HomeMy WebLinkAboutX2017-3994 - Soils (2)7-3574
COAST GEOTECHNICAL, INC. 203$ ®ceGn Fod Z_
1200 West Commonwealth Ave. Fullerton. CA 92833 • Ph: (714) 870-1211 • Fax: (714) 870-1222 • e-mail: coasteeotec(n sbceloba] net
April 20, 2018 W.O. 532917-05
Ms. Adrienne Armstrong
2038 East Ocean Front
Newport Beach, CA 92663
Subject: Rough Grade Compaction Report for
Proposed New Residence at 2038 East
Ocean Front, Newport Beach, California
References:
1. Geotechnical Engineering Investigation for Proposed New Residence, 2038 East Ocean
Front, Newport Beach, California; by Coast Geotechnical, Inc., W.O. 532917-01, dated
May 31, 2017.
2. Geotechnical Addendum Report for Basement Construction for Proposed New Residence
at 2038 East Ocean Front, Newport Beach, California; by Coast Geotechnical, Inc., W.O.
532917-02, dated August 14, 2017.
3. Geotechnical Opinion Concerning the Proposed Infiltration Design for the 2038 East
Ocean Front, Newport Beach, California; by Coast Geotechnical, Inc., W.O. 532917-03,
dated October 11, 2017.
4. Response to Geotechnical Report Review Comments for 2038 East Ocean Front, Newport
Beach, California; by Coast Geotechnical, Inc., W.O. 532917-04, dated March 2, 2018.
Dear Ms. Armstrong:
Forwarded herewith is the rough grade compaction report for the subject site. Earthwork was
conducted from April 4, 2018 through April 13, 2018, utilizing the referenced geotechnical
reports as a guideline.
PLACEMENT OF FILL
Compacted fill material was placed to provide adequate support for the proposed structure.
The over -excavation of the building pad area extended into competent native material at a depth
of approximately three to three and one half feet below proposed finish grade. The exposed
surface was scarified; moisture conditioned and compacted to a minimum of 90% relative
compaction.
Subsequent fills were placed in six to eight inch loose lifts, moisture conditioned as needed with
a water hose, and compacted to a minimum of 90% relative compaction by track rolling.
Portland Cement was mixed in with the upper two feet of fill to reduce caving during future
foundation excavations. This process was followed to final grade.
COAST GEOTECHNICAL, INC.
Ms. Adrienne Armstrong 2 W.O. 532917-05
Rough Grade Comnaction Report April 20 2018
Limits of grading are shown on the attached Plate 1.
Equipment used for compaction of the fill soils consisted of a SVL 90 Kubota rubber track loader
and a bobcat mini excavator. Earthwork was by Tight Quarters.
TESTING
Maximum density optimum moisture relationship determinations were performed for each soil
type encountered during grading operations. Test results were as follows:
Laboratory Standard: (ASTM:D-1557)
4 -inch diameter mold; 1/30 ft3 volume;
5 layers at 25 blows per layer;
10 lb. hammer dropped 18 inches
Compaction tests were performed a minimum of every two feet and/or 500 cubic yards of
compacted fill soils placed. These tests were performed in accordance with ASTM test methods.
The test results are summarized in Table 1. The approximate test locations are shown on Plate 1.
FOUNDATIONS -
Foundations for the proposed structures may consist of continuous or isolated footings placed a
minimum of 24 inches below lowest adjacent grade and bearing a minimum of 24 inches into
engineered fill. Foundations may utilize an allowable bearing value of 1,800 psf This value is
for dead plus live load and may be increased 1/3 for total including seismic and wind loads
where allowed by code.
Where isolated pads are utilized, they shall be tied with grade beams in both directions to
adjacent foundations.
All footings shall be reinforced with a minimum of four #5 bars, two top and two bottom. The
structural engineer's recommendations for reinforcement shall be utilized where more severe.
Foundation excavations shall be observed by a representative of COAST GEOTECHNICAL, INC.
prior to placement of steel and concrete, to verify compliance with geotechnical recommendations.
COAST GEOTECHNICAL, INC.
Ms. Adrienne Armstrong 3 W.O. 532917-05
Rough Grade Compaction Report April 20 2018
FOUNDATIONS -SECONDARY STRUCTURES
Property line walls, planter walls, and other incidental foundations may utilize conventional
foundation design.
Continuous spread footings or isolated pads placed a minimum depth of 24 inches below lowest
adjacent grade may utilize an allowable bearing value of 1,500 pounds per square foot. This
value is for dead plus live load and may be increased 1/3 for total including seismic and wind
loads where allowed by code.
Where isolated pads are utilized, they shall be tied in two directions into adjacent foundations
with grade beams.
Footing excavations shall be observed by a representative of COAST GEOTECHNICAL, Inc.,
prior to placement of steel or concrete to verify competent soil conditions. If unacceptable soil
conditions are exposed mitigation will be recommended.
Foundations shall be reinforced with a minimum of four #5 bars, two top and two bottom, The
structural engineer's recommendations for reinforcement shall be utilized where more severe.
LATERAL DESIGN
Lateral restraint at the base of footings and on slabs may be assumed to be the product of the
dead load and a coefficient of friction of .35. Passive pressure on the face of footings may also be
used to resist lateral forces. A passive pressure of zero at the surface of finished grade, increasing
at the rate of 250 pounds per square foot of depth to a maximum value of 2,500 pounds per
square foot, may be used for compacted fill at this site. If passive pressure and friction are
combined when evaluating the lateral resistance, then the value of the passive pressure should be
limited to 2/3 of the values given above.
RETAINING WALLS
Walls retaining drained earth under static loading may be designed for the following:
Surface Slope; of Reta ped Material
HorizbnWAO Vertical
Equipalent Flutd Prassue Pounds11
=per ubic Foo
Level
31
The point of resultant force under static loading is at H/3 above the base of the retaining wall.
Walls are expected to be six feet or less, higher walls would need to be evaluated based on a site
specific plan.
Retaining walls should include subdrains consisting of four inch, SCH 40 or SDR 35 perforated
pipe surrounded by one cubic foot per lineal foot of/" crushed rock, wrapped with geofabric
cloth. All wall backfill should be compacted to a minimum of 90% relative compaction.
COAST GEOTECHNICAL, INC.
Ms. Adrienne Armstrong 4 W.O. 532917-05
Rough Grade Compaction Report April 20 2018
All retaining structures should include appropriate allowances for anticipated surcharge loading,
where applicable. Retaining walls with an ascending slope condition shall include a minimum
one -foot free board and concrete swale in their design.
Retaining walls shall be waterproofed to the degree desired by the client
FLOOR SLABS
Slab on grades shall be designed in accordance with 2016 CBC codes
Site soils are non plastic
Minimum geotechnical recommendations for slab design are five inches actual thickness with #4
bars at 12 inches on center each way. Slabs shall be tied into perimeter foundations with #4 bars
at 24 inch centers. Structural design may require additional reinforcement and slab thickness.
Subgrade soils shall exhibit a minimum relative compaction of 90% to the depth determined by
the geotechnical engineer. The soil should be kept moist prior to casting the slab. However, if
the soils at grade become disturbed during construction, they should be brought to approximately
optimum moisture content and rolled to a firm, unyielding condition prior to placing concrete.
COAST GEOTECHNICAL, Inc. to verify adequacy of subgrade soils prior to placement of sand
or visqueen.
Section 4.505.2.1 of the California Green Code requires the use of a capillary break between the
slab subgrade and vapor barrier. The capillary break material shall comply with the
requirements of the local jurisdiction and shall be a minimum of four inches in thickness.
Geotechnically coarse clean sand is acceptable; however, some localities require the use of four
inches of gravel (1/2 -inch or larger clean aggregate). If gravels are used, a heavy filter fabric
(Mirafi 140N) shall be placed over the gravels prior to placement of the recommended vapor
barrier to minimize puncturing of the vapor barrier. Additionally, a vibratory plate should be
used over the gravels prior to placement of the recommended filter fabric to smooth out any
sharp protuberances and consolidate the gravels.
Slab areas should be underlain by a vapor retarder consisting of an engineered plastic film (as
described by ASTM:E-1745). In areas where a moisture sensitive floor covering will be used
and/or where moisture infiltration is not desirable, a vapor barrier with a permeance of less than
0.01perms (consistent with ACI 302.2R-06) such as 15 mil. Stego Wrap Vapor Barrier, or
equivalent, should be considered, and a qualified water proofing specialist should be consulted.
The vapor barrier should be underlain by the above described capillary break materials and filter
cloth. The capillary break materials should be compacted to a uniform condition prior to
placement of the recommended filter cloth and vapor barrier. The vapor barrier should be
properly lapped and sealed. Since the vapor barrier will prevent moisture from draining from
fresh concrete, a better concrete finish can usually be obtained if at least two inches of sand is
spread over the vapor barrier prior to placement of concrete.
COAST GEOTECHNICAL, INC.
Ms. Adrienne Armstrong 5 W.O. 532917-05
Rough Grade Compaction Report April 20. 2018
SEISMIC DESIGN
Based on the 2016 CBC the following seismic design parameters are provided. These seismic
design values were determined utilizing latitude 33.595957 and longitude -117.885553 and
calculations from the USGS ground motion parameter calculator. A conservative site class D was
assigned to site earth materials.
• Site Class = D
Mapped 0.2 Second Spectral Response Acceleration, Ss = 1.721 g
• Mapped One Second Spectral Response Acceleration SI = 0.633g
• Site Coefficient from Table 1613A.3.3(1), Fa = 1.0
• Site Coefficient from Table 1613A.3.3(2), Fv = 1.5
Maximum Design Spectral Response Acceleration for short period, SMs = 1.721 g
• Maximum Design Spectral Response Acceleration for one -second period, SMt = 0.949g
• 5% Design Spectral Response Acceleration for short period, SDs = 1.147g
• 5% Design Spectral Response Acceleration for one -second period, SDI = 0.633g
SETTLEMENT
The maximum total post -construction static settlement is anticipated to be on the order of
1/2 inch. Differential settlements are expected to be less than 1/2 inch, measured between
adjacent structural elements over a distance of 40 feet. Seismic induced settlements are addressed
under previous sections.
EXPANSIVE SOILS
Results of expansion tests indicate that the near surface soils have a very low expansion
potential.
UTILITY LINE BACKFILLS
All utility line backfills, both interior and exterior, shall be compacted to a minimum of
90% relative compaction and shall require testing at a maximum of two -foot vertical intervals.
Utility lines shall be placed at appropriate depths. Shallow pipes can be damaged by the forces
imposed by compacting backfill soils. If shallow pipes are not capable of withstanding the forces
of backfill compaction, slurry backfill will be recommended.
HARDSCAPE AND SLABS
Hardscape and slab subgrade areas shall exhibit a minimum of 90% relative compaction to a depth
of at least one foot. Deeper removal and recompaction may be required if unacceptable conditions
are encountered. These areas require testing just prior to placing concrete. Hardscape shall be at
least four inches thick and reinforced with #3 bars on 18 inch centers both ways.
COAST GEOTECHNICAL, INC.
Ms. Adrienne Armstrong 6 W.O. 532917-05
Roueh Grade Compaction Report _ Apri120.2018
CHEMICAL ANALYSIS
An on-site soil sample showed a soluble sulfate content of 30 ppm, which is a negligible sulfate
exposure. Concrete with Type 11 2,500 psi may be utilized; however, the saltwater environ may
cause damage to exposed concrete and a designed concrete should be considered.
DRAINAGE
Positive drainage should be planned for the site. Drainage should be directed away from structures
via non -erodible conduits to suitable disposal areas. The structure should utilize roof gutters and
down spouts tied directly to yard drainage.
Pipes used for storm/site water drainage should be stout enough to withstand the force of
compaction of the soils above. This force can be considerable, causing some weaker pipes to
collapse. Drainage pipes shall have a smooth interior. Pipes with a corrugated interior can cause
the buildup of deleterious matter, which can impede or block the flow of site waters and, as such,
are not recommended. All storm/site water drainage pipes should be in conformance with the
requirements of Table 1102.5 of the 2013 California Plumbing Code.
Unlined flowerbeds, planters, and lawns should not be constructed against the perimeter of the
structure. If such landscaping (against the perimeter of a structure) is planned, it should be properly
drained and lined or provided with an underground moisture barrier. Irrigation should be kept to a
minimum.
Section 1804.4 of the 2016 CBC recommends five percent slope away from structures for
landscape areas within ten feet of the residence. Hardscape areas shall be sloped a minimum of two
percent where within ten feet of the residence unless allowed otherwise by the building official.
Minimum drainage shall be one percent for hardscape areas and two percent for all other areas.
We do not recommend the use of bottomless trench drains to conform with infiltration best
management practice (BMP) such as infiltration trenches, infiltration basins, dry wells, permeable
pavements or similar systems designed primarily to percolate water into the subsurface soils within
five feet of foundations. Due to the physical characteristics of the site earth materials, infiltration of
waters into the subsurface earth materials has a risk of adversely affecting below grade structures,
building foundations and slabs, and hardscape improvements. From a geotechnical viewpoint
surface drainage should be directed to the street.
The WQMP requirement shall be addressed by the Civil Engineer.
POST -GRADING SERVICES
During construction of the residence, it is recommended, and at times required by the regulatory
agency, the following be observed and/or tested by the geotechnical engineer:
• Excavation of footings
•
Backfill of interior trenches
COAST GEOTECHNICAL, INC.
Ms. Adrienne Armstrong 7 W.O. 532917-05
Rough Grade Compaction Report April 20 2018
• Testing of interior and exterior slab areas
• Backfill of exterior utility trenches
• Hardscape subgrade
It is the responsibility of the developer to schedule the required observations and testing.
REGULATORY COMPLIANCE
I hereby certify that the subject grading was observed by a representative from this office, and
the work was done in full compliance with the Grading Ordinance of the City of Newport Beach
and in accordance with the best accepted practices of the applicable chapter of the California
Building Code.
All cuts, fills or processing of original ground under the purview of this report have been
completed under the observation of and with selective testing by COAST GEOTECHNICAL,
INC. and found to be in compliance with the Grading Code of the City of Newport Beach. The
completed work has been observed by COAST GEOTECHNICAL, INC. and is considered
adequate for the development. Our findings were made and recommendations prepared in
accordance with generally accepted professional engineering practices, and no further warranty
is implied nor made.
This report is subject to review by the controlling authorities for this project.
We appreciate this opportunity to be of service to you.
Respectfully submitted:
COAST GEOTECHNICAL, INC.
Ming-Tamg Chen
RCE 54011
No. 54011
Exp. 12/31/19
COAST GEOTECHNICAL, INC.
Ms. Adrienne Armstrong 8 W.O. 532917-05
Rough Grade Compaction Report April 20 2018
COMPACTION TEST RESULTS
TABLE 1
gest
No
Locationoposad''
Below
Grade �fi� -
Moisture
Content'
%
Dry Unit
Weight
(Ibs/ft3)
Soil
T
Relative `
Compaction '
; bate
1
Pad Area
3.03.5
10.5
101.9
I
91.0
4/4/18
2
Pad Area
3.03.5
10.4
102.0
I
91.1
4/4/18
3
Pad Area
3.03.5
10.9
101.7
I
90.8
4/5/18
4
Pad Area
1.52.0
9.9
104.8
II
91.1
4/5/18
5
Pad Area
1.52.0
9.5
105.8
II
92.0
4/5/18
6
Pad Area
1.52.0
9.7
104.9
II
91.2
4/5/18
7
Pad Area
3.03.5
11.2
102.1
I
91.2
4/9/18
8
Pad Area
2.53.0
10.5
102.0
I
91.1
4/10/18
9
Pad Area
1.01.5
10.7
105.2
II
91.5
4/10/18
10
Pad Area
0.51.0
10.0
105.8
II
92.0
4/11/18
11
Pad Area
F.G.
9.5
106.4
II
92.5
4/13/18
12
Pad Area
F.G.
10.0
105.7
II
91.9
4/13/18
13
Pad Area
F.G.
9.8
106.1
11
92.3
4/13/18
F.G.: finish grade
SITE PLAN
Scale: 1 16'
Alley
He
7
Approximate
Oji j9°a, Compaction
Test Location
5
------ -----
9 Approximate
Limits of Grading
T
N
-nm
10
1* iNOdJ NV330 1SV3 or
•
IN I ST -1
Geotechnical Engineering Investigation Work Order 532917-05
2038 East Ocean Front
Newport Beach, California Plate No. I
COAST GEOTECHNICAL. INC.
COAST GEOTECHNICAL, INC.
1200 W. Commonwealth Avenue, Fullerton, CA • 92833 • Ph:(714) 870-1211 • Fax (714) 870-1222 - E-mail:coastgCotec@sbcglobat.net
sbcglobat.net
July 16, 2019
Ms. Adrienne Armstrong
2038 East Ocean Front
Newport Beach, CA 92663
References:
W.O. 532917-06
Subject: Final Soils Report for New Residence at
2038 East Ocean Front, Newport Beach,
California
1. Geotechnical Engineering Investigation for Proposed New Residence, 2038 East Ocean Front,
NewportBeach, California; by Coast Geotechnical, Inc., W.O. 532917-01, dated May 31, 2017.
2. Geotechnical Addendum Report for Basement Construction for Proposed New Residence at 2038
East Ocean Front, Newport Beach, California; by Coast Geotechnical, Inc., W.O. 532917-02, dated
August 14, 2017.
3. Geotechnical Opinion Concerning the Proposed Infiltration Design for the 2038 East Ocean Front,
Newport Beach, California; by Coast Geotechnical, Inc., W.O. 532917-03, dated October 11, 2017.
4. Response to Geotechnical Report Review Comments for 2038 East Ocean Front, Newport Beach,
California; by Coast Geotechnical, Inc., W.O. 532917-04, dated March 2, 2018.
5. Rough Grade Compaction Report for Proposed New Residence at 2038 East Ocean Front, Newport
Beach, California; by Coast Geotechnical, Inc., W.O. 532917-05, dated April 20, 2018.
Dear Ms. Armstrong:
In accordance with the your request, this final soils report has been prepared to address
geotechnical observations and testing performed during construction of the residence. This report
addresses the requirements of the City of Newport Beach.
FOUNDATION EXCAVATIONS
Foundation excavations for the residence were observed on April 25, 2018 and June 15 & 22,
2018. The footings excavations were found to be acceptable at the time of our observations.
INTERIOR SLAB SUB GRADE
The interior slab subgrade was observed on June 14 & 15, 2018 and July 2, 2018. Probing and
testing of the interior residential slab area indicated acceptable geotechnical conditions for
support of the proposed slab at the time of our observations.
COAST GEOTECHNICAL, INC
Ms. Armstrong 2 W.O. 532917-06
Final Soils Report July 16, 2019
EXTERIOR HARDSCAPE SUBGRADE
The exterior hardscape subgrade for the sidewalks and patio areas was observed on March 3,
2019 and July 15, 2019 and found to be geotechnically acceptable for support of the proposed
hardscape.
OPINION
It is opinion of COAST GEOTECHNICAL, INC. that the summarized geotechnical conditions
approved by this office are in compliance with approved geotechnical reports and Newport
Beach building codes. The final grades appear to conform to approved plans.
We appreciate this opportunity to be of service to you.
Respectfully Submitted:
COAST GEOTECHNICAL, INC.
Ming-Tarng Chen
PRN
RCE 54011 c
No. 54011
Exp. 12/31/19
4e, E. Herc
--�4-1
Staff Geologist