HomeMy WebLinkAboutCT 07-05; LA COSTA GREENS NEIGHBORHOOD 1.03; FINAL REPORT OF TESTING & OBSERVATION SERVICES DURING SITE GRADING; 2009-05-12P CR
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FINAL REPORT OF TESTING
AND OBSERVATIONSERVICES
PERFORMED DURING SITE GRADING
VILLAGES OF LA COSTA
THE GREENS
NEIGHBORHOOD 1.03
LOTS 1 THROUGH .8.
CARLSBAD1 CALIFORNIA
PREPARED FOR
COLRICH
SAN DIEGO, CALIFORNIA
MAY 12, 2009
PROJECT NO 06403-52-32A
GEOCON
INCORPORATED
GEOTECHNICAL CONSULTANTS 0
Project No. 06403-52-32A
May 12, 2009
(.
CoiRich .
4747 Morena Boulevard, Suite .100
San Diego, California 92117
Attention: Ms. Teri Shusterman
Subject: VILLAGES OF LA COSTA - THE GREENS
NEIGHBORHOODS 1.03
LOTS 1 THROUGH 38
CARLSBAD, CALIFORNIA
FINAL REPORT OF TESTING AND OBSERVATION SERVICES
PERFORMED DURING SITE GRADING
Dear Ms. Shusterman:
In accordance with your request and our Proposal No. LG-08212' dated June 25, 2008, we. have
provided testing and observation services during the, precise grading operations for Lots 1 through 38
within the Villages of La Costa; The Greens, Neighborhood 1.03 development. We performed our
services during the period of December 3, 2008 through May 7, 2009. The scope of our services
summarized in this report includes:
Observing removal excavations during remedial grading operations, performing field mapping,
and providing geotechnical engineering consultation services;
Observing the grading operations, including the removal and/or processing of topsoil,
undocumented fill, previously placed fill, alluvium, and, undercutting cut lots and cut/fill
transition lots.
Performing in-place density tests on fill placed and compacted at the site;
Performing laboratory tests to aid in evaluating the maximum dry density and optimum
moisture content and shear strength of the compacted fill. Additionally, we performed
laboratory tests on samples of soil present within approximately 3 feet of finish grade to
evaluate expansion characteristics, pH, resistivity, and water-soluble sulfate content;
Preparing a final As-Graded Geologic Map; and
Peparing this final report of grading
6960 Flanders Drive 0 San Diego, California 92121-2974 0 Telephone (858) 558-6900 M. Fox (858)558-6159
The site was previously sheet graded as part of the Villages of La Costa - The Greens, Neighborhoods
1.01 through 1.03 development. The property is located southeast of the intersection of El Camino Real
and Camino Vida Roble in Carlsbad, California. The Vicinity Map, Figure 1, shows the approximate
location of the site.
The grading contract-or for the project is American Pride Incorporated of Escondido, California. Grading
plans for the project are entitled Rough Grading Plans for: La Costa Greens, Neighborhood 1.3, prepared
by Hunsaker and Associates, with City of Carlsbad approval dated November 7, 2008.
The scope of our services also included a review of:
Addendum to Final Report of Testing and Observation Services Performed During Site
Grading, Villages of La Costa - The Greens, Neighborhoods 1.02 and 1.03, Carlsbad;
California, prepared by Geocon Incorporated, dated January 3, 2007 (Project No. 06403-
52-22):
1 Final Report of Testing and Observation Services Performed During Site Grading, Villages of
La Costa - The Greens, Neighborhoods 1.02 and 1.03, Carlsbad, California, prepared by
Geocon Incorporated, dated April 3, 2006 (Project No. 06403-52-22).
Update Soil and Geological Investigation, Volume land It, Villages of La Costa - The Greens,
Carlsbad, California, prepared by Geocon Incorporated, dated June 25, 2001 (Project
No. 06403-12-03).
References to elevations and locations herein were based on surveyors' or grade checkers' stakes in the
field and interpolation from the referenced plans. Geocon Incorporated did not provide surveying
services and, therefore, has no opinion regarding the accuracy of the elevations or surface geometry
with respect to the approved plans.
GRADING
Prior to mass grading operations, the site was primarily characterized by moderately sloping hillside
terrain dissected by a series of tributary canyons that drained eastward toward San Marcos Creek. Mass
grading for the site consisted of daylight cuts and fills to achieve finish-grade elevations. We
performed testing and observations services during mass grading operations for the master developer.
A summary of the observations, compaction test results and professional opinions pertaining to the
mass grading operations are presented in the referenced reports dated April 3, 2006 and January 3,
2007. Subsequent to mass grading, the site consisted of a large sheet-graded pad with drainage
generally flowing to the southwest toward a desilting basin.
Project No. 06403-52-32A -2- May 12, 2009
This report pertains to the fine grading of Lots 1 through 38 within the Neighborhood 1.03
development. The grading operations for the site consisted of minor cut and fill operations to create 38
single-family residential buildings with associated infrastructure Grading began with the removal and
export of brush and vegetation from the area to be graded. Previously placed fill was scarified,
moisture conditioned as necessary, and compacted. Fill materials derived from onsite excavations and
imported material, were then placed and compacted in layers until the design elevations were attained.
In addition, due to the existence of cut/fill transitions and/or the difficult excavation characteristics of
the formational materials, cut and cut/fill transition lots were undercut at least approximately three feet
and replaced with compacted fill to the design elevations (map symbol Quc). The resulting removal
bottoms were sloped toward the adjacent streets or deeper fill. Bottom elevations and the approximate
. limits of the as-graded geology are presented on the As-Graded Geologic Map (Figure 2).
The existing ascending slope located adjacent to lots 27 through 31 and south of the terminus of Trona
Way was regraded during the recent grading operations. Minor amounts of cut and fill were placed to
achieve a slope inclination of at least 2:1 (horizontal:vertical). The approximate limits of the slope
regrading operations are presented on Figure 2.
Fill Materials and Placement Procedures
On-site and imported fill materials generally consist of silty to clayey sand. We observed compaction
procedures during grading operations and performed in-place density tests to evaluate the dry density
and moisture content of the fill soil. We performed in-place density tests in general conformance with
ASTM Test Method D 2922 (nuclear). The results of the in-place density tests are summarized on
Table I. In general, the in-place density test results indicate that the fill soil has a dry density of at least
90 percent of the laboratory maximum dry density near to slightly above optimum moisture content at
the locations tested. The approximate locations of the in-place density tests are shown on the As-
Graded Geologic Map (Figure 2).
We tested samples of material used for fill to evaluate moisture-density relationships, optimum
moisture content and maximum dry density (ASTM D 1557) and direct shear tests (ASTM D 3080) on
samples used within fill slopes. We tested samples within the upper 3 feet of finish grade to evaluate
the expansion index (ASTM D 4829), water-soluble sulfate 'content (California Test No. 417), andpH
and resistivity (California Test No. 643). The results of the laboratory tests are summarized on
Tables II through VI.
Slopes
The project slopes consist of fill slopes constructed at inclinations of 2:1 (horizontal: vertical) or flatter
with maximum heights of approximately 5 and 15 feet, respectively. Slopes should be planted, drained,
Project No. 06403-52-32A -3- May 12, 2009
and maintained to reduce erosion. Slope irrigation should be kept to a minimum to just support the
vegetative cover. Surface drainage should not be allowed to flow over the top of slops.
SOIL AND GEOLOGIC CONDITIONS
The soil and geologic conditions encountered during the. grading operations are similar to those
described in the referenced geotechnical reports. The Santiago Formation (Ts) was exposed in pad
undercuts and cut areas within street right-of-ways. Undocumented fill (Qudf) associated with an
access road is located in the central portion of the site. Grading in this vicinity was limited due to the
presence of the existing utility lines. The undocumented fill is located within the private roadway and
is not expected to adversely impact the project. Compacted flu, was placed in areas designated as Qcf
on Figure 2. In addition, compacted fill placed in undercut areas is designated as Quc. Table VII
presents a summary of As-Graded Building Pad Conditions for the building pads.
) The As-Graded Geologic Map, Figure 2, depicts the general geologic conditions observed. No soil or
geologic conditions were observed during grading that would preclude the continued development of
the property as planned.
CONCLUSIONS AND RECOMMENDATIONS
1.0 General
1.1 The grading has been performed in conformance with the recommendations of the previously
referenced project soils report by Geocon Incorporated and the geotechnical requirements of
the grading plans. Soil and geologic conditions encountered during grading that differ from
those expected in the project soils report are not uncommon. Where such conditions required
a significant modification to the recommendations of the project soils report, they have been
described herein. .
1.2 ' We did not observe soil or geologic conditions during grading that would preclude the
continued development of the property as planned. Based on laboratory test results and field
observations, it is the opinion of Geocon Incorporated that the fill observed and tested as part
of the grading for this project was generally compacted to a dry density of at least 90 percent
of the laboratory maximum dry density near to slightly above optimum moisture content.
1.3 The site is underlain by compacted fill and formational materials consisting of the Santiago
Formation. We observed the placement of compacted fill during grading operations and
performed in-place density tests to evaluate the dry density and moisture content of the fill soil.
t
Project No. 06403-52-32A . . -4 - May 12, 2009
1.4 Laboratory testing of near-grade soil conditions indicates that the upper approximately 3 feet
of soil underlying the pads possess a "very low" to "medium" expansion potential
(expansion index of 90 or less). In addition, the samples indicate the soil possesses
"moderate" to "severe" water-soluble sulfate content.
1.5 The site is considered suitable for the use of conventional foundations with slabs-on-grade,
and/or post-tensioned foundation systems or on post-tensioned mat slabs. Foundation
categories for the subject lots are presented in Table VII. -
1.6 Excavations within the fill and formational materials should generally be possible with
moderate to heavy effort using conventional heavy-duty equipment.
2.0 Finish Grade Soil Conditions
2.1 Observations and laboratory test results indicate that the prevailing soil conditions within the
upper approximately 3 feet of finish grade is considered to be "expansive" (expansion index
[El] of greater than 20) as defined by 2007 California Building Code (CBC)
Section 1802.3.2. Table 2.1 presents soil classifications based on the expansion index.
Results of the El laboratory tests are presented in Table IV. Based on our laboratory testing,
the on-site soil possesses a "very low" to "medium" expansion potential (expansion index of
90 or less).
TABLE 2.1
SOIL CLASSIFICATION BASED ON EXPANSION INDEX
Expansion Index (El) Soil Classification
0-20 Very Low
21-50 Low
51-90 Medium
91-130 High
Greater Than 130 Very High
2.2 We performed laboratory tests on samples of the site materials to evaluate the percentage of
water-soluble sulfate content. Results from the laboratory water-soluble sulfate content tests
are presented in Table V and indicate that the on-site materials at the locations tested possess
"moderate" to "severe" sulfate exposure to concrete structures as defined by 2007 CBC
Section 1904.3 and ACI 318. Table 2.2 presents a summary of concrete requirements set
forth by 2007 CBC Section 1904.3 and ACI 318. The presence of water-soluble sulfates is
not a visually discernible characteristic; therefore, other soil samples from the site could
Project No. 06403-52-32A -5 - May 12, 2009
yield different concentrations. Additionally, over time landscaping activities (i.e., addition of
fertilizers and other soil nutrients) may affect the concentration.
TABLE 2.2
REQUIREMENTS FOR CONCRETE EXPOSED TO SULFATE-CONTAINING SOLUTIONS
Sulfate Water-Soluble Cement Maximum Water Minimum
Exposure Sulfate Percent Type to Cement Ratio . Compressive
by Weight by Weight Strength (psi)
Negligible 0.00-0.10 -- -- --
Moderate 0.10-0.20 II 0.50 4000
Severe 0.20-2.00 V 0.45 4500
Very Severe >2.00 V 0.45 4500
2.3 We also subjected samples obtained for expansion index testing to pH and resistivity testing.
These test results can be used to evaluate the potential for corrosivity and sulfate attack on
normal Portland Cement concrete and metal structures, pipes, and reinforcing steel. Test
results indicate the pH of subgrade soil ranges from approximately 7.0 to 7.5. Resistivity
test results indicate soils possess resistivity values ranging from approximately 370 to
570 ohm-cm. Results from the laboratory pH and resistivity testing tests are presented in
Table VI.
2.4 Geocon Incorporated does not practice in the field of corrosion engineering: Therefore, if
improvements that could be susceptible to corrosion are planned, further evaluation by a
corrosion engineer should be considered.
3.0 Seismic Design Criteria
3.1 We used the computer program Seismic Hazard Curves and Uniform Hazard Response
Spectra, provided by the USGS to calculate the seismic ,design criteria. Table 3 summarizes
site-specific design criteria obtained from the 2007 California Building Code (CBC),
Chapter 16 Structural Design, Section 1613 Earthquake Loads. The short spectral response
has a period of 0.2 second. A Site Class C can be used for lots that possess a fill thickness of
less than 20 feet. The 2007 CBC soil profile type is presented on Table VIII.
Project No. 06403-52-32A - -6 - May 12, 2009
TABLE 3
2007 CBC SEISMIC DESIGN PARAMETERS
Parameter Value Reference
Site Class C D Table 16 13.5.2
Fill Thickness, T (Feet) T<20 T>20 --
Spectral Response — Class B(short), S5 1.147g 1. 147g Figure 1613.5(3)
Spectral Response - Class B (1 sec), S 0.434g I 0.434g Figure 1613.5(4)
Site Coefficient, Fa 1.000 1 1.041 Table 1613.5.3(1)
Site Coefficient, F 1.366 1.566 Table 1613.5.3(2)
Maximum Considered Earthquake
Spectral Response Acceleration (short), SMS
1.147g 1. 194g Section 1613.5.3 (Eqn 16-37).
Maximum Considered Earthquake
Spectral Response Acceleration - (1 sec), 5M1
0.592g 0.679g Section 1613.5.3 (Eqn 16-38)
5% Damped Design
Spectral Response Acceleration (short), SDS
0.7659 0.796g Section 1613.5.4 (Eqn 16-39)
5% Damped Design
Spectral Response Acceleration (1 see), S01 0.395g 0.453g Section 16 13.5.4 (Eqn 16-40)
3.2 Conformance to the criteria in Table 3.1 for seismic design does not constitute any kind of
guarantee or assurance that significant structural damage or ground failure will not occur if a
maximum level earthquake occurs. The primary goal of seismic design is to protect life and
not to avoid all damage, since such design may be economically prohibitive.
4.0 Foundation and Concrete Slabs-On-Grade Recommendations
4.1 The foundation recommendations herein are for proposed one- to three-story residential
structures. The foundation recommendations have been separated into three categories based
on either the maximum and differential fill thickness or Expansion Index. The foundation
category criteria are presented in Table 4.1.
TABLE 4.1
FOUNDATION CATEGORY CRITERIA
Foundation
Category
Maximum Fill .
Thickness, T (feet)
Differential Fill
Thickness, D (feet)
Expansion Index
(El)
I T<20 -- EI<50
II 20<T<50 10<D<20
-
50<EI<90
III T>50 D>20 90<EI<130
Project No. 06403-52-32A -7- May 12, 2009
4.2 Table 4.2 presents minimum foundation and interior concrete slab design criteria for
conventional foundation systems.
TABLE 4.2
CONVENTIONAL FOUNDATION RECOMMENDATIONS BY CATEGORY
Foundation Minimum Footing
Embedment Depth Continuous Footing Interior Slab
Category, (inches) Reinforcement Reinforcement
I 12 Two No. 4 bars, 6 x 6 - 10/10 welded wire
one top and one bottom mesh at slab mid-point
II 18 Four No. 4 bars, No. 3 bars at 24 inches
two top and two bottom on center, both directions
III 24 Four No. 5 bars, No. 3 bars at 18 inches
two top and two bottom on center, both directions
4.3 The embedment depths presented in Table 4.2 should be measured from the lowest adjacent
pad grade for both interior and exterior footings. The conventional foundations should have a
minimum width of 12 inches and 24 inches for continuous and isolated footings,
respectively. Figure 3 presents a typical wall/column footing dimension detail.
4.4 The concrete slab-on-grade should be a minimum of 4 inches thick for Foundation
Categories I and II and 5 inches thick for Foundation Category III.
4.5 Concrete slabs on grade should be underlain by 4 inches of clean sand (3 inches for a 5-inch-
thick slab) to reduce the potential for differential curing, slab curl, and cracking. Slabs that
may receive moisture-sensitive floor coverings or may be used to store moisture-sensitive
materials should be underlain by a vapor retarder placed near the middle of the sand bedding.
The vapor retarder used' should be specified by the project architect or developer based on the
type of floor covering that will be installed. The vapor retarder 'design should be consistent
with the guidelines presented in Section 9.3 of the American Concrete Institute's (ACT) Guide
for Concrete Slabs that Receive Moisture-Sensitive Flooring Materials (ACI 302.2R-06).
4.6 As an alternative to the conventional foundation recommendations, consideration should be
given to the use of post-tensioned concrete slab and foundation systems for the support of the
proposed structures. The post-tensioned systems should be designed by a structural engineer
experienced in post-tensioned slab design and design criteria of the Post-Tensioning Institute
(PTI), Third Edition, as required by the 2007 California Building Code (CBC
Section 1805.8). Although this procedure was developed'for expansive soil conditions,'we
understand it can also be 'used to reduce the potential for foundation distress due to
Project No. 06403-52-32A ' - 8 - May 12, 2009
differential fill settlement The post-tensioned design should incorporate the geotechnical
parameters presented on Table 4.3 for the particular Foundation Category designated. The
parameters presented in Table 4.3 are based on the guidelines presented in the PTI, Third
Edition design manual.
TABLE 4.3
POST-TENSIONED FOUNDATION SYSTEM DESIGN PARAMETERS
Post-Tensioning Institute (PTI),
Third Edition Design Parameters
Foundation Category
1 11 111
Thornthwaite Index -20 -20 -20
Equilibrium Suction 3.9 3.9 3.9
Edge Lift Moisture Variation Distance, em (feet) 5.3 5.1 4.9
Edge Lift, YM (inches) 0.61 1.10 1.58
Center Lift Moisture Variation Distance, em (feet) 9.0 9.0 9.0
Center Lift, YM (Inches) 0.30 0.47 0.66
4.7 The foundations for the post-tensioned slabs should be embedded in accordance with the
recommendations of the structural engineer. If a post-tensioned mat foundation system is
planned, the slab should possess a thickened edge with a minimum width of 12 inches and
extend below the clean sand or crushed rock layer.
4.8 If the structural engineer proposes a post-tensioned foundation design method other than
PTI, Third Edition:
The deflection criteria presented in Table 4.3 are still applicable.
Interior stiffener beams should be used for Foundation Categories II and III..
The width of the perimeter foundations should be at least 12 inches.
The perimeter footing embedment depths should be at least 12 inches, 18 inches and
24 inches for foundation categories I; II, and III, respectively. The embedment
depths should be measured from the lowest adjacent pad grade.
4.9 Our experience indicates post-tensioned slabs are susceptible to excessive edge lift,
regardless of the underlying soil conditions. Placing reinforcing steel at the bottom of the
perimeter footings and the interior stiffener beams may mitigate this potential. Current PTI
design procedures primarily address the potential center lift of slabs but, because of the
placement of the reinforcing tendons in the top of the slab, the resulting eccentricity after
tensioning reduces the ability of the system to mitigate edge lift. The structural engineer
Project No. 06403-52-32A - 9 - . May 12, 2009
should design the foundation system to reduce the potential of edge lift occurring for the
proposed structures.
4.10 During the construction of the post-tension foundation system, the concrete should be placed
monolithically. Under no circumstances should cold joints form between the footings/grade
beams and the slab during the construction of the post-tension foundation system.
4.11 Category I, II, or III foundations may be designed for an allowable soil bearing pressure of
2,000 pounds per square foot (psf) (dead plus live load). This bearing pressure may be
increased by one-third for transient loads due to wind or seismic forces. The estimated
maximum total and differential settlement for the planned structures due to foundation loads
is 1 inch and Y2 inch, respectively.
4.12 Isolated footings, if present, should have the minimum embedment depth and width
recommended fOr conventional foundations for a particular foundation category. The use .of
isolated footings, which are located beyond, the perimeter of the building and support
structural elements connected to the building, are not recommended for Category III. Where
this condition cannot be avoided, the isolated footings should be connected to the building
foundation system with grade beams.-
4.13 For Foundation Category III, consideration should be given to using interior stiffening beams
and connecting isolated footings and/or, increasing the slab thickness. In addition,
consideration should be given to connecting patio slabs, which exceed 5 feet in width, to the
building foundation to reduce the potential for future separation to occur.
4.14' Special subgrade presaturation is not deemed necessary prior to placing concrete; however,
the exposed foundation and slab subgrade soil should be moisture conditioned, as necessary,
to maintain a moist condition as would be expected in any such concrete placement.
4.15 Where buildings or other improvements' are' planned near the top of a slope steeper than 3:1
(horizontal:vertical), special foundations and/or design considerations are recommended due
to the tendency for lateral soil movement to occur. ,
For fill slopes less than 20 feet high or cut slopes regardless of height, building
footings should be deepened such that the bottom outside edge of the footing is at
least 7 feet horizontally from the face of the slope.
When located next to a descending 3:1 (horizontal:vertical) fill slope or steeper, the
foundations should be extended to a depth where the minimum horizontal distance is
equal to H/3 (where H equals the vertical distance from the top of the fill slope to the
Project No. 06403-52-32A _10- May 12,2009.
N
base of the fill soil) with a minimum of 7 feet but need not exceed 40 feet. The
horizontal distance is measured from the outer, deepest edge of the footing to the
face of the slope. An acceptable alternative to deepening the footings would be the
use of a post-tensioned slab and foundation system or increased footing and slab
reinforcement. Specific design parameters or recommendations for either of these
alternatives can be provided once the building location and fill slope geometry have
been determined.
If swimming pools are planned, Geocon Incorporated should be contacted for a
review of specific site conditions.
Swimming pools located within 7 feet of the top of cut or fill slopes are not
recommended. Where such a condition cannot be avoided, the portion of the
swimming pool wall within 7 feet of the slope face be designed assuming that the
adjacent soil provides no lateral support. This recommendation applies to fill
slopes up to 30 feet in height, and cut slopes regardless of height. For swimming pools
located near the top of fill slopes greater than 30 feet in height, additional recom-
mendations may be required and Geocon Incorporated should be contacted for a
review of specific site conditions.
Although other improvements, which are relatively rigid or brittle, such as concrete
flatwork or masonry walls, may experience some distress if located near the top of a
slope, it is generally not economical to mitigate this potential. It may be possible,
however, to incorporate design measures which would permit some lateral soil
movement without causing extensive distress. Geocon Incorporated should be
consulted for specific recommendations.
4.16 The recommendations of this reportare intended to reduce the potential for cracking of slabs
due to expansive soil (if present), differential settlement of existing soil or soil with varying
thicknesses. However, even with the incorporation of the recommendations presented herein,
foundations, stucco walls, and slabs-on-grade placed on such conditions may still exhibit
some cracking due to soil movement and/or shrinkage. The occurrence of concrete shrinkage
cracks is independençof the supporting soil characteristics. Their occurrence may be reduced
and/or controlled by limiting the slump of the concrete, proper concrete placement and
curing, and by the placement of crack control joints at periodic intervals, in particular, where
re-entrant slab corners occur.
4.17 Geocon Incorporated should be consulted to provide additional design parameters as
required by the structural engineer.
5.0 Exterior Concrete Flatwork
5.1 Exterior concrete flatwork not subject to vehicular traffic should be constructed in
accordance with the recommendations herein. Slab panels should be a minimum of 4 inches
Project No. 06403-52-32A - 11 - May 12, 2009
thick and when in excess of 8 feet square should be reinforced with 6x6-W2.91W2.9
(6x6-6/6) welded wire mesh to reduce the potential for cracking. In addition, concrete
flatwork should be provided with crack control joints to reduce and/or control shrinkage
cracking. Crack control spacing should be determined by the project structural engineer
based upon the slab thickness and intended usage. Criteria of the American Concrete
Institute (ACT) should be taken into consideration when establishing crack control spacing.
Subgrade soil for exterior slabs not subjected to vehicle loads should be compacted in
accordance with criteria presented in the grading section prior to concrete placement.
Subgrade soil should be properly compacted and the moisture content of subgrade soil
should be verified prior to placing concrete.
5.2 Even with the incorporation of the recommendations of this report, the exterior concrete
flatwork has a potential to experience some uplift due to expansive soil beneath grade. The
welded wire mesh should overlap continuously in flatwork to reduce the potential for vertical
offsets within flatwork. Additionally, flatwork should be structurally connected to the curbs,
where possible, to reduce the potential for offsets between the, curbs and the flatwork.
5.3 Where exterior flatwork abuts the structure at entrant or exit points, the exterior slab should
be dowelled into the structure's foundation stemwall. This recommendation is intended to
reduce the potential for differential elevations that could result from differential settlement or
minor heave of the flatwork. Dowelling details should be designed by the project structural
engineer. 1. '
6.0 Retaining Walls
6.1 . Retaining walls not restrained at the top and ;having a level backfill surface should be
designed for an active soil pressure equivalent to the pressure exerted by a fluid density of
35 pounds per cubic foot (jcf). Where the backfill will be inclined at no steeper than 2:1
(horizontal:vertical), an active soil pressure of 50 pcf is recommended. These soil pressures
assume that the backfill materials within an area bounded by the wall and a 1:1 plane
extending upward from the base of the wall possess an El of 50 or less. For those lots with
finish grade soils having an El greater than 50 and/or where backfill materials do not
conform to the criteria herein, Geocon Incorporated should be consulted for additional
recommendations.
6.2 Unrestrained walls are those that are allowed to rotate more than 0.001H (where H equals the
height of the retaining portion of the wall in feet) at the top of the wall. Where walls are
restrained from movement at the top, an additional uniform pressure of 7H psf should be
added to the active soil pressure. .
Project No. 06403-52-32A -12- May 12, 2009
6.3 The structural engineer should determine the seismic design category for the project. If the
project possesses a seismic dçsign category. of D, E, or F, the proposed retaining walls
should be designed with seismic lateral pressure. The seismic load exerted on the wall should
be a triangular distribution with a pressure of 23H (where H is the height of the wall, in feet,
resulting in pounds per square foot [psi]) exerted at the top of the wall and zero at the base of
the wall.-
6.4 Unrestrained walls will move laterally when backfilled and loading is applied. The amount
of lateral deflection is dependant on the wall height, the type of soil used for backfill, and
loads acting on the, 'wall. The retaining walls and improvements above the retaining walls
should be designed to incorporate an appropriate amount of lateral deflection.
6.5 Retaining walls should be provided with a drainage system adequate to prevent the buildup
of hydrostatic forces and waterproofed as required by the project architect. The soil
immediately adjacent to the backfilled retaining wall should be composed of free draining
material completely wrapped in Mirafi 140 (or equivalent) filter fabric for a lateral distance
of 1 foot for the bottom two-thirds of the height of the retaining wall. The upper one-third
should be backfilled with less permeable compacted fill to reduce water infiltration. The use
of drainage openings through the base of the wall (weep holes) is not recommended where
the seepage could be a nuisance or otherwise adversely affect the property adjacent to the
base of the wall. A Typical Retaining Wall Drainage Detail is presented in Figure 4. The
recommendations herein assume a properly compacted granular (El of 50 or less)
free-draining backfill material with no hydrostatic forces or imposed surcharge load. If
conditions different than those described are expected, or if specific drainage details are
desired, Geocon Incorporated should be contacted for additional recommendations.
6.6 In general, wall foundations having a minimum depth and width of 1 foot may be designed
for an allowable soil bearing pressure of 2,000 psf, provided the soil within 4 feet below the
base of the wall has an Expansion Index, of 50 or less. The proximity of the foundation to the
top of a slope steeper than 3:1 could impact the allowable, soil bearing pressure. Therefore,
Geocon Incorporated should be consulted where such a condition is expected.
6.7 The recommendations presented herein are generally applicable to the design of rigid
concrete or masonry retaining walls having a maximum height of 8 feet. In the event that
walls higher than 8 feet or other types of walls (such as crib-type walls) are planned, Geocon
Incorporated should be consulted for additional recommendations.
Project No. 06403-52-32A - 13- May 12, 2009
7.0 Lateral Loads
7.1 For resistance to lateral loads, an allowable passive earth pressure equivalent to a fluid
density of 300 pcf is recommended for footings or shear keys poured neat against properly
compacted granular fill or undisturbed formational materials. The allowable passive pressure
assumes a horizontal surface extending away from the base of the wall at least 5 feet or three
times the height of the surface generating the passive pressure, whichever is greater. The
upper 12 inches of material not protected by floor slabs or pavement should not be included
in the design for lateral resistance.
7.2 An allowable friction coefficient of 0.4 may be used for resistance to sliding between soil
and concrete. This. friction coefficient may be combined with the allowable passive earth
pressure when determining resistance to lateral loads.
8.0 Site Drainage and Moisture Protection
8.1 Adequate drainage is critical to reduce the potential for differential soil movement, erosion,
and subsurface seepage. Under no circumstances should water be allowed to pond adjacent
to footings. The site should be graded and maintained such that surface drainage is directed
away from structures and the top of slopes into swales or other controlled drainage devices.
Roof and pavement drainage should be directed into conduits that carry runoff away from the
proposed structure.
8.2 Underground utilities should be leak free. Utility and irrigation lines should be checked
periodically for leaks for early detection of water infiltration and detected leaks should be
repaired promptly. Detrimental soil movement could occur if water is allowed to infiltrate
the soil for a prolonged period of time.
8.3 If detention basins, bioswales, retention basins, or water infiltration devices are being
considered, Geocon Incorporated should be retained to provide recommendations pertaining
to the geotechnical aspects of possible impacts and design. Distress may be caused to
planned improvements and properties 'located hydrologically downstream. The distress
depends on the amount of water to be detained, its residence time, soil permeability, and
other fa,tors. We have not performed a hydrogeology study at the site. Downstream
properties may be subjected to seeps, springs, slope 'instability, raised groundwater,
movement of foundations and slabs,' or other impacts as a result of water infiltration.
Project No. 06403-52-32A • • 14- • May 12, 2009
8.4 - Landscaping planters adjacent to paved areas are not recommended due to the potential for
surface or irrigation water to infiltrate the pavement's subgrade and base course. We
recommend that subdrains to collect excess irrigation water and transmit it to drainage
structures, or impervious above-grade planter boxes be used. In addition, where landscaping
is planned adjacent to the pavement, we recommend construction of a cutoff wall along the
edge of the pavement that extends at least 6 inches below the bottom of the base material.
LIMITATIONS
The conclusions and recommendations contained herein apply only to our work with respect to
grading, and represent conditions on the date of our final observation on May 7, 2009. Any subsequent
grading should be done in conjunction with our observation and testing services. As used herein, the
term "observation" implies only that we observed the progress of the work with-which we agreed to be
involved. Our services did not include the evaluation or identification of the potential presence of
hazardous or corrosive materials. Our conclusions and opinions as to whether the work essentially
complies with the job specifications are based on our observations, experience and test results.
Subsurface conditions, and the accuracy of tests used to measure such conditions, can vary greatly at
any time. We make no warranty, express or implied, except that our services were performed in
accordance with engineering principles generally accepted at this time and location.
We will accept no responsibility for any subsequent changes made to the site by others, by the
uncontrolled action of water, or by the failure of others to properly repair damages caused by the
uncontrolled action of water. The findings and recommendations of this report may be invalidated
wholly or partially by changes outside our control. Therefore, this report is subject to review and
should not be relied upon after a period of three years.
The firm that performed the geotechnical investigation for the project should be retained to provide
testing and observation services during construction to provide continuity of geotechnical interpretation
and to check that the recommendations presented for geotechnical aspects of site development are
incorporated during site grading, construction of improvements, and excavation of foundations. If
another geotechnical firm is selected to perform the testing and observation services during
construction operations, that firm should prepare a letter 'indicating their intent to assume the
responsibilities of project geotechnical engineer of record. A copy of the letter should be provided to
the regulatory agency for their records. In addition, that firm should provide revised recommendations
concerning the geotechnical aspects of the proposed development, or a written acknowledgement of
their concurrence with the recommendations presented in our report. They should also perform
additional analyses deemed necessary to assume the role of Geotechnical Engineer of Record.
Project No. 06403-52-32A - 15 - ' May 12, 2009
If you have any questions regarding this report, or if we may be of further service, p1ase contact the
:
undersigned at your convenience.
S. Very truly yours,
GEOCON INCORPORATED
• /f L/V
Michael C Ertwme li Sadr Shawn Weedon
Senior Staff Geologist CEG 1778 GE 2714
ir (4/del) Addressee P8 M No. 171
CERTIFIED (e-mail) ColRich Job Trailer ENGINEERING Zu
Attention: 'Mr. Kirk
Exp.
Philo
oFEss:
I
, I. ,:.., .'.:.•' J fi4 S SOURCE 2007 THOMAS BROTHERS MAP 11 S SAN DIEGO COUNT( CALIFORNIA N 5 Mnp( Rand. McNally, R.L08-S-100, eprcüce with permission: tie uniewful tocy NO SCALE or raproduce who for personal use or, resale without permission
S -'
GEOCON VICINITYMAP
INC OR P0 RA-T ED ; VILLAGES OF LA-COSTA,'- THE GREENS
GEOTEa-NICALCONSULTANTS NEIGHBORHOOD 1.03', LOTS-'I.,-THROUGH 38 6960 FLANDERS DRIVE - SAN DIEGO, CALIFORNIA 9211-.2974/, CARLSBAD, CALIFORNIA PHONE 858 558-6900 - FAX 858 558-6159 , I..:• . .
ME/AMI F :.. DATE 05-12-2009 IPROJECT NO. 06403-52-32A FIG.1
Vá*iMp -: - : - - i -,
-• 2 ,. - . -; . - -
I - SI •••- '7; :-: .•: ..
:- .:
--
:- ;: -: -
: . -.
WALL FOOTING
CONCRETE SLAB •
44 4
f
4
SAND _-:;'\ : •. :... PAD GRADE
0 ••':':i ;.:.
MOISTURE
INHIBITOR 4 I
4
LL
I • FOOTING
-. - WIDTH
COLUMN FOOTING
CONCRETE SLAB. . .
.:.-. ••
• : ..1 .•
-SAND
MOISTURE
SAND
":
INHIBITOR
LL
_
FOOTING WIDTH
1
NO SCALE
*SEE REPORT FOR FOUNDATION WITDH AND DEPTH RECOMMENDATION
WALL/ COLUMN FOOTING DIMENSION DETAIL
GEOTECHNICAL CONSULTANTS
6960 FLANDERS DRIVE- SAN DIEGO, CALIFORNIA 92121-2974
PHONE 858 558-6900 - FAX 858 558-6159
ME/AML
.
DSK/E0000
VILLAGES OF IA COSTA - THE GREENS
NEIGHBORHOOD 1.03, LOTS 1 THROUGH 38
CARLSBAD, CALIFORNIA
DATE 05- 12- 2009' PROJECT NO. 06403 - 52- 32A FIG. 3
:
W
•
GEOCON
INCORPORATED VILLAGES Of- .A COSTA - THE GREENS
NEIGHBORHOOD 1.03, LOTS 1 THROUGH 38
g, A en A RL)DID, CALIFORNIA GEOTEOINICAL CONSULTANTS
6960 FLANDERS DRIVE - SAN DIEGO, CALIFORNIA 92121- 2974
PHONE 858 558-6900.- FAX 858 558-6159
ME/AML DSK/GTYPD DATE 05- 12- 2009 PROJECT NO. 06403 -52 32A FIG. 4
RvMW
S . -
TABLE I
SUMMARY OF FIELD DENSITY TEST RESULTS
Elev. Plus Field Field Field Req'd.
or 3/4" Dry Moist. Rel. Re!.
Depth Curve Rock Dens. Cont. Comp. Comp.
Test No. Date Location No. (%) (pc
1 12/02/08 Cinnabar Way 11+00 '
SZ 2 12/02/08 Lot 38; Southwest
3 12/02/08 Cinnabar Way 11+05
4 12/03/08 Lot 38
SZ 5 12/03/08 Lot 38
SZ 5 A 12/03/08 Lot 38
6 12/03/08 Lot 38
6A 12/03/08 Lot 38
7 12/03/08 Lot 38
SZ 8 12/03/08 Lot 1; West
SZ 9 12/03/08 Lot 1; West
SZ 10 12/03/08 Lot 1; West
SZ 11 12/03/08 Lot 1; West
12 12/03/08 Lot 1
SZ 13 12/03/08 Lot 1; West
14 12/03/08 Lot 2
15 12/05/08 Lot 1
16 12/05/08 Lot
17 12/05/08 Lot 4
18 12/05/08 Lot
19 12/08/08 Lot 1
20 . 12/08/08 Lot 3
21 12/08/08 Lot 4
22 12/08/08 Lot 6
23 12/08/08 Lot 7
24 12/09/08 Lot 9
25 12/09/08 Lot 10
26 12/09/08 Lot 12
27 12/09/08 Lot 13
28 12/09/08 Lot 15
29 12/10/08 Lot 16
30 12/10/08 Lot 17
SZ 31 12/11/08 Lot 32; North
SZ 32 12/11/08 Lot 34; North
SZ 33 01/16/09 Lot 1; South
ST 34 01/16/09 Lot 1; South
SZ 35 01/16/09 Lot 1; South
SZ 36 01/16/09 Lot 1; South
SZ 37 01/20/09 Lot 1; South
,SZ 38 01/20/09 Lot 1; South
SZ 39 01/21/09 Lot 1; South
ST 40 01/21/09 Lot 38;West
FG 41 03/16/09 Lot 8
FG 42 03/16/09 Lot 7
FG 43 03/16/09 Lot 6
291 4 0 104.6 15.7 90 90
294 3 0 109.7 14.5 91 90
296 3 0 108.4 13.3 90 90
299 3 0 109.6 15.5 91 90
302 3 0 107.4 16.8 89 90
302 3 0
--------------------------------------------------------------------------------------------
109.6 15.0 91 90
304 3 0 104.5 18.9 87 90
304 3 0 111.7 14.7 93 90
306 3 0 109.5 16.9 91 90
295 3 0 110.8 12.6 9290
294 3 0 110.2 12.9 92 90
297 3 0 112.4 13.6 94 90
293 3 0 108.8 14.7 91 90
296 3 . 0 109.2 12.6 91 90
299 3 0 109.4 13.2 91 90
305 3 0 110.1 14.3 92 90
302 5 0 104.8 19.4 92 90
306 5 0 103.9 19.0 92 90
308 3 0 111.6 12.4 93 90
309 3 0 109.4 13.8 91 90
305 3 0 110.6 12.8 92 90
308 3 0 108.2 13.6 90 90
309 3 0 108.9 13.1 91 90
310 4 0 107.3 16.8 92 90
310 4 0 105.4 14.5 .90 90
312 3 0 109.2 12.9 91 90
318 3 0 108.4 13.4 90 90
317 1 0 111.6 12.1 90 90
318 1 0 112.9 12.8 91 90
319 1 0 112.4 11.7 90 90
.318 1 0 111.8 12.4 90 90
319 1 0 111.9 12.9 90 90
315 3 0 108.8 13.2 91 90
316 3 0 110.2 12.5 92 90
293 30 108.6 13.7 90 90
296 3 0 108.9 11.9 91 90
300 3 0 109.9 12.8 .92 90
304 3 0 109.5 12.6 91 90
305 1 0 112.3 11.5 90 90
306 .0 110.8 13.3 92 90
2971 0 111.9 11.3 90 90
311 3 0 111.3 15.6 93 90
312 4 0 104.7 14.1 90 90
312 3 0 111.6 12.4 93 90
311 3 0 109.9 13.7 92 90
Project No. 06403-52-32A May 12, 2009
TABLE I
SUMMARY OF FIELD DENSITY TEST RESULTS
Elev. Plus Field Field Field Req'd.
or 3/4" Dry Moist. Rel. Rel.
Depth Curve Rock Dens. Cont. Comp. Comp.
Test No. Date Location (fl) No. (%) (PcO.
FG 44 03/17/09 Lot 5 311 4 0 102.0 15.7 88 90
FG 44 A 03/25/09 Lot 5 311 4 0 105.6 15.6 91 90
FG 45 03/17/09 Lot 309 4 0 106.3 13.9 91 90
FO 46 03/17/09 Lot 3 308 3 0 110.3 13.9 92 90
FG 47 03/17/09 Lot 2 307 4 0 105.2 14.5 90 90
FG 48 03/17/09 Lot 1 306 3 0 108.1 13.1 90 90
SZ 49 03/17/09 Lot 14; South 301 1 0 114.1 12.1 92 90
SZ 50 03/17/09 Lot 13; South 310 3 0 112.7 11.8 94 90
SZ 51 03/18/09 Lot 16; South 314 3 0 108.9 14.3 91 90
SZ 52 03/18/09 Lot 14; South -
312 1 0 111.5 13.3 90 90
SZ . 53 03/18/09 Lot 15; South 1 315 3 0 108.5 13.6 90 90
SZ 54 03/18/09 Lot 14; South 317 3 0 108.5 13.6 90 90
SZ 55 03/18/09 Lot 16; South 318 3 0 111.4 12.4 93 90
SZ 56 03/19/09 Lot 17; South 319 3 0 108.6 14.6 90 90
SZ 57 03/19/09 Lot 35; North 320 3 0 109.3 13.7 91 90
SZ 58 03/19/09 Lot 33; North • 319 3 0 109.0 13.9 91 90
SZ 59 03/20/09 Lot 34; North - 321 3 0 108.9 • 13.6 91 90
SZ 60 03/20/09 Lot 32; North • 322 3 0 111.4 14.0 93 90
FG 61 03/20/09 Lot 38 309 3 0 108.6 12.4 90 90
FG 62 03/20/09 Lot 37 311 3 0 109.2 13.3 91 90
FG 63 03/20/09 Lot 36 312 3 0 109.0 11.8 91 90
FG 64 03/24/09 Lot 17 321 1 0 113.3 13.6 91 90
FG 65 03/24/09 Lot 16 320 1 0 111.6 12.1 90 90
FG 66 03/24/09 Lot 15 320 1 0 111.9 12.7 90 90
FG 67 03/25/09 Lot 14 • 320 1 0 114.2 11.5 92 90
FG 68 03/25/09 Lot 13 319 • • - 1. - 0 112.8 13.6 91 90
FG 69 03/25/09 Lot 12 319 1 0 111.8 13.0 90 90
FG 70 03/25/09 Lot 11 - 318 1 0 113.2 12.5 91 90
FG 71 03/25/09 Lot 10 314 3 0 108.7 12.6 91 90
FG 72 03/25109 Lot 314 3 0 109.8 13.7 91 90
FG 73 03/25/09 Lot 32 324 4 0 110.1 16.0 95 90
FG 74 03/25/09 Lot 33 324 4 0 107.3 13.8 92 90
FG 75 03/25/09 Lot 34 323 4 0 104.9 14.7 90 90
FG 76 03/25/09 Lot 35 323 4 0 104.7 14.2 90 90
FG • 77 03/30/09 Lot 31 323 13 0 110.6 12.8 92 90
FG 78 03/30/09 Lot 30 • 323 4 0 106.0 13.8 91 90
FO 79 03/30/09 Lot 29 322 4 0 104.7 14.9 90 90
FG 80 03/30/09 Lot 28 327 3 0 111.0 13.7 92 90
FG 81 03/31/09 Lot 27 322 3 0 108.1 14.1 90 90
FG
-
82 03/31/09 Lot 26 322 . • 3 0 108.7 11.8 91 90
FG 83 03/31/09 Lot 25 ..320 3 0 108.2 12.6 90 90
FG 84 04/01/09 Lot 18 • 310 4 0 104.9 13.7 90 90
FG 85 04/01/09 Lot 19 321 4 0 107.1 15.2 92 90
FG 86 04/01/09 Lot 20 321 3 0 108.3 12.9 90 90
FG 87 04/01/09 Lot 21 320 3 0 109.5 13.4 91 90
Project No. 06403-52-32A May 12, 2009
•
I TABLE I -'
• SUMMARY OF FIELD DENSITY TEST RESULTS
S Elev. Plus Field Field Field Reqd.
5 or 3/4' Dry Moist. Rel.
/ Depth Curve Rock Dens. Cont. Comp. Comp.
S Test No. Date Location (ft) No. (°) (P (%) (%) (%)
S ST 88 04/01/09 Lot 31; East 311 3 0 110.7 12.1 92 90
5 FG 89 04/21/09 Lot 22 - 321 3 0 112.8 11.7 94 90
FG . 90 04/21/09 Lot 23 321 3 0 110.4 12.6 92 90 •
FG 91 04/21/09 Lot24 321 3 0 111.0 12.1 92 90
5 ST 92 05/05/09 Lot 1; South - 287 3 0 112.3 12.5 94 90
5 ST 93 05/05/09 Lot 1; South 291 3 0 109.1 13.6 91 90
ST 94 05/07/09 Lot 33; North 321 3 0 108.5 12.3 90.-, 90
•
-
S S. .5
5 S
• H •
S. S •
•
55 .
S.
I.
S
. •
55
• S5 5..
5
.
• ., S
S .
S
S
S S
0
• S
•
S
..
S 0
• S. S . -.
S . S
5 Project No. 06403-52-32A May 12, 2009.
•
0 :.
TABLE I
EXPLANATION OF CODED TERMS
/
TEST SUFFIX 0
A, B, C,... : Retest of previous density test failure, following moisture conditioning and/or recompaction.
- STRIKE-OUT
Fill in area of density test failure was removed and replaced with properly compacted fill soil.
- PREFIX CODE DESIGNATION FOR TEST NUMBERS
FG - FINISH GRADE ST - SLOPE TEST
SZ - SLOPE ZONE
-CURVE NO.
Corresponds to curve numbers listed in the summary of laboratory maximum dry density and optimum
moisture content test results table for selected fill soil samples encountered during testing and observation.
- ROCK CORRECTION
For density tests with rock percentage greater than zero, laboratory maximum dry density and optimum
moisture content were adjusted for rock content. For tests with rock content equal to zero, laboratory
maximum dry density and optimum moisture content values are unadjusted.
-TYPE OF TEST
SC: Sand Cone Test (ASTM D1556)
NU: Nuclear Density Test (ASTM D2922)
OT: Other
- ELEVATION/DEPTH
Test elevations/depths have been rounded to the nearest whole foot.
- LOCATION DESCRIPTION
(IP): Indicates in-place tests. Where (IP) appears in the location description, the compaction procedures
were not observed by a representative of Geocon. Tests were taken at the surface or in test pits after
placement of the fill. The results of these tests are indicative of the relative compaction at the location of
the test only and may not be extrapolated to adjacent areas. Geocon has no opinion regarding the relative
compaction of fill in adjacent areas. •
Project No. 06403-52-32A 0 May 12, 2009
TABLE II
SUMMARY OF LABORATORY MAXIMUM DRY DENSITY AND
OPTIMUM MOISTURE CONTENT TEST RESULTS
ASTM DI557
Sample No. Description Maximum Dry
Density (pci)
Optimum Moisture
Content (%)
1 Olive brown, Silty SAND 124.2 11.0
2 Brown, Clayey SAND 127.4 10.2
3 Dark brown, Clayey, fine to medium SAND 120.1 11.9
4 Light yellowish brown, Silty SAND 116.5 13.3
5 Light brown to reddish brown, Silty to Clayey SAND 113.4 15.0
6 Yellowish brown, Clayey, fine to mediumSAND 122.5 11.3
TABLE III
SUMMARY OF LABORATORY DIRECT SHEAR TEST RESULTS
ASTM D 3080
Sample No. Dr' Density
(pci).
Moisture Content (%)
. Unit Cohesion
(psi)
Angle of
Shear Resistance
(degrees) Initial I Final
1 110.1 12.5 23.4 270 32
2 114.2 10.4 - 18.4 225 33
Samples were remolded'to approximately 90 percent of laboratory maximum dry density at near optimum moisture
content.
TABLE IV
SUMMARY OF LABORATORY EXPANSION INDEX TEST RESULTS
ASTM D 4829
Lot No.
1•
Sample
No.
Moisture Content (°1'°) Dry Density
(pet)
Expansion
Index
Expansion
Classification Before Test After Test
I through 4 El-A 10.9 21.5 . • 111.2 28 Low
5 through 8 El-B 10.5 21.0 111.0 32 Low
9 through 12 El-C 10.0 20.5 108.7 . 47 Low
13 through 17 EI-D 9.3 20.9 -
109.9 46 Low
18 through 21 EI-E 9.8 22.0 109.2 62 Medium
22 through 26 El-F 10.3 24.2 107.1 68 Medium
27through31 El-G 10.3 21.7 107.2 54 Medium
32through35 El-H 9.7 20.9 108.7 50 Low
36through38 El-1 1 10.0 21.4 1 108.6 58 Medium
Project No. 06403-52-32A May 12, 2009
Sample No. pH Resistivity (ohm/cm)
El-A 7.2 • 500
El-B 5 7.3 510
El-C 7.0 440
EID 7.2 440
EI-E • 7.4 • 500
El-F * . 7.5 0 • 480
El-G 7.1 * 460
El-H 73 570
El-I 7.1 • 370
a
•
1 TABLE Vt
SUMMARY OF LABORATORY POTENTIAL OF HYDROGEN (pH),
RESISTIVITY, CALIFORNIA TEST NO. 643
S S
•
.'
I TABLE
SUMMARY OF WATER SOLUBLE SULFATE LABORATORY TEST RESULTS
.
CALIFORNIA TEST NO. 417
Sample No. Water Soluble Sulfate (%) Sulfate Exposure
El-A * 0.320 Severe
El-B 0.303 Severe
El-C .0.344 Severe
EI-D 0.310 Severe
EI-E 0.230 Severe
El-F 0.341 Severe
El-G . 0.183• Moderate
El-H 0.310 Severe
El-I - 0.189 Moderate
•
I.
•0
*
••
S . ••-. •0
•0
•
0 0•
. S •• *
• Project No. 06403-52-32A
S •S 0
May 12,2009
TABLE VII
SUMMARY OF AS-GRADED RESIDENTIAL BUILDING PAD CONDITIONS
THE GREENS, NEIGHBORHOOD 1.03
LOTS I THROUGH 38
Approximate Approximate
Maximum Maximum Depth Expansion Recommended
Lot No. Pad Condition Depth of Fill of Fill Differential Index Foundation
(feet) (feet) Category
Fill 20 13 28 II
2 Undercut due to 15 12. 28 II cut/fill transition
3 Undercut due to 8 5 28 1 cut/fill transition
4 Undercut due to 4 cut/fill transition
1 28 I
5 Undercut due to 13 cut/fill transition
9 32 I
6
Undercut due to 8
cut/fill transition
4 32 I
Undercut due to 7 . 9 cut/fill transition
5 32 I
8
Undercut due to 12 8 32 1
cut/fill transition
9 Fill 13 10 47 II
10 Fill 15 7 . 47 1
11 Fill 9 1 47 I
12 Fill 11 3 47 I
13 Fill 19 12 46 II
14 Fill 19 12 46 II
15 Undercut due to 8 . cut/fill transition
5 46
16 Undercut due to 5 cut/fill, transition
2 46 I
17 Undercut due to 4 1 46 I' cut/fill transition
18 Fill 20 10 62 II
19 Fill 23 13 62 II
20 Fill 11 . 4 62 II
21 . Fill . 9. 2 62 II
22 Fill 19 11 68 . II
23 Fill 13 6 68 II
24 Fill 10 . 3 68 II
25 ' Fill 14 9 . 68 II
26 Fill 16 10 68 II
27 Fill 16 10 54 II
28 Fill 20 11 54 II
Project No. 06403-52-32A May 12, 2009
TABLE VII (Continued)
SUMMARY OF AS-GRADED RESIDENTIAL BUILDING PAD CONDITIONS
THE GREENS, NEIGHBORHOOD 1.03
LOTS I THROUGH 38
Lot No. Pad Condition
Approximate
Maximum
Depth of Fill
(feet)
Approximate
Maximum Depth
of Fill Differential
(feet)
Expansion
Index
Recommended
Foundation
Category
29 Fill 18 10 54 II
30 Fill •. ' 16 .. 6 54 II
31 Fill 11 ' 1 54 ' II
32 -' Fill 16 6 50 I
33 Fill 12 2 50 I
34 ' Fill 11 1 50 I
35 Fill 10 1 50 I
36 Fill 7 2 58 II
37, Fill' 12 8 58 1 II
38 Fill 11 ' 6 58 II
,1
TABLE VIII
THE GREENS. NEIGHBORHOOD 1.03,
LOTS I THROUGH 38
Lot No. '
'
2007 CBC Soil Profile Type
I D '
2 through 17. , ,
,18 and 19 .''' . D
20 through 27 ' C
28 - ' ' D
29 through 38 C -
Project No. 06403-52-32A'
' '
May 12, 2009