00 1
ISOTROPIC SOIL PARAMETERS
2 Type(s) of Soil
Soil Total Saturated
Type Unit Wt. Unit Wt.
Cohesion
Intercept
(psf)
70.0
350.0
Friction Pore Pressure Piez.
Angle Pressure Constant surface
No. (pcf) (pcf) (deg) Param. (psf)
1 116.0 122.0 29.0 0.00 o.o
2 120.0 128.0 34.0 0.00 0.0
A Critical Failure Surface Searching Method, Using A Random
Technique For Generating Circular Surfaces, Has Been Specified.
1250 Trial Surfaces Have Been Generated.
25 Surfaces Initiate From Each Of 50 Points Equally Spaced
Along The Ground Surface Between X = 28.00(ft)
and X 45.00(ft)
Each surface Terminates Between X = 70.00(ft)
and X 110.00(ft)
Unless Further Limitations Were Imposed, The Minimum Elevation
At Which A Surface Extends Is Y = O.OO(ft)
5.00(ft) Line Segments Define Each Trial Failure Surface .
Following Are Displayed The Ten Most Critical Of The Trial
Failure Surfaces Evaluated. They Are
Ordered -Most Critical First .
No.
0
0
**Safety Factors Are Calculated By The Modified Bishop Method**
Total Number of Trial Surfaces Evaluated= 1250
Statistical Data On All Valid FS Values:
FS Max= 8.025 FS Min= 1.513 FS Ave= 3.582
Standard Deviation= 1.278 Coefficient of Variation 35.68 %
Failure Surface Specified By 11 Coordinate Points
Point x-surf Y-Surf
No. (ft) (ft)
1 29.39 41.84
2 34.14 43.38
... .. ..
..
C
C
C
.. ...
.. ..
C
Slice
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
C:\stedwin\p-686218.OUT Page 2
3 38.85 45.08
4 43.49 46.94
5 48.06 48.96
6 52.56 51.13
7 56.99 53.46
8 61.34 55.93
9 65.60 58.54
10 69.77 61.30
11 70.78 62.03
Circle Center At X = -13.8; Y = 183.0 and Radius, 147.6
Factor of Safety
*** 1.513 ***
Individual data on the 13 slices
Water Water Tie Tie Earthquake
Force Force Force Force Force Surcharge
Width Weight Top Bot Norm Tan Hor
(ft) (lbs) (lbs) (lbs) (lbs) (lbs) (lbs)
4.8 583.6 a.a 0.0 a.a 0.0 0.0
4.7 1675.3 0.0 0.0 0.0 a.a 0.0
1.2 568.1 o.o o.o 0.0 0.0 o.o
3.5 1932.8 a.a 0.0 0.0 0.0 o.o
4.6 2888.5 0.0 0.0 0.0 0.0 0.0
4.5 3144.6 o.o a.a a.a 0.0 0.0
4.4 3286.6 a.a 0.0 a.a 0.0 0.0
0.0 5.6 0.0 0.0 a.a 0.0 0.0
4.3 2839.0 0.0 0.0 a.a a.a 0.0
4.3 1858.1 a.a 0.0 0.0 0.0 0.0
4.2 831.7 0.0 a.a a.a 0.0 0.0
0.2 16.0 0.0 0.0 0.0 0.0 0.0
0.8 24.2 0.0 o.o 0.0 0.0 0.0
Failure surface Specified By 11 Coordinate Points
Point x-surf Y-Surf
No. (ft) (ft)
1 28.00 40. 77
2 32.68 42.52
3 37.33 44.38
4 41.93 46.33
5 46. 49 48.38
6 51. 00 50.54
7 55.47 52.78
8 59.88 55.13
9 64.25 57.57
10 68.56 60.10
11 71. 73 62.06
Circle Center At X = -50.8 i y = 258.3 and Radius,
Factor of Safety
*** 1.520 ***
Failure Surface Specified By 12 Coordinate Points
Point X-Surf Y-Surf
No. (ft) (ft)
1 28.69 41.30
2 33.66 41.88
3 38.57 42.81
4 43.41 44.07
5 48.15 45.67
6 52.77 47.59
7 57.24 49.83
8 61.54 52.37
9 65.66 55.21
10 69.57 58.33
11 73.25 61.71
12 73.64 62.12
Circle Center At X = 22.9; Y = 112.8 and Radius,
Factor of Safety
*** 1.521 ***
Failure Surface Specified By 11 Coordinate Points
Ver Load
(lbs) (lbs) o.o a.a o.o
0.0
0.0
0.0 a.a
0.0
0.0 a.a
0.0
0.0
0.0
231.4
71. 7
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
... .. ..
... ..
...
1111
... ..
...
.. ...
... .. ... .. ... .. .. .. ..
... .. .. ..
... .. .. ...
,,.
Ill
..
______________________ ., ·-----~-----
C:\stedwin\p-686218.OUT Page 3
Point
No.
1
2
3
4
5
6
7
8
9
10
11
Circle
X-Surf Y-Surf
(ft) (ft)
28.69 41.30
33.69 41.32
38.67 41.83
43.57 42.83
48.34 44.31
52.95 46.26
57.34 48.66
61.46 51.48
65.29 54.69
68.79 58.27
71.81 62.06
Center At X = 31.0; Y =
Factor of Safety
*** 1.525 ***
91.6 and Radius,
Failure Surface Specified By 11 Coordinate Points
Point X-Surf Y-Surf
No. (ft) (ft)
1 28.69 41.30
2 33.46 42.82
3 38.17 44.48
4 42.84 46.28
5 47.45 48.22
6 52.00 50.29
7 56.49 52.49
8 60.91 54.82
9 65.27 57.28
10 69.54 59.87
11 72.99 62.10
Circle Center At X --20.6; Y = 204.1 and Radius,
Factor of Safety
*** 1.535 ***
Failure Surface Specified By 11 Coordinate Points
Point x-surf Y-Surf
No. (ft) (ft)
1 29.39 41.84
2 34.39 41.74
3 39.37 42.18
4 44.27 43.15
5 49.05 44.64
6 53.63 46.63
7 57.98 49.09
8 62.04 52.01
9 65.77 55.35
10 69.11 59.06
11 71.27 62.04
50.4
170.1
Circle Center At X = 32.8; Y = 88.4 and Radius, 46.7
Factor of Safety
*** 1.548 ***
Failure Surface Specified By 11 Coordinate Points
Point x-surf Y-Surf
No. (ft) (ft)
1 28.69 41.30
2 33.39 43.02
3 38.05 44.83
4 42.67 46.75
5 47.25 48.76
6 51.78 50.88
7 56.26 53.09
8 60.70. 55.40
9 65.08 57.80
10 69.41 60.30
11 72.35 62.08
Circle Center At X = -48.1; Y = 259.0 and Radiu~, 230.8
Factor of Safety
.. .. .. .. ..
,. .. ..
1111
,. .. .. .. .. ..
1111 .. .. .. .. ...
C
C
C:\stedwin\p-686218.0UT Page 4
*** 1. 548 ***
Failure Surface Specified By 12 Coordinate Points
Point X-Surf Y-Surf
No. (ft) (ft)
1 28.35 41.04
2 33.34 41.29
3 38.30 41.93
4 43.19 42.96
5 47.99 44.35
6 52.67 46.12
7 57.20 48.24
8 61.55 50.71
9 65.69 53.51
10 69.61 56.61
11 73.28 60.01
12 75.27 62.18
Circle Center At X = 27.6; Y 105.3 and Radius, 64.3
Factor of Safety
*** 1.567 ***
Failure Surface Specified By 11 Coordinate Points
Point X-Surf Y-Surf
No. (ft) (ft)
1 28.00 40.77
2 32.59 42.75
3 37.16 44.77
4 41.72 46.84
5 46.25 48.95
6 50.76 51.10
7 55.26 53.29
8 59.73 55.53
9 64.18 57.80
10 68.61 60.12
11 72.28 62.08
Circle Center At X = -183.0; Y = 536.1 and Radius, 538.4
Factor of Safety
*** 1.582 ***
Failure Surface Specified By 12 Coordinate Points
Point X-Surf Y-Surf
No. (ft) (ft)
1 29.04 41.57
2 34.04 41.35
3 39.03 41.63
4 43.97 42.42
5 48.80 43.70
6 53.48 45.47
7 57.95 47.70
8 62.18 50.37
9 66.11 53.46
10 69.71 56.93
11 72.94 60.75
12 73.89 62.13
Circle Center At X = 33.8; Y = 90.4 and Radius, 49.1
Factor of Safety
*** 1.609 ***
**** END OF GSTABL7 OUTPUT****
LAGOON P-686218
C:\STEDWIN\P-686218.PL2 Run By: MBNS 4/3/2018 6:05PM
140 .-----.
120
100
80
60
40
20
# FS
a 1.1
b 1.1
Soil Soil Total : Saturated Cohesion Friction Piez. I Load : Value
Desc. Type Unit Wi. Unit Wt. Intercept Angle Surface Horiz Eqk 0.160 g<
No. (pcf) : (pcf) (psf) (deg) No.
Qop 1 116.0: 122.0 70.0 29.0 : 0
Tsa 2 120.0: 128.0 350.0 34.0 : 0
· · · bl : 7 ' 8 ' · 9
········•····•···1····················~····•··~··~···+···1 ·············r·········~·······1-i ................ ~ .. L .................. 1 .................... : ................. .
-................................................ ···················1··················· ··················· ................... ··················· ·················
. . I O I I -------------------------------------,----------------------------------------,-----------------------------------------------------------,---•-······-----------------------------,------------------• I I I . . . ' I t I I
I t I I
' ' ' ' ' . ' ' . ' . . ' ' . ' ' . ' ' ' ' ' ' ' ' ' '
0 '------'------'------'------'----~---~---~---~---~---~
0 20 40 60 80 100 120 140 160 180 200
GSTABL7 v.2 FSmin=1.1
Safety Factors Are Calculated By The Modified Bishop Method
GSTABL7.
PSEUDO-STATIC ANALYSIS
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11111
C:\stedwin\p-686218.0UT Page 1
*** GSTABL7 ***
** GSTABL7 by Garry H. Gregory, P.E. **
** Original Version 1.0, January 1996; Current Version 2.0, September 2001 **
(All Rights Reserved-Unauthorized Use Prohibited)
*********************************************************************************
SLOPE STABILITY ANALYSIS SYSTEM
Modified Bishop, Simplified Janbu, or GLE Method of Slices .
(Includes Spencer & Morgenstern-Price Type Analysis)
Including Pier/Pile, Reinforcement, Soil Nail, Tieback,
Nonlinear Undrained Shear Strength, curved Phi Envelope,
Anisotropic Soil, Fiber-Reinforced Soil, Boundary Loads, Water
Surfaces, Pseudo-Static Earthquake, and Applied Force Options .
*********************************************************************************
Analysis Run Date: 4/3/2018
Time of Run: 6:05PM
Run By: MB/VS
Input Data Filename: C:p-686218.
Output Filename: C:p-686218.0UT
Unit System: English
Plotted Output Filename: C:p-686218.PLT
PROBLEM DESCRIPTION: LAGOON P-686218
BOUNDARY COORDINATES
9 Top Boundaries
9 Total Boundaries
Boundary X-Left
No. (ft)
1 0.00
Y-Left
(ft)
25.00
25.00
30.00
40.00
50.00
60.00
62.00
63.00
63.00
X-Right
(ft)
5.00
11. 00
27.00
40.00
57.00
70.00
Y-Right
(ft)
25.00
30.00
40.00
50.00
60.00
62.00
63.00
63.00
64.00
Soil Type
Below Bnd
2
2 5.00
3 11. 00
4 27.00
5 40.00
6 57.00
7 70.00
8 100.00
9 136.00
ISOTROPIC SOIL PARAMETERS
2 Type(s) of Soil
100.00
136.00
182.00
Pore Soil Total Saturated Cohesion
Type Unit Wt. Unit Wt. Intercept
Friction
Angle
(deg)
29.0
34.0
Pressure
No. (pcf) (pcf) (psf)
1 116.0 122.0 70.0
2 120.0 128.0 350.0
A Horizontal Earthquake Loading Coefficient
Of0.160 Has Been Assigned
A Vertical Earthquake Loading Coefficient
Of0.000 Has Been Assigned
Cavitation Pressure= O.O(psf)
Param.
0.00
0.00
Pressure
Constant
(psf) o.o
0.0
2
2
1
1
1
1
1
1
Piez.
Surface
No.
0
0
A Critical Failure Surface Searching Method, Using A Random
Technique For Generating Circular Surfaces, Has Been Specified.
1250 Trial Surfaces Have Been Generated .
25 Surfaces Initiate From Each Of 50 Points Equally Spaced
Along The Ground Surface Between X = 28.00(ft)
and X 45.00(ft)
Each Surface Terminates Between X 70.00(ft)
and X = 110.00(ft)
Unless Further Limitations Were Imposed, The Minimum Elevation
At Which A Surface Extends Is Y = O.OO(ft)
5.00(ft) Line Segments Define Each Trial Failure surface.
Following Are Displayed The Ten Most Critical Of The Trial
Failure Surfaces Evaluated. They Are
Ordered -Most Critical First .
**Safety Factors Are Calculated By The Modified Bishop Method**
Total Number of Trial Surfaces Evaluated= 1250
Statistical Data On All Valid FS Values:
FS Max= 3.436 FS Min= 1,087 FS Ave= 2.097
Standard Deviation= 0.545 Coefficient of Variation= 25.99 %
.. --.. .. .. .. .. -.. .. -..
.. .. .. .. .. ..
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-..
Slice
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
C:\stedwin\p-686218.OUT Page 2
Failure surface Specified By 12
Point X-Surf Y-Surf
No .
1
2
3
4
5
6
7
8
9
10
11
12
(ft) (ft)
28.69 41.30
33.66 41.88
38.57 42.81
43.41 44.07
48.15 45.67
52.77 47.59
57.24 49.83
61.54 52.37
65.66 55.21
69.57 58.33
73.25 61.71
73.64 62.12
Circle Center At X = 22.9; Y
Factor of Safety
*** 1.087 ***
Coordinate Points
112.8 and Radius, 71.7
14 slices
Width
Individual data on the
Water Water
Force Force
Weight Top Bot
Tie Tie
Force
Norm
(lbs)
Force
Tan
surcharge
Earthquake
Force
Hor Ver Load
(ft)
5.0
4.9
1. 4
3.4
4.7
4.6
4.2
0.2
4.3
4.1
3.9
0.4
3.3
0.4
(lbs) (lbs) (lbs)
933.3 o.o o.o
2660.8 0.0 0.0
1067.9 0.0 0.0
2920.3 0.0 o.o
4688.9 0.0 0.0
5098.3 0.0 o.o
4962.5 0.0 0.0
281.2 0.0 0.0
4626.1 0.0 0.0
3448.9 0.0 0.0
2205.0 0.0 0.0
172.8 0.0 o.o
692.0 0.0 0.0
9.0 o.o o.o
o.o
0.0
0.0
0.0
0.0
0.0 o.o
0.0 o.o
0.0 o.o
0.0
0.0 o.o
(lbs)
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
(lbs)
149.3
425.7
170.9
467.3
750.2
815.7
794.0
45.0
740.2
551. 8
352.8
27.6
110.7
1. 4
Failure
Point
Surface Specified By 11 Coordinate Points
No.
1
2
3
4
5
6
7
8
9
10
11
X-Surf Y-Surf
(ft) (ft)
29.39 41.84
34.14 43.38
38.85 45.08
43.49 46.94
48.06 48.96
52.56 51.13
56.99 53.46
61.34 55.93
65.60 58.54
69.77 61.30
70.78 62.03
Circle Center At X = -13.8; Y -183.0 and Radius,
Factor of Safety
*** 1.090 ***
Failure Surface Specified By 11 Coordinate Points
Point x-surf Y-Surf
No. (ft) (ft)
1 28.00 40.77
2 32.68 42.52
3 37.33 44.38
4 41.93 46.33
5 46.49 48.38
6 51.00 50.54
7 55.47 52.78
8 59.88 55.13
9 64.25 57.57
(lbs) (lbs)
0.0 0.0
0.0 0.0 o.o 0.0
0.0 0.0 o.o 0.0 o.o 0.0
0.0 0.0
0.0 0.0
0.0 0.0 o.o o.o o.o 0.0
0.0 0.0 o.o 0.0
0.0 0.0
147.6
-.. .. ..
... ...
,,,.
11111
...
..
11111 ..
..
.. ..
...
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C:\stedwin\p-686218.0UT Page 3
10 68.56 60.10
11 71.73 62.06
Circle Center At X = -50.8; Y
Factor of Safety
258.3 and Radius, 231.4
*** 1.092 ***
Failure
Point
surface Specified By 11 Coordinate Points
No.
1
2
3
4
5
6
7
8
9
10
11
Circle
X-Surf Y-Surf
(ft) (ft)
28.69 41.30
33.46 42.82
38.17 44.48
42.84 46.28
47.45 48.22
52.00 50.29
56.49 52.49
60.91 54.82
65.27 57.28
69.54 59.87
72.99 62.10
Center At X = -20.6; Y
Factor of Safety
*** 1.094 ***
204.1 and Radius,
Failure
Point
Surface Specified By 11 Coordinate Points
No.
1
2
3
4
5
6
7
8
9
10
11
X-Surf Y-Surf
(ft) (ft)
28.69 41.30
33.69 41.32
38.67 41.83
43.57 42.83
48.34 44.31
52.95 46.26
57.34 48.66
61.46 51.48
65.29 54.69
68.79 58.27
71.81 62.06
Circle Center At X = 31.0; Y =
Factor of Safety
*** 1.105 ***
91.6 and Radius,
Failure surface Specified By 11 coordinate Points
Point X-Surf Y-Surf
No. (ft) (ft)
1 28.69 41.30
2 33.39 43.02
3 38.05 44.83
4 42.67 46.75
5 47.25 48.76
6 51.78 50.88
7 56.26 53.09
8 60.70 55.40
9 65.08 57.80
10 69.41 60.30
11 72.35 62.08
Circle Center At X = -48.1; Y = 259.0 and Radius,
Factor of Safety
*** 1.107 ***
Failure surface Specified By 12 Coordinate Points
Point x-surf Y-Surf
No. (ft) (ft)
1 28.35 41.04
2 33.34 41.29
3 38.30 41.93
4 43.19 42.96
5 47.99 44.35
6 52.67 46.12
7 57.20 48.24
170.1
50.4
230.8
-.. .. ...
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C:\stedwin\p-686218.OUT Page 4
8 61.55 50.71
9 65.69 53.51
10 69.61 56.61
11 73.28 60.01
12 75.27 62.18
Circle Center At X = 27.6; Y
Factor of Safety
*** 1.114 ***
Failure
Point
No.
1
2
3
4
5
6
7
8
9
10
11
Surface Specified By 11
X-Surf Y-Surf
(ft) (ft)
29.39 41.84
34.39 41.74
39.37 42.18
44.27 43.15
49.05 44.64
53.63 46.63
57.98 49.09
62.04 52.01
65.77 55.35
69.11 59.06
71.27 62.04
Circle Center At X = 32.8; Y
Factor of Safety
*** 1.122 ***
Failure Surface Specified By 11
Point X-Surf Y-Surf
No. (ft) (ft)
1 28.00 40.77
2 32.59 42.75
3 37.16 44.77
4 41.72 46.84
5 46.25 48.95
6 50.76 51.10
7 55.26 53.29
8 59.73 55.53
9 64.18 57.80
10 68.61 60.12
11 72.28 62.08
105.3 and Radius,
Coordinate Points
88.4 and Radius,
Coordinate Points
Circle Center At X = -183.0; Y =
Factor of Safety
536.1 and Radius,
*** 1.133 ***
Failure
Point
No .
1
2
3
4
5
6
7
8
9
10
11
Circle
Surface Specified By 11 Coordinate Points
X-Surf Y-Surf
(ft) (ft)
30.08 42.37
34.82 43.97
39.52 45.66
44.19 47.46
48.82 49.35
53.40 51.34
57.95 53.43
62.44 55.62
66.89 57.90
71.29 60.28
74.59 62.15
Center At X = -42.2; Y = 265.1 and Radius,
Factor of Safety
*** 1.149 ***
**** END OF GSTABL7 OUTPUT****
64.3
46.7
538.4
234.2
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APPENDIXD
.. -..
C
C
,..
L.
C
C
C
C
C
..
----· ~--------
Grading Guidelines
Grading should be performed to at least the minimum requirements of the local governing agencies,
the California Building Code, 2016, the geotechnical report and the guidelines presented below. All
of the guidelines may not apply to a specific site and additional recommendations may be necessary
during the grading phase.
Site Clearing
Trees, dense vegetation, and other deleterious materials should be removed from the site.
Non-organic debris or concrete may be placed in deeper fill areas under direction of the Soils
engmeer.
Subdrainage
• During grading, the Geologist and Soils Engineer should evaluate the necessity of placing
additional drains.
• All subdrainage systems should be observed by the Geologist and Soils Engineer during
construction and prior to covering with compacted fill.
• Consideration should be given to having subdrains located by the project surveyors. Outlets
should be located and protected.
Treatment of Existing Ground
• All heavy vegetation, rubbish and other deleterious materials should be disposed of off site.
• All surficial deposits including alluvium and colluvium should be removed unless otherwise
indicated in the text of this report. Groundwater existing in the alluvial areas may make
excavation difficult. Deeper removals than indicated in the text of the report may be
necessary due to saturation during winter months.
• Subsequent to removals, the natural ground should be processed to a depth of six inches,
moistened to near optimum moisture conditions and compacted to fill standards.
Fill Placement
• Most site soil and bedrock may be reused for compacted fill; however, some special
processing or handling may be required (see report). Highly organic or contaminated soil
should not be used for compacted fill.
• Material used in the compacting process should be evenly spread, moisture conditioned,
processed, and compacted in thin lifts not to exceed six inches in thickness to obtain a
uniformly dense layer. The fill should be placed and compacted on a horizontal plane, unless
otherwise found acceptable by the Soils Engineer.
• If the moisture content or relative density varies from that acceptable to the Soils engineer,
the Contractor should rework the fill until it is in accordance with the following:
• Moisture content of the fill should be at or above optimum moisture. Moisture should
be evenly distributed without wet and dry pockets. Pre-watering of cut or removal areas
should be considered in addition to watering during fill placement, particularly in clay
or dry surficial soils .
... .. .. .. .. ..
.. .. .. ..
C
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11111 .. .. .. ..
• Each six inch layer should be compacted to at least 90 percent of the maximum density
in compliance with the testing method specified by the controlling governmental agency .
In this case, the testing method is ASTM Test Designation D-1557-91.
• Side-hill fills should have a minimum equipment-width key at their toe excavated through
all surficial soil and into competent material (see report) and tilted back into the hill. As the
fill is elevated, it should be benched through surficial deposits and into competent bedrock
or other material deemed suitable by the Soils Engineer.
• Rock fragments less than six inches in diameter may be utilized in the fill, provided:
• They are not placed in concentrated pockets;
• There is a sufficient percentage of fine-grained material to surround the rocks;
• The distribution of the rocks is supervised by the Soils Engineer .
• Rocks greater than six inches in diameter should be taken off site, or placed in accordance
with the recommendations of the Soils Engineer in areas designated as suitable for rock
disposal .
• In clay soil large chunks or blocks are common; if in excess of six ( 6) inches minimum
dimension then they are considered as oversized. Sheepsfoot compactors or other suitable
methods should be used to break the up blocks.
• The Contractor should be required to obtain a minimum relative compaction of 90 percent
out to the finished slope face of fill slopes. This may be achieved by either overbuilding the
slope and cutting back to the compacted core, or by direct compaction of the slope face with
suitable equipment.
If fill slopes are built "at grade" using direct compaction methods then the slope construction
should be performed so that a constant gradient is maintained throughout construction. Soil
should not be "spilled" over the slope face nor should slopes be "pushed out" to obtain
grades. Compaction equipment should compact each lift along the immediate top of slope.
Slopes should be back rolled approximately every 4 feet vertically as the slope is built.
Density tests should be taken periodically during grading on the flat surface of the fill three
to five feet horizontally from the face of the slope .
In addition, if a method other than over building and cutting back to the compacted core is
to be employed, slope compaction testing during construction should include testing the outer
six inches to three feet in the slope face to determine if the required compaction is being
achieved. Finish grade testing of the slope should be performed after construction is
complete. Each day the Contractor should receive a copy of the Soils Engineer's "Daily Field
Engineering Report" which would indicate the results of field density tests that day .
• Fill over cut slopes should be constructed in the following manner:
• All surficial soils and weathered rock materials should be removed at the cut-fill
interface .
.. .. -.. .. .. -.. .. .. .. .. .. .. ..
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It ..
• A key at least 1 equipment width wide (see report) and tipped at least 1 foot into slope
should be excavated into competent materials and observed by the Soils Engineer or his
representative .
• The cut portion of the slope should be constructed prior to fill placement to evaluate if
stabilization is necessary, the contractor should be responsible for any additional
earthwork created by placing fill prior to cut excavation .
• Transition lots ( cut and fill) and lots above stabilization fills should be capped with a four
foot thick compacted fill blanket (or as indicated in the report).
• Cut pads should be observed by the Geologist to evaluate the need for overexcavation and
replacement with fill. This may be necessary to reduce water infiltration into highly
fractured bedrock or other permeable zones, and/or due to differing expansive potential of
materials beneath a structure. The overexcavation should be at least three feet. Deeper
overexcavation may be recommended in some cases .
• Exploratory backhoe or dozer trenches still remaining after site removal should be excavated
and filled with compacted fill if they can be located .
Grading Observation and Testing
• Observation of the fill placement should be provided by the Soils Engineer during the
progress of grading.
• In general, density tests would be made at intervals not exceeding two feet of fill height or
every 1,000 cubic yards of fill placed. This criteria will vary depending on soil conditions
and the size of the fill. In any event, an adequate number of field density tests should be
made to evaluate if the required compaction and moisture content is generally being
obtained.
• Density tests may be made on the surface material to receive fill, as required by the Soils
Engineer.
• Cleanouts, processed ground to receive fill, key excavations, subdrains and rock disposal
should be observed by the Soils Engineer prior to placing any fill. It will be the Contractor's
responsibility to notify the Soils Engineer when such areas are ready for observation.
• A Geologist should observe subdrain construction.
• A Geologist should observe benching prior to and during placement of fill.
Utility Trench Backfill
Utility trench backfill should be placed to the following standards:
•
•
•
Ninety percent of the laboratory standard if native material is used as backfill.
As an alternative, clean sand may be utilized and flooded into place. No specific relative
compaction would be required; however, observation, probing, and if deemed necessary,
testing may be required.
Exterior trenches, paralleling a footing and extending below a 1: 1 plane projected from the
outside bottom edge of the footing, should be compacted to 90 percent of the laboratory
standard. Sand backfill, unless it is similar to the inplace fill, should not be allowed in these
trench-backfill areas.
Density testing along with probing should be accomplished to verify the desired results .
APN:
lr/W
lr/W
BUENA v1STA
LAGOON
155-221-11
POR77ON
ADD ID'
STRITT DEDICA T/ON
PER ASSfSSOR PAGE
TOPOG
N89'24'49'W 25.22'
· AC PAVEMENT ··
·. . .
°'43.52 .
I ., . ,
.1
. I
I
. ·. ·_· r
;
. '
PHIC PLAT
LOT 1
MAP
~ H4J
FF@THR[SI-/OL!)
fX/SllNG
BUILDING
.• f---.\-43.24
43.68
·.,. 'i
ill !"":;
·_. f"'"' I
/] G
,V::i ~ I -_ . I
2942
APN· 155-227-15
APN· 755-221-14
APN· 155-221-IJ
SDG[ HH
RIM:45.55
FHg
~• 42-64 fl. ·. . ' ,· 4JD5 fl.~-j~~~,._-~:c_,. 4369 fl. • . , 44.19 FL• · · • ·44.48 FL',.;',. • 44.87 fl. R/W
CLIENT: BRffi FARROW
SITE ADDRESS: 570-580 LAGUNA DRIVE,
CARLSBAD, CA 92008
ASSESSOR'S PARCEL NO.: 155-221-12
LEGALDESCRIP'I10N: PORTION Of LOT/, SECT/ON /, TOWNSHIP 12 SOUTH,
RANGE 5 MST.
VERTICAL BENCHMARK: CITY Of CARLSBAD SURVEY CONTROL POINT I 39
PER RECORD Of SURVEY 17271
DA TUM· NGVD29 ELEVATION: 8222'
NOTES:
/. PROPERTY UNE BEARING AND DISTANCES SHOWN HEREON CALCULATED PER
RECORD DEED BEARINGS ARE SHOWN IN TERMS Of NAD83 COORDS
2 PRELIMINARY TITLE REPORT WAS NO PROI//DED BY THE CUENT.
ABBREVIATIONS:
AC: ASPHALT CONCRETE
AD: AREA DRAIN
BP: BACKFLOW PREVENTER
CO: CLEANOUT
CONC: CONCRETE £: ELECTRIC METER
EHH· ELECTRIC HAND HOLE
EP: EDGE OF PAVEMENT
FF: FINISH FLOOR
FG: FINISH GRADE
FH: FIR[ HYDRANT
FL-FLOW LINE
G: GAS METER GF: GARAGE FLOOR
HG.· HANDICAP
HH: HAND HOLE LP: LIGHT POST
IR~ IRRIGATION VALVE
PP: POWER POLE
R/W: RIGHT OF WAY
SDMH: STORM DRAIN MANHOLE
SL: STREET LIGHT
TC: TOP OF CURB
TG: TOP OF GRATE
W: WA TER METER
W WATER VALVE
LEGEND·
PROPERTY BOUNDARY
RIGHT-OF-WAY
EXIST/NG CONTOUR
EXIST/NG ELEVAT/ON
IND/CA TES ELEVA T/ON ABOVE GRADE
SYMBOL:
-150-
X 150.5
[160.0]
Geotechnical Legend
~ B-1
Approx. Borehole Locatlon
A A Geologic Cross-Section .. 4 -Approx. lnfiltration Test Location IF
(Qs) Top Soil
(Qop) Old Paralic
Deposit
(Tsa) Santiago Formation
Project No. 686218 Dated: 3/26/18
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