HomeMy WebLinkAbout3618; PARKING CARLSBAD BLVD AT PONTO BEACH; PRELIMINARY GEOTECHNICAL INVESTIGATION; 1999-04-151 it PETRA
COSTA MESA • SAN DIEGO. TEMECULA • LOS ANGELES
110
RECEIVED
LINTVEDT. McCOLL & ASSOC.
APR 16 1999
April 15, 1999
J.N. 177-99
LINT VEDT, McCOLL & ASSOCIATES
3737 Camino Del Rio South, Suite 200
San Diego, California 92108-4008
Attention: Mr. Kent Madsen
Subject: Preliminary Geotechnical Investigation, Proposed Ponto Beach
Parking, West Carlsbad Boulevard, Carlsbad, California.
Gentlemen:
We are pleased to submit herewith our Preliminary Geotechnical Investigation report
for the proposed Ponto Beach Parking on West Carlsbad Boulevard in Carlsbad,
California. This report presents the results of our field and laboratory investigation,
and conclusions and recommendations concerning the geotechnical design aspects of
the proposed parking area.
LOCATION AND SITE DESCRIPTION
The proposed Ponto Beach parking area is located adjacent to, and west of the south-
bound lane of West Carlsbad Boulevard from approximately station 159+00 to station
170+00. The project site extends basically from the north end of the bridge over the
Batiquitos Lagoon outlet, north to the lifeguard station parking area and is bounded on
the west by a narrow strip of beach and the Pacific Ocean. An asphalt-surfaced area
comprising a traffic run-on lane extends from the lifeguard parking area at the north
end of the site extends approximately 300 feet southerly onto the southbound lane of
West Carlsbad Boulevard. The remainder of the site is presently being used as a
foot/bicycle path. Painted ex-power poles lain on their sides separate the path area
from the traffic and emergency parking lanes.
PEIRA GEOTECHNICAL INC.
12225 World Trade Dr., Ste. 0
San Diego, CA 92128
Tel: (619) 485-5530
Fax: (619)485-8215
LINTVEDT, McCOLL & ASSOCIATES April 15, 1999
J.N. 177-99
Page 2
Topographically, the southern end of the site is at approximately the same elevation
as the adjacent sandy beach area with a gradual increase in elevation towards the north
such that at the northern end of the project there is an approximately twelve-foot high
natural slope from the foot-path elevation to the sandy beach. The sandy beach is
about 100 feet wide and about three to eight feet above mean sea level.
It was observed that fill materials, which contain various asphaltic and portland cement
concrete chunks (construction-type debris), had been end-dumped to extend the width
of the foot/bike path along some portions of the slope that descends to the sandy beach.
Vegetation consisting of grasses, weeds, and bushes, were observed along the edge of
the path and across the slope.
PROPOSED CONSTRUCTION AND GRADING
It is our understanding that development will consist of the construction of an asphaltic
concrete pavement parking lane along the west side of Carlsbad Boulevard in the area
currently occupied by an existing emergency lane and foot/bicycle path. Based on
existing elevations on the site, it is anticipated that only minor grading would be
required to' generate the necessary pavement section. However, depending upon actual
design,,the existing slope may be extended to the west to provide appropriate width.
Recommendations for site grading and for the design of the asphaltic concrete
pavement are presented in the "Conclusions and Recommendations" section of this
report.
FIELD INVESTIGATION
A limited subsurface investigation of the site was conducted on March 19, 1999 by our
personnel consisting of the excavation of 2 hand-dug test pits and the geologic logging
of the natural slope adjacent to hand pit number 1. Logging and selective sampling Of
LINTVEDT, McCOLL & ASSOCIATES April 15,1999.-
J.N. 177-99
Page 3
the test pits were performed by our engineering geologist. Approximate locations of
these hand pits are shown of the attached plot plan, Plate No. 1 in Appendix A.
The exploratory pits were carefully logged when excavated and the logs are presented
in Appendix A. The log of the natural slope is included as test pit number HP-1A.
Soil materials were classified and logged in accordance with the Unified Soil
Classification system. A written textural description, the wet color, the apparent
moisture, and the density or consistency is provided on the log. The density of
granular soils is given as either very loose, loose, medium dense, dense, or very dense.
Disturbed and undisturbed samples of typical and representative soils were obtained
and returned to the, laboratory for testing.
LABORATORY TESTING
In-place moisture content and unit dry density were determined for a sample of soil
material from HP-2. R-Value testing was done on a bulk samples of different material
types from the two hand-pits. Test data are summarized in Appendix B. An evaluation
of the data is reflected throughout the "Conclusions and Recommendations" section
of this report.
FINDINGS
In general the site was found to be underlain by a thin layer of artificial fill material
over bedrock materials consisting of Terrace deposits. The fill material, which
appears to have been placed during the construction of Carlsbad Boulevard, consists
of silty sands, clayey sands, sands and gravely sands which vary in consistency from
loose to dense. Bedrock materials encountered in, the exploratory pits and exposed in
the face of the western slope leading to the beach, consist of silty sandstone and clayey
sandstone deposits which are moderately hard to hard.
ot
LINTVEDT, McCOLL &ASSOCIATES April 15, 1999
J.N. 177-99
Page 4
CONCLUSIONS AND RECOMMENDATIONS
General
From a soils engineering and engineering geologic point of view, the site is considered
suitable for the proposed development provided the following conclusions and
recommendations are incorporated into the design criteria and project specifications.
The major concern when developing the site is the presence, of the artificial fill
material and the potential widening of the area in such a manner as in infringe upon
the beach area. The artificial fill is anticipated to be removed in its entirety during
excavation to the subgrade elevation of the pavement section. However, if existing fill
material exists after this operation, complete removal and recompaction of the soils
will be required.
Grading Plan Review
The following "Earthwork" recommendations are based on a review of the preliminary
site plans prepared by Lintvedt, Mccoll & Associates which were supplied to our
office and on an anticipated grading concept. Therefore, when the finalized grading
plan has been prepared, it should be reviewed by the project geotèchnical consultant
with respect to the geotechnical aspects of the planned site development. Depending
on the results of the grading plan review, revised and/or additional recommendations
should be prepared by the geotechnical consultant as deemed appropriate.
General Earthwork and Grading Specifications
All earthwork and grading should be performed in accordance with the applicable
provisions of the Grading Code of the City of Carlsbad, in accordance with the
following recommendations prepared by this firm, and our Standard Grading
Specifications presented in Appendix C.
LINT VEDT, McCOLL & ASSOCIATES April 15,1999
J.N. 177-99
Page 5
Site Preparation
All weeds, grasses, brush, shrubs, and similar vegetation, trash and construction-type
debris should be stripped and removed from the site in those areas to be graded, prior
to any grading. Remaining roots from vegetation exposed during grading may require
hand labor for proper removal.
Grading should begin with the complete removal of the existing artificial fill material
below the proposed subgrade elevations and the replacement of the soils as uniformly
compacted fill material at slight above optimum moisture contents. In areas to receive
fill after removal of existing fill and cuts of less that one foot, the near-surface soils
should be scarified to a depth of approximately twelve inches, moisture conditioned
to near-optimum moisture contents by addition of water Or drying back, and
recompacting the soils to at least 90 percent of their maximum dry densities. If
pockets of loose, dry weathered bedrock materials are encountered which extend to
depths in excess of twelve inches,,the material should be removed in its entirety and
replaced as properly compacted fill material.
Geotechnical Observations
Exposed bottom surfaces in any removal area should be observed and approved by the
project geotechnical consultant ,prior to placing any fill to achieve proposed subgrade
elevation. No fills should be placed without prior approval from the geotechnical
consultant
The project geotechnical consultant should also be present on-site during grading
operations to verify proper placement and adequate compaction of fill, as well as to
verify compliance with the other recommendations presented herein.
I
LINTVEDT, McCOLL & ASSOCIATES April 15, 1999
J.N. 177-99
Page-6
I
Excavation Characteristics
The on-site excavated materials are anticipated to consists of fill and bedrock material
I of various compositions of silty sands, clayey sands, sands and gravelly sands. It is
anticipated that the on-site soils will be relatively easy to excavate with normal
I construction equipment..
I Ground Preparation Fill Areas
Existing loose surficial soils or existing artificial fill in areas to receive fill material
I should be removed to underlying natural ground materials. Exposed surfaces of the
removals or areas of asphaltic concrete pavement removal which expose natural
I ground materials, should be scarified to a depth of approximately six inches, watered
or air dried as necessary to achieve near optimum moisture conditions, and then
I recompacted in to 90 place a minimum relative compaction of percent.
I Fill Placement - _Conventional
I On-site excavated materials, maybe used as compacted material or backfill. All fill
should be placed in lifts not exceeding eight inches in thickness, watered as necessary
I to, achieve near-optimum moisture conditions, and then compacted in-place to a
minimum relative compaction. of 90 percent. Each fill lift should be treated in a
I similar manner. Subsequent hfts should not be placed until the preceding lift has been
approved by the project geotechnical consultant
The laboratory maximum dry density and optimum moisture content for each change
I in soil type should be determined in accordance with Test Method ASTM D 1557-91.
I
I
I.
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LINT VEDT, McCOLL & ASSOCIATES April 15, 1999
J.N. 177-99
S Page
I
Fill Slope Constructiàfl
Fill keys having a minimum width of 15 feet or 1.5 times the width of the excavation
I and compaction equipment should be provided at the base of all fill slopes. The fill
keys should extend through the loose surficial soils and excavated at least 2 feet into
dense, competent ancient alluvium or bedrock, and tilted slightly into slope.
I The finish surfaces of all fill slopes should be compacted to a minimum relative
density of 90 percent. This surface compaction should be achieved by overfilling the
I slopes during construction, backrolling to overfilled slope surfaces at vertical intervals
not exceeding 3 to 4 feet, and then trimming the slopes back to the compacted inner
I core.
I Benching
Compacted fills placed on natural slope surfaces inclining at 5:1 or greater (horizontal
I to vertical), should be placed On a series of level benches excavated into competent
native soils or bedrock. Benches should be at least 1.5 times the widths of the
I excavation and compaction equipment, and provided at vertical elevations of 3 to 4
- feet.
I
PRELIMINARY PAVEMENT SECTION RECOMMENDATIONS
Based on an assigned traffic index of.8.5 for a major arterial by the City of Carlsbad,
I . and the Resistance Value (R-Value) results, preliminary pavement section
recommendations are presented hereafter.
5.0 Inches of Asphaltic Concrete Pavement
on. 6.0 Inches of Class II aggregate base
on 12.0 Inches of compacted subgrade
I
LD1TVEDT, McCOLL & ASSOCIATES April 15, 1999
J.N. 177-99
Page 8
Subgrade soils shoàld be properly compacted, smooth, and non-yielding prior to
pavement construction. The subgradc soils should be compacted to at least 95 percent
of ASTM D1557-91. Any areas of sift or spongy soils should be removed and
replaced with compacted fill.
Class H aggregate base materials should conform to Section 200-2 of the Standard
Specifications for Public Works Construction (Greenbook), or California Standard
Specifications. The materials should be brought to a near optimum moisture then
compacted to at least 95 percent of ASTM D1557-91. Asphaltic concrete materials
and construction should conform to Section 203 of the "Greenbook".
Near the completion of grading, soils being used at or within the upper three feet of the
proposed subgrade elevation, should be reviewed to determine if additional R-value
testing may be appropriate.
INVESTIGATION LIMITATIONS
This report is based on the proposed project and geotechnical data as described herein.
The materials encountered on the project site, described in other literature, and utilized
in our laboratory investigation are believed representative of the total project area,. and
the conclusions and recommendations contained in this report are presented on that
basis. However, soils can vary in characteristics between points of exploration, both
laterally and vertically, and those variations could effect the conclusions and
recommendations contained herein. As such, observation and testing by a geotechnical
consultant during the construction phase of the project are essential to confirming the
basis of this report. To provide the greatest degree of continuity between the design
and construction phases, consideration should be given to retaining Petra Geotechnical,
Inc. for construction services.
LINTVEDT, McCOLL & ASSOCIATES S April 15, 1999
J.N. 177799
Page
This report has been prepared consistent with that level of care being provided by other
professionals providing similar services at the same locale and in the same time period.
The contents of this report are professional Opinions and as such, are not to be
considered a guaranty or warranty.
This report should be reviewed and updated after a period of one year or project
concept changes from that described herein.
Respectfully submitted, S
PETRA GEOTECHNlCAIG: (4 k.
S.
042204
Ronald SHalbert xp Mar. ii000 j)2)Roy J. Rushing' OF c t
Senior Associate En ]p Senior Associate Geologist
R.C.E. 42204 or CA R.E.G 1.080
Distribution: (5) Submitted
cc: c:\myfiles\I999\100\177-99.pgeoinv
t
Run-On Traffic j
Approximate Stations CD
LO
Southbound Travel Lane
CU North Carlsbad Blvd.
CD
-joot/bicyle Path Cr HP-1 HP-2
Emergency Parking Lane!
CU
DRAWING NOT TO SCALE
TEST PIT LOG
Project: Ponto Beach Parking Test Pit No.: HP-1
Location: Carlsbad Blvd. at Ave. Encinas Elevation: 24
Job No.: 177-99 Client: Lintvedt, McColl &Assoc. Date: 3/19/99
Method: Hand Dug Driving Weight: Logged By: RJR
Depth
(Feet)
Lith-
ology
Material Description a
e r
Samples
-
Laboratory Tests
Blows
Per
Foot
C
0
e
B
k
u Content
Moisture
(%)
Dry
Density
(pcf)
Other
Lab
Tests
FTh.E ELL
Silty Sand (SM): Dark brown; dry to slightly moist; medium
• dense to dense; 1-2" layer of sand and gravel on surface;
:...:
trash and debris (glass, plastic bag, paper; occasional cobbles
toO.65ft. - -
@0.65 Feet:Moderate brown; dry; medium dense.
Sand (SP): Gray; dry to slightly moist; loose to medium : R :
dense with depth. -
RIDROK Silty Sandstone (SM): Light to reddish brown;
dry; hard.
Total Depth = 1.8 Feet
Slight Caving from 1.1 to 1.4 Feet
No Ground Water
PLATE A-i
Petra Geotechnical, Inc.
TEST PIT LOG
Project: Ponto Beach Parking Test Pit No.: BF-1A
Location: Carlsbad Blvd. at Ave. Encinas Elevation:
Job No.: 177-99 Client: Lintvedt, McColl & Assoc. Date: 3/19/99
Method: Exposed Slope Driving Weight: Logged By: RJR
Depth
(Feet)
Lith-
ology
Material Description a
t
r
Samples
-
Laboratory Tests
Blows
Per
Foot
C
e
B
k
Moisture
Content
(%)
Dry
Density
(pct)
Other
Lab
Tests
2
__, ---.-'--,
I-,
- 7 -
—8—:-''--
-9.--
H
FILL
See descriptions in HP-1
--
BEDROCK
Silty Sandctone See description mflP4
Clayey Sandstone: White to light grey; dry; moderately
hard.
Silty Sandstone: Moderate brown; dry, moderately hard to
hard; with gravel and cobbles.
.
-
* -
--
- -
* -
* --
--
--
Continued Next Page PLATE A-2
Petra Geotechnical, Inc.
it
TEST PIT LOG
Project: Ponto Beach Parking Test Pit No.: HP-1A
Location: Carlsbad Blvd. at Ave. Enemas Elevation:
Job No.: 177-99 Client: Lintvedt, McColl & Assoc. Date: 3/19/99
Method: . Exposed Slope Driving Weight: Logged By: RJR
Samples
-
Laboratory Tests
Blows C B Moisture Dry Other Material Description a
Depth Lith- Per Content Density Lab
(Feet) ology r Foot e k (%) (pct) Tests
Silty Sandstone (cont.)
_11_.-•'-:-- ii
12
Exposed Slope Height = 12+/-Feet
PLATE A-3
Pétra Geótechnical, Inc.
-
TEST PIT LOG
Project: Ponto Beach Parking - Test Pit No.: HP-2
Location: Carlsbad Blvd. at Ave. Encinas Elevation: 16
Job No.: 177-99 Client: Lintvedt, McColl & Assoc. Date: 3/19/99
Method: Hand Dug
-
Driving Weight: Logged By: RJR
Samples
-
Laboratory Tests
Blows C B Moisture Dry Other Material Description a
Depth Lith e Per 0 u Content Density Lab
(Feet) ology r Foot e k (%) (pcf) Tests
FIIJ
:JJ4 Silty Sand (SM/SP): Light Brown to gray; dry; loose.
@0.2 Feet: Dark brown; slightly moist; dense. -.
Asphaltic Concrete: Dark brown to black; dense; petroleum 1 - 9.2 125.1 aroma.
Clayey slightly moist; medium
dense; trace to some gravel. :::: R
Asphaltic Concrete- Dark brown to black; dense; petroleum
- 2 - aroma.
Silty Sand (SM): Dark reddish brown; moist; medium dense
to dense.
NATURAL GROUND
Gravelly Sand (SP/GP): Light to moderate brown; slightly
moist; loose to medium dense.
Total Depth = 2.3 Feet
Slight Caving from 1.4 Feet
No Ground Water
PLATE A-4
Petra Geotechnical, Inc.
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LINTVEDT, McCOLL & ASSOCIATES April 15, 1999
J.N. 177-99
STANDARD GRADING SPECIFICATIONS
These specifications present the usual and minimum requirements for projects on
which Petra Geotechnical; Inc. is the geotechnical. consultant
No deviation from these specifications will be allowed, except where specifically
superseded in the preliminary geology and soils report, or in other written
communication signed by the Soils Engineer or Engineering Geologist of record.
I. GENERAL
A. The Soils Engineer and Engineering Geologist are the Owner's or
Builders' representative on the Project. For the purpose of these
specifications, participation by the Soils Engineer includes that
observation performed by any person or persons employed by, and
responsible to, the licensed Civil Engineer signing the soils report.
B.. Alf clearing, site preparation, or earthwork performed on the
project shall be conducted by the Contractor under the supervision
of the Soils Engineer.
C. It is the Contractor's responsibility to prepare the ground surface
to receive the fills to the satisfaction of the Soils Engineer and to
place, spread, mix, water, and compact the fill in accordance with
the specifications of the Soils Engineer. The Contractor shall also
LINTVEDT, McCOLL& ASSOCIATES April 15, 1999
J.N. 17799
remove all material considered unsatisfactory by the Soils
Engineer.
It is also the Contractor's responsibility to have suitable and
sufficient compaction equipment on the job site to handle the
amount of fill being placed. If necessary, excavation equipment
will be shut down to permit completion of compaction. Sufficient
watering apparatus will' also be provided by the Conttactor, with
due consideration for the fill material, rate of placement, and time
of year.
A final report shall be issued by the Soils Engineer and
Engineering Geologist attesting to the Contractor's conformance
with these specifications.
II. SITE PREPARATION
A All vegetation and deletenous material shall be disposed of off
site This removal shall be concluded prior to placmg fill
B. Soil, alluvium, or bedrock materials determined by the Soils
Engineer as being unsuitable for placement in compacted fills
shall be removed from the site Any material incorporated as a part
of a compacted fillmustbe approved by the Soils Engineer.
C. After the ground surface to receive fill has been cleared, it shall be
scarified, disced, or bladed by the Contractor until it is uniform
and free from ruts, hollows, hummocks, or other uneven features
LINTVEDT, McCOLL & ASSOCIATES April 15, 1999
J.N. 177-99
which may prevent uniform compaction.
The scarified ground surface shall then be brought to optimum
moisture, mixed as required, and compacted as specified.' If the
scarified zone is. greater than 12 inches in depth, the excess shall
be removed and placed in lifts restricted to 6 inches.
'Prior to placing fill, the ground surface to receive fill shall be
inspected, tested, and approved by the Soils Engineer.
D. Any underground structures such as cesspools, cisterns,, mining
shafts, tunnels, septic tanks, wells, pipe lines, or others are to be
removed or treated in a manner prescribed by the Soils Engineer.
E In order to provide umform bearing conditions in cut-fill transition
lots and where cut lots are partially in soil, colluvium, or
unweathered bedrock materials, the bedrock portion of the lot
extending a minimum of 3 feet outside of building lines shall be
over excavated a minimum of 3 feet and replaced with compacted
fill. (Typical details are given on Plates SG-1..)
ilL COMPACTED FILLS
A. Any material imported or excavated on the property may be
utilized in the fill, provided each material has been determined to
be suitable by the Soils Engineer. Roots, tree branches, and other
matter missed during clearing shall be removed from the fill as
directed by the Soils Engineer.
LINTVEDT, McCOLL & ASSOCIATES April 15, 1999
J.N. 177-99
B. Rock fragments less than 6 inches in diameter may be utilized in
the fill; provided:
1.' They are not placed in concentrated pockets.
There is a sufficient percentage of fine grained material to
surround the rocks.
The distribution of rocks is supervised by the Soils Engineer.
C. Rocks greater than 6 inches in diameter shall be taken off site, or
placed in accordance with the recommendations of the Soils
Engmeer in areas designated as suitable for rock disposal (A
typical detail for Rock Disposal is given in Plate SG-2)
D Material that is spongy, subject to decay, or otherwise considered
unsuitable shall not be used in the compacted fill
Representative samples of material to be utilized as compacted fill
shall be analyzed by the laboratory of the Soils Engineer to
determine their physical properties. If any material other than that
previously tested is encountered during grading, ,the appropriate
analysis of this material shall be conducted by the Soils Engineer
as soon as possible.
Material used in the compaction process shailbe evenly spread,
t
LINTVEDT, McCOLL & ASSOCIATES April 15, 1999
T'T l'•V? (C
watered processed, processed, and compacted in thin lifts not to exceed 6
inches in thickness to obtain a uniformly dense layer The fill shall
be placed and compacted on a.horizontal plane, unless otherwise
approved by the Soils Engineer.
G. If the moisture content or relative density varies from that required
by the Soils Engineer, the Contractor shall rework the fill until it
is approved by the Soils Engineer.
H Each layer shall be compacted to 90 percent of the maximum
density m compliance with the testing method specified by the
controlling governmental agency. (In general, AS1'M D-1557-91,
the five-layer method will be used.)
If compaction to a lesser perôentage is authorized by the
controlling governmental agency because of a specific land use or
expansive soils condition, the area to receive fill compacted to less
than 90 percent shall either be delineated on the grading plan or
appropriate reference, made to the area in the soils report.
All fills, shall be keyed and benched through all topsoil, colluvium,
alluvium or creep material, into sound bedrock or firm material
except where the slope receiving fill. exceeds a ratio of five
horizontal to one ', vertical, in accordance with the
recommendations of the Soils Engineer.
J. The key for hillside fills should be a minimum of 15 feet in width
and within bedrock or firm 'materials, unless otherwise specified
It
LINTVEDT, McCOLL & ASSOCIATES April 15, 1999
J.N. 177-99
in the soils report. (See detail on Plate SG-3).
Subdrainage devices shall be constructed in compliance with the
ordinances of the controlling governmental agency, or with the
recommendations of the Soils Engineer or Engineering Geologist.
(Typical Canyon Subdrain details are given in Plate SG-4.)
The contractor will be required to obtain a minimum relative
compaction of 90 percent out to the finish slope face of fill slopes,
buttresses, and stabilization fills. This may be achieved by either
overbuilding the slope and cutting back to the compacted core, or
by direct compaction of the slope face with suitable equipment, or
by any other procedure which produces the required compaction.
All fill slopes should be planted or protected from erosion by other
methods specified in the soils report.
Fill-over-cut slopes shall be properly keyed through topsoil,
colluvium or creep material into rock or firm materials, and the
transition shall be stripped of all soil prior to placing fill. (See
detail on Plate SG-7.)
IV. CUT SLOPES
The Engineering Geologist shall inspect all cut slopes at vertical
intervals not exceeding 10 feet.
If any conditions not anticipated in the preliminary report such as
ato
P
I LINTVEDT, McCOLL& ASSOCIATES April 15, 1999
J.N. 177-99
I S perched water, seepage, .lenticular or confined strata of a
I
. potentially adverse nature, unfavorably inclined bedding, joints or
fault planes are encountered during grading, these conditions shall
I be analyzed by the Engineering Geologist and Soils Engineer, and
recommendations shall be made totreat these problems. (Typical
details for stabilization of a portion of a cut slopes are given in
Plates SG-5 and SG-8).
I. . .
Cut slopes that face in the same direction as the prevailing
I . . drainage shall be protected from. slope wash by a nonerodible
interceptor swale placed at the top of the slope:
I
. Unless otherwise specified in the soils and geological report, no
cut slopes shall be excavated higher or steeperthan that allowed.
by the ordinances of controlling governmental agencies.
I
. E. Drainage terraces shall be constructed in compliance with the
ordinances of controlling governmental agencies, or with the
I . . .
. recommendations of the Soils Engineer orEngineering Geologist.
I V. GRADING CONTROL
I A Observation of the fill placement shall be provided by the Soils
Engineer during the progress of grading.
I .
B. In general, density tests should be made at intervals not exceeding
I . S • • 2 feet of fill height or every 500 cubic yards of fill placement. This
I .
S criteria will vary depending on soil conditions and the size of the
LINTVEDT, McCOLL'& ASSOCIATES April 15, 1999
J.N. 177-99
job. In any event, an adequate number of field density tests shall
be made to verily that.the required compaction is being achieved.
C. Density tests should also be made on the surface material to
receive fill as required by the Soils Engineer.
D. All cleanouts, processed ground to receive fill, key excavations,
subdrains, and rock disposals must be inspected and approved by
the Soils Engineer or Engineering Geologist prior to placing any
fill. It shall be the Contractor's responsibility to notify the Soils
Engineer when such areas are ready for inspection.
VI. CONSTRUCTION CONSIDERATIONS
Erosion control measures, when necessary, shall be provided by
the Contractor during grading and prior to the completion and
construction of permanent drainage controls.
Upon completion of grading and termination of inspections by the
Soils Engineer, no further filling or excavating, including that
necessary for footings, foundations, large tree wells, retaining
walls, or other features shall be performed without the approval of
the Soils Engineer or Engineering. Geologist.
Care shall be taken by the Contractor during final grading to
preserve any berms, drainage terraces, interceptor swales, or other
devices of permanent nature on or adjacent to the property.
CUT LOT
UNSUITABLE MATERIAL EXPOSED IN PORTION OF CUT PAD
A LE EDR0 CK
- - -
0pSOlLs COLLUVI
5' -..uu--- -- PROPOSED GRADE I
COMPACTED
APPR
COMPETENT
OVED
BEDROCK
TYPICAL BENCHING
ORIGINAL GRADE
- - -
-
(D)
OR
I 5' MIN.
(D)
OVEREXCAVATE
AND RECOMPACT
DEPTH OF FILL (F) DEPTH OF OVEREXCAVATION (D)
FOOTING DEPTH TO 3 FEET EQUAL DEPTH
3TO6FEET 3FEET
GREATER THAN 6 FEET ONE—HALF THE THICKNESS OF FILL PLACED ON THE
'FILL' PORTION (F) TO 15 FEET MAXIMUM.
CUT-FILL TRANSITION LOT
ORIGINAL
\G ROUND
-
-
—
(D)
OR
5'I N - ---
PROPOSED GRAD.
-_- ()
130- \1 COMPACTED (F)
COMPETENT BEDROCK OR
FILL
APPROVED FOUNDATION MATERIAL OVEREXCAVATE
AND RECOMPACT
---I
TYPICAL BENCHING
PONTO BEACH PARKING
PETRA GELITECHNICAL I INC,DWG. BY: RSH DATE: 04-15-99
JOB NO.: 177-99 PLATE SG-1
TYPICAL ROCK DISPOSAL DETAIL
FINISHED GRADE
CLEAR AREA FOR FOUNDATIONS, 4 13' / SLOPE FACE UTILITIES, AND SWIMMING POOLS -I-
15'--._, Y STREET
15' 5' OR BELOW DEPTH
OF DEEPEST UTILITY TRENCH,
'- WINDROW WHICHEVER IS GREATER.
TYPICAL WINDROW DETAIL (END VIEW)
HORIZONTAL PLACED
COMPACTED FILL
6 TO 8 INCH LIFTS
GRANDULAR SOIL FLOODED
TO FILL VOIDS
PROFILE VIEW
PONTO BEACH PARKING
PETRA GELITECHNICAL ) INC, DWG, BY: RSH DATE: 04-15-99
JOB NO.177-99 PLATE SG-2
FILL SLOPE ABOVE NATURAL SLOPE
FINISHED GRADE
TOE OF SLOPE AS SHOWN COMPACTED FILL
ON GRADING PLANS
NATURAL
TOPOGRAPHY 7
-
-
TYPICAL BENCHING /•/
COMPETENT BEDROCK OR APPROVED
PROJECTION FOUNDATION MATERIAL
2% MIN.
H 15' MINIMUM - I
BASE KEY WIDTH I
2' MIN. DOVNSLDPE
KEY DEPTH
NOTE: WHERE NATURAL SLOPE GRADIENT IS 5:1 OR LESS, BENCHING IS NOT NECESSARY
HOWEVER, FILL IS NOT TO BE PLACED ON COMPRESSIBLE OR UNSUITABLE MATERIAL.
PONTO BEACH PARKING
PETRA GEUTECHNICAL, INC,DG, BY RSH IDATE: 04-15-99
JOB NO.: 177-99 PLATE SG-3
CANYON SUBDRAIN DETAIL
- NATURAL GROUND
TYPICAL
BENCHING
COMPETENT BEDROCK OR
SEE DETAIL BELOW APPROVED FOUNDATION
NOTE: FINAL 20 FEET OF PIPE AT OUTLET
SHALL BE NON-PERFORATED
FILTER MATERIAL- MINIMUM OF 9
CUBIC FEET PER LNEAL FOOT.
4 SEE PLATE SG-6 FOR FILTER
MATERIAL SPECIFICATIONS.
4 4
4
4 44 4
CHARACTERISTICS 4 ALTERNATE IN LIEU OF
FILTER MATERIAL
44
9 CUBIC FEET PER LINEAL FOOT OF
4 . OPEN-GRADED GRAVEL ENCASED IN
44 FILTER FABRIC. SEE PLATE SG-6 FOR
GRAVEL SPECIFICATIONS.
FILTER FABRIC SHALL BE MIRAFI
140N OR APPROVED EQUAL.
MINIMUM 6-INCH DIAMETER PVC SCHEDULE 40 OR ABS
SCR-35 WITH A MINIMUM OF 16 PERFORATIONS PER
LINEAL FOOT IN BOTTOM HALF OF PIPE. PIPE TO BE LAID
WITH PERFORATIONS DOWN.
FOR CONTINUOUS RUNS IN EXCESS OF 500 FEET
USE 8-INCH DIAMETER PIPE.
PDNTD BEACH PARKING
tPETRA GEUTECHNICALI INC DWG. BY: RSH DATE: 04-15-99
JIB NO.: 177-99 PLATE' SG-4
DEPTH AND BEDDING MAY
VARY WITH PIPE AND LOAD
BUTTRESS DR STABILIZATION FILL DETAIL
TO TOP OF BACK CUT
15' MIN.
FINISHED GRADE
4' SUBDRAIN
FINISHED
BDRA 30' MAXIMUM SPACING SEE DETAIL
PLATE SG-6
_,'~<4' ~SU
GRADE
IN
2'M IN. 2 MIN. // -TYPICAL BENCHING
WIDTH VARIES (15' MIN.)
NOTES:
1. MAXIMUM VERTICAL SPACING OF PERFORATED PIPE OF 30 FEET.
2, MAXIMUM HORIZONTAL DISTANCE BETWEEN NON-PERFORATED
PIPE OF 100 FEET.
3. MINIMUM GRADIENT OF TWO PERCENT OF ALL PERFORATED PIPE AND
NON-PERFORATED OUTLET PIPE.
100' MAX.
MIN
OUTLET PIPE (TYPICAL) PERFORATED PIPE (TYPICAL)
PDNTD BEACH PARKING
PETRA GELITECHNICAL I INC DJG, BY: RSH DATE 04-15-99
JOB NO.: 177-99 PLATE SG-5
12
!1.112' MIN "u
BUTTRESS DR STABILZATIDN FILL SUBDRAIN
SLOPE FACE
A
/
- 27 MIN,
APPROVED FILTER MATERIAL.
5 CUBIC FEET PER LINEAL FOOT.
WITHOUT FILTER FABRIC, 3 CUBIC
FEET WITH FABRIC
4-INCH PERFORATED PIPE WITH
PERFORATIONS DOWN. MINIMUM
2% GRADE TO OUTLET PIPE.
4-INCH NON-PERFORATED PIPE.
MINIMUM 2% GRADE TO OUTLET.
APPROVED ON SITE MATERIAL PER SOILS ENGINEER
COMPACTED TO A MINIMUM OF 90% MAXIMUM DENSITY.
4-INCH NON-PERFORATED PIPE
SECTION A-A
PIPE SPECIFICATIONS
4-INCH MINIMUM DIAMETER, PVC SCHEDULE 40, OR ABS SDR-35.
MINIMUM 16 PERFORATIONS PER FOOT ON BOTTOM ONE-THIRD OF PIPE.
FILTER MATERIAL SPECIFICATIONS
CLASS 2 PERMEABLE FILTER MATERIAL PER CALTRANS STANDARD SPECIFICATION 68-1.025
CLASS 2
SIEVE SIZE PERCENT PASSING
1-INCH 100
3/4-INCH 90-100
3/8-INCH 40-100
NO. 4 25-40
NO. 8 18-33
NO. 30 5-15
NO. 50 0-7
NO. 200 0-3
ALTERNATE: OPEN GRADED GRAVEL ENCASED IN FILTER FABRIC. (MIRAFI 140N OR EQUAL)
OPEN -GRADED
SIEVE SIZE PERCENT PASSING
1 1/2-INCH 88-100
1-INCH . 5-40
3/4-INCH 0-17
3/8-INCH 0-7
NO. 200 0-3
PDNTD BEACH PARKING
tPETRA GEIIITECHNICAL, INC. DWG. BY: RSH DATE: 04-15-99
JOB NO.: 177-99 PLATE SG-6
- - - - - - - - - - - - - - - - - - -
FILL SLOPE ABOVE CUT SLOPE
COMPACTED FILL
CUT/FILL CONTACT
- SHOWN ON GRADING PLAN
REMOVE ALL TOPSOIL, COLLUVIUM,
OR CREEP MATERIAL FROM
TRANSITION
AS-BUILT SHOWN ON
NATURAL
TOPOGRAPHY - \ J ....- t-----1 -
TIIJ!I. VARIES 10' TYPICAL
CUT ' 15' MINIMUM -
OR PER SOILS ENGINEER BEDROCK OR APPROVED FOUNDATION MATERIAL
— — — — — — — — — — — - — — — —. — — —
NATURAL
TOPOGRAPHY
STABILIZATION FILL DETAIL
-
JAPI S
-
z_-
2Z MIN
V4' TYPICAL
.0$
ARIES 10' TYPICAL
NISH GRADE
COMPACTED FILL
BEDROCK OR APPROVED FOUNDATION MATERIAL
NOTE: 1. SUBDRAINS NOT REQUIRED UNLESS SPECIFIED.
2. V' SHALL BE EQUIPMENT WIDTH (15') FOR SLOPE HEIGHTS LESS THAN 30 FEET
FOR SLOPE HEIGHTS GREATER THAN 30 FEET, 'W SHALL BE DETERMINED BY
THE PROJECT SOILS ENGINEER
I .'
COMPACTED
FILL I
NO \
INSTALL 6-INCH PIPE SUBDRAIN
PER PLATES SG-4 AND SG-8
SHEAR KEY ON DAYLIGHT CUT LOTS
EXISTING TOPOGRAPHY
PROPOSED DAYLIGHT CUT
PROPOSED CUT LOT RECONSTRUCT AT
1.5:1 OR FLATTER
NOTE: V' SHALL BE 10 FEET DR AS DETERMINED
BY THE PROJECT SOILS ENGINEER
*PETRA GELITECHNICAL I INC PONTO BEACH PARKING
1E225 WORLD TRADE DRIVE, SUITE 0 DWG. BY: RSH DATE: 04-15-99
SAN DIEGO, CALIF. 9128
(619) 485-8502 FAX (619) 485-8215 JOB NO.: 177-99 PLATE SG-9 -