HomeMy WebLinkAboutCT 82-16; THE VILLAS AT CALAVERA HILLS VILLAGE J; GEOTECHNICAL INVESTIGATION; 1983-04-28ti S h'
Woodward-Clyde Consultants
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GEOTECHNICAL INVESTIGATION
FOR THE PROPOSED
BATIQUITOS POINTE
CARLSBAD, CALIFORNIA
I' Prepared, for '
Saminis Properties
5030 Camino de la Siesta
San Diego, California 92108
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3467 Kurtz Street
San Diego, California 92110 Woodward.Cyde Consultants
(619) 224-2911
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April 28, 1983
Project.No. 53147K-SIO1
Sammis Properties
5030 Camino de la Siesta
San Diego, California 92108
Attention: Mr. Fred Vaughn
GEOTECHNICAL INVESTIGATION
FOR THE PROPOSED
BATIQUITOS POINTE
CARLSBAD, CALIFORNIA
Gentlemen:
We are pleased to provide the accompanying report, which
presents the results of our geotechnical investigation for the
subject project. This study was performed in accordance with
our proposal dated March 17, 1983.
The report presents our conclusions and recommendations
pertaining to the pro ject, as well as the results of our field
explorations and laboratory tests.
Our engineer assigned to this project is Mr. Buck Buchanan. If
you have any questions or if we can be of further service,
please give us a call.
Very truly yours,
WOODWARD-CLYDE CONSULTANTS
CIc/
Buck Buchanan
R.E. 26876
BB/AA/BRS/fla
(6)
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Consulting Engineers. Geologists
and Environmental Scientists
Offices in Other Principal Cites
- Project.No. 5314.7K-SI01. S Woodward.Cyde Consultants
TABLE OF CONTENTS
Page
PURPOSE AND SCOPE OF INVESTIGATION 1.
DESCRIPTION OF THE PROJECT 2
FIELD AND LABORATORY INVESTIGATIONS . 3
SITE CONDITIONS 3:
Geologic Setting 3
S Surface Conditions 3
Subsurface Soils . . 4
Structure . 4
• Ground Water . . . 5
S
DISCUSSIONS, CONCLUSIONS AND RECOMMENDATIONS
.
. 5
. Potential Geologic Hazards 5
Faulting and Ground Breakage 5
• Liquefaction • 6
Site Preparation 6
Excavation Characteristics - .7
Drainage . 7
• Foundations . •
Floor Slabs •
. 8 •. •
Slope Stability Analysis S 9
Proposed Construction Slopes
•
5 9
5 S Existing Bluff • 5 10 5
Retaining Walls and Lateral Loads 10
UNCERTAINTY AND LIMITATIONS Ii
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• S 5
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TABLE OF CONTENTS (Continued)
Page
FIGURES
1'. Site Plan
APPENDIXES '
• A. Field Investigation A-i
• ' Figures •
A-i. Key to Logs
A-2 through A-9. Logs of Test Borings
Laboratory Tests B-i
Figures •
B-i. Grain Size Distribution Curves '•
Guide Specifications for Controlled Fill
•
ATTACHMENT :
Report dated April 21, 1983
• Geologic Stability of Bluff Top Development, •
Batiquitos Pointe, Carlsbad,' California •
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Project. No.. 53147K-SIOl.
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S
, GEOTECHNICAL INVESTIGATION
. . 'FOR THE PROPOSED
• . . . BATIQUITOS POINTE
CARLSBAD,'CALIFORNIA
S PURPOSE AND SCOPE OF INVESTIGATION
This report presents the results of our' geotechnical
investigation at the site of the proposed Batiquitos Pointe
project. . .
S The site is located on the north side of Batiquitos
Lagoon, east of Carlsbad Boulevard,, west of the A.T.&S.F.
railway, and south of Ponto Drive in. Carlsbad, California.
This report has been prepared exclusively for Sammis
• Properties and their consultants for use in evaluating the
property and in project design. This report presents
•
our
conclusions and/or recommendations regarding:
• . 0 The geologic setting of the site
••
•
o Potential geologic hazards •
o General subsurface soil conditions
• . . • General extent of existing, fill soils
• Conditions of areas to receive fill
o Characteristics of proposed fill material' .
o 'Presence and effect of expansive soils .' .
O Depth to water (if within the depths of our
. subsurface investigation)
' Stability of proposed cut and fill slopes '
o Grading and earthwork
o Types and depths of foundations'
'
O Allowable soil bearing pressures •
•
Design pressures for retaining walls
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• In addition, we have evaluated 'the erosion potential of the
on-.site -soils and the bluff-face fronting the lagoon to aidthe•
developer's compliance with Section 30253 of the 1976 Coastal
Act. The results of that portion of our study are reported
• under separate cover.
DESCRIPTION OF THE PROJECT
For our study, we have discussed the proposed project with
• Mr'. Steve Bieri of Sammis Properties and Mr. Patrick O'Day of
O'Day Consultants. We have been provided a copy of the
"Tentative Map of Batiquitos Pointe, Carlsbad Tract No. CT
82-18/CP-214" prepared by .O'Day Consultants dated July 15,
• 1982, revised February 7, 1983. Finish floor elevations of the
buildings and spot design elevations of streets are shown on
these plans. Additionally, we have reviewed work performed by
our firm on a' similar site approximately one-half mile east of
• the subject site.
We understand that the proposed project will include.
subdividing the parcel into 3 lots and an open space easement.
We understand that this investigation is to focus primarily on
' the geotechnical constraints of developing the bluff top, on
Lots 1. and 2 and that site grading and development for this
phase will only be performed on Lot 2. A siltation basin will
be constructed in the open space easement located along the
• south-central portion of the western boundary. , Site grading
will create cut and fill slopes, constructed at maximum
inclinations of 2:1 (horizontal to vertical), to, heights of
less than 15 feet.
• Site improvements will consist 'of nine building pads that
will contain 2 and 3 story structures of Wood frame and masonry
construction and underground. parking. Swimming pools and lined
shallow ponds are also planned. The planned location and
• layout of the major project structures are shown on the Site
Plan (Figures 1 and 1A). '
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'. . . Project No.. 53147K-SIO1. . .
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S FIELD AND LABORATORY INVESTIGATIONS
Our field investigation included making a visual
reconnaissance of the existing surface conditions, evaluating
the erosion potential of the existing bluff, making eight test
S , borings on April 5 and 6, 1983, and obtaining representative.
soil samples. The test borings were advanced to depths ranging
from 13½ to 52½ 'feet. . The locations of the borings are shown
on Figure 1.
• A Key to Logs is presented in Appendix A as Figure Al.
Final logs of the borings' are presented in Appendix . A as
Figures A-2 through A-9. The descriptions on the 'logs are
based on field logs, sample inspection, and laboratory test
• results. Results' of laboratory tests are shown at the
corresponding sample locations on the logs and in Appendix B.
The field investigation and laboratory testing programs' are
discussed in Appendixes A and B.
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SITE CONDITIONS
Geologic Setting . ..
The site lies on a gently westerly sloping, Quaternary
• 'age, marine terrace surface at approximate elevation 50 feet
(MSLD). The relatively horizontally bedded terrace materials
have been deposited on a wavecut platform on the underlying B
member of the Tertiary age Santiago Formation.
S
Surface Conditions
The surface of Lots 1 and 2 appears to be little changed',
from the natural state. This relatively flat terrace surface,
• is currently under cultivation for flowers and is 'subject to
daily irrigation. Lot 3 covers the south-facing 45-foot high
slope at the south end of Lot 2 and extends to the south and
includes the lagoon area and a manmade fill of unknown depth.,
• Two buried telephone trunk cables and a 12-3/4 inch gas
line extend across the property from north to south, generally
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along the west side. The A.T.&S.F. railroad occupies a slot
cut along the eastern site boundary. This railroad cut- is
approximately 25 feet deep at the south end of Lot 2 and
approximately 3 feet deep at the north end of Lot 1. Minor
manmade features on the site include irrigation pipe, fencing.
and roads. No fill soils were observed in our test borings or
on the surface of Lots 1 and 2.
Subsurface Soils . .
The site (Lots 1 and 2) is underlain by from 2 to 4 feet
of slightly porous loose to medium dense, brown, silty medium
to fine sandy topsoil. The topsoil is underlain by 12 to. 20
feet (at least 20 feet at test boring no. 8) of dense to very
dense light brown, silty to clayey sands of the Lindavista
Formation of Quaternary age. The upper half of this interval
(within the proposed grading depth in some areas) contains some
clay and may be moderately expansive. The Lindavista Formation
is underlain by the Santiago Formation of Tertiary age. These
very dense light gray silty sands were encountered in our test
borings onLots 1 and 2 at depths of from 15 to 20 feet below
the natural ground surface, except in test boring 8, where the
contact may be lower due to a filled channel or other erosional
irregularity in the Santiago Formation.
Exposures of Quaternary and Tertiary age sediments on and
near the site exhibit horizontal or nearly horizontal bedding
attitudes; however, accurate dip and strike measurements are -
difficult to make due to cross-bedding in these units. No
evidence of faulting was observed on or near the site during
our field work.
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Ground Water
Our geologic reconnaissance and evaluation of water level
measurements made during two days of test drilling indicates
that the water observed in the boring results in part from
relatively intensive daily irrigation of the flower crop on the
surface. This water tends to percolate down through the
relatively. pervious Lindavista Formation to the relatively
impervious contact with the underlying • Santiago Formation,
where it forms a "perched" water table at an. approximate
elevation of 33 to 36 feet, MSLD.
DISCUSSIONS, CONCLUSIONS AND RECOMMENDATIONS
The discussions, conclusions, and 'recommendations
presented in this report are based on the results of our field
and laboratory studies, analyses, and professional judgment.
Potential Geologic Hazards
Faulting and Ground Breakage
No faulting or evidence for faulting is known for the 0
subject site. A few minor faults have been mapped in the
seacliffs south of the site in the Leucadia area, and in, the
bluffs above Batiquitos. Lagoon, but the closest fault of
significant mapped length i the postulated offshore extension
of the Rose Canyon zone, approximately 5 miles to the
southwest. The closest faulting to the site with recorded
earthquakes of magnitude 4 or greater is associate with the
Elsinore Fault zone' about 25 miles northeast of the site and
the San Clemente Fault zone about 50 miles southwest of the
• ' site. No magnitude 4 or larger earthquakes are associated with
the Rose Canyon Fault or other faults in the general San
Diego-Oceanside coastal area.
Although no known faulting is indicated on the site, it is
• possible that splinter faults or ground fractures may be
encountered in the proposed, excavations. Cut areas should be
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inspected by a geologist during grading and if such features
are encountered, some remedial work or adjustment to the
construction, procedure may be required.
Liquefaction
The geologic units at the site are not recognized, as
having a potential for liquefaction.
• ' Site Preparation
We recommend that the building areas and all fill areas be
cleared of any existing vegetation, trash, and any debris or
rubble. The undesirable materials generated
, during the
• clearing should be disposed of off the site.
We recommend that all porous topsoils, and other natural
loose soils or existing fills within the building areas or
proposed fill areas not removed by planned grading be, excavated
• or scarified as required, replaced, watered, and then
recompacted prior to placing fill or structures. Based on our
field investigation, we anticipate that up to 4 feet of topsoil
may have to be removed. We recommend that the soil engineer
• 'evaluate the actual depth of excavation in the field at the
time of grading. Building areas are generally defined as the
building limits plus a horizontal distance of 5 feet beyond all
settlement-sensitive portions of the building.
• We recommend that the upper 2 'feet of materials in the
fill areas be composed of nonexpansive soils. • Nonexpansive
soils, are defined as granular soils that have a potential swell
of less than 3 percent when recompacted to' 90 percent of
. maximum 'laboratory density at optimum moisture content, placed
under an axial load of 160 psf, and soaked in water. We
recommend that all fill soils be placed between optimum
moisture content and 3 percent above optimum moisture content.
• In our opinion, the formational soils 'on site should
generally be suitable as select structural fill material and
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are considered to be nonexpansive in nature. Occasionally
however, potentially expansive clay layers are encountered
within the sands of the Lindavista formation. Where these
expansive soils are encountered at finish grade they should be
undercut to a maximum depth of 2 feet and replaced with
properly. compacted nonexpansive soils.
We recommend that all earthwork be done in accordance with
the attached Specifications for Controlled Fill (Appendix C).
Excavation Characteristics
Based on the results of the test borings and on our
experience with similar soils, -it is our opinion that most of
the on-site soils can generally be excavated by medium ripping
with conventional excavation equipment. It is anticipated,,
however, that heavy ripping will be required for excavating the
hard cemente,d zones that are usually encountered in the
Lindavista formation.
Drainage
We recommend that positive measures be taken to properly
finish grade each pad after structures and other improvements
are completed so that drainage waters from the pads and
- adjacent properties are directed off the pads and away from
foundations, floor slabs, and slope tops.- Even when these
measures have been taken, experience has shown that a shallow
ground-water or surface-water condition can and may develop in -
areas where no such water condition existed prior to site
development; this is particularly true where a substantial
increase in surface-water infiltration results from landscaping
irrigation. . .
Foundations
Most of the proposed buildings, as presently located, will
be supported on relatively unyielding. formational soils;
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• however, some buildings will be supported partially on
formational and partially on compacted fill. In our opinion,
the proposed structures can be supported on conventional spread
or continuous strip foundations founded on either formational
• soils, properly compacted fill 'soils, or on a combination of.
both.
We recommend that spread or continuous footings placed on
either compacted fill or a combination of compacted fill and
• formational soil be designed using a maximum allowable bearing
capacity of 2,500 psf. Footings founded in only formational
material should be designed using a maximum allowable bearing
capacity of 5,000 psf.
• Continuous footings should have a minimum width of
18 inches and spread footings should have a minimum width of
2 feet. All, footings should be .at least 18 inches, deep
measured from rough finish grade, or in the case of interior
• footings, from finish grade.
A one-third increase in allowable soil bearing pressure
may be used 'for design of footings to resist total load
including wind and seismic forces.
• We recommend that all continuous footings be reinforced
top and bottom with at least one No. 4 reinforcing bar. We
recommend that additional steel be placed in the footings at
cut-fill locations.
• ' Footings should not be located, within 8 feet of the top of
a fill slope or 5 feet of the top of a cut slope. Footings'
located closer than 8 feet (or 5 feet) from the top of a slope
should be extended in depth until the outer bottom edge of'the
• . footing is the required distance (8 or 5 feet) horizontally
from the outside face, of the slope.
Floor Slabs . .
• We recommend that the slab-on-grade floors have a minimum
thickness of 4 inches and that they be nominally reinforced by
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Woodward.aydeConsuftants
C 6. x 6, 10./10 wire mesh placed at the midpoint of the slab.
Slabs supporting heavy loads should be designed for appropriate
loading and usage. We can provide specific design criteria if
this information is desired.
Concrete slabs. should be underlain by 4 inches of sand and
a plastic vapor barrier in those areas where floor coverings
are sensitive to moisture.
Slope Stability Analysis . .
Proposed Construction Slopes
Based on the available grading plans, we estimate the
proposed cut and fill slopes to be on the order of 15 feet high
S (or less) at an inclination of 2:1 (horizontal to vertical).
For this condition, we have performed stability analyses by the
Janbu, method using parameters developed from the results of.
plasticity tests performed on selected samples, the results of
S direct shear . tests performed on representative samples of
similar soils from nearby areas, and our experience in the
general site area. 0
The results of our analyses indicat that 2:1 inclined cut
S and/or fill slopes having maximum heights of 10 feet have
calculated factors of safety for deep-seated failure in excess
of 1.5 for static conditions.
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Stability analyses require using parameters selected from
a range of possible values; thus there is a finite possibility
that slopes hav'ing calculated factors of safety as indicated
above could become unstable'. In our opinion, the probability
of the slopes becoming unstable is low, and it is our
professional judgment that the slopes can be constructed as
'indicated above. We recommend that an engineering geologist
from our firm examine all cut slopes for possible adverse
conditions during grading. 0
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Project No. 53147K-SIO1
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Fill slopes, particularly those constructed at
inclinations steeper than 2:1, are susceptible to shallow slope
sloughing in periods, of rainfall, heavy irrigation, and/or
upsiope runoff. Periodic slope maintenance may be required.
Sloughing can be reduced by backrolling slopes at frequent
intervals. As a minimum, we recommend that fill slopes be
backrolled at maximum 4-foot height intervals. Additionally,
we recommend that all fill slopes be trackwalked so that a
dozer track covers all surfaces at least twice.
Existing Bluff
The stability as well as the erosion potential of the
• existing bluff along the southern boundary of Lot •2 were
evaluated in general accordance with the 1976 Coastal Act,
Section 30253. Our evaluation of existing conditions,
analysis, conclusions, and recommendations were presented in
• separate letter report dated April 21, 1983 (attached)
Retaining Walls and Lateral Loads
We recommend that retaining walls not restrained from
• movenient at the top and required to support lateral earth
pressures due to differential soil height be designed for an
equivalent fluid pressure of 35 pcf. Retaining walls
restrained from movement at the top, such as basement walls,
• should be designed for an equivalent, fluid pressure of 35 pcf
plus a unifOrm lateral pressure of 10H psf (H = the height of
retained earth in feet) . These pressures are 'based on
horizontal backfill surfaces, the use of on-site granular
• ' materials for backfilling the walls, and adequate drainage to
prevent buildup of hydrostatic pressure behind the wall. If
other conditions and/or particular loads, such as adjacent
footings or vehicle' surcharge loads, are to be considered in
•
,
the vicinity of retaining walls, we should be advised so that
additional recommendations can be given as required.
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Project No.. 53147K-SIO1
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To provide resistance for. lateral loads, we recommend that
passive pressure be assumed equivalent to a fluid pressure of
300 pcf for footings and shear keys poured neat against cut
formational soils or properly compacted. fill soils. The upper
12 inches of material in areas not protected by floor slabs or
pavements should not be included in design for passive
resistance to lateral .loads. This lateral pressure is based on
the assumption that the ground surface adjacent to the footing
is nearly horizontal for a minimum distance of 10 feet from the
face of the footing or three times the height of the surface
generating passive pressure, whichever is greater.
In calculation of frictional resistance to lateral loads,
• we recommend using a value of 0.4 as the allowable coefficient
of sliding friction between concrete and the underlying soil.
If combined, frictional and passive lateral resistance are
utilized in design, we recommend using a frictional resistance
• of 0.3.
UNCERTAINTY AND LIMITATIONS
We have observed only a small portion of the pertinent
• soil and ground-water conditions. The recommendations 'made
herein are based on the assumption that soil conditions do not
deviate appreciably from those found during our field investi-
gation. We recommend that Woodward-Clyde Consultants review
• the foundation and grading plans to verify that the intent of
the recommendations presented herein has been properly
interpreted and incorporated into the contract documents. We
further recommend that Woodward-Clyde Consultants observe the
• site grading, subgrade preparation under concrete slabs and
paved areas, and foundation excavations. If the plans for site
development are changed, or if variations or undesirable
geotechnical conditions are encountered during construction,
•
. the geotechnical consultant should be consulted for further
recommendations. . .
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Project No. 53147K-SIO1
. . . Woodward.CydeConsuftants
This report is intended for design purposes only and may
not be sufficient to prepare an accurate bid. California,
including San Diego, is an area of high seismic risk. It is
generally considered economically unfeasible to build a totally
earthquake-resistant project; it is therefore possible that a
large or nearby earthquake could cause damage at the site.
Gebtechnical engineering and the geologic sciences are
characterized by uncertainty. Professional judgments presented
herein, are based partly on our evaluations of the technical
information gathered, partly on our understanding of the
• proposed construction, and partly on our general experience.
Our engineering work and •judgments rendered meet current
• professional standards; we do not guarantee the performance of
the project in any respect..
Inspection services allow the testing of only a very small
percentage of the fill placed at the site. Contractual
• arrangements with the grading contractor should contain the
provision that he is responsible for excavating, placing, and
compacting fill in accordance with the project specifications.
Inspection by the geotechnical engineer during grading should
• not relieve the grading contractor of his primary
responsibility to perform all work in accordance with the
specifications.
This firm does 'not practice or consult in the field of
. safety engineering. We do not direct the contractor's
operations, and we cannot be responsible for the safety of
personnel other than our own on the site; the safety of others
is the responsibility of the contractor. The contractor should
• notify the owner if he considers any of the recommended actions
presented herein to be unsafe.
•
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fl APPENDIX A S
FIELD INVESTIGATION
S Eight exploratory test borings were advanced at the
approximate locations shown on the Site Plan (Figure 1). The
drilling was performed on April 5 and 6, 1983 using a 6-inch
diameter, continuous-flight power auger. In addition, we made a
visual inspection of the existing bluffs to help evaluate the
erosion potential of the near surface soils.
Samples of the subsurface materials were obtained from the . borings using a modified California drive sampler (2-inch
inside diameter and 2½-inch outside diameter) with thin brass
liners. The sampler was generally driven 18 inches into the
material at the bottom of the hole by a 140-pound hammer
falling 30 inches; thin metal liner tubes containing the sample
were removed from the sampler, sealed to preserve the natural
moisture content of the sample, and returned to the laboratory
for examination and testing.
The location of each boring and the elevation of the S .
ground surface at each location were estimated from the grading
plans provided to us.
S
S
Location Boring Number Elevation
DEPTH
IN
TEST DATA iOTHERI SAMPLE SO I L D ES C R I PT I ON -MC . . FEET TESTS NUMBER
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12 110 65 1
2
S
Very dense, damp, brown silty sand (SM)
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WATER LEVEL
At time of drilling or as indicated.
SOIL CLASSIFICATION
Soil Classifications are based on the Unified Soil Classification System
and include color, moisture and consistency. Field descriptions have
been modified to reflect results of laboratory analyses wtsere
appropriate.
DISTURBED SAMPLE LOCATION
Obtained by collecting the auger cuttings in a plastic or cloth bag.
DRIVE SAMPLE LOCATION
MODIFIED CALIFORNIA SAMPLER
Sample with recorded blows per foot was obtained with a Modified
California drive sampler (2" inside diameter, 2.5" outside diameter)
lined with sample tubes. The sampler was driven into the soil at the
bottom of the hole with a 140 pound hammer falling 30 inches.
INDICATES SAMPLE TESTED FOR OTHER PROPERTIES
GS - Grain Size Distribution CT - Consolidation Test
LC - Laboratory Compaction UCS —Unconfined Compression Test
Test SDS - Slow Direct Shear Test
P1 - Atterberg Limits Test DS - Direct Shear Test
ST - Loaded Swell Test TX— Triaxial Compression Test
CC— Confined Compression R'- R-Value
Test
NOTE: In this column the results of these tests may be recorded
where applicable.
BLOW COUNT
Number of blows needed to advance sampler one foot or as indicated.
DRY DENSITY
Pounds per Cubic Foot
MOISTURE CONTENT
Percent of Dry Weight
NOTES ON FIELD INVESTIGATION
I. REFUSAL indicates the inability to extend excavation, practically,
with equipment being used in the Investigation.
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[KEY TO LOGS
BATIQUITOS POINTE
[DRAWN BY: rákc I CHECKED BY: PROJECT NO: 53147KS101 j DATE: 4-13-83 FIGURE NO: A—i
40 W000WARD-CLYDE CONSULTANTS
Boring 1
Approximate El. 50'
DEPTH
I IN
TEST DATA 'OTHER SAMPLE Sol L D ESC RI PT ION *MC DD BC FEET TESTS UMBER
6 107 11 1-1
fi Medium dense, damp, brown silty medium
1-3 - to fine sand (SM) slightly, porous
- 8 116 37 1-2 Lj TOPSOIL
[ Dense, damp, light brown to brown clayey
5- to silty medium to fine sand (SM)
174 LINDAVISTA FORMATION
44 1-5
lo -
• Very dense, moist, olive brown silty fine,
sand (SM-SP) LINDAVISTA FORMATION 72
'
1-6
V 15
Very dense, saturated, light gray medium
1-7
f
sand (SM) - SANTIAGO FORMATION
Bottom of Hole
20
25-
30-
-
35-
40 -
For description of symbols, see Figure A—i
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LOG OF.TEST BORING 1 '
BATIQUITOS POINTE
DRAWN BY: mkC CHECKED BY: PROJECT NO: 53147K-SIO1 I DATE: 4-13-83 FIGURE NO: A-2
WOODWARD•CLYDE CONSULTANTS
6
8
5-..
7
10
30
7
110 38 GS
40
r 20-
13
25 -
S 30
35..
40- S
L20/
8"
L25/
7"
111 I
L10/
7,,
L48/
6"
Is, see F f symbc igure A
"OTHER' SAMPLE
I.
-______________________________________________________
FEET L MC "DD •BC. TESTS 1NUMBER
SOIL DESCRIPTION
Boring 2
Approximate El. 48'
2-1 . Medium dense to dense, damp, brown silty
2-2 medium to fine sand (SM) with trace of clay
2-3 and slightly porous
2-4 TOPSOIL
Medium dense to dense, light brown silty
to clayey medium to fine sand (SM-SC)
porous LINDAVISTA FORMATION
2-5
Dense, damp, light brown silty medium to
fine sand (SM-SP)
T,TNfl\1TTA FCRMAPTCTh1 2-6
I DEPTH IN TEST DATA
15
L20/
9"
LOG OF TEST BORING 2
BATIQUITOS POINTE
DRAWN BY: mkc I CHECKED BY: PROJECT NO: 53147K—SIO1 DATE: 4-13-83 FIGURE NO: A-3
W000WARD-CLYDE 'CONSULTANTS
45
70
75
80
*For description of symbols, see Figure A—i
LM
50
55
60
65
Boring 2 (Continued).
I DEPTHI IN
FEET
TEST DATA -OTHER (
TESTS NUMBER
SAMPLE
i
SOIL DESCRIPTION MC j DD BC
S
LOG OF TEST BORING 2 (CONTINUED)
BATIQUITOS POINTE
DRAWN BY: mkc I CHECKED BY: PROJECT NO: 53147K—SIO1 I DATE: 4-13-83 1 FIGURE NO: A-4
WOODWARD•CLYDE CONSULTANTS
108 14
5 r
S
S
20
25
30
35
40—i
I,
For description c I symbc
10 -
13
15
109
42
90
120
9
137
9
149
—9
Is, see Figure A—i
DEPTH
IN TEST DATA OTHER
I
SAMPLE SOIL DESCRIPTION MC 'DD (.BC FEET TESTS
LOG OF TEST BORING 3
BATIQIJITOS POINTE
DRAWNBY: mkc I CHECKEDBY: PROJECTNO 53147K—SIO1 DATE: 4-13-83, J FuGuRENo:As
WOODWARD-CLYDE CONSULTANTS
Boring 4
Approximate El. 55'
'DEPTH
IN TEST DATA i'OTHERISAMpLE I SOIL DESCRIPTION T1;- FEET TESTS
•
12 4-1
f Loose to medium dense, damp, brown silty
fine sand (SM) TOPSOIL
12 109 12 4-2
5 Dense, damp, light brown to light red
brown silty to clayey medium to fine
sand (SM-SC) LINDAVISTA FORMATION
9 113 47 GS 4-3
•
Dense to very dense, damp to moist, light
76 4-4 olive gray brown silty medium to fine sand
(SM-SP) LINDAVISTA FORMATION
15
6 107 108 GS 4-5
20- Very dense, saturated, light gray silty
medium to fine sand (SM)
110/ 4-6 SANTIAGO FORMATION
6
25
4-7 -..-_!/ 61'
. Bottom of Hole
30
35 -
40 - • For description of symbols, see Figure A-i
LOG OF TEST BORING 4
BATIQUITOS POINTE
DRAWNBY: mkc CHECKEDBY: PROJECTNO: 53147K-SIO1 DATE: 4-13-83 FIGURE NO: A-6
W000WARD.CLYDE CONSULTANTS
Boring 5
Apprpximate El. 40'
DEPTH TEST DATA OTHER SAMPLE SOIL DESCRIPTION FEET MC 'DO 'BC TESTS NUMBER
Loose to medium dense, moist, brown
silty fine sand (SM)
14 5-1 TOPSOIL
5 Medium dense to dense, saturated, light -
red brown silty medium fine sand (SM)
LINDAVISTA FORMATION
30 5-2
10 —
74 5-3
Bottom of Hole
15 -
Boring 6
Approximate El. 49'
DE
IN
PTH TEST DATA OOTHER SAMPLE SOIL , DESCRIPTION FEET *MC 'DO *BC TESTS NUMBER
• Loose to medium dense, damp, brown silty
- medium sand (SM), porous
22 6-1 - TOPSOIL
Medium dense to dense, damp, red brown
1 4- 14 4-.-. ...-_ - --.--1- -- 5 .
•- LLULI L L.L1It I1U i"1) W.LLIL trace
of clay LINDAVISTA FORMATION
8 109 64 6-2
10 - Damp to moist
62 6-3
Bottom of Hole
15 •
For description of symbols, see Figure A1
LOG OF TEST BORINGS 5 AND 6
BATIQUITOS POINTE
DRAWN BY: mkc I CHECKED BY: PROJECT NO: 53147K—slo1 I DATE: 4-13-83 FIGURE NO: A-7
WOODWARO-CLYDE CONSULTANTS
Boring 7
Approximate El. 53'
IDEPTHI
IN .OTHERI SAMPLE SOIL DESCRIPTION MC
TEST DATAd
DD FEET BTESTS NUMBER
5
. . 10
15
20
25
30
35
[IJ
40
For description of symbols, see Figure A-i
LOG OF TEST BORING 7
BATIQUITOS POINTE
DRAWN BY: mkc I CHECKED BY: PROJECT NO: 53147K-5I01 DATE: 4-13-83 FIGURE NO: A-B
WOODWARD.CLYDE CONSULTANTS
Boring 8
Approximate E1.49'
IDEPTH1 IN
TEST DATA OTHER SAMPLE SOIL DESCRIPTION
I
-MC I -DD BC FEET TESTS NUMBER I
8
5 -
9
10 -
15 1
109
Loose to medium dense, damp,. brown silty
fine sand (SM), porous
TOPSOIL
Medium dense to dense, damp, light red
brown silty medium to fine sand (SM) with
trace of-clay LINDAVISTA FORMATION
Dense to very dense, damp, light olive
gray brown silty sand (SM)
LINDAVISTA FORMATION
V
Very dense, damp, light gray silty medium
fine sand (SM-SP) LINDAVISTA FORMATION
r
107 421 18-2
511
105 GS 8-4
20
100/ 8-5
9,' Bottom of Hole
S
25
30
35
40-S'
S
As, see I igure A-i
LOG OF TEST BORING 8
BATIQUITOS POINTE
DRAWN BY: mkc CHECKED BY: PROJECT NO: 53147K-SIO1 DATE: 4-13-83 FIGURE NO: A-9
WOODWARD•CLYDE CONSULTANTS
Woodward-Clyde Consultants
APPENDIX B
LABORATORY TESTS
The materials observed in the test borings were visually
classified and evaluated with respect to strength, swelling,
and compressibility characteristics; dry density; and moisture
content. The classifications were substantiated by performing
grain size analyses on representative samples of the soils.
The strength of the soils was evaluated by considering the
density and moisture content of the samples and the penetration
resistance of the sampler.
The results of tests on drive samples, except for the
grain size analysis are shown with the penetration resistance
of the ampler at the corresponding sample location on the
logs, Figures A-i through A-9. The grain size distribution
curves are shown in Figure B-i.
11
*
*
S
Ll
COBBLES I GRAVEL I SAND
SILT and CLAY Coarse Fine Icoarsel Medium I Fine
Mesh Opening - Ins Sieve Sizes Hydrometer Analysis
10076 3 2 I 4 2 4 4 10 16 20 30 40 60 80 140200
90
80
70
60 Uj
F°
80
90
100 100 50 1000 5.0 1.0 0.1 0.05 0.01 0.005 0,001.
GRAIN SIZE IN MILLIMETERS
SAMPLE CLASSIFICATION AND SYMBOL *LL
2-5 Silty sand (SM) - -
3-5 Silty sand (SM) - -
4-3 Silty sand (SM) - -
4-5 Sand (SP)
- -
8-4 Sand (SP)
- -
'LL - Liquid Limit
- Plasticity Index
I GRAIN SIZE DISTRIBUTION CURVES
BATIQUITOS POINTE
(DRAWN BY: ch I CHECKED BY: PROJECT NO: 53147K—SIO1 DATE: 4-18-83 FIGURE NO: _]
W000WARD-CLYDE CONSULTANTS
S
LM
U
10
20
30
u-i 60
70
20
IC
C
WCC- GS-76
Woodward-Clyde Consultants
APPENDIX C
GUIDE SPECIFICATIONS FOR CONTROLLED FILL
GENERAL
These specifications cover preparation of existing surfaces to
receive fills, the type of soil suitable for use in fills, the
control of compaction, and the methods of testing compacted
fills. It shall be the contractor's responsibility to place,
spread, water and compact the fill in strict accordance with
these specifications. A soil engineer shall be the owner's S representative to observe the construction of fills. Excava-
tion and the placing of fill shall be under the direct observa-
tion of the soil engineer, and he shall give written notice of
conformance with the specifications upon completion of grading. S Deviations from these specifications will be permitted only
upon written authorization from the soil engineer. A soil
investigation has been made for this project; any recommenda-
tions made in the report of the soil investigation or subse-
quent reports shall become an addendum to these specifications.
SCOPE
The placement of controlled fill by the contractor shall in-
clude all clearing and grubbing, removal of existing unsat-
isfactory material, preparation of the areas to be filled,
spreading and compaction of fill in the areas to be filled, and
all other work necessary to complete the grading of the filled
areas.
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S Woodward-Clyde Consultants
III. MATERIALS
Materials for compacted fill shall consist of any material
imported, or excavated from the cut' areas that, in he opinion
of •the soil engineer,, is suitable for use in constructing
fills. The material shall contain no rocks or hard lumps
greater than 24 inches in size and shall contain at least
40% of material smaller than ¼ inch in size. (Materials
greater than 6 inches in size shall be placed by the contrac-
tor so that they are surrounded by compacted fines; no nesting.
of rocks shall be permitted.) No material of a perishable,
spongy, or otherwise improper nature shall be used in fills.
S.
Material placed within 24 inches of rough grade shall be
select material that contains no rocks or hard lumps greater
than 6 inches in size and that swells less than 3% when com-
pacted as hereinafter specified for compacted fill and soaked
under an 'axial pressure of 160 psf.
Representative samples of material to be used for fill
shall be tested in the laboratory by the soil engineer in order
to determine the maximum density, optimum moisture content, and.
classification of the soil. In addition, the soil engineer
shall determine the approximate. bearing value of a recompacted,
S saturated sample by direct shear tests or other tests applic-
able to the particular soils.
. During grading operations, soil types other than those
analyzed in the report of the soil investigation may be en-
countered by the contractor.. The soil engineer shall be con-
suited to determine the suitability of these soils.
S
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WoodwardClyde Consultants
IV. COMPACTED FILLS
1. General
(a) Unless otherwise specified, fill material shall be com-
pacted by the contractor while at a moisture content near
the optimum moisture content and.to a density that is not
less than 90% of the maximum dry density determined in
accordance with ASTM Test .No. D1557-78, or other density
test methods that will obtain equivalent results.
(b) Potentially expansive soils may be used in fills below a
depth of 24 inches and shall be compacted at .a moisture
content greater than the optimum moisture content for the
material.
2. Clearing and Preparing Areas to be Filled
All trees, brush,. grass, and other objectional material
shall be collected, piled, and burned or otherwise dis-
posed of by the contractor so as to leave the areas that
have been cleared with a neat and finished appearance free
from unsightly debris.
All vegetable matter and objectionable material shall be
removed by the contractor from the surface upon which the
fill is to be placed, and any loose or porous soils shall
be removed or compacted to the depth shown on the plans.
The surface shall then be plowed or scarified to a minimum
depth of 6 inches until the surface is free from uneven
features that would tend to prevent uniform compaction by
the equipment to be used.
•
0 C-3
Woodward-Clyde Consultants
(c) Where fills are constructed on hillsides or slopes, the
slope of the original ground on which the fill is to be
placed shall be stepped or keyed by the contractor, as
shown on the figure included in these specifications.
The steps shall extend completely through the soil mantle.
and into the underlying. formational materials.
(d) After the foundation for the fill has been cleared, plowed
or scarified, it shall be disced or bladed by the con-
tractor until it is uniform and free from large clods,
brought to the proper moisture content, and compacted as
• specified for fill. .
3. Placing, Spreading, and Compaction of Fill Material
The fill material shall be placed by the contractor in
layers that, when compacted, shall not exceed 6 inches.
Each layer shall be spread evenly and shall be thoroughly
mixed during the spreading to obtain uniformity of mater-
ial in each layer.
When the moisture content of the fill material is below
that specified by the soil engineer, water shall be added
by the contractor until the moisture content is as speci-
fied.
When the moisture content of the fill material is above
that specified by the soil engineer, the fill material
. shall be aerated by the contractor by blading, mixing, or
other satisfactory methods until the moisture content is
as specified. .
Woodward-Clyde Consultants
(d) After each layer has been placed, mixed, and spread even-
ly, it shall be thoroughly compacted by the contractor to
the specified density. Compaction shall be accomplished
by sheepsfoot rollers, vibratory rollers, multiple-wheel
pneumatic-tired rollers, or other types of acceptable
grading equipment. Equipment shall be of such a design
that it will be able to compact the fill to the specified
density. Compaction shall be continuous over the entire
area, and the equipment shall make sufficient trips so
that the desired density has been obtained throughout the
entire fill.
(e) The surface of. fill slopes shall be compacted and there
shall be no excess loose soil on the slopes.
V. INSPECTION
1. Observation and compaction tests shall be made by the soil
engineer during the filling and compacting operations so that
he can state his opinion that the fill was constructed in
accordance with the specifications.
2. The soil engineer shall make field density tests in accor-
dance with ASTM Test No. D1556-64. Density tests shall be made
in the compacted materials below the surface where the surface
is disturbed. When these tests indicate that the density of
any layer of fill or portion thereof is below the specified
density, the particular layer or portion shall be reworked
until the specified density has been obtained.
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Woodward-Clyde Consultants
VI. PROTECTION OF WORK
During construction the contractor shall properly grade
all excavated surfaces to provide positive drainage and prevent
ponding of water. He shall control surface water 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 and until such time as permanent drain-
age and erosion control features have been installed.
After completion of grading and when the soil engineer has
finished his observation of the work, no further excavation or
filling shall be done except under the observation of the soil
engineer.
C-6