HomeMy WebLinkAboutCDP 15-20; LIMITED GEOTECHNICAL INVESTIGATION; 2016-01-07RCE 54071, GE 2704
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Mamadou Salicu iallo, P.E. LAND DEVELOPMENT
ENGINEERING
RECEIVED
AUG 15 2016
flECORD COPY
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Date, EAST COUNTY SOIL CONSULTATION
AND ENGINEERING, INC.
10925 HARTLEY ROAD, SUITE "I"
SANTEE, CALIFORNIA 92071
(619) 258-7901
Fax 258-7902
Bob & Monica Flora
2208 Eastbrook Road
Falibrook, California 92081
Subject: Limited Geotechnical Investigation
Proposed Residential Renovation
155 Walnut Avenue
City of Carlsbad, California 92008
Dear Mr. & Mrs. Flora:
January 7, 2016
Project No. 15-1106E6
In accordance with your request, we have performed a limited geotechnical investigation at the
subject site to discuss the geotechnical aspects of the project and provide recommendations for
t
h
e
proposed residential improvement.
Our investigation has found that the areas of the proposed improvement are underlain by topso
i
l
t
o
a depth of approximately 12 to 18 inches below existing grade. Dense terrace deposits wer
e
underlying the topsoil to the explored depth of 6 feet. It is our opinion that the proposed residential
renovation is geotechnically feasible provided the recommendations herein are implemented in the
design and construction.
Should you have any questions with regard to the contents of this report, please do not hesitate t
o
contact our office.
Respectfully submitted,
- r 4, us.4;
No. r-,E 2704
BOB &, MONICA FLORA/ WALNUTA VENUE PROJECT NO. /5-I/06E6
TABLE OF CONTENTS
INTRODUCTION..............................................................................................................................................3
SCOPEOF SERVICES ...................................................................................................................................... 3 SITE DESCRIPTION AND PROPOSED CONSTRUCTION .........................................................................3
FIELD INVESTIGATION AND LABORATORY TESTING........................................................................4
GEOLOGY.........................................................................................................................................................4
GeologicSetting ............................................................................................. ....................................... 4 SiteStratigraphy ........................................................ ............................................... . ............................ 4
SEISMICITY......................................................................................................................................................
5 RegionalSeismicity ............................................................................................................................... 5 SeismicAnalysis ...................................................................................................................................
5 2013 CBC Seismic Design Criteria ..................................................................................
....... ............. 6 GeologicHazard Assessment ............. . ............... ..................................................................... .............. 6
GEOTECHNICAL E VALUATION ............................................................................................. ..................... 7 CompressibleSoils................................................................................................................................
7 ExpansiveSoils......................................................................................................................................
7 Groundwater..........................................................................................................................................7
CONCLUSIONS AND RECOMMENDATIONS ............................................................................................ 8
CLEARINGAND GRUBBING ......... .... ............................ . ............................................................... . ................ 8 FOUNDATIONSAND SLABS ........................................................................................................................8
SETTLEMENT................................................................................................................. ....................................9 PRESATURATION OF SLAB SUBC'RADE ................................................................................................... 9
TEMPORARYSLOPES ...............................................................................
...................................................... 9 TRENCHBACKFILL ......................... .............................................................................................................. 9
DRAINAGE...................................................................................................................................................... 10
FOUNDATION PLAN REVIEW ..................................................................................................................... 10 LIMITATIONS OF INVESTIGATION .........................................................................................................10
ADDITIONALSERVICES ............................................................................................................................II
PLATES
Plate I - Location of Exploratory Boreholes
Plate 2 - Summary Sheet (Exploratory Borehole Logs)
Plate 3,- USCS Soil Classification Chart
PAGE L- I, LABORATORY TEST RESULTS ..................................................
............................................. 13
REFERENCES.................................................................................................................................................14
7
BOB & MONICA FLORA! WALNUTA VENUE PROJECT NO. 15-I106E6
INTRODUCTION
This is to present the findings and conclusions of a limited geotechnical investigation for the
proposed renovation of the existing single-family residence located at 155 Walnut Avenue, in the City of Carlsbad, California.
The objectives of the investigation were to evaluate the existing soils conditions and provi
d
e
recommendations for the proposed improvement.
SCOPE OF SERVICES
The following services were provided during this investigation:
0 Site reconnaissance and review of published geologic, seismological and geotechnical reports
and maps pertinent to the project area
0 Subsurface exploration consisting of three (3) boreholes within the limits of the proposed areas of improvement. The boreholes were logged by our Staff Geologist.
0 Collection of representative soil samples at selected depths. The obtained samples were sealed
in moisture-resistant containers and transported to the laboratory for subsequent analysis.
0 Laboratory testing of samples representative of the types of soils encountered during the field
investigation
0 Geologic and engineering analysis of the field and laboratory data, which provided the basis
for our conclusions and recommendations
0 Production of this report, which summarizes the results of the above analysis and presents our
findings and recommendations for the proposed improvement
SITE DESCRIPTION AND PROPOSED CONSTRUCTION
The subject site is a rectangular-shaped residential lot located on the south side of Walnut Avenue,
in the City of Carlsbad, California. The property which encompasses an area of 4,375 square feet (87.5' X 50') includes a one-story residence with a detached parking canopy and a storage room.
The building pad is relatively level with general drainage to the west. Vegetation consisted of
grass, shrub and a few trees. Site boundaries include Walnut Avenue to the north and similar
residential developments to the remaining directions.
The preliminary plans prepared by Wright Design of Carlsbad, California indicate that the
proposed renovation will include a second-story and deck addition to the existing, one-story single-
family residence and a detached garage with a living unit above, following demolition of the
existing parking canopy and storage room. It is our understanding that the structures will be wood-
framed and founded on continuous and/ or spread footings with a slab-on-grade floor.
BOB & MONICA FLORA! WALNUT A VENUE PROJECT NO. 15-1106E6
FIELD INVESTIGATION AND LABORATORY TESTING
On December 10, 2015. three (3) boreholes were excavated to a maximum depth of approx
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6 feet below existing grade with a hand auger. The approximate locations of the bor
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shown on the attached Plate No. 1, entitled "Location of Exploratory Boreholes". A co
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of the soils encountered was recorded at the time of excavation and is shown on Plat
e
N
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2
e
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"Summary Sheet". The soils were visually and texturally classified accor
d
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f
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d
identification procedures set forth on Plate No. 3 entitled "USCS Soil Classification".
Following the field exploration, laboratory testing was performed to eval
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p
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engineering properties of the foundation materials. The laboratory-testing progra
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e
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moisture and density, particle size analysis and expansion index tests. These tests wer
e
p
e
r
f
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m
e
d
in general accordance with ASTM standards and other accepted methods. Page L- I an
d
P
l
a
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e
N
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.
2
provide a summary of the laboratory test results.
GEOLOGY
Geologic Setting
The subject site is located within the southern portion of what is known as the Peni
n
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r
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Geomorphic Province of California. The geologic map pertaining to the area (Refe
r
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n
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e
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.
7
)
indicates that the site is underlain by Pleistocene terrace deposits (Qt).
Site Stratigraphy
The subsurface descriptions provided are interpreted from conditions expose
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investigation and/or inferred from the geologic literature. Detailed descriptions
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f
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s
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b
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materials encountered during the field investigation are presented on the exploration lo
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Plate No. 2. The following paragraphs provide general descriptions of the encounter
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d
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y
p
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.
Topsoil
Topsoil is the surficial soil material that mantles the ground, usually containing root
s
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r
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materials, which supports vegetation. Topsoil was observed in the boreholes wit
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approximately 12 to 18 inches. It consisted of dark brown, silty sand that was moist, loos
e
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p
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in consistency with some organics (roots and rootlets).
Terrace Deposits (Ot)
Terrace deposits were encountered below the topsoil layer. They generally con
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brown, silty sand that was moist and medium dense to dense in consistency.
11
BOB & MONICA FLORA/ WALNUTA VENUE PROJECT NO. 15-I 106E6
SEISMICITY
Regional Seismicity
Generally, Seismicity within California can be attributed to the regional tectonic mo
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t
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place along the San Andreas Fault Zone, which includes the San Andreas Fault and
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and subparallel faults within the state. The portion of southern California where the
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located is considered seismically active. Seismic hazards are attributed to grou
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h
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k
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o
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earthquake events along nearby or more distant Quaternary faults. The pri
m
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f
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s
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evaluating the effect an earthquake has on a site are the magnitude of the event,
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d
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the epicenter to the site and the near surface soil profile.
According to the Fault-Rupture Hazard Zones Act of 1994 (revised Alquist-Priol
o
S
p
e
c
i
a
l
S
t
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d
i
e
s
Zones Act), quaternary faults have been classified as "active" faults, which s
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p
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rupture during the last 11,000 years (i.e., Holocene time). "Potentially-active" faults
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s
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f
a
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l
t
s
with evidence of displacing Quaternary sediments between 11,000 to 16,000 years ol
d
.
Seismic Analysis
Based on our evaluation, the closest known "active" fault is the Newport-Ingl
e
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approximately 7.4 kilometers (4.6 miles) to the west. The Newport-Jnglewood Fault is
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of the project due to the predicted credible fault magnitude and ground acceleration.
The Seismicity of the site was evaluated utilizing the 2008 National Hazard M
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p
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m
t
h
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U
S
G
S
website and Seed and Idriss methods for active Quaternary faults within the r
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g
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n
a
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v
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.
T
h
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site may be subjected to a Maximum Probable Earthquake of 7.2 Magnitude
a
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N
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t
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Inglewood Fault, with a corresponding Peak Ground Acceleration of 0.45g.
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Probable Earthquake is defined as the maximum earthquake that is considered
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within a 100-year time period.
The effective ground acceleration at the site is associated with the part of si
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motion, which contains repetitive strong-energy shaking, and which may prod
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deformation. As such, the effective or "free field" ground acceleration is refe
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Repeatable High Ground Acceleration (RHGA). It has been determined by P
l
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e
s
s
e
l
a
n
d
S
l
o
s
s
o
n
(1974) that the RHGA is approximately equal to 65 percent of the Peak Ground
A
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earthquakes occurring within 20 miles of a site. Based on the above, the calcul
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C
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RHGA at the site is 0.29g.
BOB & MONICA FLORA! WALNUT A VENUE PROJECT NO. 15-1106E6
2013 CBC Seismic Design Criteria
A review of the active fault maps pertaining to the site indicates the location of the Newport-
Inglewood Fault Zone approximately 7.4 km to the west. Ground shaking from this fault or one of
the major active faults in the region is the most likely happening to affect the site. With respect to
this hazard, the site is comparable to others in the general area. The proposed residential
renovation, should be designed in accordance with seismic design requirements of the 2013
California Building Code or the Structural Engineers Association of California using the following
seismic design parameters:
PARAMETER
- VALUE 2013 CBC & ASCE 7 REFERENCES Site Class D Table 20.3-1/ ASCE 7, Chapter 20 Mapped Spectral Acceleration For Short Periods,
Ss
1 .161 g Figure 1613.3.1(1)
Mapped Spectral Acceleration For a 1-Second
Period, S1
0.445g Figure 1613.3.1(2)
Site Coefficient, Fa 1.035 Table 1613.3.3(1) Site Coefficien, F 1.555 Table 16133 ).3(2) Adjusted Max. Considered Earthquake Spectral
Response Acceleration for Short Periods, SMS
1.203g Equation 16-37
Adjusted Max. Considered Earthquake Spectral
Response Acceleration for 1-Second Period, SMI
0.692g Equation 16-38
5 Percent Damped Design Spectral Response
Acceleration for Short Periods, S0
0.802g Equation 16-39
5 Percent Damped Design Spectral Response
Acceleration for 1-Second Period, S01
0.4619 Equation 16-40
Geologic Hazard Assessment
Ground Rupture
Ground rupture c'ue to active faulting is not considered likely due to the absence of known fault traces
within the vicinity of the project; however, this possibility cannot be completely ruled out. The
unlikely hazard of ground rupture should not preclude consideration of "flexible" design for on-site
utility lines and connections.
Liquefaction
Liquefaction involves the substantial loss of shear strength in saturated soils, usually sandy soils with a
loose consistency when subjected to earthquake shaking. Based on the absence of shallow
groundwater and consistency of the underlying terrace deposits, it is our opinion that the potential for
liquefaction is very low.
Landsliding
There is no indication that landslides or unstable slope conditions exist on or adjacent to the project
site. There are no obvious geologic hazards related to landsliding to the proposed improvement or
adjacent properties.
BOB & MON/CA FLORA! WALNUTA VENUE PROJECT NO. 15-1106E6
Tsunamis and Seiches
The site is not subject to inundation by tsunamis due to its elevation. The site is also not subject to
seiches (waves in confined bodies of water).
GEOTECHNICAL EVALUATION
Based on our investigation and evaluation of the collected information, we conclude that the
construction of the proposed additions is feasible from a geotechnical standpoint provided the
recommendations herein will be properly implemented during construction.
In order to provide a uniform support for the proposed additions, footings should be embedded into the
dense terrace deposits. However, for slab support for the proposed detached garage/ living unit,
overexcavation and recompaction of the upper 18 inches of subgrade will be required. The
foundations may consist of reinforced continuous or spread footings with reinforced slabs.
Recommendations and criteria for foundation design are provided in the Foundation and Slab
recommendations section of this report.
Compressible Soils
Our field observations and testing indicate low compressibility within the terrace deposits, which
underlie the areas of the proposed additions. However, loose topsoil was encountered to a maximum
depth of approximately 18 inches below surface grades. These soils are compressible, therefore not
adequate for the support of the proposed additions. As a result, footings for the proposed additions
should be extended to the dense terrace deposits.
Following implementation of the recommendations presented herein, the potential for soil
compression resulting from the new development has been estimated to be low. The low-settlement
assessment assumes a well-planned and maintained site drainage system.
Expansive Soils
An expansion index test was performed on a representative sample of the terrace deposits to
determine volumetric change characteristics with change in moisture content. An expansion index
of 0 was obtained which indicates a very low expansion potential for the foundation soils.
Groundwater
Static groundwater was not encountered to the depths of the boreholes. The building pad is located
at an elevation of approximately 50 feet above Mean Sea Level. We do not expect groundwater to
affect the proposed construction. Recommendations, to prevent or mitigate the effects of poor
surface drainage are presented in the Drainage section of this report.
7
BOB & MONICA FLORA! WALNUT AVENUE PROJECTNO. I5-1/06E6
CONCLUSIONS AND RECOMMENDATIONS
The following conclusions and recommendations are based upon the analysis of the data a
n
d
information obtained from our soil investigation. This includes site reconnaissance; fi
e
l
d
investigation; laboratory testing and our general knowledge of the soils native to the site. The
s
i
t
e
is suitable for the proposed residential additions provided the recommendations set forth are
implemented during construction.
CLEARING AND GRUBBING
The area of the proposed garage should be cleared of vegetation. Vegetation and debris from the
clearing operation should be properly disposed of off-site. The area should be thor
o
u
g
h
l
y
inspected for any possible buried objects, which need to be rerouted or removed pr
i
o
r
t
o
construction. All holes, trenches, or pockets left by the removal of these objects should be pro
p
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l
y
backfihled with compacted fill materials.
FOUNDATIONS AND SLABS
Continuous and spread footings are suitable for use and should extend to a minimum depth of 18
inches for the proposed two-story structures into the dense terrace deposits. Continuous foo
t
i
n
g
s
should be at least 15 inches in width and reinforced with a minimum of four #4 steel bars; two
b
a
r
s
placed near the top of the footings and the other two bars placed near the bottom of the foo
t
i
n
g
s
.
Isolated or spread footings should have a minimum width of 24 inches. Their reinforcement sho
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l
d
consist of a minimum of 44 bars spaced 12 inches on center (each way) and placed horizontall
y
near the bottom. New footings should be dowelled to existing footings in accordance with th
e
structural engineer requirements. The minimum reinforcement recommended is based on soil
characteristics and is not intended to supersede the structural engineer requirements.
Interior concrete floor slabs should be a minimum 4 inches thick. Reinforcement should con
s
i
s
t
of #3 bars placed at 18 inches on center each way within the middle third of the slabs by supporti
n
g
the steel on chairs or concrete blocks ftdobiesH. The slabs should be underlain by 2 inches of clean sand over a I 0-mil visqueen moisture barrier. The effect of concrete shrinkage will result in cracks
in virtually all-concrete slabs. To reduce the extent of shrinkage, the concrete should be placed at a
maximum of 4-inch slump. The minimum steel recommended is not intended to prevent shrinkag
e
cracks.
Where moisture sensitive floor coverings are anticipated over the slabs, the 10-mil plasti
c
moisture barrier should be underlain by a capillary break at least 2 inches thick, consisting of
coarse sand, gravel or crushed rock not exceeding 3/4 inch in size with no more than 5 percent
passing the #200 sieve.
8
130/3 & MONICA FLORA! WALNUT VENUE PROJECT NO. 15-]106E6
An allowable soil bearing value of 2,000 pounds per square foot may be used for the design of
continuous and spread footings at least 12 inches wide and founded a minimum of 12 inches into
the dense terrace deposits as set forth in the 2013 California Building Code, Table 1804.2. This
value may be increased by 400 psf for each additional foot of depth or width to a maximum value
of 4,000 lblft2.
Lateral resistance to horizontal movement may be provided by the soil passive pressure and the
friction of concrete to soil. An allowable passive pressure of 300 pounds per square foot per foot
of depth may be used. A coefficient of friction of 0.35 is recommended. The soils passive pressure
as well as the bearing value may be increased by 1/3 for wind and seismic loading.
SETTLEMENT
Since the proposed footings are anticipated to be supported by the dense terrace deposits, the total and
differential settlement should be within tolerable limits.
PRESATURATION OF SLAB SUBGRADE
Because of the granular characteristics of on-site soils, presoaking of subgrade prior to concrete
pour is not required. However, subgrade soils in areas receiving concrete should be watered prior
to concrete placement to mitigate any drying shrinkage, which may occur following foundation
excavation.
TEMPORARY SLOPES
For the excavation of foundations and utility trenches, temporary vertical cuts to a maximum height of
4 feet may be constructed in fill or natural soil. Any temporary cuts beyond the above height
constraints should be shored or further laid back following a 1:1 (horizontal to vertical) slope ratio..
OSHA guidelines for trench excavation safety should be implemented during construction.
TRENCH BACKFILL
Excavations for utility lines, which extend under structural areas should be properly backfihled and
compacted. Utiiities should be bedded and backfilled with clean sand or approved granular soil to
a depth of at least one foot over the pipe. This backfill should be uniformly watered and
compacted to a firm condition for pipe support. The remainder of the backfill should be on-site
soils or non-expansive imported soils, which should be placed in thin lifts, moisture-conditioned
and compacted to at least 90% relative compaction.
BOB &, MONICA FLORA/ WALNUTA VENUE PROJECT NO. 15-/106E6
DRAINAGE
Adequate measures should be undertaken after the additions and other improvements are in place,
such that the drainage water within the site and adjacent properties is directed away from t
h
e
foundations, footings, floor slabs and the tops of slopes via rain gutters, downspouts, surface swales
and subsurface drains towards the natural drainage for this area. A minimum gradient of 2 percent
is recommended in hardscape areas In earth areas, a minimum gradient of 5 percent away from the structures for a distance of at least 10 feet should be provided. Earth swalës should hav
e
a
minimum gradient of 2 percent. Drainage should be directed to approved drainage facilities.
Proper surface and subsurface drainage will be required to minimize the potential of water seeking
the level of the bearing soils under the foundations, footings and floor slabs, which may otherw
i
s
e
result in undermining and differential settlement of the structures and other improvements.
FOUNDATION PLAN REVIEW
Our firm should review the foundation plans during the design phase to assure conformance with the
intent of this report. During construction, foundation excavations should be observed by o
u
r
representative prior to the placement of forms, reinforcement or concrete for conformance with t
h
e
plans and specifications.
LIMITATIONS OF INVESTIGATION
Our investigation was performed using the skill and degree of care ordinarily exercised, under similar
circumstances, by reputable soils engineers and geologists practicing in this or similar localities. No
other warranty, expressed or implied, is made as to the conclusions and professional advice inclu
d
e
d
i
n
this report. This report is prepared for the sole use of our client and may not be assigned to
o
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h
e
r
s
without the written consent of the client and ECSC&E, Inc.
The samples collected and used for testing, and the observations made, are believed representat
i
v
e
o
f
site conditions; however, soil and geologic conditions can vary significantly between explora
t
i
o
n
trenches, boreholes and surface exposures. As in most major projects, conditions revealed
b
y
construction excavations may vary with preliminary findings. If this occurs, the changed conditions
must be evaluated by a representative of ECSC&E and designs adjusted as required or alternate
designs recommended.
This report is issued with the understanding that it is the responsibility of the owner, or of his
representative to ensure that the information and recommendations contained herein are brought to the
attention of the project architect and engineer. Appropriate recommendations should be incorporated
into the structural plans. The necessary steps should be taken to see that the contractor
a
n
d
subcontractors carry out such recommendations in the field.
IN
BOB & MON/CA FLORA! WALNUT A VENUE PROJECT NO. 15-1/06E6
The findings of this report are valid as of this present date. However, changes in the
c
o
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d
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t
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s
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f
a
property can occur with the passage of time, whether they are due to natural processe
s
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r
t
h
e
w
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r
k
s
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f
man on this or adjacent properties. In addition, changes in applicable or appropr
i
a
t
e
s
t
a
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d
a
r
d
s
m
a
y
occur from legislation or the broadening of knowledge. Accordingly, the findin
g
s
o
f
t
h
i
's report may be invalidated wholly or partially by changes outside of our control. Therefore, t
h
i
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e
p
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t
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review and should be updated after a period of two years.
ADDITIONAL SERVICES
The review of plans and specifications, field observations and testing under our di
r
e
c
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a
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parts of the recommendations made in this report. If East County Soil Consultati
o
n
a
n
d
E
n
g
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n
e
e
r
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,
Inc. is not retained for these services, the client agrees to assume our responsibility f
o
r
a
n
y
p
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t
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t
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claims that may arise during construction. Observation and testing are additional servi
c
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s
,
w
h
i
c
h
a
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provided by our firm, and should be budgeted within the cost of development.
Plates No. I through 3, Page L-1 and References are parts of this report.
fl<W?1
EAST COUNTY SOIL CONSULTATION
& ENGINEERING, INC. / 0925 HARTLEY RD., surr I, SANTEE. CA 92071
(619) 25-7901 Fax (619) 258.7902 ew
-
BOB & MONICA FLORA/ WALNUTA VENUE PROJECT NO. 15-1106E6
PLATE NO.2
SUMMARY SHEET
BOREHOLE NO. I
DEPTH SOIL DESCRIPTION
Surface TOPSOIL
dark brown, moist, loose, porous, silty sand with rootlets
LU' TERRACE DEPOSITS (Qt)
reddish brown, moist, medium dense, silty sand
3.0' 44 4L 16 41
4.0' becomes dense
6.0' bottom of borehOle, no caving, no groundwater
borehole backfilled 12/10/15
BOREHOLE NO.2
DEPTH SOIL DESCRIPTION
Surface TOPSOIL
dark brown, moist, loose, porous, silty sand with rootlets
1.5' TERRACE DEPOSITS (Qt)
reddish brown, moist, medium dense, silty sand
3.0' becomes dense
5.0' bottom of borehole, no raving, no groundwater
borehole backfilled 12/10/I5
BOREHOLE NO.3
DEPTH SOIL DESCRIPTION
Surface TOPSOIL
dark brown, moist, loose, porous, silty sand with rootlets
1.0' TERRACE DEPOSITS (Qt)
reddish brown, moist, medium dense, silty sand
becomes dense
4.0' bottom of borehole, no caving, no groundwater
borehole backfilled 12/10/15
Y M
111.7 7.3
109.4 7.9
7.5
6.7
Y M
8.3
Y M
Y = DRY DENSITY IN PCF M = MOISTURE CONTENT IN %
12
CLASSIFICATION RANGE OF GRAIN SIZES
U.S. STANDARD I GRAIN SIZE IN SIEVE SIZE i MILLIMETERS BOULDERS Above 12 Inches Above 305 COBBLES 12 Inches To 3 Inches 305 To 76.2 GRAVEL 3 Inches to No.4 762 to 4.76 Coarse 3 Inches to '/. Inch 76.2 to 19.1 Fine 3A Inch to No. 4 19.1 to 4.76 SAND No.4 to No. 200 4.76 to 0.074 Coarse No. 4 to No. 10 4.76 to 2.00 Medium No. 10 to No. 40 2.00 to 0.420 Fine No. 40 to No. 200 0.420 to 0.074 SILT AND CLAY Below No. 200 - Below 0.074
'ZLZ1 VL I zL-2 .7 0
I + PI-0.73 Lk-m -P1
ML'OL
I.'UO L 14. y I.I.i ,.
MAJOR DIVISIONS SYMBOL DESCRIPTION
Gw
WELL GRADED GRAVELS OR GRAVEL- SAND
MIXTURES, LITTLE OR NO FINES
GP
_________
POORLY GRADED GRAVELS OR GRAVEL-SAND
MIXTURES, LITTLE OR NO FINES
GRAVELS
(MORE THAN
OF COARSE
FRACTION
>NO. 4 SIEVE
GM
SILTY GRAVELS, GRAVEL-SAND-SILT MIXTURES
COARSE
GRAINED SOILS
SIZE)
GC CLAYEY GRAVELS, GRAVEL-SAND-CLAY MIXTURES
(MORE THAN OF SOIL
> NO. 20C SIEVE SIZE) sw
WELL GRADED SANDS OR GRAVELLY SANDS,
LITTLE ORNOFINES
SP
POORLY GRADED SANDS OR GRAVELLY SANDS,
LITTLE OR NO FINES
SANDS
(MORE ThAN
OF COARSE
FRACTION
< NO. 4 SIEVE
_________
SM
SILTY SANDS, SILT-SAND MIXTURES
SIZE)
-. SC
CLAYEY SANDS, SAND-CLAY MIXTURES
SILTS &
ML INORGANIC SILTS AND VERY FINE SANDS, ROCK
FLOUR, SILTY OR CLAYEY FINE SANDS OR CLAYEY SILTS WITH SLIGHT PLASTICITY
FINE GRAINED
SOILS
(MORE fl-IAN OF SOIL <NO. 200 SIEVE SIZE)
CLAYS
LIQUID LIMIT
<50
_________
CL
__________
INORGANIC CLAYS OF LOW TO MEDIUM
PLASTICITY, GRAVELLY CLAYS, SANDY CLAYS,
SILTY CLAYS, LEAN CLAYS
OL
_________
ORGANIC SILTS AND ORGANIC SILTY CLAYS OF
LOW PLASTICITY
SILTS &
MH
INORGANIC SILTS, MICACEOUS OR DIATOMACEOUS
FINE SANDY OR. SILTY SOILS, ELASTIC SILTS
CH INORGANIC CLAYS OF HIGH PLASTICITY, FAT
CLAYS
CLAYS
LIQUID LMT
> 50
OH
ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY,
ORGANIC SILTY CLAYS, ORGANIC SILTS HIGHLY ORGANIC SOILS Pt
PEAT AND OTHER HIGHLY ORGANIC SOILS
CLASSIFICATION CHART (UNIFIED SOIL CLASSIFICATION SYSTE
M
)
GRAIN SIZE CHART PLASTICITY CHART
EAST COUNTY SOIL CONSULTATION
AND ENGINEERING, INC. 10925 HARTLEY ROAD, SUITE "I" ft- ,. SANTEE, CALIFORNIA 92071 fro.
JSCS. SOIL CLASSIFICATION
BOB & MONICA FLORA! WALNUT A VENUE PROJECTNO. 15-II06E6
PACE L-I
LABORATORY TEST RESULTS
EXPANSION INDEX TEST (ASTM D4829)
INITIAL SATURATED INITIAL DRY MOISTURE MOISTURE DENSITY EXPANSION CONTENT(%) CONTENT(%' (PCF) INDEX LOCATION
9.1 17.8 109.6 0 BH-2@ 1.5'
PARTICLE SIZE ANALYSIS (ASTM 0422)
I .S. Stand,rd icnt Pass;n Percent Pasing Percent Passing cen Pert Passing S l. e Si i RU-I a 0 13112 a 1 ' W-I I 4 0 BH lODSOjI I TITa DcrLsits. TéaceI)eDosit Terrióe DenOsits
1/2"
3/8" 10
#4 99 - - - #8 98 - - - #16 96 100 100 100 430 82 87 88 90 #50 42 45 43 40 #100 21 25 21 IS 4200 16 21 16 12
USCS I SM I SM I SM I SM i
BOB & MONICA FLORAl WALNUT A VENUE PROJECT NO. 15-1/06E6
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