HomeMy WebLinkAboutCT 94-02; Date and Olive Subdivision - Lucas & Mercier Development; GEOTECHNICAL INVESTIGATION FOR DATE AND OLIVE SUBDIVISION; 1994-01-14c
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GEOTECHNICAL INVESTIGATION
FOR
DATE AND OLIVE SUBDIVISION
CARLSBAD, CALIFORNIA
PREPARED FOR
LUCAS & MERCIER DEVELOPMENT INC
RANCHO SANTA MARGARITA, CALIFORNIA
PREPARED BY
GEOCON INCORPORATED
SAN DIEGO. CALIFORNIA
JANUARY 1994
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GEOCON
INCORPORATED
Geotechnical Engineers and
Engineering Geologists
Project No. 05252-12-01
January 14, 1994
Lucas & Mercier Development Inc.
29712 Avenida de Las Banderas
Rancho Santa Margarita, California 92688
Attention:
Subject:
Gentlemen:
Mr. Dennis Hendrickson
DATE AND OLIVE SUBDIVISION
CARLSBAD, CALIFORNIA
GEOTECHNICAL INVESTIGATION
In accordance with your authorization and our proposal dated September 23, 1993, we have
performed a geotechnical investigation for the subject project. The accompanying report presents the
findings from our study and our conclusions and recommendations pertaining to the geotechnical
engineering aspects of the project development.
If you have any questions regarding this report, or if we may be of further service, please contact the
undersigned at your convenience.
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Very truly yours,
INCQRPORA
AS
(3)
(3)
Addressee
BHA Incorporated
Attention: Mr. Ron Hollo"
6960 Flanders Drive
San Diego, CA 92121-2974
619 558-6900
FAX 619 558-6159
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TABLE OF CONTENTS
PURPOSE AND SCOPE 1
SITE AND PROJECT DESCRIPTION 1
SOIL AND GEOLOGIC CONDITIONS 2
Topsoils (Unmapped) 2
Terrace Deposits (Qt) 3
f GROUNDWATER 3
GEOLOGIC HAZARDS 3
r Faulting and Seismicity 3
™ Liquefaction 5
F CONCLUSIONS AND RECOMMENDATIONS 6
•• General 6
Soil and Excavation Characteristics 6
F Grading 6
m Foundations 8
Concrete Slab-On-Grade 9
P Retaining Wails and Lateral Loads 10
L Site Drainage and Moisture Protection 12
Grading and Foundation Plan Review 12
L LIMITATIONS AND UNIFORMITY OF CONDITIONS
^ MAPS AND ILLUSTRATIONS
Figure 1, Geologic Map
JM Figure 2, Wall/Column Footing Dimension Detail
L Figure 3, Retaining Wall Drainage Detail
p. APPENDIX A
L FIELD INVESTIGATION
Figures A-l - A-5, Logs of Borings
f APPENDIX B
" LABORATORY TESTING
Table B-I, Summary of Direct Shear Test ResultsCTable B-II, Summary of Laboratory Maximum Dry Density and Optimum Moisture
Content Test Results
Table B-III, Summary of Laboratory Expansion Index Test Results
P Figure B-l, Consolidation Curve
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APPENDIX C
T RECOMMENDED GRADING SPECIFICATIONS
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Project No. 05252-12-01
January 14, 1994
p GEOTECHNICAL INVESTIGATION
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£ PURPOSE AND SCOPE
p . This report presents the results of a geotechnical investigation for the proposed subdivision
development north of Agua Hedionda Lagoon, in the city of Carlsbad, California (see Vicinity Map
i inset on Figure 1). The purpose of the investigation was to evaluate the surface and subsurface soil
and geologic conditions at the site and, based on the conditions encountered, to provide recommenda-
fc" lions relative to the geotechnical engineering aspects of project development.
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The scope of the field investigation consisted of a site reconnaissance by an engineering geologist and
Li the excavation of 5 exploratory borings. A detailed discussion of the field investigation is presented
^" in Appendix A. In addition, a review of aerial photographs and relevant soil and geologic literature
concerning the site was performed. The recommendations presented herein are based on an analysis
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^ of the data obtained and experience with similar soil and geologic conditions.
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SITE AND PROJECT DESCRIPTION
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L The subject property consists of approximately 31,500 square feet of vacant land located just east of
_ Garfield Avenue, bounded by Date Avenue on the north and Olive Avenue on the south in Carlsbad,
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California (see Geologic Map, Figure 1). Topographically, the site slopes gently toward the northeast
i with elevations ranging from 43 feet Mean Sea Level (MSL) along the western boundary to 37 feet
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MSL near the northeast corner of the property. The project site is currently covered by native
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January 14, 1994
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^ grasses and a few large trees. An existing sewer line traverses the site along the eastern propertyk,
margin.
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^ - It is our understanding that proposed site development will consist of grading the site to receive six
single family residential units and constructing roadway improvements along the two frontage streets.
f> The grading will be minimal with cut and fill of less than 5 feet. Earthwork operations will involve
importing 1,500 cubic yards of soil.
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The locations and descriptions contained herein are based on a site reconnaissance and the plan
entitled Tentative Subdivision Map Development Plan, prepared by BHA Incorporated, and dated
^ December 20, 1993.
SOIL AND GEOLOGIC CONDITIONS
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^, The site is underlain by one surficiai soil type and one geologic unit: topsoils and Terrace Deposits.
*• Each of these is described herein:
^ Topsoils (Unmapped)
^ A thin layer topsoil was encountered in all borings that extended approximately 1 to 2 feet below the
existing ground surface. These material consisted of loose, damp to moist, brown, fine to medium,
f"k slightly clayey to silty sand. Due to the unconsolidated nature of these materials, complete removal
and recompaction will be required in areas to receive fill or settlement sensitive structures.
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Project No. 05252-12-01
January 14, 1994
*» Terrace Deposits (Ot)
L Dense formational Quaternary-aged Terrace Deposits were encountered in all borings underlying the
L surficial deposits to the maximum depth of exploration. This unit is characterized as dense, damp
^ . to moist, orange to red-brown, slightly cemented, slightly silty fine to medium sand. The Terrace
k Deposits should provide suitable foundation support in either a dense natural or properly compacted
r state.
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fc" GROUNDWATER
^ No groundwater or seepage was encountered within the exploratory borings; therefore, groundwater-
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related problems are not anticipated to significantly impact project development, provided the
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U recommendations contained herein are implemented.
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GEOLOGIC HAZARDS
r^ Faulting and Seismicitv
^ It is our opinion, based on our field investigation, and review of aerial photographs and published
te geologic maps, the site is not located on any active or potentially active fault trace as defined by the
California Division of Mines and Geology.
The Rose Canyon and Coronado Banks Fault Zones, the closest active faults, lie approximately 4
i and 17 miles, respectively, to the west. As shown on Table I, a "maximum probable" earthquake
of Magnitude 6.5 occurring on the Rose Canyon Fault could result in a peak site acceleration of
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Project No. 05252-12-01
January 14, 1994
approximately 0.32g. Other active faults listed on Table I are more distant from the site and, hence,
ground shaking from earthquakes on those faults will be less intensive. It is our opinion that the site
could be subjected to moderate to severe ground shaking in the event of a major earthquake along any
of the above-mentioned faults; however, the seismic risk at the site is not considered significantly
greater than the surrounding area.
TABLE I*
DETERMINISTIC SITE PARAMETERS FOR SELECTED FAULT
Fault Name
Casa Loma-Clark (San Jacinto)
Coronado Banks Fault Zone
Coyote Creek (San Jacinto)
Elsinore
Gin. Heien-Lytle Cr-Clremnt
Newport - Inglewood
Rose Canyon
San Diego Trough
Distance
From
Site
(miles)
51
17
54
28
54
42
4
27
Maximum Credible Event
Maximum
Credible
(Mag)
7.50
6.75
7.50
7.50
7.50
7.50
7.00
6.50
Peak
Site
Acceleration
(g)
0.04
0.12
0.04
0.10
0.04
0.06
0.42
0.06
Maximum Probable Event
Maximum
Probable
(Mag)
7.00
6.00
7.00
6.75
7.00
6.50
6.50
6.00
Peak
Site
Acceleration
(g)
0.03
0.08
0.03
0.07
0.03
0.03
0.32
0.05
* Derived from Blake T. F. EQFAULT, Computer Program for Deterministic Prediction of
Peak Horizontal Acceleration from Digitized California Faults, 1989, a, updated 1993.
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Project No. 05252-12-01
January 14, 1994
Liquefaction
In view of the dense formational soils underlying the site and lack of a permanent water table near
the ground surface, it is our opinion that liquefaction does not present a significant geologic hazard
to the proposed site development.
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January 14, 1994
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IP CONCLUSIONS AND RECOMMENDATIONS
General
^ 1. It is our opinion that no soil and geologic conditions were encountered during the course of
p _ the investigation which would preclude the development of the proposed building, providedLthe recommendations of this report are followed.
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2. No potential geologic hazards were observed or are known to exist on the site which would
** adversely affect the proposed project.
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Soil and Excavation Characteristicsr*
w 3. Based on our field observations and laboratory tests, the prevailing soils are comprised of
*"" "low" to "very low" expansive, fine to medium silty to slightly clayey sand of topsoils and
the Terrace Deposits. The expansive character of the soil is defined in accordance with the
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^ Uniform Building Code (UBC) Table 29-C.
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4. Excavation of these soils should be possible with light to moderate effort with conventional
^ heavy-duty equipment.
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Grading
k 5. All grading should be performed in accordance with the city of Carlsbad grading ordinance
and the Recommended Grading Specifications contained in Appendix C of this report. Where
Project No. 05252-12-01
January 14, 1994
f« the recommendations of Appendix C conflict with this section of the report, the recommend-
ations of this section shall take precedence.
p. - 6. Prior to commencing grading, a preconstruction conference should be held at the site with
the grading contractor, civil engineer, and geotechnical engineer in attendance. Special soil
- handling and/or the Grading Plan can be discussed at that tune.fa
^" 7. Site preparation should begin with the removal and export of all deleterious material and
^ vegetation. In the area of the existing trees and tree stumps, deep root structures should be
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anticipated that may generate highly organic materials, unsuitable for placement in the fills.
*• All unsuitable soils, should be removed and the exposed natural ground surface properly
^* moisture conditioned as necessary and recompacted to a minimum relative compaction
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of 90 percent, based on ASTM Test Procedure D1557-91. Aside from the root structure
^ removal, the average depth of remediation is anticipated to be approximately 2 to 3 feet. Fill
p soils free of deleterious materials should then be placed and compacted to at least 90 percent
of maximum dry density until finish grade is attained.
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p, 8. In areas of remedial grading, especially where trees and stumps are removed, a cut-fill
condition will be created. To reduce the potential for differential settlement, it is
recommended that the cut portion of the cut-fill transition within building areas be undercut
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Project No. 05252-12-01
January 14, 1994
P at least 3 feet and replaced with properly compacted fill soils. The undercut area should
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extend a minimum of 5 feet beyond the structure footprint.
9. Necessary precaution should be taken during the remedial grading operation adjacent to the
masonry wall located at the west-central portion of the property.
10. It is recommended that all imported fill soils be "low" expansive with an Expansion Index
of less than 50 and free of organic matters. Geocon Incorporated should test the planned
import soils at the source and approve the material prior to importing.
11. All fill and trench and utility backfill greater than 12 inches in depth should also be
compacted to a minimum relative compaction of 90 percent.
Foundations
12. The site is suitable for the use of isolated spread footings and/or continuous wall footings.
It is recommended that continuous foundations have a minimum width of 12 inches and a
minimum depth below lowest adjacent pad grade of 12 inches. Such foundations may be
designed for an allowable soil bearing pressure of 2,000 psf. Isolated spread footings should
have a minimum dimension of 2 feet and bear at least 18 inches into compacted fill soils.
Spread footings with these minimum dimensions may be designed for the allowable bearing
capacity of 2,500 psf. The allowable bearing capacity is for dead plus live loads and may
Project No. 05252-12-01
January 14, 1994
be increased by one-third for transient loads. Figure 2 presents a wall/column footing
dimension detail.
_ . 13. It is recommended that continuous footing reinforcement consist of at least two No. 4 steel
L reinforcing bars placed horizontally in the footings, one near the top of the footing and one
p«; near the bottom. The above reinforcement is based on soil support characteristics and is not
intended to be in lieu of reinforcement necessary for structural considerations.
^ 14. These foundation recommendations are preliminary and will be finalized after earthwork
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operations are completed and as-graded conditions are known. Foundation recommendations
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to for Lot Nos. 3 and 6 may be modified to account for the location of the eastern perimeter
^* footings in relation to the existing sewer line.
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^g Concrete Slab-On-Grade
•* 15. It is recommended that the concrete slab-on-grade have a thickness of at least 4 inches and
ite be reinforced with at least 6 x 6-10/10 welded wire mesh. The slab-on-grade should be
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underlain by 4 inches of clean sand with a Sand Equivalent of at least 30. Where moisture
p, sensitive floor coverings are planned or where moisture migration through the slab would
to become a nuisance, a visqueen moisture barrier protected by 2 inches of the sand bedding
p»should be provided.
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Project No. 05252-12-01
January 14, 1994
16. The recommendations presented herein are intended to reduce the potential for cracking of
slabs and foundations. However, even with the incorporation of the recommendations
presented herein, foundations and slabs-on-grade placed on such conditions may still exhibit
some cracking. The occurrence of concrete shrinkage cracks are independent of 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 and in particular where re-entry slab
corners occur.
Retaining Walls and Lateral Loads
17. 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
30 pounds per cubic foot (pcf). Where the backfill will be inclined at no steeper than 2:1,
an active soil pressure of 40 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 Expansion Index of less than 50.
18. Unrestrained walls are those that are allowed to rotate more than 0.001H at the top of the
wall. Where walls are restrained from movement at the top, an additional uniform pressure
of 7H psf (where H equals the height of the wall in feet) should be added to the above active
soil pressure.
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Project No. 05252-12-01
January 14, 1994
fn 19. All retaining walls should be provided with a drainage system adequate to prevent the buildup
of hydrostatic forces. The need for waterproofing and the type of materials should be
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L determined by others. The use of drainage openings through the base of the wall (weep
p, . holes, etc.) is acceptable, provided that care is taken not to bury the openings and water
to emanating therefrom will not be a nuisance. The above recommendations assume a properly
p*compacted granular (Expansion Index less than 50) backfill material with no hydrostatic
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forces or imposed surcharge load. A typical retaining wall detail is presented on Figure 3.
^ If conditions different than those described are anticipated, or if specific drainage details are
T* desired, Geocon Incorporated should be contacted for additional recommendations.
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t, 20. In general, wall foundations having a minimum depth and width of one foot may be designed
^ for an allowable soil bearing pressure of 2.000 psf, provided the soil within 3 feet below the
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base of the wall has an Expansion Index of less than 90. The proximity of the foundation to
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^ the top of a slope steeper than 3:1 could impact the allowable soil bearing pressure.
r- Therefore, Geocon Incorporated should be consulted where such a condition is anticipated.
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*"21. For resistance to lateral loads, an allowable passive earth pressure equivalent to a fluidfci
pp, density of 300 pcf is recommended for footings or shear keys poured neat against properly
compacted granular fill soils or undisturbed natural soils. The allowable passive pressure
M assumes a horizontal surface extending at least 5 feet or three times the surface generating
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the passive pressure, whichever is greater. The upper 12 inches of material not protected by
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Project No. 05252-12-01
January 14, 1994
floor slabs or pavement should not be included in the design for lateral resistance. 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.
Site Drainage and Moisture Protection
22. The provisions and maintenance of adequate site drainage and moisture protection of
supporting soils is an important design consideration. Foundation recommendations contained
herein assume proper site drainage will be established and maintained.
23. Under no circumstances should water be allowed to pond adjacent to footings. The site
should be graded such that surface drainage flow is directed away from structures and into
swales or other controlled drainage facilities.
Grading and Foundation Plan Review
24. Geocon Incorporated should review the grading and foundation plans prior to final design
submittal to determine if additional analysis or recommendations are required.
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Project No. 05252-12-01
January 14, 1994
^ LIMITATIONS AND UNIFORMITY OF CONDITIONS
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i* 1. The recommendations of this report pertain only to the site investigated and are based upon
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the assumption that the soil conditions do not deviate from those disclosed in the
^ investigation. If any variations or undesirable conditions are encountered during construction,
*» or if the proposed construction will differ from that anticipated herein, Geocon Incorporated
should be notified so that supplemental recommendations can be given. The evaluation or
. identification of the potential presence of hazardous or corrosive materials was not part of the
scope of services provided by Geocon Incorporated.
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2. This report is issued with the understanding that it is the responsibility of the owner, or of
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his representative, to ensure that the information and recommendations contained herein are
b brought to the attention of the architect and engineer for the project and incorporated into the
^" plans, and the necessary steps are taken to see that the contractor and subcontractors carry
out such recommendations in the field.
^" 3. 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 be due to natural
L processes or the works of man on this or adjacent properties. In addition, changes in
m 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
9"L 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.
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Li PROJECT No. 05252-12-01
WALL FOOTING
CONCRETE 3LA8
SANDS
VISOUEEN
.FOOTING *
WIDTH
PAD GRADE
NO SCALE
COLUMN FOOTING
CONCRETE SLAB
SANDS -<r'Wi,.5iiVf.
V1SQUEEN
six
01 UJPlo
FOOTING WIDTH NO SCiUE
* SEE REPORT FOR FOUNDATION WIDTH AND DEPTH RECOMMENDATIONS
WALL / COLUMN FOOTING DIMENSION DETAIL
DATE AND OLIVE SUBDIVISION
CARLSBAD, CALIFORNIA
FIGURE 2
PROJECT No. 05252-12-01
APPROVED FILTER FABRIC
• OPEN QRAOCD l" MAX. AOORE3ATC
5' MAX.
*•* • /-"viL—r-i"1*—4"OIA, PERFORATED PVC PIP€
'AfV.^5 L 1 N1N. !cz%FAU.TOAPPROVEDOUTLET
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PROPOSED FOOTING
NO SCALE
NOTES:
1. Prefabricated drainage panels such as Miradrain 7000 or equivalent
may be used in lieu of placing gravel to a height of 2/3 the total wall
height.
2. Drain should be uniformly sloped and must lead to a positive gravity
outlet or to a sump where water can be removed by pumping.
RETAINING WALL DRAINAGE DETAIL
DATE AND OLIVE SUBDIVISION
CARLSBAD, CALIFORNIA
FIGURE 3
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_ APPENDIX A
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Project No. 05252-12-01
January 14, 1994
APPENDIX A
FIELD INVESTIGATION
The field investigation was performed on January 7, 1994, and consisted of the excavation of 5 small-
diameter borings. The approximate locations of the borings are shown on Figure 1.
The small-diameter borings were advanced to depths of 16 feet below existing grade using an
Ingersol, A-300 truck-mounted drill rig equipped with an eight-inch-diameter hollow stem auger.
Relatively "undisturbed" samples were obtained by driving a 3-inch, split-tube sampler into the
"undisturbed" soil mass with blows from a 140-pound hammer falling 30 inches. The sampler was
equipped with a 1-inch by 23/s-inch-diameter, brass sampler rings to facilitate removal and laboratory
testing. Disturbed bulk samples were also obtained at selected depths.
The soils encountered in the borings were visually examined, classified, and logged. Logs of the
borings are presented on Figures A-l through A-5. The logs depict the soil and geologic conditions
encountered and the depth at which samples were obtained.
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_PROJECTNO. 05252-12-01
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DEPTH
IN
FEET
- 2 -
- 6 -
" —
- 8 -
- 10 -
-
- 12 -
- 14 -
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SAMPLE
NO.
Bl-1 1
CDO
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B1'2 I ;
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Bl-3 • :• : :
Bi-4 •: =
Bi-5 •• ::
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SOIL
CLASS
(USCS)
SP-SC
SP-SM
SP
BORING B 1
ELEV. (MSL.) 40 DATE COMPLETED 1/7/94
EQUIPMENT INGERSOL A-300
MATERIAL DESCRIPTION
TOPSOIL
Loose, damp, dark brown, slightly Clayey fine to
~\ medium SAND with rootlets /"
TERJIACE DEPOSITS
Medium dense, damp to moist, medium brown,
slightly Silty fine to medium SAND with trace
of pinhole
-Becomes orangish to reddish-brown from 5 feet
-Becomes dense, moist, gray and brown, slightly
Silty SAND and trace of pinholes
Becomes medium dense, very moist, light grayish-
A, brown, fine to medium cohesionless SAND f
BORING TERMINATED AT 16 FEET
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28
46
39
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Figure A-l Log of Boring B 1, page 1 of 1 DOS
SAMPLE SYMBOLS D ... SAMPLING UNSUCCESSFUL C ... STANDARD PENETRATION TEST • ... DRIVE SAMPLE (UNDISTURBED)
... DISTURBED OR BAG SAMPLE CHUNK SAMPLE I ... UATER TABLE OR SEEPAGE
NOTE; THE LOG OF SUBSURFACE CONDITIONS SHOUN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE
DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES.
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PROJECT NO. 05252-12-01P*i
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DEPTH
IN
FEET
- 2 -
-
- 4- -
- f\ -
- 8 -_
1U
- 12 -
- 14 -
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SAMPLE
NO.
1
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B2-1 I ;
B2-2 IT ;
B2-3 I ••/•y.
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B2-4 I ;:;:•
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SOIL
CLASS
(USCS)
SP-SM
SM
SP-SM
SP-SC
SP-SW
BORING B 2
ELEV. (MSL.) 37 DATE COMPLETED 1/7/94
EQUIPMENT INGERSOL A-300
MATERIAL DESCRIPTION
TOPSOIL
\ Loose, damp to moist, reddish-brown, slightly [
\ Silty fine to medium SAND /
TERRACE DEPOSITS
Medium dense, damp, dark reddish-brown, Silty
fine to medium SAND
Becomes moist, medium reddish to orangish-brown,
slightly Silty fine to medium SAND
Becomes dense, moist, interbedding of reddish-
brown, slightly Clayey fine to medium SAKE and
gray cohesionless fine to medium SAND
Very dense, moist to wet, very light grayish-brown,
1 very fine to fine cohesionless SAND interbedding /
\ with white fine to very coarse sand with little I
\ gravel /
BORING TERMINATED AT 16 FEET
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^~ HgftS
0.0^
41
22
41
58
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go
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126.1
114.0
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6.7
7.3
Figure A-2 Log of Boring B 2, page 1 of 1 DOS
SAMPLE SYMBOLS D ... SAMPLING UNSUCCESSFUL C ... STANDARD PENETRATION TEST
... DISTURBED OR BAG SAMPLE ... CHUNK SAMPLE
... DRIVE SAMPLE (UNDISTURBED)
... WATER TABLE OR SEEPAGE
fa NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE
DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES.
PROJECT NO. 05252-12-01
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DEPTH
IN
- 2 -
- f, -
"* —
- 8 -
- 10 -_ _
- 12 -
- 14 -
H lo
SAMPLE
NO.
B3-1
B3-2
B3-3
B3-4
B3-5
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ooro
SOIL
CLASS
SM
SM
SP-SM
sw
BORING B 3
ELEV. (MSL.) 39 DATE COMPLETED 1/7/94
EQUIPMENT INGERSOL A-300
MATERIAL DESCRIPTION
TOPSOIL
"\ Loose, damp, dark reddish-brown, Silty fine to f
\ medium SAHD with some rootlets /
TERRACE DEPOSITS
Medium dense, damp, reddish-brown, Silty to
slightly silty fine to medium SAND with little
pinholes
Becomes medium dense moist, reddish- brown,
slightly Silty fine to medium SAND
-Becomes dense, moist at 10 feet
Becomes very dense, moist, very light grayish-
"\ brown, very fine to medium cohesionless SAND /
BORING TERMINATED AT 16 FEET
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30
35
47
65
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p Figure A-3 Log of Boring B 3f page 1 of 1 DOS
SAMPLE SYMBOLS D ... SAMPLING UNSUCCESSFUL C ... STANDARD PENETRATION TEST
... DISTURBED OR BAG SAMPLE ... CHUNK SAMPLE
... DRIVE SAMPLE (UNDISTURBED)
... WATER TABLE OR SEEPAGE
NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE
DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES.
PROJECT NO. 05252-12-01
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BORING B 4
ELEV. (MSL.) 41 DATE COMPLETED 1/7/94
EQUIPMENT INGERSOL A-300
MATERIAL DESCRIPTION
TOPSOIL
"V Loose, damp, dark reddish-brown, fine to medium f
\ Silty SAND with some rootlets /
TERRACE DEPOSITS
Dense, damp, reddish to orangish-brown, fine to
medium Silty SAND.
Becomes dense, moist, orangish-brown, fine to
medium slightly Silty SAND
Becomes very dense, moist, orangish-brown, fine to
\ medium SAND /
BORING TERMINATED AT 16 FEET
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Figure A-4 Log of Boring B 4, page 1 of 1 DOS
SAMPLE SYMBOLS D... SAMPLING UNSUCCESSFUL E... STANDARD PENETRATION TEST
... DISTURBED OR BAG SAMPLE ... CHUNK SAMPLE
... DRIVE SAMPLE (UNDISTURBED)
... WATER TABLE OR SEEPAGE
to MOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREOM APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE
DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES.
PROJECT NO. 05252-12-01
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BORING B 5
ELEV. (MSL.) 39 DATE COMPLETED 1/7/94
EQUIPMENT INGERSOL A-300
MATERIAL DESCRIPTION
TOPSOIL
"\ Loose, damp, reddish- brown, Clayey fine to medium [
\ SAND /
TERRACE DEPOSITS
Very dense, dry to damp, reddish- brown, slightly
Clayey fine to medium SAND
-Becomes dense, moist, orangish-brown
-Becomes dense, moist, medium reddish-brown
Very dense, moist, very light yellowish-brown,
"\ medium to coarse SAND with some rounded gravel f
\ 1/4" to 1/2" diameter /
BORING TERMINATED AT 16 FEET
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p Figure A-5 Log of Boring B 5, page 1 of 1 DOS
SAMPLE SYMBOLS D ... SAMPLING UNSUCCESSFUL D ... STANDARD PENETRATION TEST
... DISTURBED OR BAG SAMPLE ... CHUNK SAMPLE
... DRIVE SAMPLE (UNDISTURBED)
... UATER TABLE OR SEEPAGE
NOTE: THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY AT THE SPECIFIC BORING OR TRENCH LOCATION AND AT THE
DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES.
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APPENDIX B
Project No. 05252-12-01
January 14, 1994
APPENDIX B
LABORATORY TESTING
Laboratory tests were performed in accordance with generally accepted test methods of the American
Society for Testing and Materials (ASTM) or other suggested procedures. Selected samples were
tested for their maximum dry density and optimum moisture content, in-place density, moisture
content, expansion and consolidation characteristics. The results of these tests are summarized on
Tables B-I through B-III and Figure B-l. The results of in-place density and moisture content are
shown on the boring logs, Figures A-l through A-5.
Project No. 05252-12-01
January 14, 1994
TABLE B-I
SUMMARY OF DIRECT SHEAR TEST RESULTS
ASTM D1557-91
Sample
No.
Maximum
Dry Density
(pcf)
Optimum
Moisture
Content
(% Dry Weight)
Unit
Cohesion
(psf)
Angle of
Shear
Resistance
(degrees)
Bl-2*122.8 7.8 800 20
*Sample was remolded to 90 percent of maximum density at near optimum
moisture content.
TABLE B-II
SUMMARY OF LABORATORY MAXIMUM DRY DENSITY
AND OPTIMUM MOISTURE CONTENT TEST RESULTS
ASTM D1557-91
Sample
No.Description
Maximum
Dry Optimum
Density Moisture Content
(pcf) (% Dry Weight)
Bl-2 Brown, fine to medium, slightly Silty SAND 136.5 7.8
Project No. 05252-12-01
January 14, 1994
TABLE B-III
SUMMARY OF LABORATORY EXPANSION INDEX TEST RESULTS
Moisture Content
Before After
Test Test Dry Density
Sample No. (%) (%) (pcf) Expansion Index
Bl-2 5.8 13.9 127.2 0
PROJECT NO. 05252-12-01
PERCENT CONSOLIDATION«*>•* *- i i?ro <scocn**ru<s)r\>.fcSAMPLE NO. B2-2
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APPLIED PRESSURE (ksf)
Initial Dry Density fpcf) ! 114.0
Initial Water Content (%) 1,3
Initial Saturation (%) 42.8
Sample Saturated at (ksf) 0.5
CONSOLIDATION CURVE
DATE AND OLIVE SUBDIVISION
SAN DIEGO, CALIFORNIA
DOS Figure B-l
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APPENDIX C
APPENDIX C
RECOMMENDED GRADING SPECIFICATIONS
FOR
DATE AND OLIVE SUBDIVISION
CARLSBAD, CALIFORNIA
PROJECT NO. 05252-12-01
RECOMMENDED GRADING SPECIFICATIONS
1 GENERAL
1.1 These Recommended Grading Specifications shall be used in conjunction with the
Geotechnical Report for the project prepared by Geocon Incorporated. The recom-
mendations contained in the text of the Geotechnical Report are a pan of the earthwork
and grading specifications and shall supersede the provisions contained hereinafter in
the case of conflict.
1.2 Prior to the commencement of grading, a geotechnical consultant (Consultant) shall be
employed for the purpose of observing earthwork procedures and testing the fills for
substantial conformance with the recommendations of the Geotechnical Report and
these specifications. It will be necessary that the Consultant provide adequate testing
and observation services so that he may determine that, in his opinion, the work was
performed in substantial conformance with these specifications. It shall be the
responsibility of the Contractor to assist the Consultant and keep him apprised of work
schedules and changes so that personnel may be scheduled accordingly.
1.3 It shall be the sole responsibility of the Contractor to provide adequate equipment and
methods to accomplish the work in accordance with applicable grading codes or agency
ordinances, these specifications and the approved grading plans. If, in the opinion of
the Consultant, unsatisfactory conditions such as questionable soil materials, poor
moisture condition, inadequate compaction, adverse weather, and so forth, result in a
quality of work not in conformance with these specifications, the Consultant will be
empowered to reject the work and recommend to the Owner that construction be
stopped until the unacceptable conditions are corrected.
DEFINITIONS
2.1 Owner shall refer to the owner of the property or the entity on whose behalf the
grading work is being performed and who has contracted with the Contractor to have
grading performed.
2.2 Contractor shall refer to the Contractor performing the site grading work.
2.3 Civil Engineer or Engineer of Work shall refer to the California licensed Civil
Engineer or consulting firm responsible for preparation of the grading plans, surveying
and verifying as-graded topography.
2.4 Consultant shall refer to the soil engineering and engineering geology consulting
firm retained to provide geotechnical services for the project.
2.5 Soil Engineer shall refer to a California licensed Civil Engineer retained by the
Owner, who is experienced in the practice of geotechnical engineering. The Soil
Engineer shall be responsible for having qualified representatives on-site to observe and
test the Conn-actor's work for conformance with these specifications.
2.6 Engineering Geologist shall refer to a California licensed Engineering Geologist
retained by the Owner to provide geologic observations and recommendations during
the site grading.
2.7 Geotechnical Report shall refer to a soil report (including all addendums) which may
include a geologic reconnaissance or geologic investigation that was prepared
specifically for the development of the project for which these Recommended Grading
Specifications are intended to apply.
MATERIALS
3.1 Materials for compacted fill shall consist of any soil excavated from the cut areas or
imported to the site that, in the opinion of the Consultant, is suitable for use in
construction of fills. In general, fill materials can be classified as soil fills, soil-rock
fills or rock fills, as defined below.
3.1.1 Soil fills are defined as fills containing no rocks or hard lumps greater than 12
inches in maximum dimension and containing at least 40 percent by weight of
material smaller than 3/4 inch in size.
3.1.2 Soil-rock fills are defined as fills containing no rocks or hard lumps larger than
4 feet in maximum dimension and containing a sufficient matrix of soil fill to
. allow for proper compaction of soil fill around the rock fragments or hard
lumps as specified in Paragraph 6.2. Oversize rock is defined as material
greater than 12 inches.
3.1.3 Rock fills are defined as fills containing no rocks or hard lumps larger than 3
feet in maximum dimension and containing little or no fines. Fines are defined
as material smaller than 3/4 inch in maximum dimension. The quantity of fines
shall be less than approximately 20 percent of the rock fill quantity.
3.2 Material of a perishable, spongy, or otherwise unsuitable nature as determined by the
Consultant shall not be used in fills.
3.3 Materials used for fall, either imported or oil-site, shall not contain hazardous materials
as defined by the California Code of Regulations, Title 22, Division 4, Chapter 30,
Articles 9 and 10; 40CFR; and any other applicable local, state or federal laws. The
Consultant shall not be responsible for the identification or analysis of the potential
presence of hazardous materials. However, if observations, odors or soil discoloration
cause Consultant to suspect the presence of hazardous materials, the Consultant may
request from the Owner the termination of grading operations within the affected area.
^" Prior to resuming grading operations, the Owner shall provide a written report to the
•> Consultant indicating that the suspected materials are not hazardous as defined by
applicable laws and regulations.
[
3.4 The outer 15 feet of soil-rock fill slopes, measured horizontally, should be composed
of properly compacted soil fill materials approved by the Consultant. Rock fill may
extend to the slope face, provided that the slope is not steeper than 2:1
(horizontal:vertical) and a soil layer no thicker than 12 inches is track-walked onto the
P. face for landscaping purposes. This procedure may be utilized, provided it is
L acceptable to the governing agency, Owner and Consultant.
p» 3.5 Representative samples of soil materials to be used for fill shall be tested in the
^ laboratory by the Consultant to determine the maximum density, optimum moisture
content, and, where appropriate, shear strength, expansion, and gradation
r* characteristics of the soil.
b.
3.6 During grading, soil or groundwater conditions other than those identified in the
r* Geotechnical Report may be encountered by the Contractor. The Consultant shall be
» notified immediately to evaluate the significance of the unanticipated condition.
r
^ 4 CLEARING AND PREPARING AREAS TO BE FILLED
I*4.1 Areas to be excavated and filled shall be cleared and grubbed. Clearing shall consist
of complete removal above the ground surface of trees, stumps, brush, vegetation,
IN man-made structures and similar debris. Grubbing shall consist of removal of stumps,
L roots, buried logs and other unsuitable material and shall be performed in areas to be
graded. Roots and other projections exceeding 1-1/2 inches in diameter shall be
removed to a depth of 3 feet below the surface of the ground. Borrow areas shall be
grubbed to the extent necessary to provide suitable fill materials.
^ 4.2 Any asphalt pavement material removed during clearing operations should be properly
b'disposed at an approved off-site facility. Concrete fragments which are free of
reinforcing steel may be placed in fills, provided they are placed in accordance with
P Section 6.2 or 6.3 of this document.
b
PI
b
43 After clearing and grubbing of organic matter or other unsuitable material, loose
or porous soils shall be removed to the depth recommended in the Geotechnical
Report. The depth of removal and compaction shall be observed and approved
by a representative of the Consultant The exposed surface shall then be plowed
or scarified to a minimum depth of 6 inches and until the surface is free from
uneven features that would tend to prevent uniform compaction by the equipment
to be used.
4.4 Where the slope ratio of the original ground is steeper than 6:1
(horizontal-vertical), or where recommended by the Consultant, the original
ground should be benched in accordance with the following illustration.
TYPICAL BENCHING DETAIL
FINISH CRAOE
FINISH SLOPE SUflFACS
ftCMOVC
•T SOIL
ae SUCH
StOUOMNQ OR SLJOI
OOC3 MOT OCCUM
IMOTE I wire ^'
MO SCiL£
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F
fc
NOTES: (1) Key width "B" should be a minimum of 10 feet wide, or
sufficiently wide to permit complete coverage with the
compaction equipment used. The base of the key should be
graded horizontal, or inclined slightly into the natural slope.
(2) The outside of the bottom key should be below the topsail
or unsuitable surnciai material and at least 2 feet into dense
formational material Where hard rock is exposed in the bottom
of the key, the depth and configuration of the key may be
modified as approved by the Consultant.
4.5 After areas to receive fill have been cleared, plowed or scarified, the surface should
be disced or bladed by die Contractor until it is uniform and tree from large clods.
The area should then be moisture conditioned to achieve the proper moisture content,
and compacted as recommended in Section 6.0 of these specifications.
5 COMPACTION EQUIPMENT
PL 5.1 Compaction of soil or soil-rock fill shall be accomplished by sheepsfoot or segmented-
steel wheeled rollers, vibratory rollers, multiple-wheel pneumatic-tired rollers, or other
p, . types of acceptable compaction equipment. Equipment shall be of such a design that
it will be capable of compacting the soil or soil-rock fill to the specified relative
compaction at the specified moisture content.
: 5.2 Compaction of rock fills shall be performed in accordance with Section 6.3.
r 6 PLACING, SPREADING AND COMPACTION OF FILL MATERIAL
L.
6. 1 Soil fill, as defined hi Paragraph 3.1.1, shall be placed by the Contractor in accordance
T" with the following recommendations:
t.
6.1.1 Soil fill shall be placed by the Contractor in layers that, when compacted,
^ should generally not exceed 8 inches. Each layer shall be spread evenly and
k. shall be thoroughly mixed during spreading to obtain uniformity of material and
moisture in each layer. The entire fill shall be constructed as a unit in nearly
r* level lifts. Rock materials greater than 12 inches in maximum dimension shall
^ be placed in accordance with Section 6.2 or 6,3 of these specifications.
*• 6. 1.2. In general, the soil fill shall be compacted at a moisture content at or above the
y optimum moisture content as determined by ASTM D1557-91.
*• 6. 1.3 When the moisture content of soil fill is below that specified by the Consultant,
^ • water shall be added by the Contractor until the moisture content is in the range
specified.
^>
L 6.1.4 When the moisture content of the soil fill is above the range specified by the
Consultant or too wet to achieve proper compaction, the soil fill shall be aerated
_ by the Contractor by Wading/mixing, or other satisfactory methods until the
-, moisture content is within the range specified.
6.1.5 After each layer has been placed, mixed, and spread evenly, it shall be
thoroughly compacted by the Contractor to a relative compaction of at least 90
percent. Relative compaction is defined as the ratio (expressed in percent) of
the in-place dry density of the compacted fill to the maximum laboratory dry
density as determined in accordance with ASTM D 1557-91. Compaction shall
™ be continuous over the entire area, and compaction equipment shall make
sufficient passes so that the specified minimum density has been achieved
throughout the entire fill.
C
6.1.6 Soils having an Expansion Index of greater than 50 may be used in fills if
placed at least 3 feet below finish pad grade and should be compacted at a
moisture content generally 2 to 4 percent greater than the optimum moisture
content for the material.
6.1.7 Properly compacted soil fill shall extend to the design surface of fill slopes. To
achieve proper compaction, it is recommended that fill slopes be over-built by
at least 3 feet and then cut to the design grade. This procedure is considered
preferable to track-walking of slopes, as described hi the following paragraph.
6.1.8 As an alternative to over-building of slopes, slope faces may be back-rolled with
a heavy-duty loaded sheepsfoot or vibratory roller at maximum 4-foot fill height
intervals. Upon completion, slopes should then be track-walked with a D-8
dozer or similar equipment, such that a dozer track covers all slope surfaces at
least twice.h.
6.2 Soil-rock fill, as defined in Paragraph 3.1.2, shall be placed by the Contractor in
accordance with the following recommendations:
W
6.2.1 Rocks larger than 12 inches but less than 4 feet in maximum dimension may be
^ incorporated into the compacted soil fill, but shall be limited to the area
^ • measured 15 feet minimum horizontally from the slope face and 5 feet below
finish grade or 3 feet below the deepest utility, whichever is deeper.^
h. 6.2.2 Rocks or rock fragments up to 4 feet in maximum dimension may either be
individually placed or placed in windrows. Under certain conditions, rocks or
*• rock fragments up to 10 feet in maximum dimension may be placed using
hw similar methods. The acceptability of placing rock materials greater than 4 feet
in maximum dimension shall be evaluated during grading, as specific cases arise
r~ and shall be approved by the Consultant prior to placement.
k.6.2.3 For individual placement, sufficient space shall be provided between rocks to
r- allow for passage of compaction equipment.
C 6.2.4 For windrow placement, the rocks should be placed in trenches excavated in
P- properly compacted soil fill. Trenches should be approximately 5 feet wide and
. 4 feet deep in maximum dimension. The voids around and beneath rocks
should be filled with approved granuiar soil having a Sand Equivalent of 30 or
_ greater and should be compacted by flooding. Windrows may aiso be placed
utilizing an "open-face" method in lieu of the trench procedure, however, this
method should first be approved by the Consultant.
6.2.5 Windrows should generally be parallel to each other and may be placed either
parallel to or perpendicular to the face of the slope depending on the site
geometry. The minimum horizontal spacing for windrows shall be 12 feet
cemer-to-center with a 5-foot stagger or offset from lower courses to next
** overlying course. The minimum vertical spacing between windrow courses
shall be 2 feet from the top of a lower windrow to the bottom of the next higher
windrow.
IB 6.2.6 All rock placement, fill placement and flooding of approved granular soil in the
•• windrows must be continuously observed by the Consultant or his
^ representative.
p 6.3 Rock fills, as defined hi Section 3.1.3, shall be placed by the Contractor in accordance
u with the following recommendations:
p 6.3.1 The base of the rock fill shall be placed on a sloping surface (minimum slope
L of 2 percent, maximum slope of 5 percent). The surface shall slope toward
suitable subdrainage outlet facilities. The rock fills shall be provided with
subdrains during construction so that a hydrostatic pressure buildup does not
develop. The subdrains shall be permanently connected to controlled drainage
* facilities to control post-construction infiltration of water.
: 6.3.2 Rock fills shall be placed in lifts not exceeding 3 feet. Placement shall be by
" rock trucks traversing previously placed lifts and dumping at the edge of the
currently placed lift. Spreading of the rock fill shall be by dozer to facilitate
** seating of the rock. The rock fill shall be watered heavily during placement.
t> Watering shall consist of water trucks traversing in front of the current rock lift
face and spraying water continuously during rock placement. Compaction
?* equipment with compactive energy comparable to or greater than that of a
U • 20-ton steel vibratory roller or other compaction equipment providing suitable
energy to achieve the required compaction or deflection as recommended in
^ Paragraph 6.3.3 shall be utilized. The number of passes to be made will be
ta, determined as described in Paragraph 6.3.3. Once a rock fill lift has been
covered with soil fill, no additional rock fill lifts will be permitted over the soil
*• fill.
bi
6.3.3 Plate bearing tests, in accordance with ASTM Dl 196-64, may be performed in
p both the compacted soil fill and in the rock fill to aid in determining the number
^ of passes of the compaction equipment to be performed. If performed, a
minimum of three plate bearing tests shall be performed in the properly
P* .compacted soil fill (minimum relative compaction of 90 percent). Plate bearing
ta • tests shall then be performed on areas of rock fill having two passes, four passes
and six passes of the compaction equipment, respectively. The number of
r-. passes required for the rode fill shall be determined by comparing the results
of the plate bearing tests for the soil fill and the rock fill and by evaluating the
deflection variation with number of passes. The required number of passes of
p, the compaction equipment will be performed as necessary until the plate bearing
: deflections are equal to or less than that determined for the properly compacted
soil fill. In no case will the required number of passes be less than two.
p*6.3.4 A representative of the Consultant shall be present during rock fill operations
™ to verify that the minimum number of "passes" have been obtained, that water
is being properly applied and that specified procedures are being followed. The
actual number of plate bearing tests will be determined by the Consultant during
*• grading. In general, at least one test should be performed for each
approximately 5,000 to 10,000 cubic yards of rock fill placed.
m 6.3.5 Test pits shall be excavated by the Contractor so that the Consultant can state
*» that, in his opinion, sufficient water is present and that voids between large
. rocks are properly filled with smaller rock material, In-place density testing
will not be required hi the rode fills.
^
L 6.3.6 To reduce the potential for "piping" of fines into the rock fill from overlying
soil fill material, a 2-foot layer of graded filter material shall be placed above
m the uppermost lift of rock fill. The need to place graded filter material below
the rock should be determined by the Consultant prior to commencing grading.
The gradation of the graded filter material will be determined at the time the
_ rock fill is being excavated. Materials typical of the rock fill should be
submitted to the Consultant in a timely manner, to allow design of the graded
** filter prior to the commencement of rock fill placement.
f*6.3.7 All rock fill placement shall be continuously observed during placement by
*• representatives of the Consultant.
OBSERVATION AND TESTING
7.1 The Consultant shall be the Owners representative to observe and perform tests during
clearing, grubbing, filling and compaction operations. In general, no more than 2 feet
in vertical elevation of soil or soil-rock fill shall be placed without at least one field
density test being performed within that interval. In addition, a minimum of one field
density test shall be performed for every 2,000 cubic yards of soil or soil-rock fill
placed and compacted.
7.2 The Consultant shall perform random field density tests of the compacted soil or
soil-rock fill to provide a basis for expressing an opinion as to whether the fill material
is compacted as specified. Density tests shall be performed in the compacted materials
below any disturbed surface. When these tests indicate that the density of any layer
of fill or portion thereof is below that specified, the particular layer or areas
represented by the test shall be reworked until the specified density has been achieved.
7.3 During placement of rock fill, the Consultant shall verify that the minimum number of
passes have been obtained per the criteria discussed in Section 6.3.3. The Consultant
shall request the excavation of observation pits and may perform plate bearing tests on
the placed rock fills. The observation pits will be excavated to provide a basis for
expressing an opinion as to whether the rode fill is properly seated and sufficient
moisture has been applied to the material. If performed, plate bearing tests will be
performed randomly on the surface of the most-recently placed lift. Plate bearing tests
will be performed to provide a basis for expressing an opinion as to whether the rock
fill is adequately seated. The maximum deflection in the rock fill determined in
Section 6.3.3 shall be less than the maximum deflection of the properly compacted soil
fill. When any of the above criteria indicate that a layer of rock fill or any portion
thereof is below that specified, the affected layer or area shall be reworked until the
rock fill has been adequately seated and sufficient moisture applied.
7.4 A settlement monitoring program designed by the Consultant may be conducted in
areas of rock fill placement. The specific design of the monitoring program shall be
as recommended in the Conclusions and Recommendations section of the project
Geotechnical Report or in the final report of testing and observation services performed
during grading.
7.5 The Consultant shall observe the placement of subdrains, to verify that the drainage
devices have been placed and constructed in substantial conformance with project
specifications.
7.6 Testing procedures shall conform to the following Standards as appropriate:
7.6.1 SoU and Soil-Rock Fills:
7.6.1.1 Field Density Test, ASTM D1556-82, Density of Soil In-Place By the
Sand-Cone Method.
7.6.1.2 Field Density Test, Nuclear Method, ASTM D2922-81, Density of
Soil and Soil-Aggregate In-Place by Nuclear Methods (Shallow
Depth).
•7.6.1.3 Laboratory Compaction Test, ASTM D1557-91, Moisture-Density
Relations of Soils and Soil-Aggregate Mixtures Using 10-Pound
Hammer and 18-Inch Drop.
7.6.1.4 Expansion Index Test, Uniform Building Code Standard 29-2,
Expansion Index Test.
7.6.2 Rock Fills:
7.6.2.1 Field Plate Bearing Test, ASTM D1196-64 (Reapproved 1977)
Standard Method for Nonrepresentative Static Plate Load Tests of
Soils and Flexible Pavement Components, For Use in Evaluation and
Design of Airport and Highway Pavements.
8 PROTECTION OF WORK
8.1 During construction, the Contractor shall properly grade all excavated surfaces to
provide positive drainage and prevent ponding of water. Drainage of surface water
shall be controlled to avoid damage to adjoining properties or to finished work on the
site. The Contractor shall take remedial measures to prevent erosion of freshly graded
areas until such time as permanent drainage and erosion control features have been
installed. Areas subjected to erosion or sedimentation shall be properly prepared in
accordance with the Specifications prior to placing additional fill or structures.
8.2 After completion of grading as observed and tested by die Consultant, no further
excavation or filling shall be conducted except in conjunction with the services of the
Consultant.
9 CERTIFICATIONS AND FINAL REPORTS
IP"
^ 9.1 Upon completion of the work, Contractor shall famish Owner a certification by the
Civil Engineer stating that the lots and/or building pads are graded to within 0.1 foot
p. vertically of elevations shown on the grading plan and that all tops and toes of slopes
I are within 0.3 foot horizontally of the positions shown on the grading plans. After
installation of a section of subdrain, the project Civil Engineer should survey its
p, location and prepare an as-built plan of the subdrain location. The project Civil
. Engineer should verify the proper outlet for the subdrains and the Contractor should
ensure that the drain system is free of obstructions.
9.2 The Owner is responsible for furnishing a final as-graded soil and geologic report
™ satisfactory to the appropriate governing or accepting agencies. The as-graded report
should be prepared and signed by a California licensed Civil Engineer experienced in
geotechnical engineering and by a California Certified Engineering Geologist,
fc> indicating that the geotechnical aspects of the grading were performed in substantial
conformance with the Specifications or approved changes to the Specifications.
Gcocoo Iflcorpomerf Form. Revision tjaos: OS/93