HomeMy WebLinkAboutX2017-3155 - Soils (3)NorCal Engineering
Soils and Geotechnical Consultants
10641 Humbolt Street Los Alamitos, CA 90720
(562) 799-9469 Fax (562) 799-9459
March 29, 2018
Darsi Rubin
707 Bellis Street
Newport Beach, California 92660
40&7- 3055
IMsGnJCn511L
Project Number 19541-17
Permit No: 3155
RE: Geotechnical Grading Report - Observation and Testing for Proposed
Residential Development - Located at 1212 Sandcastle Drive, Corona Del
Mar, in the City of Newport Beach, California
Dear Ms. Rubin:
Pursuant to your request, this firm has provided this geotechnical report to summarize
the observation and testing performed during grading operations at the above
referenced project. The geotechnical aspects of the grading were conducted in
accordance with our report titled "Geotechnical Engineering Investigation", dated April
19, 2017, Project Number 19541-17. Our geotechnical services pertaining to the
grading of the project development are summarized in the subsequent sections of this
report.
Site Gradinaa
The purpose of the grading operations was for the placement of fill to provide structural
support of the proposed development. All vegetation and demolition debris was stripped
and removed from the fill area prior to the placement of any fill soils. The upper low
density surface soils were removed to competent native material, the exposed surface
scarified, moisture conditioned and then recompacted to a minimum of 90% relative
compaction.
March 29, 2018 Project Number 19541-17
Page 2
In the opinion of this firm, the native soils are suitable to support the placement of fill
material. Grading extended a minimum of five horizontal feet or to the depth of fill
placed, whichever is greater, beyond the edge of the proposed foundations.
Fill soils placed were compacted to a minimum 90% of the laboratory standard in lifts
not in excess of eight inches in thickness. The maximum depth of fill soils placed was
approximately 1'% feet in the building pad area. A track loader was utilized for
compaction control. A water hose provided moisture control. Our services did not
include any surveying of excavation bottoms, building corners, or subgrade elevations
during grading operations.
Laboratory/Field Testina
The relative compaction was determined by Sand Cone Method (ASTM: D1556-07) and
by the Drive Tube Method (ASTM: D2937-10). The maximum density was obtained by
the laboratory standard (ASTM: D1557-12) and results are shown on Table I. A
summary of the compaction tests are described in Appendix B with locations shown on
the accompanying plans. Additional laboratory tests were performed on representative
bulk bag samples of the near surface soils at the completion of backfill operations. The
tests consisted of the following:
A. Expansion index tests in accordance with ASTM D 4829 were performed on
remolded samples of the upper soils to determine the expansive characteristics
and to provide any necessary recommendations for reinforcement of the slabs -
on -grade and the foundations. Results of these tests are provided on Table II in
Appendix A.
B. Soluble sulfate tests in accordance with California Test Method 417 were
performed on representative soils samples to estimate the potential for corrosion
of concrete in contact with the on-site soils. Results are provided on Table III in
Appendix A.
NorCal Engineering
March 29, 2018
Page 5
Expansive Soil Guidelines
Project Number 19541-17
The following expansive soil guidelines are provided for your project. The intent of
these guidelines is to inform you, the client, of the importance of proper design and
maintenance of projects supported on expansive soils. You, as the owner or other
interested party, should be warned that you have a duty to provide the
information contained in the soil report including these guidelines to your design
engineers, architects, landscapers and other design parties in order to enable
them to provide a design that takes into consideration expansive soils.
In addition, you should provide the soil report with these guidelines to any property
manager, lessee, property purchaser or other interested party that will have or assume
the responsibility of maintaining the development in the future.
Expansive soils are fine-grained silts and clays which are subject to swelling and
contracting. The amount of this swelling and contracting is subject to the amount of
fine-grained clay materials present in the soils and the amount of moisture either
introduced or extracted from the soils. Expansive soils are divided into five categories
ranging from 'very low" to "very high". Expansion indices are assigned to each
classification and are included in the laboratory testing section of this report. If the
expansion index of the soils on your site, as stated in this report, is 21 or higher, you
have expansive soils. The classifications of expansive soils are as follows:
Classification of Expansive Soil*
Expansion Index
Potential Expansion
0-20
Very Low
21-50
Low
51-90
Medium
91-130
High
Above 130
Very High
*From Table 18A -1-B of California Building Code (1988)
When expansive soils are compacted during site grading operations, care is taken to
place the materials at or slightly above optimum moisture levels and perform proper
compaction operations. Any subsequent excessive wetting and/or drying of expansive
soils will cause the soil materials to expand and/or contract. These actions are likely to
cause distress of foundations, structures, slabs -on -grade, sidewalks and pavement over
the life of the structure. it is therefore imperative that even after construction of
improvements, the moisture contents are maintained at relatively constant levels,
allowing neither excessive wetting or drying of soils.
NorCal Engineering
March 29, 2018 Project Number 19541-17
Page 6
Evidence of excessive wetting of expansive soils may be seen in concrete slabs, both
interior and exterior. Slabs may lift at construction joints producing a trip hazard or may
crack from the pressure of soil expansion. Wet clays in foundation areas may result in
lifting of the structure causing difficulty in the opening and closing of doors and windows,
as well as cracking in exterior and interior wall surfaces. In extreme wetting of soils to
depth, settlement of the structure may eventually result. Excessive wetting of soils in
landscape areas adjacent to concrete or asphaltic pavement areas may also result in
expansion of soils beneath pavement and resultant distress to the pavement surface.
Excessive drying of expansive soils is initially evidenced by cracking in the surface of
the soils due to contraction. Settlement of structures and on -grade slabs may also
eventually result along with problems in the operation of doors and windows.
Projects located in areas of expansive clay soils will be subject to more movement and
"hairline" cracking of walls and slabs than similar projects situated on non -expansive
sandy soils. There are, however, measures that developers and property owners may
take to reduce the amount of movement over the life the development. The following
guidelines are provided to assist you in both design and maintenance of projects on
expansive soils:
Drainage away from structures and pavement is essential to prevent
excessive wetting of expansive soils. Grades of at least 3% should be
designed and maintained to allow flow of irrigation and rain water to
approved drainage devices or to the street. Any "ponding" of water adjacent
to buildings, slabs and pavement after rains is evidence of poor drainage; the
installation of drainage devices or regrading of the area may be required to
assure proper drainage. Installation of rain gutters is also recommended to
control the introduction of moisture next to buildings. Gutters should
discharge into a drainage device or onto pavement which drains to roadways.
Irrigation should be strictly controlled around building foundations, slabs and
pavement and may need to be adjusted depending upon season. This
control is essential to maintain a relatively uniform moisture content in the
expansive soils and to prevent swelling and contracting. Over -watering
adjacent to improvements may result in damage to those improvements.
NorCal Engineering makes no specific recommendations regarding
landscape irrigation schedules.
Planting schemes for landscaping around structures and pavement should
be analyzed carefully. Plants (including sod) requiring high amounts of water
may result in excessive wetting of soils. Trees and large shrubs may actually
extract moisture from the expansive soils, thus causing contraction of the
fine-grained soils.
NorCal Engineering
NorCal Engineering
_ I
SANDCASTLE DRIVE
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NorCal. Engineering
SOS S AND GicQgT-CI-DUCAL CONSULTANTS
DARSI RUBIN
ROJECT 19541-17 GATE MARCH 2018
L'OCATIOf7 OF 00WACTION TESTS
March 29, 2018
Page 7
Project Number 19541-17
Thickened edges on exterior slabs will assist in keeping excessive moisture
from entering directly beneath the concrete. A six-inch thick or greater
deepened edge on slabs may be considered. Underlying interior and exterior
slabs with 6 to 12 inches or more of non -expansive soils and providing
presaturation of the underlying clayey soils as recommended in the soil
report will improve the overall performance of on -grade slabs.
Increase the amount of steel reinforcing in concrete slabs, foundations and
other structures to resist the forces of expansive soils. The precise amount
of reinforcing should be determined by the appropriate design engineers
and/or architects.
• Recommendations of the soil report should always be followed in the
development of the project. Any recommendations regarding presaturation
of the upper subgrade soils in slab areas should be performed in the field
and verified by the Soil Engineer.
NorCal Engineering
APPENDICES
(In order of appearance)
Appendix A— Laboratory Tests
Table I - Maximum Density Tests
Table 11- Expansion IndexTests
Table III - Sulfate Tests
Appendix B - Summary of Compaction Tests
Site Plan
Summary of Compaction Tests
NorCal Engineering
Appendix A
NorCal Engineering
March 29, 2018 Project Number 19541-17
Page 8
TABLE
MAXIMUM DENSITY TESTS
(STM: D1667-121"
Optimum Maximum Dry
Sam le Classification Moisture Density (lbs./cu:ft,)
I Clayey SILTSTONE 21.0 94.0
II Silty CLAY 18.0 06.5
III Silty CLAY 17.0 100:0
TABLE II
EXPANSION INDEX TESTS
Expansion
Sample Classification Index
Pad Subgrade Silty CLAY 90
TABLE 111
SULFATE TESTS
Sample
Pad Subgrade
Sulfate I% by Weight)
0.006
NorCal Engineering
March 29, 2018
Project Number 19541-17
Page 9
SUMMARY OF COMPACTION TEST RESULTS
Date of
Test
Percent
Unit Wt.
Relative Soil
Test
Test
No.
Location,
Depth
Moisture
lbs./cu.ft.
Compaction Tyne
1/12/18
101
Site Grading
1.5-2.0
19.5
88.5
94 I
S
1/12/18
102
Site Grading
1.5-2.0
20.1
87.1
93 1
S
1/19/18
103
Site Grading
0.0-0.5
16.8
92.3
96 II
D
1/19/18
104
Site Grading
0.0-0.5
17.8
93.4
93 III
D
2/21/18
105
Sewer Backfill
0.0-0.5
18.5
91.3
91 III
S
2/21/18
106
Sewer Backfill
0.0-0.5
17.9
89.9
93 II
S
2/21/18
107
Sewer Backfill
0.0-0.5
19.1
92.6
93 111
S
"Retest of failing tests after area reworked
S= Sand Cone Method
D= Drive Tube Method
NorCal Engineering
March 29, 2018 Project Number 19541-17
Page 3
Foundation Design
All new and existing foundations shall be designed utilizing a safe bearing capacity of
1,800 psf for an embedded depth of 24 inches entirely into approved engineered fill or
competent bedrock. A one-third increase may be used when considering short term
loading from wind and seismic forces. All continuous foundations shall be reinforced a
minimum of two No. 4 bars, top and bottom and shall be in accordance with Section
1808.6 of 2016 CBC using an effective plasticity index of 30.
In addition, foundation excavations observed and approved by a representative of this
firm prior to pouring concrete were embedded into competent bearing material
Slab Design
All new concrete slabs -on -grade including driveway and hardscape shall be at least four
inches in thickness reinforced a minimum of No. 3 bars, sixteen inches in each direction
positioned in the center of the slab and placed on approved subgrade soils. The
subgrade soils shall be moisture conditioned to optimum moisture levels in the upper
eighteen inches. A vapor retarder should be utilized in areas which would be sensitive to
the infiltration of moisture.
This retarder shall meet requirements of ASTM E 96, Water Vapor Transmission of
Materials and ASTM E 1745, Standard Specification for Water Vapor Retarders used in
Contact with Soil or Granular Fill Under Concrete Slabs. The vapor retarder shall be
installed in accordance with procedures stated in ASTM E 1643, Standard practice for
Installation of Water Vapor Retarders used in Contact with Earth or Granular Fill Under
Concrete Slabs.
The moisture retarder may be placed directly upon moisture conditioned approved
subgrade soils, although one to two inches of sand beneath the membrane is desirable.
The subgrade upon which the retarder is placed shall be smooth and free of rocks,
gravel or other protrusions which may damage the retarder. Use of sand above the
retarder is under the purview of the structural engineer; if sand is used over the retarder,
it should be placed in a dry condition.
NorCal Engineering
March 29, 2018 Project Number 19541-17
Page 4
Corrosion Desion Criteria
Representative samples of the surficial soils revealed negligible sulfate concentrations.
Therefore, all concrete in contact with on site soils shall be designed in accordance with
Table 4.3.1 of ACI 318 Building Code and Commentary. Sulfate test results may be
found on the attached Table III.
Expansive Soil
On-site soils are moderate in expansion (EI < 51-90). When soils have an expansion
index (EI) of 20 or more, special attention should be given to the project design and
maintenance. The attached Expansive Soil Guidelines should be reviewed by the
engineers, architects, owner, maintenance personnel and other interested parties and
considered during the design of the project and future property maintenance.
Limitations
It should be noted that our work does not warrant or guarantee that the contractor
responsible for each phase of the project has performed his work in accordance with the
project specifications.
We appreciate this opportunity to be of service to you. If you have any further
questions, please do not hesitate to contact the undersigned.
Respectfully submitted , �j-ESS�gM
NORCAL ENGINEETUc��yc�
-� i , . � I S'� [ ; �._. ��.'i '{-No.f9A'i r-"� _ �,• �" r _ <)...�-_
Keith D. Tucker . ` Euo �2aau�a vx Michael A Barone
Project Engineer ix Project Project Manager
R.G.E. 841
NorCal Engineering
NorCal Engineering
Soils and Geotechnical Consultants
10641 Humbolt Street Los Alamitos, CA 90720
(562)799-9469 Fax (562)799-9459
July 23, 2019
Darsi Rubin
707 Bellis Street
Newport Beach, California 92660
Project Number 19541-17
Permit No: 3155
RE: Updated Geotechnical Grading Report — Observation and Testing for
Proposed Retaining Wall Development - Located at 1212 Sandcastle
Drive, Corona Del Mar, in the City of Newport Beach, California
Dear Ms. Rubin:
Pursuant to your request, this firm has provided this updated geotechnical report to
summarize the observation and testing performed during grading operations including
the new retaining wall along the east property line at the above referenced project. The
geotechnical aspects of the grading were conducted in accordance with our report titled
"Geotechnical Engineering Investigation", dated April 19, 2017, Project Number 19541-
17. Our geotechnical services pertaining to the grading of the project development are
summarized in the subsequent sections of this report.
Site Grading
The purpose of the grading operations was for the placement of fill to provide structural
support of the proposed development. All vegetation and demolition debris was stripped
and removed from the fill area prior to the placement of any fill soils. The upper low
density surface soils were removed to competent native material, the exposed surface
scarified, moisture conditioned and then recompacted to a minimum of 90% relative
compaction.
Q.
l`
July 23, 2019 Project Number 19541-17
Page 2
In the opinion of this firm, the native soils are suitable to support the placement of fill
C`
material. Grading extended a minimum of five horizontal feet or to the depth of fill
placed, whichever is greater, beyond the edge of the proposed foundations.
Fill soils placed were compacted to a minimum of 90% of the laboratory standard in lifts
not in excess of eight inches in thickness. The maximum depth of fill soils placed was
approximately 1 '/2 feet in the building pad area. A track loader was utilized for
compaction control. A water hose provided moisture control. Our services did not
include any surveying of excavation bottoms, building corners, or subgrade elevations
during grading operations.
Retainina Wall Backfill
A new retaining wall was constructed along the east property line. Foundation
excavations for the new retaining wall observed by a representative of this firm were
found to be embedded into competent bearing material. A 4 -inch diameter perforated
drain line was placed behind the new retaining wall. The retaining wall was backfilled
utilizing % inch diameter gravel to approximately 18 inches below grade. The gravel
was overlain with a filter fabric prior to the placement of compacted fill soil. On-site fill
soils placed on top of the gravel backfill were compacted to a minimum of 90% relative
compaction. The maximum depth of fill soils placed behind the new retaining wall was
approximately 4 feet. Hand operated equipment was utilized for compaction control. A
water hose provided moisture control.
Laboratory/Field Testina
The relative compaction was determined by Sand Cone Method (ASTM: D1556) and by
the Drive Tube Method (ASTM: D2937). The maximum density of the fill soils was
obtained by the laboratory standard (ASTM: D1557) and results are shown on Table 1.
Tests were performed a minimum of every 500 cubic yards placed and every two feet in
depth of fill placed. A summary of the compaction tests of the site grading operations
are described in Appendix B with locations shown on the accompanying plan. Additional
laboratory tests were performed on representative bulk bag samples of the near surface
soils at the completion of precise grading operations. The tests consisted of the
following:
NorCal Engineering
` July 23, 2019 Project Number 19541-17
Page 3
r
A. Expansion index tests in accordance with the ASTM D 4829 were performed on
remolded samples of the upper soils to determine the expansive characteristics and
to provide any necessary recommendations for reinforcement of the slabs -on -grade
and the foundations. Results of these tests are provided on Table II in Appendix A.
B. Soluble sulfate tests in accordance with California Test Method 417 were performed
on representative soils samples to estimate the potential for corrosion of concrete in
contact with the on-site soils. Results are provided on Table III in Appendix A.
Foundation Desisan
All new and existing foundations shall be designed utilizing an allowable soil bearing
capacity of 1,800 psf for an embedded depth of 24 inches entirely into approved
engineered fill or competent bedrock. A one-third increase may be used when
considering short term loading from wind and seismic forces. All continuous foundations
shall be reinforced a minimum of two No. 4 bars, top and bottom and shall be in
accordance with Section 1808.6 of 2016 CBC using an effective plasticity index of 30.
In addition, foundation excavations observed by a representative of this firm were found
to be embedded into competent bearing material.
Slab Design
All new concrete slabs -on -grade including driveway and hardscape shall be at least four
inches in thickness reinforced a minimum of No. 3 bars, sixteen inches in each direction
positioned in the center of the slab and placed on approved subgrade soils. The
subgrade soils shall be moisture conditioned to optimum moisture levels in the upper
eighteen inches. A vapor retarder should be utilized in areas which would be sensitive
to the infiltration of moisture.
NorCal Engineering
July 23, 2019 Project Number 19541-17
Page 4
r
This retarder shall meet requirements of ASTM E 96, Water Vapor Transmission of
Materials and ASTM E 1745, Standard Specification for Water Vapor Retarders used in
Contact with Soil or Granular Fill Under Concrete Slabs. The vapor retarder shall be
installed in accordance with procedures stated in ASTM E 1643, Standard practice for
Installation of Water Vapor Retarders used in Contact with Earth or Granular Fill Under
Concrete Slabs.
The moisture retarder may be placed directly upon compacted subgrade, although 2
inches of sand beneath the membrane is desirable. The subgrade upon which the
retarder is placed shall be smooth and free of rocks, gravel or other protrusions which
may damage the retarder. Use of sand above the retarder is under the purview of the
structural engineer; if sand is used over the retarder, it should be placed in a dry
condition.
Expansive Soil
On-site soils are moderate in expansion (Expansion Index < 51-90). When soils have
an expansion index (EI) of 20 or more, special attention should be given in the project
design and maintenance. The attached Expansive Soil Guidelines should be reviewed
by the engineers, architects, owner, maintenance personnel and other interested parties
and considered during the design of the project and future property maintenance.
Corrosion Design Criteria
Representative samples of the surficial soils, typical of the subgrade soils expected to
be encountered within foundation excavations, revealed negligble sulfate
concentrations. Therefore, all concrete in contact with on site soils shall be designed in
accordance with Table 19A -A-4 of the latest building code. Sulfate test results may be
found on the attached Table III.
Limitations
It should be noted that our work does not warrant or guarantee that the contractor
responsible for each phase of the project has performed his work in accordance with the
project specifications.
NorCal Engineering
July 23, 2019 Project Number 19541-17
Page 5
We appreciate this opportunity to be of service to you. If you have any further
C'
questions, please do not hesitate to contact the undersigned.
Respectfully
NORCAL EN
Keith D. Tuc4
Project Engir
R.G.E. 841
NorCal Engineering
Mike A. Barone
Project Manager
C�
July 23, 2019 Project Number 19541-17
Page 6
Expansive Soil Guidelines
The following expansive soil guidelines are provided for your project. The intent of
these guidelines is to inform you, the client, of the importance of proper design and
maintenance of projects supported on expansive soils. You, as the owner or other
interested party, should be warned that you have a duty to provide the
Information contained in the soil report including these guidelines to your design
engineers, architects, landscapers and other design parties in order to enable
them to provide a design that takes into consideration expansive soils.
In addition, you should provide the soil report with these guidelines to any property
manager, lessee, property purchaser or other interested party that will have or assume
the responsibility of maintaining the development in the future.
Expansive soils are fine-grained silts and clays which are subject to swelling and
contracting. The amount of this swelling and contracting is subject to the amount of
fine-grained clay materials present in the soils and the amount of moisture either
introduced or extracted from the soils. Expansive soils are divided into five categories
ranging from "very low' to 'very high". Expansion indices are assigned to each
classification and are included in the laboratory testing section of this report. If the
expansion index of the soils on your site, as stated in this report, is 21 or higher, you
have expansive soils. The classifications of expansive soils are as follows:
Classification of Expansive Soil*
Expansion Index
Potential Expansion
0-20
Very Low
21-50
Low
51-90
Medium
91-130
High
Above 130
Very High
*From Table 18A -1-B of California Building Code (1988)
When expansive soils are compacted during site grading operations, care is taken to
place the materials at or slightly above optimum moisture levels and perform proper
compaction operations. Any subsequent excessive wetting and/or drying of expansive
soils will cause the soil materials to expand and/or contract. These actions are likely to
cause distress of foundations, structures, slabs -on -grade, sidewalks and pavement over
the life of the structure. It is therefore imperative that even after construction of
improvements, the moisture contents are maintained at relatively constant levels,
allowing neither excessive wetting or drying of soils.
NorCal Engineering
L,
July 23, 2019 Project Number 19541-17
Page 7
Evidence of excessive wetting of expansive soils may be seen in concrete slabs, both
interior and exterior. Slabs may lift at construction joints producing a trip hazard or may
crack from the pressure of soil expansion. Wet clays in foundation areas may result in
lifting of the structure causing difficulty in the opening and closing of doors and windows,
as well as cracking in exterior and interior wall surfaces. In extreme wetting of soils to
depth, settlement of the structure may eventually result. Excessive wetting of soils in
landscape areas adjacent to concrete or asphaltic pavement areas may also result in
expansion of soils beneath pavement and resultant distress to the pavement surface.
Excessive drying of expansive soils is initially evidenced by cracking in the surface of
n. Settlement of structures and on -grade slabs may also
e to contraction. Y
the soils du 9
eventually result along with problems in the operation of doors and windows.
Projects located in areas of expansive clay soils will be subject to more movement and
"hairline" cracking of walls and slabs than similar projects situated on non -expansive
sandy soils. There are, however, measures that developers and property owners may
take to reduce the amount of movement over the life the development. The following
guidelines are provided to assist you in both design and maintenance of projects on
expansive soils:
Drainage away from structures and pavement is essential to prevent
excessive wetting of expansive soils. Grades of at least 3% should be
designed and maintained to allow flow of irrigation and rain water to
approved drainage devices or to the street. Any "ponding" of water adjacent
to buildings, slabs and pavement after rains is evidence of poor drainage; the
installation of drainage devices or regrading of the area may be required to
assure proper drainage. Installation of rain gutters is also recommended to
control the introduction of moisture next to buildings. Gutters should
discharge into a drainage device or onto pavement which drains to roadways.
Irrigation should be strictly controlled around building foundations, slabs and
pavement and may need to be adjusted depending upon season. This
control is essential to maintain a relatively uniform moisture content in the
expansive soils and to prevent swelling and contracting. Over -watering
adjacent to improvements may result in damage to those improvements.
NorCal Engineering makes no specific recommendations regarding
landscape irrigation schedules.
Planting schemes for landscaping around structures and pavement should
be analyzed carefully. Plants (including sod) requiring high amounts of water
may result in excessive wetting of soils. Trees and large shrubs may actually
extract moisture from the expansive soils, thus causing contraction of the
fine-grained soils.
NorCal Engineering
July 23, 2019 Project Number 19541-17
Page 8
• Thickened edges on exterior slabs will assist in keeping excessive moisture
from entering directly beneath the concrete. A six-inch thick or greater
deepened edge on slabs may be considered. Underlying interior and exterior
slabs with 6 to 12 inches or more of non -expansive soils and providing
presaturation of the underlying clayey soils as recommended in the soil
report will improve the overall performance of on -grade slabs.
• Increase the amount of steel reinforcing in concrete slabs, foundations and
other structures to resist the forces of expansive soils. The precise amount
of reinforcing should be determined by the appropriate design engineers
and/or architects.
• Recommendations of the soil report should always be followed in the
development of the project. Any recommendations regarding presaturation
of the upper subgrade soils in slab areas should be performed in the field
and verified by the Soil Engineer.
NorCal Engineering
r,
APPENDICES
(In order of appearance)
Appendix A — Laboratory Tests
Table I - Maximum Density Tests
Table II — Expansion Index Tests
Table III - Sulfate Tests
Appendix B — Summary of Compaction Tests
Site Plan
Summary of Compaction Tests
NorCal Engineering
APPENDIX A
NorCal Engineering
July 23, 2019 Project Number 19541-17
Page 9
TABLE
MAXIMUM DENSITY TESTS
(ASTM: D1557)
Optimum
Maximum Dry
Sample Classification
Moisture
Density (lbs./cu.ft.)
I Clayey SILTSTONE
21.0
94.0
II Silty CLAY
18.0
96.5
III Silty CLAY
17.0
100.0
TABLE II
EXPANSION INDEX TESTS
Expansion
Sample Classification Index
Pad Subgrade Silty CLAY 90
TABLE III
SULFATE TESTS
Sample
Pad Subgrade
Sulfate (% by Weight)
0.006
NorCal Engineering
C-
APPENDIX B
NorCal Engineering
�a
SANDCASTLE DRIVE
rvUUA'YAIf I, -
PA
v
$3 a .��a9har rh _�,... .
------------ - U.
'.
NEW RETAINING WALL
i"=20'
no
r
O
0
V-.1 APROXIMATE LIMITS OF GRADING
S=SEWER
NorCal Engineering
SOS S AND ATE'QTEE..CIU�TICALICONSIJL'IANTS Loob.Tloti OF CiJWAI;T11DF8 TESTS
DARSI RUBIN
C_. PROJECT 1 9541-1 7 1 WE JULY 2019
July 23, 2019 Project Number 19541-17
Page 10
SUMMARY OF COMPACTION TEST RESULTS
Date of
Test
Percent
Unit Wt.
Relative Soil
Test
Test
No.
Location
Depth
Moisture
lbs./cu.ft.
Compaction Type
S/D
1/12/18
101
Site Grading
1.5-2.0
19.5
88.5
94 1
S
1/12/18
102
Site Grading
1.5-2.0
20.1
87.1
93 1
S
1/19/18
103
Site Grading
0.0-0.5
16.8
92.3
96 II
D
1/19/18
104
Site Grading
0.0-0.5
17.8
93.4
93 111
D
2/21/18
105
Sewer Backfill
0.0-0.5
18.5
91.3
91 111
S
2/21/18
106
Sewer Backfill
0.0-0.5
17.9
89.9
93 11
S
2/21/18
107
Sewer Backfill
0.0-0.5
19.1
92.6
93 III
S
6/30/18
108
Wall Backfill
0.0-0.5
19.0
90.0
93 11
D
"Retest of failing tests after area reworked
S=Sand Cone Method
D=Drive Tube Method
NorCal Engineering