HomeMy WebLinkAboutSDP 2018-0020; 540 CHESTNUT AVE; GEOTECHNICAL INVESTIGATION PROPOSED RESIDENTIAL DEVELOPMENT 540 CHESTNUT AVENUE CARLSBAD, CA; 2020-02-25'5~
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CTEL~,,, Construction Testing & Engineering, Inc.
Inspection I leshng I Geotechnical I Environmental & Construction Engineering I Civil Engineering I Surveying
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GEOTECHNICAL INVESTIGATION _______ I0'2a
PROPOSED RESIDENTIAL DEVELOPM Initial Date
540 CHESTNUT AVENUE
CARLSBAD, CALIFORNIA
Prepared for:
BG CONSOLIDATED, LLC
C/O: DAVID CARRON
110 COPPERWOOD WAY SUITE P
OCEANSIDE, CALIFORNIA 92056
Prepared by:
CONSTRUCTION TESTING & ENGINEERING, INC.
1441 MONTIEL ROAD, SUITE 115
ESCONDIDO, CALIFORNIA 92026
kE CEIVED
MAR 18 ZOZO
LAND DEVELOPMENT
ENGINEERING
CTE JOB NO.: 10-13921S FEBRUARY 25, 2020
1441 Montiel Road, Suite 115 1 Escondido, CA 92026 1 Ph (760) 746-4955 1 Fax (760) 746-9806 1 www.cte-inc.net
TABLE OF CONTENTS
1.0 INTRODUCTION AND SCOPE OF SERVICES ...................................................................1
1.1 Introduction...................................................................................................................1
1.2 Scope of Services..........................................................................................................1
2.0 SITE DESCRIPTION...............................................................................................................1
3.0 FIELD INVESTIGATION AND LABORATORY TESTING................................................2
3.1 Field Investigation........................................................................................................2
3.2 Laboratory Testing........................................................................................................3
4.0 GEOLOGY...............................................................................................................................3
4.1 General Setting .............................................................................................................3
4.2 Geologic Conditions .....................................................................................................3
4.2.1 Quaternary Undocumented Fill .....................................................................4
4.2.2 Residual Soil..................................................................................................4
4.2.3 Quaternary Old Paralic Deposits ...................................................................4
4.3 Groundwater Conditions...............................................................................................5
4.4 Geologic Hazards..........................................................................................................5
4.4.1 Surface Fault Rupture....................................................................................5
4.4.2 Local and Regional Faulting..........................................................................6
4.4.3 Liquefaction and Seismic Settlement Evaluation..........................................7
4.4.4 Tsunamis and Seiche Evaluation...................................................................8
4.4.5 Landsliding ....................................................................................................8
4.4.6 Compressible and Expansive Soils................................................................8
4.4.7 Corrosive Soils...............................................................................................9
5.0 CONCLUSIONS AND RECOMMENDATIONS .................................................................10
5.1 General........................................................................................................................10
5.2 Site Preparation...........................................................................................................10
5.3 Site Excavation...........................................................................................................12
5.4 Fill Placement and Compaction..................................................................................12
5.5 Fill Materials...............................................................................................................12
5.6 Temporary Construction Slopes .................................................................................13
5.7 Foundations and Slab Recommendations...................................................................14
5.7.1 Foundations..................................................................................................14
5.7.2 Foundation Settlement ............. . ................................................................... 16
5.7.3 Foundation Setback......................................................................................16
5.7.4 Interior Concrete Slabs ................................................................................16
5.8 Seismic Design Criteria..............................................................................................17
5.9 Lateral Resistance and Earth Pressures ......................................................................18
5.10 Exterior Flatwork......................................................................................................20
5.11 Vehicular Pavement..................................................................................................21
5.12 Drainage....................................................................................................................22
5.13 Slopes........................................................................................................................22
5.14 Controlled Low Strength Materials (CLSM)............................................................23
5.15 Plan Review .............................................................................................................. 24
5.16 Construction Observation.........................................................................................24
6.0 LIMITATIONS OF INVESTIGATION.................................................................................25
I
FIGURES
FIGURE 1
FIGURE 2
FIGURE 3
FIGURE 4
SITE LOCATION MAP
GEOLOGIC/ EXPLORATION LOCATION MAP
REGIONAL FAULT AND SEISMICITY MAP
RETAINING WALL DRAINAGE DETAIL
APPENDICES
APPENDIX A
APPENDIX B
APPENDIX C
APPENDIX D
REFERENCES
FIELD EXPLORATION METHODS AND BORING LOGS
LABORATORY METHODS AND RESULTS
STANDARD GRADING SPECIFICATIONS
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1.0 INTRODUCTION AND SCOPE OF SERVICES
1.1 Introduction
Construction Testing and Engineering, Inc. (CTE) has completed a geotechnical investigation and
report providing conclusions and recommendations for the proposed improvements at the subject
site in Carlsbad, California. It is understood that the proposed improvements are to consist of three
single-story structures with associated flatwork, utilities, landscaping and other minor
improvements. CTE has performed this work in general accordance with the terms of proposal
034019S dated September 1, 2017. Preliminary geotechnical recommendations for excavations, fill
placement, and foundation design for the proposed improvements are presented herein.
1.2 Scope of Services
The scope of services provided included:
Review of readily available geologic and soils reports.
Coordination of USA mark-out and location.
Excavation of exploratory borings and soil sampling utilizing limited-access manually operated
drilling equipment
Laboratory testing of selected soil samples.
Description of the site geology and evaluation of potential geologic hazards.
Engineering and geologic analysis.
Preparation of this preliminary geotechnical report.
2.0 SITE DESCRIPTION
The subject site is located at 540 Chestnut Avenue in Carlsbad, California (Figure 1). The site is
bounded by Chestnut Avenue to the southeast, Tyler Street to the southwest, Roosevelt Street to the
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northeast, and a residence to the northwest. The site layout is illustrated on Figure 2. The
improvement area is currently an undeveloped lot with utilities. Based on reconnaissance and
review of topography, the improvement area gradually descends to the southwest with elevations
ranging from approximately 50 feet above mean sea level (msl) in the northeast to approximately 47
feet to the southwest.
3.0 FIELD INVESTIGATION AND LABORATORY TESTING
3.1 Field Investigation
CTE performed the subsurface investigation on January 16, 2020 to evaluate underlying soil
conditions. This fieldwork consisted of a site reconnaissance, and the excavation of two exploratory
soil borings in representative areas. The borings were advanced with a limited-access manually
operated auger that extended to a maximum explored depth of approximately 10.0 feet below ground
surface (bgs). Bulk samples were collected from the cuttings. Approximate locations of the soil
borings are shown on the attached Figure 2.
Soils were logged in the field by a CTE Engineering Geologist, and were visually classified in
general accordance with the Unified Soil Classification System. The field descriptions have been
modified, where appropriate, to reflect laboratory test results. Boring logs, including descriptions of
the soils encountered, are included in Appendix B. The approximate locations of the borings are
presented on Figure 2.
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3.2 Laboratory Testing
Laboratory tests were conducted on selected soil samples for classification purposes, and to evaluate
physical properties and engineering characteristics. Laboratory tests included: Expansion Index,
Grain Size Analysis, and Chemical Characteristics. Test descriptions and laboratory test results are
included in Appendix C.
4.0 GEOLOGY
4.1 General Setting
Carlsbad is located within the Peninsular Ranges physiographic province that is characterized by
northwest-trending mountain ranges, intervening valleys, and predominantly northwest trending
regional faults. The greater San Diego Region can be further subdivided into the coastal plain area,
a central mountain—valley area and the eastern mountain valley area. The project site is located
within the coastal plain area that is characterized by Cretaceous, Tertiary, and Quaternary
sedimentary deposits that onlap an eroded basement surface consisting of Jurassic and Cretaceous
crystalline rocks.
4.2 Geologic Conditions
Based on the regional geologic map prepared by Kennedy and Tan (2007), the near surface geologic
unit that underlies the site consists of Quaternary Old Paralic Deposits, Unit 6-7. Based on recent
explorations, Quaternary Undocumented Fill and Residual Soil were observed overlying the Old
Paralic Deposits. Based on nearby sea cliff exposures, regional geologic map relationships, previous
soil borings and known subsurface conditions in the site vicinity, we anticipate the Old Paralic
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Deposits are underlain by dense to very dense Eocene Santiago Formation materials at a depth of
generally less than 40 feet beneath the site. Descriptions of the geologic and soil units encountered
during the investigation are presented below.
4.2.1 Quaternary Undocumented Fill
Where observed, the Undocumented Fill generally consists of loose, dark brown to reddish
brown, silty fine to medium grained sand. Fills were observed to a maximum depth of
approximately 3.3 feet bgs, although isolated areas of deeper fill may be encountered
throughout the site during grading and construction.
4.2.2 Residual Soil
Where observed, the Residual Soil generally consists of medium dense, dark brown, silty
fine to medium grained sand. Exploratory excavations encountered Residual Soil to a
maximum depth of approximately 4.5 feet (bgs). This unit is relatively thin and blankets the
underlying Old Paralic Deposits.
4.2.3 Quaternary Old Paralic Deposits
Quaternary Old Paralic Deposits were observed in both the borings. Where observed, these
materials generally consist of medium dense, reddish brown, silty fme to medium grained
sandstone that was encountered to the maximum explored depth. As indicated, the site area
is underlain at depth by dense Eocene deposits.
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4.3 Groundwater Conditions
Groundwater was not observed in the recent site explorations, however, seepage was encountered at
an approximate depth of 15 feet bgs at a nearby project on Pine Avenue. While groundwater
conditions may vary, especially following periods of sustained precipitation or irrigation, it is not
generally anticipated to adversely affect shallow construction activities or the completed
improvements, if proper site drainage is designed, installed, and maintained as per the
recommendations of the project civil engineer of record. If deeper excavations are proposed,
groundwater may be encountered and would need to be addressed.
4.4 Geologic Hazards
Geologic hazards considered to have potential impacts to site development were evaluated based on
field observations, literature review, and laboratory test results. The following paragraphs discuss
geologic hazards considered and associated potential risk to the site.
4.4.1 Surface Fault Rupture
In accordance with the Aiquist-Priolo Earthquake Fault Zoning Act, (ACT), the State of
California established Earthquake Fault Zones around known active faults. The purpose of
the ACT is to regulate the development of structures intended for human occupancy near
active fault traces in order to mitigate hazards associated with surface fault rupture.
According to the California Geological Survey (Special Publication 42, Revised 2018), a
fault that has had surface displacement within the last 11,700 years is defined as a Holocene-
active fault and is either already zoned or pending zonation in accordance with the ACT.
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There are several other definitions of fault activity that are used to regulate dams, power
plants, and other critical facilities, and some agencies designate faults that are documented as
older than Holocene (last 11,700 years) and younger than late Quaternary (1.6 million years)
as potentially active faults that are subject to local jurisdictional regulations.
Based on the site reconnaissance and review of referenced literature, the site is not located
within a local or State-designated Earthquake Fault Zone, no known active fault traces
underlie or project toward the site, and no known potentially active fault traces project
toward the site. Therefore fault surface rupture potential is considered to be low at the
subject site.
4.4.2 Local and Regional Faulting
The United States Geological Survey (USGS), with support of State Geological Surveys, and
reviewed published work by various researchers, have developed a Quaternary Fault and
Fold Database of faults and associated folds that are believed to be sources of earthquakes
with magnitudes greater than 6.0 that have occurred during the Quaternary (the past 1.6
million years). The faults and folds within the database have been categorized into four
Classes (Class A-D) based on the level of evidence confirming that a Quaternary fault is of
tectonic origin and whether the structure is exposed for mapping or inferred from fault
related deformational features. Class A faults have been mapped and categorized based on
age of documented activity ranging from Historical faults (activity within last 150 years),
Latest Quaternary faults (activity within last 15,000 years), Late Quaternary (activity within
last 130,000 years), to Middle to late Quaternary (activity within last 1.6 million years). The
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Class A faults are considered to have the highest potential to generate earthquakes and/or
surface rupture, and the earthquake and surface rupture potential generally increases from
oldest to youngest. The evidence for Quaternary deformation and/or tectonic activity
progressively decreases for Class B and Class C faults. When geologic evidence indicates
that a fault is not of tectonic origin it is considered to be a Class D structure. Such evidence
includes joints, fractures, landslides, or erosional and fluvial scarps that resemble fault
features, but demonstrate a non-tectonic origin.
The nearest known Class A fault is the Newport-Inglewood-Rose Canyon fault zone (<1.6
million years), which is approximately 3.5 kilometers west of the site. The attached Figure 3
shows regional faults and seismicity with respect to the site.
4.4.3 Liquefaction and Seismic Settlement Evaluation
Liquefaction occurs when saturated fine-grained sands or silts lose their physical strengths
during earthquake-induced shaking and behave like a liquid. This is due to loss of
point-to-point grain contact and transfer of normal stress to the pore water. Liquefaction
potential varies with water level, soil type, material gradation, relative density, and probable
intensity and duration of ground shaking. Seismic settlement can occur with or without
liquefaction; it results from densification of loose soils.
The site is underlain at shallow depths by medium dense Old Paralic Deposits. Based on the
noted subsurface conditions, the potential for liquefaction or significant seismic settlement at
the site is considered to be low.
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4.4.4 Tsunamis and Seiche Evaluation
According to https://www.conservation.ca.gov/cgs/tsunanii/maps/san-diego the site is not
located within a tsunami inundation zone based on its distance from the Pacific Ocean and
elevation above sea level. Damage resulting from oscillatory waves (seiches) is considered
unlikely due to the absence of large nearby confined bodies of water.
4.4.5 Landsliding
According to mapping by Tan (1995), the site is considered "Marginally Susceptible" to
landsliding, and no landslides are mapped in the site area. In addition, evidence of landslides
or landslide potential was not observed during the field exploration at the relatively flat-lying
site. Based on these findings, landsliding is not considered to be a significant geologic
hazard at the subject site.
4.4.6 Compressible and Expansive Soils
The near surface Undocumented Fill and Residual Soil encountered at the site are considered
to be potentially compressible in their current condition. Therefore, it is recommended that
these soils be overexcavated and properly compacted beneath proposed improvement areas
as recommended herein and as determined to be necessary during construction. Based on the
field data, site observations, and CTE's experience with similar soils in the vicinity of the
site, medium dense native soils underlying the site are not considered to be subject to
significant compressibility under the anticipated loads.
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Based on the generally granular nature of the subgrade materials, soils at the site are
anticipated to exhibit Very Low expansion potential (Expansion Index of 20 or less).
Therefore, expansive soils are generally not anticipated to present significant adverse
impacts to site development. Additional evaluation of near-surface soils should be
performed based on field observations during grading and excavation activities.
4.4.7 Corrosive Soils
Soil environments detrimental to concrete generally have elevated levels of soluble sulfates
and/or pH levels less than 5.5. According to the American Concrete Institute (ACI) Table
318 4.3.1, specific guidelines have been provided for concrete where concentrations of
soluble sulfate (SO4) in soil exceed 0.10 percent by weight. These guidelines include low
water: cement ratios, increased compressive strength, and specific cement type requirements.
A minimum resistivity value less than approximately 5,000 ohm-cm and/or soluble chloride
levels in excess of 200 ppm generally indicate a corrosive environment for buried metallic
utilities and untreated conduits.
Based on representative area conditions, near-surface soils at the site are generally
anticipated to present a negligible corrosion potential for Portland cement concrete. It is also
interpreted that the site soils will have a low corrosive potential to buried metallic
improvements. However, it would likely be prudent for buried utilities to utilize plastic
piping and/or conduits, where feasible. However, CTE does not practice corrosion
engineering. Therefore, if corrosion of improvements is of more significant concern, a
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qualified corrosion engineer could be consulted. Verification of corrosivity should be
performed based on the results of the site specific testing.
5.0 CONCLUSIONS AND RECOMMENDATIONS
5.1 General
CTE concludes that the proposed improvements on the site are feasible from a geotechnical
standpoint, provided the preliminary recommendations in this report are incorporated into the design
and construction of the project. Recommendations for the proposed earthwork and improvements
are included in the following sections and Appendix D. However, recommendations in the text of
this report supersede those presented in Appendix D should conflicts exist. These preliminary
recommendations should either be confirmed as appropriate or updated following demolition of
existing improvements and observations during site preparation.
5.2 Site Preparation
Prior to grading, the site should be cleared of any existing construction debris and vegetation, not
suitable for structural backfill and be properly disposed of offsite. Based on the presence of
disturbed near surface soils overexcavation in areas to receive structures should extend to a
minimum depth of two feet below proposed foundations or to the depth of competent Old Paralic
Deposits, whichever is deeper. Overexcavation should extend laterally at least five feet beyond the
limits of the proposed improvements, where feasible.
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For other proposed improvements, such as pavement and hardscape areas, existing soils should be
excavated to the depth of two feet below proposed grades, or to the depth of competent underlying
materials, whichever is greater.
If encountered, existing below-ground utilities should be redirected around proposed structures.
Existing utilities at an elevation to extend through the proposed footings should generally be sleeved
and caulked to minimize the potential for moisture migration below the building slabs. Abandoned
pipes exposed by grading should be securely capped or filled with minimum two-sack cement/sand
slurry to help prevent moisture from migrating beneath foundation and slab soils.
Overexcavations adjacent to existing structures and property limits should generally not extend
below a 1:1 plane extended down from the bottom of the existing footings or as recommended
during grading based on the exposed conditions. Depending on the depth and proximity of the
existing building footings, alternating slot excavations could be required in localized areas during
earthwork.
A CTE representative should observe the exposed ground surface prior to placement of compacted
fill to document and verify the competency of the encountered subgrade materials. If unsuitable
material is exposed at the base of excavations additional removals may be recommended. After
approval by this office, the exposed subgrades to receive fill should be scarified a minimum of nine
inches, moisture conditioned, and properly compacted prior to additional compacted fill placement.
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5.3 Site Excavation
Based on CTE's observations, shallow excavations at the site should be feasible using well-
maintained heavy-duty construction equipment run by experienced operators. However, excavations
within the Old Paralic Deposits could encounter zones that are sensitive to caving and/or erosion,
and may not effectively remain standing vertical or near-vertical, even at shallow or minor heights
and for short periods of time.
5.4 Fill Placement and Compaction
Following the recommended overexcavation of loose or disturbed soils, the areas to receive fills
should be scarified approximately nine inches, moisture conditioned, and properly compacted. Fill
and backfill should be compacted to a minimum relative compaction of 90 percent at above optimum
moisture content, as evaluated by ASTM D 1557. The optimum lift thickness for fill soil depends on
the type of compaction equipment used. Generally, backfill should be placed in uniform, horizontal
lifts not exceeding eight inches in loose thickness. Fill placement and compaction should be
conducted in conformance with local ordinances, and should be observed and tested by a CTE
geotechnical representative.
5.5 Fill Materials
Properly moisture-conditioned very low to low expansion potential soils derived from the on-site
excavations are considered suitable for reuse on the site as compacted fill. If used, these materials
should be screened of organics and materials generally greater than three inches in maximum
dimension. Irreducible materials greater than three inches in maximum dimension should generally
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not be used in shallow fills (within three feet of proposed grades). In utility trenches, adequate
bedding should surround pipes.
Imported fill beneath structures, flatwork, and pavements should have an Expansion Index of 20 or
less (ASTM D 4829). Proposed import fill soils for use in structural or slope areas should be
evaluated by the geotechnical engineer before being transported to the site.
If retaining walls are proposed, backfill located within a 45-degree wedge extending up from the
heel of the wall should consist of soil having an Expansion Index of 20 or less (ASTM D 4829) with
less than 30 percent passing the No. 200 sieve. The upper 12 to 18 inches of wall backfill should
consist of lower permeability soils, in order to reduce surface water infiltration behind walls. The
project structural engineer and/or architect should detail proper wall backdrains, including gravel
drain zones, fills, filter fabric, and perforated drain pipes. However, a conceptual wall backdrain
detail, which may be suitable for use at the site, is provided as Figure 4.
5.6 Temporary Construction Slopes
The following recommended slopes should be relatively stable against deep-seated failure, but may
experience localized sloughing. On-site soils are considered Type B and Type C soils with
recommended slope ratios as set forth in Table 5.6.
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- TABLE 5.6
RECOMMENDED TEMPORARY SLOPE RATIOS
SOIL TYPE SLOPE RATIO MAXIMUM HEIGHT (Horizontal: vertical)
B (Old Paralic Deposits) 1:1 (OR FLATTER) 5 Feet
C (Undocumented Fill and 1.5:1 (OR FLATTER) 5 Feet Residual Soil)
Actual field conditions and soil type designations must be verified by a "competent person" while
excavations exist, according to Cal-OSHA regulations. In addition, the above sloping
recommendations do not allow for surcharge loading at the top of slopes by vehicular traffic,
equipment or materials. Appropriate surcharge setbacks must be maintained from the top of all
unshored slopes.
5.7 Foundations and Slab Recommendations
The following recommendations are for preliminary design purposes only. These foundation
recommendations should be re-evaluated after review of the project grading and foundation plans,
and after completion of rough grading of the building pad areas. Upon completion of rough pad
grading, Expansion Index of near surface soils should be verified, and these recommendations
should be updated, if necessary.
5.7.1 Foundations
Foundation recommendations presented herein are based on the anticipated very low to low
expansion potential of site soils (Expansion Index of 50 or less).
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Following the recommended preparatory grading, continuous and isolated spread footings
are anticipated to be suitable for use at this site. Foundation dimensions and reinforcement
should be based on allowable bearing values of 2,000 pounds per square foot (psf) for
minimum 15-inch wide footings embedded a minimum of 18-inches below lowest adjacent
subgrade elevation. Isolated footings should be at least 24 inches in minimum dimension.
The allowable bearing value may be increased by one-third for short-duration loading, which
includes the effects of wind or seismic forces. Based on the recommended preparatory
grading, it is anticipated that all footings will be founded entirely in properly compacted fill
materials. Footings should not span cut to fill interfaces.
Minimum reinforcement for continuous footings should consist of four No. 5 reinforcing
bars; two placed near the top and two placed near the bottom, or as per the project structural
engineer. The structural engineer should design isolated footing reinforcement. An
uncorrected subgrade modulus of 130 pounds per cubic inch is considered suitable for elastic
foundation design.
The structural engineer should provide recommendations for reinforcement of any spread
footings and footings with pipe penetrations. Footing excavations should generally be
maintained above optimum moisture content until concrete placement.
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5.7.2 Foundation Settlement
The maximum total static settlement is expected to be on the order of one inch and the
maximum differential settlement is expected to be on the order of 0.5 inch over a distance of
40 feet. Due to the generally dense nature of underlying materials, dynamic settlement is not
expected to adversely affect the proposed buildings.
5.7.3 Foundation Setback
Footings for structures should be designed such that the horizontal distance from the face of
adjacent slopes to the outer edge of the footing is at least 10 feet.. In addition, footings
should bear beneath a 1:1 plane extended up from the nearest bottom edge of adjacent
trenches and/or excavations. Deepening of affected footings may be a suitable means of
attaining the prescribed setbacks.
5.7.4 Interior Concrete Slabs
Lightly loaded concrete slabs should be a minimum of 4.5 inches thick. Minimum slab
reinforcement should consist of #4 reinforcing bars placed on maximum 18-inch centers,
each way, at or above mid-slab height, but with proper cover. More stringent
recommendations per the project structural engineer could be provided.
In moisture-sensitive floor areas, a suitable vapor retarder of at least 15-mil thickness (with
all laps or penetrations sealed or taped) overlying a four-inch layer of consolidated aggregate
base or gravel (with SE of 30 or more) should be installed. An optional maximum two-inch
layer of similar material may be placed above the vapor retarder to help protect the
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membrane during steel and concrete placement. This recommended protection is generally
considered typical in the industry. If proposed floor areas or coverings are considered
especially sensitive to moisture emissions, additional recommendations from a specialty
consultant could be obtained. CTE is not an expert at preventing moisture penetration
through slabs. A qualified architect or other experienced professional should be contacted if
moisture penetration is a more significant concern.
Slabs subjected to heavier loads may require thicker slab sections and/or increased
reinforcement. A 110-pci subgrade modulus is considered suitable for elastic design of
minimally embedded improvements such as slabs-on-grade.
Subgrade materials should be maintained or brought to a minimum of two percent or greater
above optimum moisture content until slab underlayment and concrete are placed.
5.8 Seismic Design Criteria
The seismic ground motion values listed in the table below were derived in accordance with the
ASCE 7-16 Standard that is incorporated into the 2019 California Building Code. This was
accomplished by establishing the Site Class based on the underlying soil properties at the site, and
calculating site coefficients and parameters using the using the SEAOC-OSHPD U.S. Seismic
Design Maps application. Seismic ground motion values are based on the approximate site
coordinates of 33.1556° latitude and -117.3446° longitude. These values are intended for the design
of structures to resist the effects of earthquake ground motions.
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February 25, 2020 CTE Job No. 10-13921S
TABLE 5.8 .
SEISMIC GROUND MOTION VALUES (CODE-BASED)• - -
PARAMETER
-
-
2019 CBC AND ASCE 7-16.
VALUE 2019 CBC/ASCE 7-16
REFERENCE
Site Class C ASCE 16, Chapter 20
Mapped Spectral Response 1.081 Figure 1613.2.1 (1) Acceleration Parameter, S
Mapped Spectral Response 0.391 Figure 1613.2.1 (2) Acceleration Parameter, S1
Seismic Coefficient, F. 1.2 Table 1613.2.3 (1)
Seismic Coefficient, F 1.5 Table 1613.2.3 (2)
MCE Spectral Response 1.298 Section 16 13.2.3 Acceleration Parameter, SMS
MCE Spectral Response 0.586 Section 1613.2.3
Acceleration Parameter, SMI
Design Spectral Response 0.865 Section 1613.2.5(l)
Acceleration, Parameter SDS
Design Spectral Response 0.391 Section 16 13.2.5 (2)
Acceleration, Parameter 5D1
Peak Ground Acceleration PGAM 0.573 ASCE 16, Section 11.8.3
5.9 Lateral Resistance and Earth Pressures
Lateral loads acting against structures may be resisted by friction between the footings and the
supporting soil or passive pressure acting against structures. If frictional resistance is used,
allowable coefficients of friction of 0.30 (total frictional resistance equals the coefficient of friction
multiplied by the dead load) for concrete cast directly against compacted fill is recommended. A
design passive resistance value of 250 pounds per square foot per foot of depth (with a maximum
value of 2,000 pounds per square foot) may be used. The allowable lateral resistance can be taken as
the sum of the frictional resistance and the passive resistance, provided the passive resistance does
not exceed two-thirds of the total allowable resistance.
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February 25, 2020 CTE Job No. lo-13921S
If proposed, retaining walls backfihled using granular soils may be designed using the equivalent
fluid unit weights given in Table 5.9 below.
TABLE 5.9
EQUIVALENT FLUID UNIT WEIGHTS (Gh)
(pounds per cubic foot)
SLOPE BACKFILL
WALL TYPE LEVEL BACKFILL 2:1 (HORIZONTAL:
VERTICAL)
CANTILEVER WALL 35 55 (YIELDING)
RESTRAINED WALL 55 65
Lateral pressures on cantilever retaining walls (yielding walls) over six feet high due to
earthquake motions may be calculated based on work by Seed and Whitman (1970). The total
lateral earth pressure against a properly drained and backfilled cantilever retaining wall above
the groundwater level can be expressed as:
PAE = PA + APAE
For non-yielding (or "restrained") walls, the total lateral earth pressure may be similarly
calculated based on work by Wood (1973):
PKE = PK + APKE
Where PA/b = Static Active Earth Pressure = GhH2/2
PK/b = Static Restrained Wall Earth Pressure = GhH2/2
APAFJb = Dynamic Active Earth Pressure Increment = (3/8) kh yH2/2
APKE/b = Dynamic Restrained Earth Pressure Increment = kh yH2/2
b = unit length of wall (usually 1 foot)
kh = 2/3 PGA.. (PGAm given previously Table 5.8)
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February 25, 2020 CTE Job No. 10-13921S
Oh = Equivalent Fluid Unit Weight (given previously Table 5.9)
H = Total Height of the retained soil
= Total Unit Weight of Soil 135 pounds per cubic foot
The static and increment of dynamic earth pressure in both cases may be applied with a line of
action located at H/3 above the bottom of the wall (SEAOC, 2013).
These values assume non-expansive backfill and free-draining conditions. Measures should be taken
to prevent moisture buildup behind all retaining walls. Drainage measures should include free-
draining backfill materials and sloped, perforated drains. These drains should discharge to an
appropriate off-site location. Figure 4 shows a conceptual wall backdrain detail that may be suitable
for walls at the subject site. Any waterproofing should be as specified by the project architect.
5.10 Exterior Flatwork
Flatwork should be installed with crack-control joints at appropriate spacing as designed by the
project architect to reduce the potential for cracking in exterior flatwork caused by minor movement
of subgrade soils and concrete shrinkage. Additionally, it is recommended that flatwork be installed
with at least number 4 reinforcing bars at 24-inch centers, each way, at or above mid-height of slab,
but with proper concrete cover, or with other reinforcement per the applicable project designer.
Flatwork that should be installed with crack control joints, includes driveways, sidewalks, and
architectural features. All subgrades should be prepared according to the earthwork
recommendations previously given before placing concrete. Positive drainage should be established
and maintained next to all flatwork. Subgrade materials should be maintained at a minimum of two
percent above optimum moisture content before concrete placement.
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5.11 Vehicular Pavement
The proposed improvements include paved vehicle drive and parking areas. Presented in Table 5.11
are preliminary pavement sections utilizing estimated Resistance "R" Value and traffic index. The
upper 12 inches of subgrade and all base materials should be compacted to 95% relative compaction
in accordance with ASTM D1557, and at a minimum of two percent above optimum moisture
content.
TABLE 5.11
RECOMMENDED PAVEMENT THICKNESS
Traffic Area Assumed Preliminary Asphalt Pavements Portland Cement
Traffic Index Subgrade Concrete AC Class II "R"-Value Thickness Aggregate Base Pavements, on
(inches) Thickness Subgrade Soils
(inches) (inches)
Automobile 5.0 30+ 3.0 6.0 6.5 Parking Areas
* Caltrans class 2 aggregate base
** Concrete should have a modulus of rupture of at least 600 psi
During or following rough site grading, CTE recommends laboratory testing at-grade soils for as-
graded "R"-Value.
Asphalt paved areas should be designed, constructed, and maintained in accordance with the
recommendations of the Asphalt Institute, or other widely recognized authority. Concrete paved
areas should be designed and constructed in accordance with the recommendations of the American
Concrete Institute or other widely recognized authority, particularly with regard to thickened edges,
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February 25, 2020 CTE Job No. 10-13921S
joints, and drainage. The Standard Specifications for Public Works construction ("Greenbook") or
Caltrans Standard Specifications may be referenced for pavement materials specifications.
5.12 Drainage
Surface runoff should be collected and directed away from improvements by means of appropriate
erosion-reducing devices and positive drainage should be established around the proposed
improvements. Positive drainage should be directed away from improvements at a gradient of at
least two percent for a distance of at least five feet. However, the project civil engineers should
evaluate the on-site drainage and make necessary provisions to keep surface water from affecting the
site.
Generally, CTE recommends against allowing water to infiltrate building pads or adjacent to slopes.
CTE understands that some agencies are encouraging the use of storm-water cleansing devices. Use
of such devices tends to increase the possibility of adverse effects associated with high groundwater
including slope instability and liquefaction.
5.13 Slopes
The site is generally flat and no significant slopes were observed. Based on anticipated soil strength
characteristics, fill slopes if proposed, should be constructed at slope ratios of 2:1 (horizontal:
vertical) or flatter. These fill slope inclinations should exhibit factors of safety greater than 1.5.
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February 25, 2020 CTE Job No. 10-13921S
Although properly constructed slopes on this site should be grossly stable, the soils will be
somewhat erodible. Therefore, runoff water should not be permitted to drain over the edges of
slopes unless that water is confined to properly designed and constructed drainage facilities.
Erosion-resistant vegetation should be maintained on the face of all slopes.
Typically, soils along the top portion of a fill slope face will creep laterally. CTE recommends
against building distress-sensitive hardscape improvements within five feet of slope crests.
5.14 Controlled Low Strength Materials (CLSM)
Controlled Low Strength Materials (CLSM) may be used in lieu of compacted soils below
foundations, within building pads, and/or adjacent to retaining walls or other structures, provided the
appropriate following recommendations are also incorporated. Minimum overexcavation depths
recommended herein beneath bottom of footings, slabs, flatwork, and other areas may be applicable
beneath CLSM if/where CLSM is to be used, and excavation bottoms should be observed by CTE
prior to placement of CLSM. Prior to CLSM placement, the excavation should be free of debris,
loose soil materials, and water. Once specific areas to utilize CLSM have been determined, CTE
should review the locations to determine if additional recommendations are appropriate.
CLSM should consist of a minimum three-sack cement/sand slurry with a minimum 28-day
compressive strength of 100 psi (or equal to or greater than the maximum allowable short term soil
bearing pressure provided herein, whichever is higher) as determined by ASTM D4832. If re-
excavation is anticipated, the compressive strength of CLSM should generally be limited to a
maximum of 150 psi per ACI 229R-99. Where re-excavation is required, two-sack cement/sand
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February 25, 2020 CTE Job No. 10-13921S
slurry may be used to help limit the compressive strength. The allowable soils bearing pressure and
coefficient of friction provided herein should still govern foundation design. CLSM may not be used
in lieu of structural concrete where required by the structural engineer.
5.15 Plan Review
CTE should be authorized to review the project grading and foundation plans prior to
commencement of earthwork in order to provide additional recommendations, if necessary.
5.16 Construction Observation
The recommendations provided in this report are based on preliminary design information for the
proposed construction and the subsurface conditions observed in the soil borings. The interpolated
subsurface conditions should be checked by CTE during construction with respect to anticipated
conditions. Upon completion of precise grading, if necessary, soil samples will be collected to
evaluate as-built Expansion Index. Foundation recommendations may be revised upon completion
of grading, and as-built laboratory tests results. Additionally, soil samples should be taken in
pavement subgrade areas upon rough grading to refme pavement recommendations as necessary.
Recommendations provided in this report are based on the understanding that CTE will provide the
observation and testing services for the project. All earthwork should be observed and tested in
accordance with recommendations contained within this report. CTE should evaluate footing
excavations before reinforcing steel placement.
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February 25, 2020 CTE Job No. 10-13921S
6.0 LIMITATIONS OF INVESTIGATION
The field evaluation, laboratory testing and geotechnical analysis presented in this report have been
conducted according to current engineering practice and the standard of care exercised by reputable
geotechnical consultants performing similar tasks in this area. No other warranty, expressed or
implied, is made regarding the conclusions, recommendations and opinions expressed in this report.
Variations may exist and conditions not observed or described in this report may be encountered
during construction. This report is prepared for the project as described. It is not prepared for any
other property or party.
The recommendations provided herein have been developed in order to reduce the post-construction
movement of site improvements. However, even with the design and construction recommendations
presented herein, some post-construction movement and associated distress may occur.
The findings of this report are valid as of the present date. However, changes in the conditions of a
property can occur with the passage of time, whether they are due to natural processes or the works
of man on this or adjacent properties. In addition, changes in applicable or appropriate standards
may occur, whether they result from legislation or the broadening of knowledge. Accordingly, the
findings of this report may be invalidated wholly or partially by changes outside CTE's involvement.
Therefore, this report is subject to review and should not be relied upon after a period of three years.
E5C_5ERVER\Projects\10-13000 to 10-13999 Projects\ 10- 13921 SRpt_Geotechnica1.doc
((C
No.1890
cERliFlED..% OGNEERING cEOLOQST*\F 5 /.1/,1
Geotechnical Investigation Page 26
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February 25, 2020 CTE Job No. 10-13921S
CTE's conclusions and recommendations are based on an analysis of the observed conditions. If
conditions different from those described in this report are encountered, CTE should be notified and
additional recommendations, if required, will be provided subject to CTE remaining as authorized
geotechnical consultant of record. This report is for use of the project as described. It should not be
utilized for any other project.
CTE's conclusions and recommendations are based on an analysis of the observed conditions. If
conditions different from those described in this report are encountered during construction, this
office should be notified and additional recommendations, if required, will be provided.
CTE appreciate this opportunity to be of service on this project. If you have any questions regarding
this report, please do not hesitate to contact the undersigned.
Respectfully submitted,
CONSTRUCTION TESTING & ENGINEERING, INC.
ESSI
(N:266
Dan T. Math, GE #2665 12/3h/ )
Principal Engineer
4
Aaron J. BLy, CEG 1101 #2603 Ii
Project Geologist
N~4,~,Z—FC~XVV DTM/JFL/AJB :ack
Jay F. Lynch, CEG #1890
Principal Engineering Geologist
No.2603
CERTIFIED
ENGINEERING
\\ESC_SERVER\Projects\1O-13000 to 10-13999 Projects10-13921 S\Rpt_Geotechnical.doc
st Western Plus
aci View L.
Dns Bistro
(y.
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e
-
- - A V
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o
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ts\10-1 3000 to 10-13999 Projects \10-139215\Figure 2.
12 0 6 12
Fill \ LEGEND
095
/ 1 Inch • a. 49
" --- HISTORIC FAULT DISPLACEMENT (LAST 200 YEARS)
_- 0 -. t ____--------•--• HOLOCENE FAULT DISPLACEMENT (DURING PAST 11,700 YEARS)
Ee
46 LATE QUATERNARY FAULT DISPLACMENT (DURING PAST 700,000 YEARS)
< - QUATERNARY FAULT DISPLACEMENT (AGE UNDIFFERENTIATED)
\ .
go,
PREQUATERNARY FAULT DISPLACEMENT (OLDER THAN 1 6 MILLION YEARS)
'1,1
It g 93
40
t! J73 1800- 1869- 1932- PERIOD 1868 1931 2010
CREEp"
'
1 7.0
1r: 6569 0 0
- __
\ _/ IQ ) 05.0-5.40 0
/
- / \ ( LAST TWO DIGITS OF M>6 5
EARTHQUAKE YEAR
'
S 5- -
\
- . AJIROXIMA'I',1
° SIll I OC A 1I( ) N ( 9 p \ / 1 JJ-4 N P- - - - •.
-
99
fu
7 Do
t I
ITO
(
\\\ \ \CREEP
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if 95
-
0
171A
S S
NOTES: FAULT ACTIVITY MAP OF CALIFORNIA, 2010, CALIFORNIA GEOLOGIC DATA MAP SERIES MAP NO. 6; REGIONAL FAULT AND SEISMICITY MAP CTE X N1O139215
EPICENTERS OF AND AREAS DAMAGED BY M>5 CALIFORNIA EARTHQUAKES, 1800-1999 ADAPTED \\ Construction Testing & Engineering, Inc. AFTER TOPPOZADA, BRANUM, PETERSEN, HAILSTORM, CRAMER, AND REICHLE, 2000, CTE Tf ' PROPOSED RESIDENTIAL DEVELOPMENT 1 inch = 12 miles
CDHG MAP SHEET 49 i1VL_,. 1441 Montiel Rd Ste 115, Escondido, CA 92026 Ph (760)746-4955 540 CHESTNUT AVENUE DATE
REFERENCE FOR ADDITIONAL EXPLANATION; MODIFIED WITH CISN AND USGS SEISMIC MAPS CARLSBAD, CALIFORNIA 2/20 3
12" TO 18" OF LOWER
PERMEABILITY NATIVE
MATERIAL COMPACTED TO 90%
RELATIVE COMPACTION
RETAINING W
FINISH GRADE
I,
V I
,4
I. L I& •
44
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I& S Ill
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a.
* p
Afy
p
> & S
• &p p••• > C • p
90
ACTION I
ij
INGTOBE
ARCHITECT
4DIA. PERFORATED PVC
IPE (SCHEDULE 40 OR
EQUIVALENT). MINIMUM
1% GRADIENT TO SUITABLE
OUTLET
WALL FOOTING
APPENDIX A
REFERENCES
REFERENCES
American Society for Civil Engineers, 2016, "Minimum Design Loads for Buildings and
Other Structures," ASCE/SEI 7-16.
ASTM, 2002, "Test Method for Laboratory Compaction Characteristics of Soil Using
Modified Effort," Volume 04.08
Blake, T.F., 2000, "EQFAULT," Version 3.00b, Thomas F. Blake Computer Services and
Software.
California Building Code, 2019, "California Code of Regulations, Title 24, Part 2, Volume 2
of 2," California Building Standards Commission, published by ICBO, June.
California Division of Mines and Geology, CD 2000-003 "Digital Images of Official Maps
of Alquist-Priolo Earthquake Fault Zones of California, Southern Region," compiled by
Martin and Ross.
California Emergency Management Agency/California Geological Survey, "Tsunami
Inundation Maps for Emergency Planning."
Hart, Earl W., Revised 1994, Revised 2018, "Fault-Rupture Hazard Zones in California,
Alquist Priolo, Special Studies Zones Act of 1972," California Division of Mines and
Geology, Special Publication 42.
Jennings, Charles W., 1994, "Fault Activity Map of California and Adjacent Areas" with
Locations and Ages of Recent Volcanic Eruptions.
Kennedy, M.P. and Tan, S.S., 2007, "Geologic Map of the Oceanside 30'x 60' Quadrangle,
California", California Geological Survey, Map No. 2.
Reichie, M., Bodin, P., and Brune, J., 1985, The June 1985 San Diego Bay Earthquake
swarm [abs]: EOS, v. 66, no. 46, p.952.
Seed, H.B., and R.V. Whitman, 1970, "Design of Earth Retaining Structures for Dynamic
Loads," in Proceedings, ASCE Specialty Conference on Lateral Stresses in the Ground and
Design of Earth-Retaining Structures, pp. 103-147, Ithaca, New York: Cornell University.
Tan, S. S., and Giffen, D. G., 1995, "Landslide Hazards in the Northern Part of the San
Diego Metropolitan Area, San Diego County, California: Oceanside and San Luis Rey
Quadrangles, Landslide Hazard Identification Map No. 35", California Department of
Conservation, Division of Mines and Geology, Open-File Report 95-04, State of California,
Division of Mines and Geology, Sacramento, California.
Wood, J.H. 1973, Earthquake-Induced Soil Pressures on Structures, Report EERL 73-05.
Pasadena: California Institute of Technology.
APPENDIX B
EXPLORATION LOGS
Construction Testing & Engineering, Inc. CrE imè. 1441 MontielRd Ste 115,Escondido, CA 92026 Ph (760) 746-4955
DEFINITION OF TERMS
PRIMARY DIVISIONS SYMBOLS SECONDARY DIVISIONS
GRAVELS CLEAN 4 (3W WELL GRADED GRAVELS, GRAVEL-SAND MIXTURES
MORE THAN GRAVELS LITTLE OR NO FINES -.—L .z;
GP
POORLY GRADED GRAVELS OR GRAVEL SAND MIXTURES, Z HALF OF <5% FINES
—' u COARSE LITTLE OF NO FINES
GRAVELS GM
SILTY GRAVELS, GRAVEL-SAN D-SILT MIXTURES, Oo -w N LL. FRACTION IS
—J W co LARGER THAN
NO.4 SIEVE WITH FINES NON-PLASTIC FINES
. GC , CLAYEY GRAVELS, GRAVEL-SAND-CLAY MIXTURES,
Z W PLASTIC FINES
SANDS CLEAN :::: w .:C WELL GRADED SANDS, GRAVELLY SANDS, LITTLE OR NO
W <c'i
0
MORE THAN
HALF OF
SANDS
<5% FINES
FINES
-
-.
SP
POORLY GRADED SANDS, GRAVELLY SANDS, LITTLE OR
<O WZ02 COARSE NO FINES
I(Il SILTY SANDS, SAND-SILT MIXTURES, NON-PLASTIC FINES o FRACTION IS
SMALLER THAN
NO.4 SIEVE
SANDS
WITH FINES
, sc CLAYEY SANDS, SAND-CLAY MIXTURES, PLASTIC FINES
W I I 1I,1,1.I1k
I ML I I I INORGANIC SILTS, VERY FINE SANDS, ROCK FLOUR, SILTY
SILTS AND CLAYS OR CLAYEY FINE SANDS, SLIGHTLY PLASTIC CLAYEY SILTS J.J.I..4J.I / CL
INORGANIC CLAYS OF LOW TO MEDIUM PLASTICITY, -JO...j U)
u- - Iij LIQUID LIMIT IS
(I)> LESS THAN 50 / GRAVELLY, SANDY, SILTS OR LEAN CLAYS 1
iuIi
ORGANIC SILTS AND ORGANIC CLAYS OF LOW PLASTICITY
ZZ Lh O
I U)
1h (MH II INORGANIC SILTS, MICACEOUS OR DIATOMACEOUS FINE
° w SILTS AND CLAYS SANDY OR SILTY SOILS. ELASTIC SILTS
INORGANIC CLAYS OF HIGH PLASTICITY, FAT CLAYS wck: W Z z o z LIQUID LIMIT IS
GREATER THAN 50 ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY,
ORGANIC SILTY CLAYS
HIGHLY ORGANIC SOILS PEAT AND OTHER HIGHLY ORGANIC SOILS
GRAIN SIZES
BOULDERS COBBLES GRAVEL I SAND I
I SILTS AND CLAYS COARSE I FINE I COARSE I MEDIUM I FINE
12" 3" 3/4" 4 10 40 200
CLEAR SQUARE SIEVE OPENING U.S. STANDARD SIEVE SIZE
ADDITIONAL TESTS
(OTHER THAN TEST PIT AND BORING LOG COLUMN HEADINGS)
MAX- Maximum Dry Density PM- Permeability PP- Pocket Penetrometer
OS- Grain Size Distribution SG- Specific Gravity WA- Wash Analysis
SE- Sand Equivalent HA- Hydrometer Analysis DS- Direct Shear
El- Expansion Index AL- Atterberg Limits UC- Unconfined Compression
CHM- Sulfate and Chloride RV- R-Value MD- Moisture/Density
Content, pH, Resistivity CN- Consolidation M- Moisture
COR — Corrosivity CP- Collapse Potential SC- Swell Compression
SD- Sample Disturbed HC- Hydrocollapse 01- Organic Impurities
REM- Remolded
FIGURE:I BL1
Construction Testing & Engineering, Inc. CTEi .
1441 Montiel Rd Ste 115, Escondido, CA 92026 Ph (760) 746-4955
PROJECT: DRILLER: SHEET: of
CTE JOB NO: DRILL METHOD: DRILLING DATE:
LOGGED BY: SAMPLE METHOD: ELEVATION:
.2 E 0. I '
!° BORING LEGEND Laboratory Tests
(I)
0 — .9 . •
DESCRIPTION
- - - Block or Chunk Sample - - -
-
- - - - Bulk Sample
.5-
-
- - - - - Standard Penetration Test
10 -
- - Modified Split-Barrel Drive Sampler (Cal Sampler) - - -
- [ - - Thin Walled Army Corp. of Engineers Sample - - -
15
- - Groundwater Table -
- -------------------------------------------------------------------------
- Soil Type or Classification Change
20
- Formation Change [(Approximate boundaries Queried (?)1
Quotes are placed around classifications where the soils
25 exist in situ as bedrock
FIGURE: I BL2
Testing & Engineering, Inc. C Construction
1441 Montiel Rd Ste 115, Escondido, CA 92026 Ph (760) 746-4955
PROJECT: PROPOSED RESIDENTAL DEVELOPMENT DRILLER: BAJA EXPLORATION SHEET: 1 of
CTE JOB NO: 540 CHESTNUT AVENUE DRILL METHOD: HOLLOW-STEM AUGER DRILLING DATE: 1/1612020
LOGGED BY: MB SAMPLE METHOD: RING, SET and BULK ELEVATION: -49 FEET
-'
-
E I BORING: B-i Laboratory Tests
'' •
CL
. a
DESCRIPTION
- - - -
- QUATERNARY UNDOCUMENTED FILL:
- Loose, moist, dark brown, silty fine to medium grained SAND.
Becomes reddish brown
- SM RESIDUAL SOIL:
- Medium dense, moist, dark brown, silty fine to medium grained
"SM' ', SAND. oxidized, massive. - GS QUATERNARY OLD PARALIC DEPOSITS:
- Medium dense, moist, reddish brown, silty fine to medium grained
SAND, oxidized, massive.
- Fine gravel
Medium dense, moist, reddish gray, poorly graded fine grained
- SAND with silt, friable. - - - -
- Total Depth: 10'
No Groundwater Encountered
-13
-26
-25 — — I B- 1
Construction Testing & Engineering, Inc. CTEI .
1441 Montiel Rd Ste 115, Escondido, CA 92026 Ph (760) 746-4955
PROJECT: PROPOSED RESIDENTAL DEVELOPMENT DRILLER: BAJA EXPLORATION SHEET: 1 of
CTE JOB NO: 540 CHESTNUT AVENUE DRILL METHOD: HOLLOW-STEM AUGER DRILLING DATE: 1/16/2020
LOGGED BY: KB SAMPLE METHOD: RING, SPT and BULK ELEVATION: -49 FEET
.3
B-2 I BORING: Laboratory Tests
'M to 2
U
Q FQ
6 Vi a
0
DESCRIPTION
- - - -
- RESIDUAL SOIL:
- Loose to medium dense, moist, dark brown, silty fine to medium
cirained SAND.
"SM" QUATERNARY OLD PARALIC DEPOSITS: - Medium dense, moist, reddish brown, silty fine to medium grained
- SAND, oxidized, massive. El, CFIM
- Total Depth: 5'
No Groundwater Encountered
-15
25
I B-2
APPENDIX C
LABORATORY METHODS AND RESULTS
LABORATORY METHODS AND RESULTS
Laboratory Testing Program
Laboratory tests were performed on representative soil samples to detect their relative engineering
properties. . Tests were performed following test methods of the American Society for Testing
Materials or other accepted standards. The following presents a brief description of the various test
methods used. -
Classification
Soils were classified visually according to the Unified Soil Classification System. Visual
classifications were supplemented by laboratory testing of selected samples according to ASTM
D2487. The soil classifications are shown on the Exploration Logs in Appendix B.
Expansion Index
Expansion testing was performed on selected samples of the matrix of the on-site soils according to
ASTM D 4829.
Particle-Size Analysis
Particle-size analyses were performed on selected representative samples according to ASTM D 422.
Chemical Analysis
Soil materials were collected with sterile sampling equipment and tested for Sulfate and Chloride
content, pH, Corrosivity, and Resistivity.
Construction Testing & Engineering, Inc.
1441 Montiel Rd Ste 115, Escondido, CA 92026 Ph (760) 746-4955
EXPANSION INDEX TEST
ASTMD 4829
LOCATION DEPTH EXPANSION INDEX EXPANSION
(feet) POTENTIAL
B-2 0-5 0 VERY LOW
SULFATE
LOCATION DEPTH RESULTS
(feet) ppm
B-2 0-5 20.9
CHLORIDE
LOCATION DEPTH RESULTS
(feet) ppm
B-2 0-5 2.7
ml
LOCATION DEPTH RESULTS
(feet)
B-2 0-5 7.57
RESISTIVITY
CALIFORNIA TEST 424
LOCATION DEPTH RESULTS
(feet) ohms-cm
B-2 0-5 23700
LABORATORY SUMMARY CIE JOB NO. 10-13921S
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PARTICLE SIZE ANALYSIS
Construction Testing & Engineer in g, Inc.
1441 Montiel Rd Ste 115, [.i Escondido,__
Appendix D Page D-1
Standard Specifications for Grading
Section 1 - General
Construction Testing & Engineering, Inc. presents the following standard recommendations for
grading and other associated operations on construction projects. These guidelines should be
considered a portion of the project specifications. Recommendations contained in the body of
the previously presented soils report shall supersede the recommendations and or requirements as
specified herein. The project geotechnical consultant shall interpret disputes arising out of
interpretation of the recommendations contained in the soils report or specifications contained
herein.
Section 2 - Responsibilities of Project Personnel
The geotechnical consultant should provide observation and testing services sufficient to general
conformance with project specifications and standard grading practices. The geotechnical
consultant should report any deviations to the client or his authorized representative.
The Client should be chiefly responsible for all aspects of the project. He or his authorized
representative has the responsibility of reviewing the findings and recommendations of the
geotechnical consultant. He shall authorize or cause to have authorized the Contractor and/or
other consultants to perform work and/or provide services. During grading the Client or his
authorized representative should remain on-site or should remain reasonably accessible to all
concerned parties in order to make decisions necessary to maintain the flow of the project.
The Contractor is responsible for the safety of the project and satisfactory completion of all
grading and other associated operations on construction projects, including, but not limited to,
earth work in accordance with the project plans, specifications and controlling agency
requirements.
Section 3 - Preconstruction Meeting
A preconstruction site meeting should be arranged by the owner and/or client and should include
the grading contractor, design engineer, geotechnical consultant, owner's representative and
representatives of the appropriate governing authorities.
Section 4- Site Preparation
The client or contractor should obtain the required approvals from the controlling authorities for
the project prior, during and/or after demolition, site preparation and removals, etc. The
appropriate approvals should be obtained prior to proceeding with grading operations.
STANDARD SPECIFICATIONS OF GRADING
Page 1 of 26
Appendix D Page D-2
Standard Specifications for Grading
Clearing and grubbing should consist of the removal of vegetation such as brush, grass, woods,
stumps, trees, root of trees and otherwise deleterious natural materials from the areas to be
graded. Clearing and grubbing should extend to the outside of all proposed excavation and fill
areas.
Demolition should include removal of buildings, structures, foundations, reservoirs, utilities
(including underground pipelines, septic tanks, leach fields, seepage pits, cisterns, mining shafts,
tunnels, etc.) and other man-made surface and subsurface improvements from the areas to be
graded. Demolition of utilities should include proper capping and/or rerouting pipelines at the
project perimeter and cutoff and capping of wells in accordance with the requirements of the
governing authorities and the recommendations of the geotechnical consultant at the time of
demolition.
Trees, plants or man-made improvements not planned to be removed or demolished should be
protected by the contractor from damage or injury.
Debris generated during clearing, grubbing and/or demolition operations should be wasted from
areas to be graded and disposed off-site. Clearing, grubbing and demolition operations should be
performed under the observation of the geotechnical consultant.
Section 5 - Site Protection
Protection of the site during the period of grading should be the responsibility of the contractor.
Unless other provisions are made in writing and agreed upon among the concerned parties,
completion of a portion of the project should not be considered to preclude that portion or
adjacent areas from the requirements for site protection until such time as the entire project is
complete as identified by the geotechnical consultant, the client and the regulating agencies.
Precautions should be taken during the performance of site clearing, excavations and grading to
protect the work site from flooding, ponding or inundation by poor or improper surface drainage.
Temporary provisions should be made during the rainy season to adequately direct surface
drainage away from and off the work site. Where low areas cannot be avoided, pumps should be
kept on hand to continually remove water during periods of rainfall.
Rain related damage should be considered to include, but may not be limited to, erosion, silting,
saturation, swelling, structural distress and other adverse conditions as determined by the
geotechnical consultant. Soil adversely affected should be classified as unsuitable materials and
should be subject to overexcavation and replacement with compacted fill or other remedial
grading as recommended by the geotechnical consultant.
STANDARD SPECIFICATIONS OF GRADING
Page 2 of 26
Appendix D Page D-3
Standard Specifications for Grading
The contractor should be responsible for the stability of all temporary excavations.
Recommendations by the geotechnical consultant pertaining to temporary excavations (e.g.,
backcuts) are made in consideration of stability of the completed project and, therefore, should
not be considered to preclude the responsibilities of the contractor. Recommendations by the
geotechnical consultant should not be considered to preclude requirements that are more
restrictive by the regulating agencies. The contractor should provide during periods of extensive
rainfall plastic sheeting to prevent unprotected slopes from becoming saturated and unstable.
When deemed appropriate by the geotechnical consultant or governing agencies the contractor
shall install checkdams, desilting basins, sand bags or other drainage control measures.
In relatively level areas and/or slope areas, where saturated soil and/or erosion gullies exist to
depths of greater than 1.0 foot; they should be overexcavated and replaced as compacted fill in
accordance with the applicable specifications. Where affected materials exist to depths of 1.0
foot or less below proposed finished grade, remedial grading by moisture conditioning in-place,
followed by thorough recompaction in accordance with the applicable grading guidelines herein
may be attempted. If the desired results are not achieved, all affected materials should be
overexcavated and replaced as compacted fill in accordance with the slope repair
recommendations herein. If field conditions dictate, the geotechnical consultant may
recommend other slope repair procedures.
Section 6- Excavations
6.1 Unsuitable Materials
Materials that are unsuitable should be excavated under observation and
recommendations of the geotechnical consultant. Unsuitable materials include, but may
not be limited to, dry, loose, soft, wet, organic compressible natural soils and fractured,
weathered, soft bedrock and nonengineered or otherwise deleterious fill materials.
Material identified by the geotechnical consultant as unsatisfactory due to its moisture
conditions should be overexcavated; moisture conditioned as needed, to a uniform at or
above optimum moisture condition before placement as compacted fill.
If during the course of grading adverse geotechnical conditions are exposed which were
not anticipated in the preliminary soil report as determined by the geotechnical consultant
additional exploration, analysis, and treatment of these problems may be recommended.
STANDARD SPECIFICATIONS OF GRADING
Page 3 of 26
Appendix D Page D-4
Standard Specifications for Grading
6.2 Cut Slopes
Unless otherwise recommended by the geotechnical consultant and approved by the
regulating agencies, permanent cut slopes should not be steeper than 2:1 (horizontal:
vertical).
The geotechnical consultant should observe cut slope excavation and if these excavations
expose loose cohesionless, significantly fractured or otherwise unsuitable material, the
materials should be overexcavated and replaced with a compacted stabilization fill. If
encountered specific cross section details should be obtained from the Geotechnical
Consultant.
When extensive cut slopes are excavated or these cut slopes are made in the direction of
the prevailing drainage, a non-erodible diversion swale (brow ditch) should be provided
at the top of the slope.
6.3 Pad Areas
All lot pad areas, including side yard terrace containing both cut and fill materials,
transitions, located less than 3 feet deep should be overexcavated to a depth of 3 feet and
replaced with a uniform compacted fill blanket of 3 feet. Actual depth of overexcavation
may vary and should be delineated by the geotechnical consultant during grading,
especially where deep or drastic transitions are present.
For pad areas created above cut or natural slopes, positive drainage should be established
away from the top-of-slope. This may be accomplished utilizing a berm drainage swale
and/or an appropriate pad gradient. A gradient in soil areas away from the top-of-slopes
of 2 percent or greater is recommended.
Section 7 - Compacted Fill
All fill materials should have fill quality, placement, conditioning and compaction as specified
below or as approved by the geotechnical consultant.
7.1 Fill Material Quality
Excavated on-site or import materials which are acceptable to the geotechnical consultant
may be utilized as compacted fill, provided trash, vegetation and other deleterious
materials are removed prior to placement. All import materials anticipated for use on-site
should be sampled tested and approved prior to and placement is in conformance with the
requirements outlined.
STANDARD SPECIFICATIONS OF GRADING
Page 4 of 26
Appendix D Page D-5
Standard Specifications for Grading
Rocks 12 inches in maximum and smaller may be utilized within compacted fill provided
sufficient fill material is placed and thoroughly compacted over and around all rock to
effectively fill rock voids. The amount of rock should not exceed 40 percent by dry
weight passing the 3/4-inch sieve. The geotechnical consultant may vary those
requirements as field conditions dictate.
Where rocks greater than 12 inches but less than four feet of maximum dimension are
generated during grading, or otherwise desired to be placed within an engineered fill,
special handling in accordance with the recommendations below. Rocks greater than
four feet should be broken down or disposed off-site.
7.2 Placement of Fill
Prior to placement of fill material, the geotechnical consultant should observe and
approve the area to receive fill. After observation and approval, the exposed ground
surface should be scarified to a depth of 6 to 8 inches. The scarified material should be
conditioned (i.e. moisture added or air dried by continued discing) to achieve a moisture
content at or slightly above optimum moisture conditions and compacted to a minimum
of 90 percent of the maximum density or as otherwise recommended in the soils report or
by appropriate government agencies.
Compacted fill should then be placed in thin horizontal lifts not exceeding eight inches in
loose thickness prior to compaction. Each lift should be moisture conditioned as needed,
thoroughly blended to achieve a consistent moisture content at or slightly above optimum
and thoroughly compacted by mechanical methods to a minimum of 90 percent of
laboratory maximum dry density. Each lift should be treated in a like manner until the
desired finished grades are achieved.
The contractor should have suitable and sufficient mechanical compaction equipment and
watering apparatus on the job site to handle the amount of fill being placed in
consideration of moisture retention properties of the materials and weather conditions.
When placing fill in horizontal lifts adjacent to areas sloping steeper than 5:1 (horizontal:
vertical), horizontal keys and vertical benches should be excavated into the adjacent slope
area. Keying and benching should be sufficient to provide at least six-foot wide benches
and a minimum of four feet of vertical bench height within the firm natural ground, firm
bedrock or engineered compacted fill. No compacted fill should be placed in an area
after keying and benching until the geotechnical consultant has reviewed the area.
Material generated by the benching operation should be moved sufficiently away from
STANDARD SPECIFICATIONS OF GRADING
Page 5 of 26
Appendix D Page D-6
Standard Specifications for Grading
the bench area to allow for the recommended review of the horizontal bench prior to
placement of fill.
Within a single fill area where grading procedures dictate two or more separate fills,
temporary slopes (false slopes) may be created. When placing fill adjacent to a false
slope, benching should be conducted in the same manner as above described. At least a
3-foot vertical bench should be established within the firm core of adjacent approved
compacted fill prior to placement of additional fill. Benching should proceed in at least
3-foot vertical increments until the desired finished grades are achieved.
Prior to placement of additional compacted fill following an overnight or other grading
delay, the exposed surface or previously compacted fill should be processed by
scarification, moisture conditioning as needed to at or slightly above optimum moisture
content, thoroughly blended and recompacted to a minimum of 90 percent of laboratory
maximum thy density. Where unsuitable materials exist to depths of greater than one
foot, the unsuitable materials should be over-excavated.
Following a period of flooding, rainfall or overwatering by other means, no additional fill
should be placed until damage assessments have been made and remedial grading
performed as described herein.
Rocks 12 inch in maximum dimension and smaller may be utilized in the compacted fill
provided the fill is placed and thoroughly compacted over and around all rock. No
oversize material should be used within 3 feet of finished pad grade and within 1 foot of
other compacted fill areas. Rocks 12 inches up to four feet maximum dimension should
be placed below the upper 10 feet of any fill and should not be closer than 15 feet to any
slope face. These recommendations could vary as locations of improvements dictate.
Where practical, oversized material should not be placed below areas where structures or
deep utilities are proposed. Oversized material should be placed in windrows on a clean,
overexcavated or unyielding compacted fill or firm natural ground surface. Select native
or imported granular soil (S.E. 30 or higher) should be placed and thoroughly flooded
over and around all windrowed rock, such that voids are filled. Windrows of oversized
material should be staggered so those successive strata of oversized material are not in
the same vertical plane.
It may be possible to dispose of individual larger rock as field conditions dictate and as
recommended by the geotechnical consultant at the time of placement.
STANDARD SPECIFICATIONS OF GRADING
Page 6 of 26
Appendix D Page D-7
Standard Specifications for Grading
The contractor should assist the geotechnical consultant and/or his representative by
digging test pits for removal determinations and/or for testing compacted fill. The
contractor should provide this work at no additional cost to the owner or contractor's
client.
Fill should be tested by the geotechnical consultant for compliance with the
recommended relative compaction and moisture conditions. Field density testing should
conform to ASTM Method of Test D 1556-00, D 2922-04. Tests should be conducted at
a minimum of approximately two vertical feet or approximately 1,000 to 2,000 cubic
yards of fill placed. Actual test intervals may vary as field conditions dictate. Fill found
not to be in conformance with the grading recommendations should be removed or
otherwise handled as recommended by the geotechnical consultant.
7.3 Fill Slopes
Unless otherwise recommended by the geotechnical consultant and approved by the
regulating agencies, permanent fill slopes should not be steeper than 2:1 (horizontal:
vertical).
Except as specifically recommended in these grading guidelines compacted fill slopes
should be over-built two to five feet and cut back to grade, exposing the firm, compacted
fill inner core. The actual amount of overbuilding may vary as field conditions dictate. If
the desired results are not achieved, the existing slopes should be overexcavated and
reconstructed under the guidelines of the geotechnical consultant. The degree of
overbuilding shall be increased until the desired compacted slope surface condition is
achieved. Care should be taken by the contractor to provide thorough mechanical
compaction to the outer edge of the overbuilt slope surface.
At the discretion of the geotechnical consultant, slope face compaction may be attempted
by conventional construction procedures including backrolling. The procedure must
create a firmly compacted material throughout the entire depth of the slope face to the
surface of the previously compacted firm fill intercore.
During grading operations, care should be taken to extend compactive effort to the outer
edge of the slope. Each lift should extend horizontally to the desired finished slope
surface or more as needed to ultimately established desired grades. Grade during
construction should not be allowed to roll off at the edge of the slope. It may be helpful
to elevate slightly the outer edge of the slope. Slough resulting from the placement of
individual lifts should not be allowed to drift down over previous lifts. At intervals not
STANDARD SPECIFICATIONS OF GRADING.
Page 7 of 26
Appendix D Page D-8
Standard Specifications for Grading
exceeding four feet in vertical slope height or the capability of available equipment,
whichever is less, fill slopes should be thoroughly dozer trackrolled.
For pad areas above fill slopes, positive drainage should be established away from the
top-of-slope. This may be accomplished using a berm and pad gradient of at least two
percent.
Section 8 - Trench Backfill
Utility and/or other excavation of trench backfill should, unless otherwise recommended, be
compacted by mechanical means. Unless otherwise recommended, the degree of compaction
should be a minimum of 90 percent of the laboratory maximum density.
Within slab areas, but outside the influence of foundations, trenches up to one foot wide and two
feet deep may be backfilled with sand and consolidated by jetting, flooding or by mechanical
means. If on-site materials are utilized, they should be wheel-rolled, tamped or otherwise
compacted to a firm condition. For minor interior trenches, density testing may be deleted or
spot testing may be elected if deemed necessary, based on review of backfill operations during
construction.
If utility contractors indicate that it is undesirable to use compaction equipment in close
proximity to a buried conduit, the contractor may elect the utilization of light weight mechanical
compaction equipment and/or shading of the conduit with clean, granular material, which should
be thoroughly jetted in-place above the conduit, prior to initiating mechanical compaction
procedures. Other methods of utility trench compaction may also be appropriate, upon review of
the geotechnical consultant at the time of construction.
In cases where clean granular materials are proposed for use in lieu of native materials or where
flooding or jetting is proposed, the procedures should be considered subject to review by the
geotechnical consultant. Clean granular backfill and/or bedding are not recommended in slope
areas.
Section 9 - Drainage
Where deemed appropriate by the geotechnical consultant, canyon subdrain systems should be
installed in accordance with CTE's recommendations during grading.
Typical subdrains for compacted fill buttresses, slope stabilization or sidehill masses, should be
installed in accordance with the specifications.
STANDARD SPECIFICATIONS OF GRADING
Page 8 of 26
Appendix D Page D-9
Standard Specifications for Grading
Roof, pad and slope drainage should be directed away from slopes and areas of structures to
suitable disposal areas via non-erodible devices (i.e., gutters, downspouts, and concrete swales).
For drainage in extensively landscaped areas near structures, (i.e., within four feet) a minimum
of 5 percent gradient away from the structure should be maintained. Pad drainage of at least 2
percent should be maintained over the remainder of the site.
Drainage patterns established at the time of fine grading should be maintained throughout the life
of the project. Property owners should be made aware that altering drainage patterns could be
detrimental to slope stability and foundation performance.
Section 10 - Slope Maintenance
10.1 - Landscape Plants
To enhance surficial slope stability, slope planting should be accomplished at the
completion of grading. Slope planting should consist of deep-rooting vegetation
requiring little watering. Plants native to the southern California area and plants relative
to native plants are generally desirable. Plants native to other semi-arid and and areas
may also be appropriate. A Landscape Architect should be the best party to consult
regarding actual types of plants and planting configuration.
10.2 - Irrigation
Irrigation pipes should be anchored to slope faces, not placed in trenches excavated into
slope faces.
Slope irrigation should be minimized. If automatic timing devices are utilized on
irrigation systems, provisions should be made for interrupting normal irrigation during
periods of rainfall.
10.3 - Repair
As a precautionary measure, plastic sheeting should be readily available, or kept on hand,
to protect all slope areas from saturation by periods of heavy or prolonged rainfall. This
measure is strongly recommended, beginning with the period prior to landscape planting.
If slope failures occur, the geotechnical consultant should be contacted for a field review
of site conditions and development of recommendations for evaluation and repair.
If slope failures occur as a result of exposure to period of heavy rainfall, the failure areas
and currently unaffected areas should be covered with plastic sheeting to protect against
additional saturation.
STANDARD SPECIFICATIONS OF GRADING
Page 9 of 26
Appendix D Page D-1O
Standard Specifications for Grading.
In the accompanying Standard Details, appropriate repair procedures are illustrated for
superficial slope failures (i.e., occurring typically within the outer one foot to three feet of
a slope face).
STANDARD SPECIFICATIONS OF GRADING
Page 10 of 26
BENCHING FILL OVER NATURAL
SURFACE OF FIRM
EARTH MATERIAL
FILL SLOPE
MIN M TLJ 10,
TYPICAL
15' MIN. (INCLINED 2% MIN. INTO SLOPE)
BENCHING FILL OVER CUT
SURFACE OF FIRM
EARTH MATERIAL
FINISH FILL SLOPE
FINISH CUT
SLOPE
2% MIN 10,
TYPICAL
15' MIN OR STABILITY EQUIVALENT PER SOIL
ENGINEERING (INCLINED 2% MIN. INTO SLOPE)
NOT TO SCALE
BENCHING FOR COMPACTED FILL DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 11 0f26
TOE OF SLOPE SHOWN
ON GRADING PLAN
FILL
-.
•
1Jç4'
.01
10' TYPICAL BENCH
WIDTH VARIES
COMPETENT EARTH
MATERIAL
At 2% MIN
MINIMUM _/ " 15' MINIMUM BASE KEY WIDTH
DOWNSLOPE
KEY DEPTH
TYPICAL BENCH
HEIGHT
PROVIDE BACKDRAIN AS REQUIRED
PER RECOMMENDATIONS OF SOILS
ENGINEER DURING GRADING
WHERE NATURAL SLOPE GRADIENT IS 5:1 OR LESS,
BENCHING IS NOT NECESSARY. FILL IS NOT TO BE
PLACED ON COMPRESSIBLE OR UNSUITABLE MATERIAL.
NOT TO SCALE
FILL SLOPE ABOVE NATURAL GROUND DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 12 of 26
REMOVE ALL TOPSOIL, COLLUVIUM,
AND CREEP MATERIAL FROM
TRANSITION
CUT/FILL CONTACT SHOWN
ON GRADING PLAN
FILL
cn -I
Z 0 CUT/FILL CONTACT SHOWN -
an ON "AS-BUILT"
C 'TYPICAL Cl) -
3 C)
- NATURAL
o TOPOGRAPHY - 2% MIN 10' TYPICAL
CA)>
z 15' MINIMUM
0) Ci') CUT SLOPE* BEDROCK OR APPROVED
m 0 FOUNDATION MATERIAL
C)
> C
Z *NOTE: CUT SLOPE PORTION SHOULD BE C) MADE PRIOR TO PLACEMENT OF FILL
NOT TO SCALE
FILL SLOPE ABOVE CUT SLOPE DETAIL
j— SURFACE OF
I COMPETENT
MATERIAL
----------------- -
,1
COMPACTED FILL
TYPICAL BENCHING
REMOVE UNSUITABLE
MATERIAL
SEE DETAIL BELOW
INCLINE TOWARD DRAIN
AT 2% GRADIENT MINIMUM
DETAIL
MINIMUM 9 FT3 PER LINEAR FOOT MINIMUM 4" DIAMETER APPROVED
OF APPROVED FILTER MATERIAL PERFORATED PIPE (PERFORATIONS
DOWN)
6" FILTER MATERIAL BEDDING
14"
MINIMUM
CALTRANS CLASS 2 PERMEABLE MATERIAL
FILTER MATERIAL TO MEET FOLLOWING
SPECIFICATION OR APPROVED EQUAL:
SIEVE SIZE PERCENTAGE PASSING
1" 100
3,4" 90-100
3%is 40-100
NO.4 25-40
NO.8 18-33
NO. 30 5-15
NO. 50 0-7
NO. 200
APPROVED PIPE TO BE SCHEDULE 40
POLY-VINYL-CHLORIDE (P.V.C.) OR
APPROVED EQUAL. MINIMUM CRUSH
STRENGTH 1000 psi
PIPE DIAMETER TO MEET THE
FOLLOWING CRITERIA, SUBJECT TO
FIELD REVIEW BASED ON ACTUAL
GEOTECHNICAL CONDITIONS
ENCOUNTERED DURING GRADING
LENGTH OF RUN PIPE DIAMETER
INITIAL 500' 4"
500' TO 1500' 6"
> 1500' 8"
0-3 NOT TO SCALE
TYPICAL CANYON SUBDRAIN DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 14 of 26
CANYON SUBDRAIN DETAILS
,- SURFACE OF
/ COMPETENT
MATERIAL
__)j
COMPACTED FILL
TYPICAL BENCHING
'% '°•° Ole
REMOVE UNSUITABLE
MATERIAL
SEE DETAILS BELOW
INCLINE TOWARD DRAIN
AT 2% GRADIENT MINIMUM
TRENCH DETAILS
6" MINIMUM OVERLAP
OPTIONAL V-DITCH DETAIL
-
MINIMUM 9 FPPER LINEAR FOOT
OF APPROVED DRAIN MATERIAL
MIRAFI 140N FABRIC
OR APPROVED EQUAL MIRAFI 140N FABRIC
OR APPROVED EQUAL
6" MINIMUM OVERLAP
MINIMUM
24"
MINIMUM 9 FT PER LINEAR FOOT
OF APPROVED DRAIN MATERIAL
60° TO 90°
APPROVED PIPE TO BE
SCHEDULE 40 POLY-
VINYLCHLORIDE (P.V.C.)
OR APPROVED EQUAL.
MINIMUM CRUSH STRENGTH
1000 PSI.
DRAIN MATERIAL TO MEET FOLLOWING
SPECIFICATION OR APPROVED EQUAL:
SIEVE SIZE PERCENTAGE PASSING
PIPE DIAMETER TO MEET THE
FOLLOWING CRITERIA, SUBJECT TO
FIELD REVIEW BASED ON ACTUAL
GEOTECHNICAL CONDITIONS
ENCOUNTERED DURING GRADING
1 Y2" 88-100
1" 5-40
3/411 0-17
0-7
NO. 200 0-3
LENGTH OF RUN
INITIAL 500'
500' TO 1500'
> 1500'
NOT TO SCALE
PIPE DIAMETER
4,'
6"
8"
GEOFABRIC SUBDRAIN
STANDARD SPECIFICATIONS FOR GRADING
Page 15 of 26
FRONT VIEW
-----
CONCRETE ,. 6" Mm.
CUT-OFF WALL : •'.. '
•
L L
'j)
SUBDRAIN PIPE 6" Mm.
24" Mm. -I
6" Mm.
SIDE VIEW
12" Mm. 6" Min.
CONCRETE
CUT-OFF WALL I_6"Mm.
Q SOILD SUBDRAIN PIPE " PERFORATED SUBDRAIN PIPE
NOT TO SCALE
RECOMMENDED SUBDRAIN CUT-OFF WALL
STANDARD SPECIFICATIONS FOR GRADING
Page 16 of 26
FRONT VIEW
. !0 _'. _ .. . .. . ..
A
,.
24" Min.
A • p. •
- ._ ._ -
I' •%
% A
-• - V . - V•
¼b..%b 'b.
' A • %.•
24" Mm.
SUBDRAIN OUTLET
PIPE (MINIMUM 4" DIAMETER)
SIDE VIEW
ALL BACKFILL SHOULD BE COMPACTED
IN CONFORMANCE WITH PROJECT
SPECIFICATIONS. COMPACTION EFFORT
SHOULD NOT DAMAGE STRUCTURE
CONCRETE
HEADWALL -
-. ''_.
_V .'V . -
24" Mm.
NOTE: HEADWALL SHOULD OUTLET AT TOE OF SLOPE
OR INTO CONTROLLED SURFACE DRAINAGE DEVICE
ALL DISCHARGE SHOULD BE CONTROLLED
THIS DETAIL IS A MINIMUM DESIGN AND MAY BE
MODIFIED DEPENDING UPON ENCOUNTERED
CONDITIONS AND LOCAL REQUIREMENTS
NOT TO SCALE
TYPICAL SUBDRAIN OUTLET HEADWALL DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 17 of 26
4" DIAMETER PERFORATED
PIPE BACKDRAIN
4" DIAMETER NON-PERFORATED
PIPE LATERAL DRAIN
15' MINIMUM
SLOPE PER PLAN
2.0%
FILTER MATERIAL - BENCHING
H12
t2IMi M - lEfli: I I-r-rrI I ITIr AN ADDITIONAL BACKDRAIN
AT MID-SLOPE WILL BE REQUIRED FOR
SLOPE IN EXCESS OF 40 FEET HIGH.
KEY-DIMENSION PER SOILS ENGINEER
(GENERALLY 1/2 SLOPE HEIGHT, 15' MINIMUM)
DIMENSIONS ARE MINIMUM RECOMMENDED
NOT TO SCALE
TYPICAL SLOPE STABILIZATION FILL DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 18 of 26
15' MINIMUM
4" DIAMETER PERFORATED
PIPE BACKDRAIN
4" DIAMETER NON-PERFORATED
PIPE LATERAL DRAIN - -
SLOPE PER PLAN
20% IH 1
FILTER MATERIAL = .1 BENCHING
1'
2'MI 2% MIN -HI
I II I Ii I I-i 1 17 -- iii ADDITIONAL BACKDRAIN AT
MID-SLOPE WILL BE REQUIRED
k FOR SLOPE IN EXCESS OF 40
FEET HIGH.
KEY-DIMENSION PER SOILS ENGINEER
DIMENSIONS ARE MINIMUM RECOMMENDED
NOT TO SCALE
TYPICAL BUTTRESS FILL DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 19 of 26
FINAL LIMIT OF DAYLIGHT
EXCAVATION LINE
FINISH PAD
OVEREXCAVATE 3'
AND REPLACE WITH
COMPACTED FILL
OVEREXCAVATE
20' MAXIMUM 2
COMPETENT BEDROCK
kTAIIl
2' MINIMUM\ \ L. TYPICAL BENCHING
OVERBURDEN \ \.._. LOCATION OF BACKDRAIN AND
(CREEP-PRONE) \ OUTLETS PER SOILS ENGINEER \ AND/OR ENGINEERING GEOLOGIST \ DURING GRADING. MINIMUM 2% \ FLOW GRADIENT TO DISCHARGE
\ LOCATION.
EQUIPMENT WIDTH (MINIMUM 15')
NOT TO SCALE
DAYLIGHT SHEAR KEY DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 20 of 26
NATURAL GROUND
PROPOSED GRADING
01
/ \ / / \- _i_/ /
II, / 15/
-,
1.5
ly
/
COMPACTED FILL
"WI'
_
PROVIDE BACKDRAIN, PER
BACKDRAIN DETAIL. AN
ADDITIONAL BACKDRAIN
AT MID-SLOPE WILL BE
REQUIRED FOR BACK
BASE WIDTH "W" DETERMINED SLOPES IN EXCESS OF
BY SOILS ENGINEER 40 FEET HIGH. LOCATIONS
OF BACKDRAINS AND OUTLETS
PER SOILS ENGINEER AND/OR
ENGINEERING GEOLOGIST
DURING GRADING. MINIMUM 2%
FLOW GRADIENT TO DISCHARGE
LOCATION.
NOT TO SCALE
TYPICAL SHEAR KEY DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 21 of 26
FINISH SURFACE SLOPE
3 FT3 MINIMUM PER LINEAR FOOT
APPROVED FILTER ROCK*
CONCRETE COLLAR
PLACED NEAT COMPACTED FILL
A
4" MINIMUM DIAMETER
SOLID OUTLET PIPE
SPACED PER SOIL
ENGINEER REQUIREMENTS
DURING GRADING TYPICAL
BENCHING
- 4" MINIMUM APPROVED
PERFORATED PIPE**
(PERFORATIONS DOWN)
MINIMUM 2% GRADIENT
TO OUTLET
BENCH INCLINED
TOWARD DRAIN
DETAIL A-A
TEMPORARY FILL LEVEL
MINIMUM MINIMUM 4N DIAMETER APPROVED
12" COVE
.L
[// SOLID OUTLET PIPE
ç
MINIMUM
*FILTER ROCK TO MEET FOLLOWING
**APPROVED PIPE TYPE: SPECIFICATIONS OR APPROVED EQUAL:
SCHEDULE 40 POLYVINYL CHLORIDE SIEVE SIZE PERCENTAGE PASSING (P.V.C.) OR APPROVED EQUAL. 1. 100
MINIMUM CRUSH STRENGTH 1000 PSI 90-100
40-100
NO.4 25-40
NO. 30 5-15
NO. 50 0-7
NO. 200 0-3
NOT TO SCALE
TYPICAL BACKDRAIN DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 22 of 26
FINISH SURFACE SLOPE
MINIMUM 3 FT PER LINEAR FOOT
OPEN GRADED AGGREGATE*
TAPE AND SEAL AT COVER
CONCRETE COLLAR
PLACED NEAT COMPACTED FILL
A
MINIMUM 4" DIAMETER
SOLID OUTLET PIPE
SPACED PER SOIL
ENGINEER REQUIREMENTS
TYPICAL
BENCHING
II '- MIRAFI 140N FABRIC OR
APPROVED EQUAL
4" MINIMUM APPROVED
PERFORATED PIPE
(PERFORATIONS DOWN)
MINIMUM 2% GRADIENT
TO OUTLET
BENCH INCLINED
TOWARD DRAIN
DETAIL A-A
TEMPORARY FILL LEVEL
MINIMUM
12" COVER BACKFILL MINIMUM 4" DIAMETER APPROVED
SOLID OUTLET PIPE
12"
*NOTE: AGGREGATE TO MEET FOLLOWING
SPECIFICATIONS OR APPROVED EQUAL:
SIEVE SIZE PERCENTAGE PASSING
100
1" 5-40
3/4k 0-17
0-7
NOT TO SCALE
NO. 200 0-3
BACKDRAIN DETAIL (GEOFRABIC)
STANDARD SPECIFICATIONS FOR GRADING
Page 23 of 26
FILL SLOPE
CLEAR ZONE —/
I xcccr
SOIL SHALL BE PUSHED OVER I EQUIPMENT WIDTH
ROCKS AND FLOODED INTO I / VOIDS. COMPACT AROUND
AND OVER
STACK BOULDERS END TO END.
DO NOT PILE UPON EACH OTHER.
'
10']
FILL SLOPE J,
10' MIN STAGGER
ROWS 15'
/
O,MPT
NOT TO SCALE
ROCK DISPOSAL DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 24 of 26
1
FINISHED GRADE BUILDING I
NO OVERSIZE, AREA FOR
10' FOUNDATION, UTILITIES,
SLOPE FACE AND SWIMMING POOLS
STREET 0
15'
WINDROW _J
5' MINIMUM OR BELOW
DEPTH OF DEEPEST
UTILITY TRENCH
(WHICHEVER GREATER)
TYPICAL WINDROW DETAIL (EDGE VIEW)
j- GRANULAR SOIL FLOODED
I TO FILL VOIDS
HORIZONTALLY PLACED
COMPACTION FILL
PROFILE VIEW
NOT TO SCALE
ROCK DISPOSAL DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 25 of 26
GENERAL GRADING RECOMMENDATIONS
CUT LOT
-ORIGINAL
GROUND -
TOPSOIL, COLLUVIUM AND
WEATHERED BEDROCK 5' MIN
3' MIN
OVEREXCAVATE
UNWEATHERED BEDROCK AND REGRADE
CUT/FILL LOT (TRANSITION)
ORIGINAL
.0101 .01
GROUND
-.-----.--
MIN
COMPACTED FILL 3' MIN
-.--- - TOPSOIL, COLLUVIUM
-AND WEATHERED
BEDROCK
.00
.00
-
0
UNWEATHERED BEDROCK
NOT TO SCALE
OVEREXCAVATE
AND REGRADE
TRANSITION LOT DETAIL
STANDARD SPECIFICATIONS FOR GRADING
Page 26 of 26