final geotechnical engineering report - yorke & curtis consultants, inc. 12400 se freeman way,...
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Terracon Consultants, Inc. 12400 SE Freeman Way, Suite 102 Portland, Oregon 97222
P [503] 659 3281 F [503] 659 1287 terracon.com
Final Geotechnical Engineering Report Proposed Walmart Neighborhood Market #5995-00
17711 Jean Way
Lake Oswego, Oregon
March 16, 2012
Project No. 82105050
Prepared for:
PACLAND and
Wal-Mart Stores, Inc.
Prepared by:
Terracon Consultants, Inc.
Portland, Oregon
TABLE OF CONTENTS
Page
EXECUTIVE SUMMARY i
1.0 INTRODUCTION 1
2.0 PURPOSE AND SCOPE 1
3.0 PROJECT INFORMATION 2
3.1 Site Location ......................................................................................................... 2
3.2 Project Description ............................................................................................... 2
4.0 SITE CONDITIONS 2
5.0 SUBSURFACE CONDITIONS 3
5.1 Published Geologic Literature ............................................................................. 3
5.2 Subsurface Explorations ...................................................................................... 4
5.3 Generalized Subsurface Profile ........................................................................... 4
5.4 Groundwater ......................................................................................................... 6
5.5 Geologic Hazards ................................................................................................. 6
6.0 CLIMATE DATA 7
7.0 LABORATORY TESTING 7
7.1 Topsoil Testing ..................................................................................................... 8
7.2 Soil Corrosion Potential ....................................................................................... 8
8.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION 9
8.1 Geotechnical Considerations .............................................................................. 9
8.2 Earthwork ............................................................................................................ 10
8.2.1 Site Preparation 10
8.2.2 Subgrade Preparation 11
8.2.3 Fill Materials and Placement 13
8.3 Temporary and Permanent Slopes .................................................................... 15
8.3.1 Safety 15
8.3.2 Temporary Cut Slope Inclinations 15
8.4 Foundations ........................................................................................................ 16
8.4.1 Foundation Design Recommendations 16
8.4.2 Foundation Construction Considerations 17
8.5 Floor Slab ............................................................................................................ 18
8.5.1 Floor Slab Design Recommendations 18
8.5.2 Floor Slab Construction Considerations 19
8.6 Utility Trenching and Backfilling ....................................................................... 19
8.6.1 Utility Trenching 19
8.6.2 Utility Subgrade Preparation 19
8.6.3 Pipe Bedding 19
8.6.4 Trench Backfill 20
8.7 Pavements ........................................................................................................... 20
TABLE OF CONTENTS
Page
8.7.1 Existing Pavement Conditions 20
8.7.2 Pavement Repair/Preparation 20
8.7.3 Design Recommendations 22
8.7.4 Asphalt and Base Course Materials 24
8.7.5 Concrete Properties and Materials 24
8.7.6 Construction Considerations 25
9.0 GENERAL COMMENTS 25
APPENDIX A – FIELD EXPLORATION
Site and Exploration Plan (Exhibit A-1)
Pavement Condition Observations, Dec. 2010 (Exhibit A-2)
Field Exploration Description
Exploration Location Data (Northings, Eastings, Ground Elevations)
Boring Logs P-1 to P-7, C-1 to C-2
APPENDIX B – LABORATORY TESTING
Laboratory Testing
APPENDIX C – SOIL & ROCK CLASSIFICATION
General Notes
Unified Soil Classification System
APPENDIX D – PROJECT EXHIBITS
Typical Asphalt Pavement Sections (Exhibit D-1)
Typical Concrete Pavement Sections (Exhibit D-2)
APPENDIX E – SUPPORTING DOCUMENTS
WRCC Summary
AASHTO Pavement Design Calculations
Geotechnical Investigation Fact Sheet
Foundation Design Criteria
Foundation Subsurface Preparation Note
Final Geotechnical Engineering Report Proposed Neighborhood Market #5995-00 ■ Lake Oswego, Oregon March 16, 2012 ■ Terracon Project No. 82105050
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EXECUTIVE SUMMARY
The parking lot and interior floor slab subsurface conditions at the site were evaluated to
develop geotechnical related design and construction recommendations for site improvements.
Based on the subsurface conditions and our understanding of the proposed construction, the
primary geotechnical considerations associated with the proposed project are summarized
below.
Pavements: The parking lot pavement is in fair condition and appears to be the
original, approximately 13-year-old pavement, based on the absence of patches, crack
sealant, and apparent lack of overlays observed in the 2½- to 4-inch thick asphalt
cores. Scattered, unsealed cracks were observed and should be sealed prior to
overlaying. A minimum overlay thicknesses of 1½ inches is recommended to extend
the pavement design life to 20 years.
Existing Floor Slabs and Proposed Replacements: Subgrade soil conditions
appear to be adequate for slab support to meet the Retailer’s minimum requirement of
150 pci for the composite subgrade modulus. The existing slab also meets the
Retailer’s minimum requirements for 4-inch thick concrete slabs, and appears to be
reinforced with No. 4 rebar. Recommendations for preparation of slab replacement
area subgrades are included in this report.
Foundation Recommendations: New, lightly loaded, foundations for freezer slabs
and screen walls are planned. New foundations for lightly loaded structures may be
supported on two feet of structural fill placed over firm native subgrade soils for the
bearing pressures provided in this report.
This summary should be used in conjunction with the entire report for design purposes. It
should be recognized that details were not included or fully developed in this section, and the
report must be read in its entirety for a comprehensive understanding of the items contained
herein. The GENERAL COMMENTS section should be read for an understanding of the report
limitation.
Page 1
FINAL GEOTECHNICAL ENGINEERING REPORT
PROPOSED WALMART NEIGHBORHOOD MARKET #5995-00
17711 JEAN WAY
LAKE OSWEGO, OREGON
Project No. 82105050
March 16, 2012
1.0 INTRODUCTION
In accordance with your request and written authorization, Terracon has completed a
geotechnical engineering evaluation for the proposed Walmart Neighborhood Market project in
Lake Oswego, Oregon. Terracon completed the on-site evaluation in November 2010. This
evaluation served as the basis for providing geotechnical engineering conclusions and
recommendations regarding:
Existing pavement and subgrade conditions,
New pavement and overlay design and construction,
Existing floor slab thickness, slab subgrade conditions and replacement
recommendations, and
Footing recommendations for lightly-loaded tenant improvements.
The site and exploration plan, logs of the explorations, and the pavement condition observations
plan completed for the project are presented in Appendix A. The results of the laboratory testing
performed on select soil samples are included in Appendix B of this report. Soil classification
information sheets are included in Appendix C. Project Figures and Supporting Documents are
provided in Appendices D and E, respectively. Descriptions of the field exploration and laboratory
testing procedures are included in their respective appendices.
2.0 PURPOSE AND SCOPE
The purpose of the geotechnical engineering evaluation was to characterize the site’s parking
lot subsurface conditions in accordance with the Retailer’s September 22, 2011 Geotechnical
Investigation Specifications and Report Requirements, as well as determine the interior slab-on-
grade floor thickness and slab subgrade conditions at locations selected by the architect. Our
scope of services included a surface reconnaissance, subsurface boring explorations, crack
mapping of the existing pavement, laboratory testing, geotechnical engineering analysis, and
preparation of this report. Our geotechnical scope of services did not include quantitative or
qualitative characterization of regulated environmental contaminants. However, a draft Phase I
Environmental Site Assessment (ESA) is being concurrently performed by Terracon and will be
submitted to PACLAND under separate cover. No efficiencies were realized from possibly
combining a Phase II ESA due to the timing difference between these efforts.
Final Geotechnical Engineering Report Proposed Neighborhood Market #5995-00 ■ Lake Oswego, Oregon March 16, 2012 ■ Terracon Project No. 82105050
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3.0 PROJECT INFORMATION
3.1 Site Location
ITEM DESCRIPTION
Location The site is located at 17711 Jean Way, Lake Oswego, Oregon.
Existing improvements
The site is currently developed with an existing retail building
(approximately 34,000 square feet) and associated asphalt paved
parking areas, drive lanes, and truck loading docks, as shown on
Exhibit A-1.
Current ground cover
The majority of the site is asphaltic concrete pavement with
portland cement concrete sidewalks and landscape islands
scattered throughout the site.
Existing topography
The site and vicinity are relatively flat with a slight slope
(approximately 5 percent) from the building pad to the east edge of
the parking lot. An approximate 5-foot deep stormwater pond is
located on the northern end of the site.
3.2 Project Description
ITEM DESCRIPTION
Improvements
The project will include a tenant takeover of the former grocery
store space of approximately 34,000 square feet with associated
tenant improvements, including large areas of floor slab
replacement. Asphaltic concrete pavement overlay of the main
auto parking, heavy duty truck lanes, and loading dock ramp are
planned.
Foundations New freezer footings.
Grading
Fill: None anticipated.
Excavation Cuts: None anticipated.
A full pavement overlay will be completed as part of this project.
Cut and fill slopes None anticipated.
Retaining walls None anticipated.
4.0 SITE CONDITIONS
We performed a visual reconnaissance of the site to assess the existing pavement conditions
and slab conditions from a geotechnical standpoint. A detailed description of the pavement
conditions is included in the Pavements section of this report and is shown in Exhibit A-2.
Final Geotechnical Engineering Report Proposed Neighborhood Market #5995-00 ■ Lake Oswego, Oregon March 16, 2012 ■ Terracon Project No. 82105050
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We performed two cores inside the building at approximate locations requested by the architect.
Core C-1 was located in the sales area near the main entrance, and core C-2 was located in the
loading dock area. The core and hand boring data is presented in Section 5.1 of this report and
logs are included in Appendix A. As shown on the core logs, the thickness of the slab ranged
from 5 to 5½ inches.
The floor finish appeared to be a combination of stained and unfinished concrete with scattered
architectural designs, but no flooring tiles or covers. Scattered areas of typical minor slab
cracking were observed, but no obvious indications of settlement issues, such as down set
construction joints, depressions, or tilted slab panels. Areas of moisture intrusion, such as
efflorescence, were not observed in the slab areas.
Minor to moderate cracking was observed in the portland cement concrete sidewalk panels in
front of the store. The largest cracked areas were in front of the main store entrance. However,
no excessive settlements were observed in the cracked panels.
5.0 SUBSURFACE CONDITIONS
5.1 Published Geologic Literature
The Geologic map of the Lake Oswego Quadrangle, Clackamas, Multnomah, and Washington
Counties, Oregon (GMS-59)1 indicates that near-surface deposits at the site are channel facies
(Qfch) deposited in the Pleistocene epoch over 12,000 years ago. This unit is described as
sediments that are complexly interlayered and variable silts, sands, and gravels, deposited in
major floodways. The channels are cut in earlier and/or contemporaneous fine and coarse flood
sediments (Qff and Qfc). The irregular post-flood surfaces of these deposits have been locally
filled by bog or pond sediments and by overbank alluvium from local creeks.
The United States Department of Agriculture Soil Conservation Service has published a series
of soil surveys with typical soil properties located within each county of Oregon. Below is a
table summary of relevant information within the online survey data for the upper 10 feet:
Soil Type USCS
Classification Liquid Limits
Plasticity Index
Corrosion of Concrete
Corrosion of Steel
pH Hydrologic
Group
Salem silt loam CL 21 5 Moderate Moderate 6.4 B
1 Beeson, M.H., Tolan, T.L. and Madin, I.P., 1989, Geologic map of the Lake Oswego quadrangle, Clackamas,
Multnomah, and Washington Counties: Oregon Department of Geology and Mineral Industries, Geological Map
Series 59, scale 1:24000.
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5.2 Subsurface Explorations
The subsurface conditions for the subject site were evaluated during our field exploration
program during November and December 2010. Soil descriptions presented in this report are
based on the subsurface conditions encountered at specific exploration locations across the site
at the time the explorations were performed. The subsurface conditions encountered are
summarized below while the interpretive logs of the explorations are presented in Appendix A.
The approximate exploration locations are presented on the Site and Exploration Plan (Figure
A-1). Descriptions of the field procedures and equipment used are presented in Appendix A
along with the horizontal coordinates and ground surface elevations of the borings.
5.3 Generalized Subsurface Profile
Specific conditions encountered at each exploration location are indicated on the individual
exploration logs. Stratification boundaries on the exploration logs represent the approximate
location of changes in soil types; in-situ, the transition between materials may be gradual. Details
for each of the explorations can be found on the exploration logs included in Appendix A of this
report. Based on the results of the explorations, subsurface conditions on the project site can be
generalized as follows:
Final Geotechnical Engineering Report Proposed Neighborhood Market #5995-00 ■ Lake Oswego, Oregon March 16, 2012 ■ Terracon Project No. 82105050
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Generalized Subsurface Profile of Borings P-1 to P-7
Description
Approximate Depth to
Bottom of Stratum
(feet)
Material Encountered Consistency/Density
Pavement 2½ to 4 inches Asphaltic Concrete -
Base Course 8 to 20 inches Crushed rock (Medium dense)
Fill 2½ to 4½ Gravel with sand, trace silt;
Silt with sand, trace gravel
Very loose to very
dense;
Very stiff
Silt 2½ to 7½ Silt with fine sand Stiff to very stiff
Gravel 4 to 10½+ Gravel with sand, trace silt Medium dense to very
dense
Basalt Boulders 10 to 12+
Slightly vesicular, slightly
weathered, close joints,
interbedded with gravels/sands
Hard
Anecdotal evidence from local constructors indicates that the site and vicinity contains
numerous large boulders. Several large basalt boulder were observed in the landscaping areas
that were similar to the rock core samples and should be expected in excavations throughout
the site.
During our first drilling attempt on November 12, 2010, we encountered auger refusal with a
trailer-mounted drill using solid stem augers. We notified PACLAND at that time, and
remobilized on November 18, 2010 with a truck-mounted Mobile B-60 with hollow-stem auger
and rock coring capabilities. Even with the B-60, auger refusal was encountered in borings P-1,
P-2, P-3, P-4, and P-6 at depths of approximately 4 feet, 5½ feet, 5¼ feet, 8 feet, and 6½ feet,
respectively. We interpret these refusals to be in the basalt boulders. The overlapping of the
basalt and gravel/sand sediments is interpreted to be from suspected deposition of boulders in a
coarse alluvial matrix. Based on the very poor to poor Rock Quality Designator (RQD) values
ranging from 14 to 25 percent, the rock should be rippable with large excavator-mounted
jackhammers if encountered in utility trenches.
Slab and Slab Subgrade Conditions in Cores C-1 and C-2
Core No. Concrete Slab Thickness (in)
Vapor Retarder
Curing Sand Thickness* (in)
Base Thickness
(in) Subgrade Soil
C-1 5½ (concrete) black
visqueen 2 16 Silty SAND with gravel
C-2 5 (concrete) black
visqueen 2 15 Silty SAND with gravel
1 Two inches of sand were encountered between the slab and the vapor retarder and is interpreted to be curing
sand and not a capillary break material.
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Variations in subsurface conditions may exist between the exploration locations and the nature
and extent of variations between the explorations may not become evident until construction.
Stratification boundaries on the boring logs represent the approximate depth of changes in soil
types, although the transition between materials may have been gradual. If variations become
apparent during construction, it may be necessary to reevaluate the recommendations of this
report.
5.4 Groundwater
During our evaluation, which was completed in November 2010, we observed groundwater in
one of the seven borings performed for the geotechnical evaluation. Groundwater was
encountered in boring P-7 at one foot in depth and is interpreted to be perched groundwater
within the base course material. Due to the current use of the parking lot as unofficial commuter
parking, we chose not leave the borings open for 24-hour water level readings since barricading
these boring areas would block access to drive lanes and some parked cars. Groundwater
conditions, that include quantity and duration of flow, as well as soil moisture conditions, should
be expected to vary with changes in season, precipitation, site utilization, and other on- and off-
site factors not evident at the time the explorations were completed. In addition, perched
groundwater could develop within the pavement base course following periods of heavy or
prolonged precipitation.
5.5 Geologic Hazards
Seismic hazards resulting from earthquake motions can include slope instability, liquefaction,
and surface rupture due to faulting or lateral spreading. Liquefaction is the phenomenon
wherein soil strength is dramatically reduced when subjected to vibration or shaking.
We reviewed the Relative Earthquake-Hazard Maps of the Lake Oswego Quadrangle, Clackamas,
Multnomah, and Washington Counties, Oregon, (GMS-91) published by the Oregon Department
of Geology and Mineral Industries (DOGAMI). The hazard maps show the project site to be
located in an area that is mapped as: moderate relative hazard for ground motion amplification;
least relative hazard for liquefaction; least relative hazard for slope instability; and Zone C for
the second to lowest relative hazard for earthquakes based on all three hazards.
Liquefaction generally occurs in loose sand or non-plastic silt deposits that are below the water
table. Based on the above published geologic information and the subsurface conditions
encountered in the borings, it is our opinion that the risk of liquefaction is low for the site.
Therefore, liquefaction-induced settlements are not expected.
We reviewed the USGS Earthquake Hazards Program Quaternary Faults and Folds Database available
online (http://earthquake.usgs.gov/regional/qfaults/usmap.php). The nearest fault to the project
Final Geotechnical Engineering Report Proposed Neighborhood Market #5995-00 ■ Lake Oswego, Oregon March 16, 2012 ■ Terracon Project No. 82105050
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site is the Canby-Molalla fault approximately one-half mile southwest of the project site.
According to this source, the fault age is in the less than 15,000 years category, has been
mapped with north-northwest striking features, and is in the slip rate category of less than 0.2
mm/year. Based on the information described above, we estimate that the risk associated with
surface rupture at the site is low to moderate.
6.0 CLIMATE DATA
Based on the local weather conditions described in the Climatic Atlas of the United States
published by the U.S. Department of Commerce and the Western Regional Climate Center, wet
weather conditions at this site could be anticipated between about October through April.
Weather data from the Western Region Climate Center (WRCC) states that the average annual
precipitation in the region is approximately 46.2 in., with an average of approximately 1.58
inches of precipitation, during the period from May through September. During winter months of
November to March, the average monthly minimum and maximum temperatures range from
about 35.2 to 39.8 degrees Fahrenheit (F) and 46.9 to 56.7 degrees F, respectively. Average
annual snowfall is about 4.4 inches.
The average total precipitation for each month at the WRCC Oregon City, Oregon station
(weather station No. 356334) is as follows:
January: 7.16 in. July: 0.64 in.
February: 5.06 in. August: 1.02 in.
March: 4.91 in. September: 1.94 in.
April: 3.32 in. October: 3.63 in.
May: 2.48 in. November: 6.78 in.
June: 1.83 in. December: 7.40 in.
Total Average Annual Precipitation 46.18 in.
The WRCC Monthly Climate Summary data for the referenced station is attached in Appendix
E.
7.0 LABORATORY TESTING
Samples retrieved during the field exploration programs were returned to the laboratory for
observation by the project geotechnical engineer and were visually or manually classified in
general accordance with the Unified Soil Classification System described in Appendix C. At
that time, the field descriptions were confirmed or modified as necessary and an applicable
laboratory testing program was formulated to determine engineering and index properties of the
subsurface materials. Exploration boring logs were prepared and are presented in Appendix A.
Final Geotechnical Engineering Report Proposed Neighborhood Market #5995-00 ■ Lake Oswego, Oregon March 16, 2012 ■ Terracon Project No. 82105050
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Laboratory tests were conducted on selected soil samples and are presented on the exploration
logs and in Appendix B. The test results were used for the geotechnical engineering analyses,
and the development of foundation and earthwork recommendations. Laboratory tests were
performed in general accordance with the applicable local standards or other accepted
standards. Selected soil samples were tested for one or more of the following index and
engineering properties:
Moisture Content California Bearing Ratio
Grain Size Distribution Resistivity and pH
Atterberg Limits
Standard Proctor
Organic Matter Content
7.1 Topsoil Testing
A total of seven borings were completed during our site investigation and topsoil was not
encountered in any of these explorations. Therefore, no topsoil samples were submitted for
topsoil testing.
7.2 Soil Corrosion Potential
Results of the pH and resistivity testing are presented below in the following table:
Boring Number Depth (ft) pH Resistivity (ohm-cm)
C-1 2 7.60 2,700
C-2 2¼ 6.85 3,400
P-6 1 - 2½ 7.42 3,400
ND = Not detected above the method reporting limit.
The electrical resistivity of each sample listed above was measured in the laboratory with
distilled water added to create a standardized condition of saturation. Resistivities are at about
their lowest value when the soil is saturated. Electrical resistivities of soils are a measure of their
resistance to the flow of corrosion currents. Corrosion currents tend to be lower in high
resistivity soils. The electrical resistivity of the soils varies primarily with its chemical and
moisture contents. Typically, the lower the resistivity of native soils, the more likely that galvanic
currents may develop and increase the possibility of corrosion.
Based on laboratory test results, resistivity values for the near surface native soils ranged from
2,700 to 3,400 ohm-cm. Soils with resistivity values below 2,000 ohm-cm are generally
associated with soils classified as “very to severely corrosive” towards buried metal objects
Final Geotechnical Engineering Report Proposed Neighborhood Market #5995-00 ■ Lake Oswego, Oregon March 16, 2012 ■ Terracon Project No. 82105050
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while soils with resistivity values between 2,000 and 5,000 ohm-cm are generally associated
with soils classified as “corrosive”. Soils with resistivity values between 5,000 and 10,000 ohm-
cm are generally associated with soils classified as “moderately corrosive”. The pH levels are
considered to be essentially neutral and are generally associated with low corrosion rates in
carbon steel. It is our opinion that Type I or Type II cement is suitable for this project.
Based on the resistivity values, the existing fill soils would be generally classified as “corrosive”
towards buried metals. Therefore, we recommend the use of PVC pipes instead of metallic
pipes where applicable. If metal pipes are used, we recommend that ductile iron pipes be
polyethylene encased and corrugated metal pipes be galvanized, aluminized or polymer coated,
at a minimum. The manufacturers of specific products should be contacted for additional or
alternative corrosion protection recommendations.
8.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION
8.1 Geotechnical Considerations
The primary geotechnical considerations for this project include:
Pavements: The parking lot pavement appears to be the original, approximately 13-
year-old pavement in fair condition. Scattered, unsealed cracks were observed and
should be sealed prior to overlaying. The Retailer’s minimum overlay thicknesses may
be performed due to the fair condition of the existing pavement and fair subgrade
support.
Existing Floor Slabs and Proposed Replacements: Subgrade soil conditions
appear to be adequate for slab support to meet the Retailer’s minimum requirement of
150 pci for the composite subgrade modulus. The existing slab also meets the
Retailer’s minimum requirements for 4-inch thick concrete slabs, and appears to be
reinforced with No. 4 rebar. Recommendations for design and construction of new
floor slab replacement areas are provided below.
Foundation Recommendations: New, lightly loaded, foundations for freezer slabs
and screen walls are planned. New foundations for lightly loaded structures may be
supported on two feet of structural fill placed over firm native subgrade soils for the
bearing pressures provided in this report.
Geotechnical engineering recommendations for pavements and other earth related phases of
the project are outlined below. The recommendations contained in this report are based upon
Final Geotechnical Engineering Report Proposed Neighborhood Market #5995-00 ■ Lake Oswego, Oregon March 16, 2012 ■ Terracon Project No. 82105050
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the results of field and laboratory testing (which are presented in Appendices A and B),
engineering analyses, and our current understanding of the proposed project.
8.2 Earthwork
Earthwork for the project is anticipated to be limited to utility trench work or minor site work. The
following presents recommendations for site preparation, excavation, subgrade preparation and
placement of engineered fills on the project. The recommendations presented for design and
construction of pavements are contingent upon following the recommendations outlined in this
section.
Earthwork on the project should be monitored and evaluated by a qualified geotechnical
engineering company. The evaluation of earthwork should include observation and testing of
engineered fill, subgrade preparation, and other geotechnical conditions exposed during the
construction of the project.
8.2.1 Site Preparation
Site Drainage: Some earthwork aspects of the project could be impacted by the moisture-
sensitive nature of the on-site soils. Excavation, grading, and subgrade preparation should be
performed in a manner and sequence that will provide drainage and control of stormwater runoff
and erosion at all times in accordance with the project plans and local requirements. If
prolonged or substantial precipitation is anticipated, the site should be graded to prevent water
from ponding in construction areas and/or flowing into excavations. Exposed grades should be
crowned, sloped, and smooth-drum rolled at the end of each day to facilitate drainage if
inclement weather is forecasted. Accumulated water should be removed from subgrades and
work areas immediately and prior to performing further work in the area. Loose, disturbed soils
and soils subjected to repeated construction traffic that are exposed to wet weather or elevated
in moisture will quickly be reduced to mud. Equipment access may be limited and the amount
of soil rendered unfit for use as structural fill may be greatly increased if drainage efforts are not
accomplished in a timely manner.
Runoff from the existing asphalt paved areas should not be allowed to flow into excavation
areas. We recommend that asphalt berms or sandbags be used to divert runoff around the
excavation areas to a suitable discharge location.
Dewatering: Scattered areas of localized perched groundwater zones may be encountered in
excavations. Perched groundwater zones are often found in near surface soils and due to
infiltration of surface water in pavement cracks, and will likely be able to be pumped out of
sumps within excavations. The contractor should be prepared to control these areas of
localized groundwater seepage in the excavations.
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On-Site Soil Considerations - Wet Soil Conditions: Particle size analyses completed for this
study indicate that the subgrade soils contain very high percentages of fine-grained material
(i.e., silt and clay). In general, on-site soils are considered to be moisture sensitive and will be
difficult or impossible to compact as structural fill if they are over-optimum by 2 percent or more.
Accordingly, the ability to use native soils from site excavations as structural fill will depend on
their moisture content at the time of earthwork and the prevailing weather conditions when site
grading activities take place.
At the time of our study, moisture contents of the surface and near-surface soils ranged from
near-optimum moisture content to as much as 6 percentage points above optimum. A Standard
Proctor test completed on a composite sample of the near-surface silt soils had an optimum
moisture content of 13.5 percent. It is likely that over-optimum soils will be encountered during
construction and in order to use soils that are wet of the optimum moisture content, the soils will
need to be dried by aeration during dry weather conditions, or an additive, such as cement kiln
dust, may be needed to stabilize the soil.
In our opinion, earthwork should be completed during periods of the year when the moisture
content can be controlled by aeration and drying. If earthwork or construction activities take
place during extended periods of wet weather, or if the in-situ moisture conditions are elevated
above the optimum moisture content, the soils could become unstable or not be compactable.
In the event the exposed subgrade becomes unstable, yielding, or unable to be compacted due
to high moisture conditions, we recommend that the materials be removed to a sufficient depth
in order to develop stable subgrade soils that can be compacted to the minimum recommended
levels. Successful drainage of wet to saturated soils would be relatively slow due to the fines
content of the materials. The severity of construction problems will be dependent, in part, on
the precautions that are taken by the contractor to protect the subgrade soils.
8.2.2 Subgrade Preparation
Site preparation and initial construction activities should be planned to reduce disturbance to the
existing ground surface. Construction traffic should be restricted to dedicated driveway and
laydown areas if subgrade soil moisture conditions are elevated which could lead to
disturbance.
After cutting to design subgrade elevation where required by the grading/pavement plan, and
prior to placement of new fill in areas below finish grade, we recommend that the exposed
subgrades be proofrolled with heavy rubber-tired construction equipment, such as a fully-loaded
tandem-axle dump truck, to detect soft and/or yielding soils. Unsuitable areas identified by
proof-rolling and/or hand-probing by the owner’s representative should be overexcavated and
replaced with structural fill. The exposed subgrade soils should be firm, unyielding, and
compacted to at least 95 percent of the maximum dry density as determined by the ASTM D
1557 Modified Proctor Compaction Test for granular soils and 98 percent of the maximum dry
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density as determined by the ASTM D 698 Standard Proctor Compaction Test for fine-grained
soils. In the event that compaction fails to meet the specified criteria, the upper 12 inches of
subgrade should be scarified and moisture conditioned, as necessary to obtain required
percentage of the maximum laboratory density. Those soils which are soft, yielding, or unable
to be compacted to the specified criteria should be overexcavated and replaced with satisfactory
fill material as defined in Specification Section 02300. Vibrating compactors (smooth-drum or
plate) should not be used on silt and clay soils. Instead, sheep-footed compactors should be
used for fine grained soils.
Based on the outcome of the proofrolling operations, some undercutting or subgrade
stabilization should be expected, even more so during wet periods of the year. Methods of
stabilization, which are outlined below, could include scarification and recompaction, removal of
unstable materials and replacement with granular fill (with or without geotextiles) and chemical
stabilization. The most suitable method of stabilization, if required, will be dependent upon
factors such as schedule, weather, and the size of area to be stabilized and the nature of the
instability. More detailed recommendations can be provided during construction, as the need
for subgrade stabilization occurs. Performing site grading operations during the warmer and
drier months would aid in reducing potential need for subgrade stabilization.
Scarification and Recompaction - It may be feasible to scarify, dry, and recompact the exposed
soils. The success of this procedure would depend primarily upon favorable weather and
sufficient time to dry the soils. Even with adequate time and weather, stable subgrades may not
be achievable if the thickness of the soft soil is greater than about 1 to 1½ feet.
Granular Fill - The use of crushed stone or gravel could be considered to improve subgrade
stability. Typical undercut depths could range from about ½ foot to 2 feet. The use of high
modulus geotextiles (i.e., engineering fabric, such as Mirafi HP370 or geogrid, such as Tensar
TX140 or BX1100) could also be considered after underground work such as utility construction
is completed. Equipment should not be operated above the fabric or geogrid until one full lift of
granular fill is placed above it. The maximum particle size of granular material placed over
geotextile fabric or geogrid should not exceed 1½ inches. Geotextiles can also be considered
for severe subgrade conditions during winter months. It should be expected that a minimum of
12 inches of granular fill will be required with any geotextile application. Refer to section 7.2.3
of this report for additional fill specifications.
Overexcavations should be backfilled with structural fill material placed and compacted in
accordance with the Structural Fill section of this report. Subgrade preparation and selection,
placement, and compaction of structural fill should be performed under engineering controlled
conditions in accordance with the project specifications.
Subgrade Protection: If site grading activities are performed during extended dry weather
periods, extensive subgrade protection measures may not be necessary (although care should
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be taken to prevent over-drying). However, it should be noted that wet weather and possible
near freezing conditions prevail from November through March which could delay earthwork if
soil moisture conditions become elevated above the optimum moisture content.
The exposed native and fill silt soils could be sensitive to construction traffic during prolonged
periods of wet weather. If it becomes necessary to protect the subgrade, we recommend that
dedicated haul roads and lay down areas should be constructed with 3- to 6-inch quarry spalls,
free-draining selected granular backfill, selected stone backfill, dense graded aggregate or
crushed recycled concrete of equivalent gradation. Selected granular backfill, selected stone
backfill and dense graded aggregate are defined by Section 00330.14, 00330.15 and 02630.10,
respectively, of the Oregon Department of Transportation (ODOT) 2008 Oregon Standard
Specifications for Construction (Vol. 2). If wet weather or wet subgrade conditions necessitate
protection, we recommend that the contractor be responsible for determining the minimum
thickness of the protective layer, based on the conditions at that time.
Frozen Subgrade Soils: If earthwork takes place during freezing conditions, all exposed
subgrades should be allowed to thaw and then be recompacted prior to placing subsequent lifts
of structural fill or foundation components. Alternatively, the frozen material could be stripped
from the subgrade to reveal unfrozen soil prior to placing subsequent lifts of fill. The frozen soil
should not be reused as structural fill until allowed to thaw and adjusted to the proper moisture
content, which may not be possible during winter months.
Geotechnical Monitoring: A qualified construction testing laboratory should be present during
site preparation operations to observe subgrade conditions, overexcavating and replacing soft
and/or loose soils, observe the proof rolling operations, and to verify that that the exposed
subgrade has been prepared in accordance with the Subgrade Preparation section of this
report.
8.2.3 Fill Materials and Placement
All fill materials should be inorganic soils (with less than 3 percent organics) free of vegetation,
debris, and rock fragments larger than six inches in size. Approved imported materials may be
used as fill material for the following:
general site grading
pavement areas
slab and foundation areas
utility backfill
Imported soils for use as fill material within the site should conform to the following
specifications:
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Fill Type 1 Specification Acceptable Location for Placement
Common
Fill
Oregon Standard Specification
00330.13 Selected General
Backfill with exception of PI ≤ 10
All locations across the site, except for building pad.
Minimum CBR of 10% when compacted in accordance
with the recommendations presented In the following
table. Only recommend during dry weather and/or dry
site conditions.
Select Fill
Oregon Standard Specification
00330.14 Selected Granular
Backfill with exception of no
more than 8% passing the No.
200 sieve by weight
All locations across the site. Minimum CBR of 20%
when compacted in accordance with the
recommendations presented in the following table.
Applicable for dry or wet weather conditions.
Crushed
Aggregate
Base
Course
(CAB)
Oregon Standard Specification
02630.10 Dense Graded
Aggregate (1”-0) with the
exception of less than 8 percent
passing the No. 200 sieve.
Finished base course materials for pavements and
floor slabs. Applicable for dry or wet weather
conditions.
1. Controlled, compacted fill should consist of approved materials that are free (free = less than 3% by weight) of
organic matter and debris (i.e. wood sticks greater than ½-inch in diameter). Frozen material should not be used,
and fill should not be placed on a frozen subgrade. A sample of each material type should be submitted to the
geotechnical engineer for evaluation.
If open-graded materials with large void spaces, such as quarry spalls, are used over the fine-
grained native soils, we recommend that the materials be placed over a geotextile fabric
separator to prevent fines migration as well as to stabilize the subgrade. The geotextile fabric
should be a free-draining woven product (Mirafi HP370 or equivalent).
The following compaction requirements are recommended for the prepared subgrade and
structural fill expected to be placed for this site:
Item Description
Fill Lift
Thickness
Common Fill, Select Fill, and CAB: 8 inches or less in loose thickness when
heavy, compaction equipment is used.
Compaction
Requirements 1
Within the Building Pad Limits and upper 2 feet of pavement subgrade: 95%
of the material’s modified Proctor maximum dry density (ASTM D1557) for
granular materials and 98% of the material’s standard Proctor maximum dry
density (ASTM D698) for fine-grained materials.
Outside Building Pad Limits, within pavement areas and greater than 2 feet
below subgrade: 92% of the material’s modified Proctor maximum dry density
(ASTM D1557) for granular materials and 95% of the material’s standard Proctor
maximum dry density (ASTM D698) for fine-grained materials.
All other areas: 90% of the material’s modified Proctor maximum dry density
(ASTM D1557) for granular materials and 92% of the material’s standard Proctor
maximum dry density (ASTM D698) for fine-grained materials.
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Item Description
Moisture Content
Granular materials: Within ±2 percent of optimum moisture content as
determined by ASTM D 1557.
Fine-grained materials: Within -1 to +3 percent of optimum moisture content as
determined by ASTM D698. 1. We recommend that engineered fill be tested for moisture content and compaction during placement. Should the
results of the in-place density tests indicate the specified moisture or compaction limits have not been met, the
area represented by the test should be reworked and retested as required until the specified moisture and
compaction requirements are achieved.
8.3 Temporary and Permanent Slopes
Temporary slope cuts will likely be limited to relatively shallow utility excavations. New
permanent slope fills or cuts are not anticipated for this project.
8.3.1 Safety
Construction site safety generally is the sole responsibility of the Contractor, who selects and
directs the means, methods, and sequencing of construction operations. Temporary excavation
slope stability is a function of many factors, including:
The presence and abundance of groundwater;
The type and density of the various soil strata;
The depth of cut;
Surcharge loadings adjacent to the excavation; and
The length of time the excavation remains open.
As the cut is deepened, or as the length of time an excavation is open, the likelihood of bank
failure increases; therefore, maintenance of safe slopes and worker safety should remain the
responsibility of the contractor, who is present at the site, able to observe changes in the soil
conditions, and monitor the performance of the excavation.
8.3.2 Temporary Cut Slope Inclinations
It is exceedingly difficult under the variable circumstances to pre-establish a safe and
“maintenance-free” temporary cut slope angle. Therefore, it should be the responsibility of the
contractor to maintain safe temporary slope configurations since the contractor is continuously
at the job site, able to observe the nature and condition of the cut slopes, and able to monitor
the subsurface materials and groundwater conditions encountered. Unsupported vertical slopes
or cuts deeper than 4 feet are not recommended if worker access is necessary. The cuts
should be adequately sloped, shored, or supported to prevent injury to personnel from local
sloughing and spalling. The excavation should conform to applicable Federal, State, and Local
regulations.
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According to Chapter 437 of the Oregon Administrative Rules (OAR), the contractor should
make determination of excavation side slopes based on classification of soils encountered at
the time of excavation. Temporary cuts may need to be constructed at flatter angles based upon
the soil moisture and groundwater conditions at the time of construction. Adjustments to the
slope angles should be determined by the contractor at that time.
8.4 Foundations
We recommend the proposed screen wall and freezer slab footings be supported by a shallow,
spread footing foundation system bearing on 2 feet of structural fill consisting of newly placed
Select Fill above subgrades prepared in accordance with the Subgrade Preparation section of
this report. Design recommendations for shallow foundations for the proposed structure are
presented in the following paragraphs.
8.4.1 Foundation Design Recommendations
Description Value
Net allowable bearing pressure 1
Minimum 2-foot thick zone of Select Fill 2,500 psf
Minimum dimensions 18 inches
Minimum embedment below finished grade for frost protection 2 18 inches
Approximate total static settlement 3 <¾ inch
Estimated differential settlement 3 <½ inch over 40 feet
Allowable passive pressure 4 250 psf/ft
Allowable coefficient of sliding friction 4
0.35
1. The recommended net allowable bearing pressure is the pressure in excess of the minimum surrounding
overburden pressure at the footing base elevation. Assumes any unsuitable fill or soft soils, if encountered,
will be undercut and replaced with structural fill.
2. And to reduce the effects of seasonal moisture variations in the subgrade soils. For perimeter footing and
footings beneath unheated areas.
3. The foundation settlement will depend upon the variations within the subsurface soil profile, the structural
loading conditions, the embedment depth of the footings, the thickness of compacted fill, and the quality of the
earthwork operations. The above settlement estimates have assumed that the maximum footing width is 7½
feet for column footings and 2½ feet for continuous footings.
4. The value presented is an equivalent fluid pressure. The sides of the excavation for the spread footing foundation
must be nearly vertical and the concrete should be placed neat against these vertical faces for the passive
earth pressure values to be valid. Passive resistance in the upper 12 inches of the soil profile should be
neglected. A minimum factor of safety of 1.5 is included in the above allowable values.
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The net allowable bearing pressures presented in the table above may be increased by one-
third to resist transient, dynamic loads such as wind or seismic forces. Please note that lateral
resistance to footings should be ignored in the upper 12 inches from finish grade.
8.4.2 Foundation Construction Considerations
The base of all foundation excavations should be free of water and loose soil and rock prior to
placing concrete. Concrete should be placed soon after excavating to reduce bearing soil
disturbance. Should the soils at bearing level become excessively dry, disturbed or saturated,
or frozen, the affected soil should be removed prior to placing concrete. Place a protective layer
of crushed rock over the bearing soils if the excavations must remain open over night or for an
extended period of time.
The foundation areas are planned to be
overexcavated 2 feet in depth below the
bottom of the proposed footing and the
excavation replaced with imported Select Fill;
if additional unsuitable bearing soils are
encountered in footing excavations, the
excavations should be extended deeper to
suitable soils and the footings could bear on
properly compacted backfill extending down to
the suitable soils. Overexcavation for
compacted backfill placement below footings
should extend laterally beyond all edges of the footings at least 8 inches per foot of
overexcavation depth below footing base elevation as shown on the adjacent figure. The
overexcavation should then be backfilled up to the footing base elevation with materials
described in the Fill Materials and Placement section of this report.
Where the new footings tie into the
existing building footings, the planned
2-foot deep overexcavation should be
stepped down from the existing edge
of footing at a 1H:1V inclination to
avoid disturbing the bearing soils of
the existing foundation as shown in the
figure below. The overexcavation
should be backfilled immediately to
preserve the integrity of the existing
bearing soils. Under no circumstances
should the overexcavation adjacent
existing footings be allowed to remain
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exposed overnight. The stepped excavation is shown in the above figure.
Final exterior grades should promote free and positive drainage from the building areas at all
times. Water must not be allowed to pond or to collect adjacent to foundations or within the
immediate building area. We recommend that a gradient of at least 3 percent for a minimum
distance of 10 feet from the building perimeter be provided, except in paved locations. In paved
areas, a minimum gradient of one percent should be provided. In our opinion, perimeter footing
drains are not necessary for the screen wall footings. However, footing drains are
recommended for building perimeter walls, retaining walls, and loading dock walls.
8.5 Floor Slab
8.5.1 Floor Slab Design Recommendations
Description Value
Interior floor system Concrete slab-on-grade.
Base / Capillary Break 15 inches of Crushed Aggregate Base Course (also capillary
break material)
Subbase
None, other than compact upper 1 foot of existing subgrade soils
or utility backfill soils to a firm and unyielding condition of at least
92 percent of modified Proctor maximum dry density (ASTM D
1557) for granular soils or 95 percent of Standard proctor
maximum dry density (ASTM D 698) for fine-grained soils.
Modulus of subgrade reaction 200 pci for point load conditions.
1. Floor slabs should be structurally independent of any building footings or walls to reduce the
possibility of floor slab cracking caused by differential movements between the slab and
foundation.
From a geotechnical standpoint, the use of a vapor retarder beneath the interior slabs is not
considered necessary. However, we anticipate that some moisture will develop beneath the slab
as a result vapor migration through the soil. We recommend that the floor slab designer
determine if the moisture collection beneath the slab will adversely affect the performance of the
floor and the various floor coverings that may be placed on the floors. If a vapor barrier is to be
used, we recommend using a puncture-resistant product that is classified as a Class A vapor
retarder in accordance with ASTM E 1745. To avoid puncturing of the vapor retarder,
construction equipment should not be allowed to drive over any vapor retarder material. The
slab designer and slab contractor should refer to ACI 302 and/or ACI 360 for procedures and
cautions regarding the use and placement of a vapor retarder. The existing curing sand layer
may be deleted on replacement areas.
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8.5.2 Floor Slab Construction Considerations
For takeover projects, we anticipate that most floor slab installations will consist of replacement
slabs in select areas of the store for installation of insulation and utilities under freezer areas and
other utility installations. When making sawcuts for the floor replacement areas, we recommend
that the sawcut be located at least 6 inches wider than the anticipated excavation through the
existing slab base course material. This extra width outside the excavation limits will help reduce
the potential raveling of the base course materials into the excavation, which will help prevent
undermining and loss of support of the adjacent slab areas to remain.
8.6 Utility Trenching and Backfilling
8.6.1 Utility Trenching
We recommend that utility trenching, installation, and backfilling conform to all applicable
Federal, State, and local regulations such as OR-OSHA and OSHA regulations for open
excavations. Some excavation bank stability problems for utility construction may occur where
excavations extend into native soils or soils with elevated moisture conditions.
Where water is encountered in excavations, it should be removed prior to fill placement. If
dewatering becomes necessary, it should be designed and maintained by the contractor.
Depending on the season of the work, groundwater seepage elevations may be higher than that
encountered in our borings. It is possible that pumped sumps may be necessary for
excavations that penetrate into perched groundwater zones.
8.6.2 Utility Subgrade Preparation
We recommend that all utility subgrades be firm and unyielding and free of all soils that are
loose, disturbed, or pumping. Such soils should be removed and replaced, if necessary. All
structural fill used to replace overexcavated soils should be compacted as recommended in the
structural fill section of this report. If utility foundation soils are soft, we recommend that they be
overexcavated and replaced with structural fill. The necessary depth of excavation would need
to be determined in the field by a qualified geotechnical engineer.
Structures such as manholes and catch basins which extend into soft soils should be underlain
by at least 12 inches of crushed gravel fill compacted to at least 95 percent of the modified
Proctor maximum dry density. This granular material could consist of crushed rock, quarry
spalls, or coarse crushed concrete. Alternatively, quarry spalls or pea gravel could be used until
above the water level. It may be necessary to place a geotextile fabric over the native subgrade
soils if they are too soft, to provide a separation between the bedding and subgrade soils.
8.6.3 Pipe Bedding
We recommend that pipe zone material conform to material specifications as presented in
Section 00405.13, Pipe Zone Material, of the Oregon Standard Specifications. A minimum of 4
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inches of bedding material be placed in the trench bottom for flexible pipes. Bedding material
should conform to material as defined in Section 00405.12, Bedding, of the 2008 Oregon
Standard Specifications. All trenches should be wide enough to allow for compaction around
the haunches of the pipe.
8.6.4 Trench Backfill
The native soils may not be suitable for utility trench backfill due to the elevated moisture
content, depending on the time of the year and moisture conditions encountered. All trench
backfill should be placed as structural fill and compacted to the levels recommended within this
report. All trenches should be wide enough to allow for compaction around the haunches of the
pipe.
8.7 Pavements
We understand the truck route planned for the store will have a heavy duty overlay, and the
remaining areas will be overlain with a standard-duty section asphalt pavement overlay. The
recommended pavement sections and overlays are shown in Figures D-2 and D-3.
8.7.1 Existing Pavement Conditions
Existing pavement section thicknesses as encountered in our explorations are summarized in
the table below. We understand the development is approximately 13 years old and appears to
consist of the original pavement surfacing since the asphalt cores obtained during drilling did not
appear to contain an overlay. A plan showing our observations of the pavement conditions (i.e.,
cracks, patches) is shown in Exhibit A-2. No areas of alligatoring were observed at the time of
our visit. An approximately 3-foot by 3-foot square area around boring P-3 was cold patched by
Terracon after repairing a power and sump monitoring conduit in the boring.
Boring No. Asphaltic Concrete
Thickness (in) Base Course
Thickness (in)
P-1 3¼ 12
P-2 3¼ 8
P-3 4 9
P-4 3½ 9
P-5 2½ 8
P-6 3¾ 8
P-7 4 20
8.7.2 Pavement Repair/Preparation
Since the existing pavement is 13 years old and likely designed for a 20-year design life, we
anticipate that the pavement has approximately 7 years of service life left, if routine
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maintenance is performed. Even during this period, continued degradation of the asphalt and
more frequent sealing and patching should be expected. Furthermore, additional asphalt
concrete thickness is need in the south entrance drive lane near boring P-1 to meet the Retailer
minimum of 4 inches for heavy duty areas. Therefore, in order to re-establish a 20-year design
life, we recommend that asphalt overlays be constructed with the minimum thicknesses as
shown in the table below.
Areas of alligator cracking, if any are observed at the time of construction, indicate subgrade
failure and should be completely removed, the subgrade repaired, and the pavement replaced
with the recommended thicknesses for new pavement provided in the following section. Without
proper crack repairs, reflective cracking in the overlay should be anticipated. Furthermore, the
contractor should identify the cold patch area around boring P-3 and repair it with additional
base course and hot mix asphalt during construction since it is in the heavy duty drive lane.
Traffic Area Recommended Asphalt Overlay Section Thickness (inches)
Asphalt Concrete Overlay
Standard Duty 1.5
Heavy Duty 1.5
The primary goal of patching linear cracks or removing severely alligator areas is to reduce the
risk of reflection cracks and the associated degradation of the new overlay. The basic
mechanism of reflection cracking is strain concentration in the overlay due to movement in the
area of cracks in the original pavement. This movement may be bending or shear induced by
loads or contraction created by temperature changes. Pre-overlay repair may help delay the
occurrence of reflection cracks. Paving fabrics may also help to control reflection cracking.
Reflection cracks have a considerable influence on the life of an overlay. They require frequent
maintenance such as sealing and patching. Reflection cracks allow water to enter the pavement
structure that may result in a loss of bond between the layers of asphalt.
Alligator Cracks: Alligator cracks are usually associated with granular base that has
failed or soft subgrades, or inadequate pavement surfacing strength or thickness.
Severe alligator cracking requires removal of the distressed area, patching, and a
structural overlay to prevent this distress from reoccurring. Areas of alligator cracking
were not observed as of December 2010. However, areas of alligator cracking may be
present at the time of construction due to continued use of the site for unofficial
commuter parking and should be field verified by the contractor prior to bidding. Areas
of observed alligator cracking should be completely removed, the subgrade repaired,
and replaced with the recommended sections for new pavement.
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Linear Cracks: Cracks in traffic lanes that are parallel to the flow of traffic are referred to
as longitudinal cracks. Those that are perpendicular to the flow of traffic are referred to
as transverse cracks. Longitudinal cracking were observed within most drive lanes, with
occasional transverse cracks. Linear cracks are sometimes created by settling utility
trench backfill, the location of construction joints, or possibly soft subgrades. For severe
linear cracks that are open more than about ¼ inch, we recommend that they be filled
with a sand-asphalt mixture or other suitable crack filler. We recommend cracks less
than ¼ inch wide be sealed with hot poured asphalt. A paving fabric should be placed
over all filled linear cracks and cracks less than ¼ inch to control reflective cracking.
We recommend that the existing pavement surface to be overlayed be thoroughly
cleaned and the cracks pressure washed to remove debris. After drying, the cracks
should be sealed with emulsified or cut-back asphalt. Immediately after, the cracks
should be overlain with a paving fabric such as Amoco Petromat®, Tensar Glasgrid®,
Trumbull TruPave®, or an approved equivalent. We recommend that the cracks be
covered with minimum 1-foot wide strips of the fabric or the minimum recommended by
the manufacturer, whichever is greatest. In general, the fabric should be installed in
accordance with the manufacturer guidelines.
We recommend that existing asphalt surface be prepared in accordance with Oregon
State Department of Transportation (ODOT) Standard Specifications 00350.41(f)
Pavement Overlay Geotextile, 00610 Reconditioning Existing Roadway, and 00746
Crack Sealing Flexible Pavements. Prior to placing the overlay, an emulsified asphalt
tack coat should be applied to the existing asphalt in accordance with Oregon Standard
Specification 00730.
8.7.3 Design Recommendations
Design of new pavements for the project has been based on the procedures outlined in the
1993 Guideline for Design of Pavement Structures by the American Association of State
Highway and Transportation Officials (AASHTO).
Soil Design Values: The subgrade soils are anticipated to consist of firmly compacted granular
base course and/or structural fill material overlying native silt and clay soils. Terracon
completed one California Bearing Ratio (CBR) test on a representative native soil sample and a
CBR value of about 10 percent was obtained at 95 percent relative compaction of the Standard
Proctor value obtained. We recommend that all proposed fill soils used to establish pavement
subgrades have pavement support characteristics that are equivalent to (or better) that the
material used to develop our pavement design recommendations.
Traffic Design Values: Traffic loading provided for heavy-duty pavements consists of 211,700
18-kip ESALs over 20 years and 109,500 18-kip ESALs for standard-duty pavements. Other
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design parameters used in the design included initial serviceability = 4.2, terminal serviceability
= 2.0, reliability = 85%, and standard deviation = 0.45 for flexible pavements and 0.35 for rigid
pavements.
Recommended new flexible and rigid pavement sections, summarized for each traffic area, are
as follows:
Traffic Area
Recommended New Asphalt Pavement Section Thickness (inches)
Asphalt
Concrete
Surface
Aggregate
Base
Course
Gravel
Borrow
Subbase
Total
Standard Duty 3.0 6.0 - 9.0
Heavy Duty 4.0 6.0 - 10.0
Traffic Area
Recommended New Concrete Pavement Section Thickness (inches)
Portland Cement
Concrete Surface
Aggregate
Base Course
Gravel Borrow
Subbase Total
Standard Duty 5.0 4.0 - 9.0
Heavy Duty 6.0 4.0 - 10.0
Truck Loading
Dock/Dumpster Pad 7.0 4.0 - 11.0
The recommended pavement sections and pavement design calculations are provided in
Appendix D and E, respectively. Re-evaluation of the recommended pavement sections may be
necessary if the actual traffic varies from the assumed criteria outlined above.
The asphalt pavement sections recommended in the table above are not intended for
construction traffic. If the pavements will be constructed early during the construction
sequence, such that they will be subjected to construction traffic, provisions should be made for
completing repairs to the roadway and placing a new wearing surface near the end of
construction.
As previously stated, haul roads and laydown areas should be included in project planning to
provide access to the building area during construction.
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8.7.4 Asphalt and Base Course Materials
Specifications for manufacturing and placement of pavements and crushed base course should
conform to specifications presented in Section 00745, of the 2008 Oregon State Department of
Transportation, Standard Specifications for Construction. Specific recommendations for asphalt
concrete and crushed aggregate base course (CAB) are provided below.
Asphalt Concrete: We recommend that the asphalt cement binder conform to Oregon
Standard Specification Section 745.11 for PG 64-22, Performance Graded Asphalt. We
also recommend using a mix with aggregate meeting the gradation requirements for ½-
inch Dense as presented in Section 745.12, Broadband Limits for Dense Graded Mixes.
The job mix formula should meet the requirements for Level 2 dense graded mixtures for
standard duty traffic areas and Level 3 dense graded mixtures for heavy duty traffic
areas as presented in Section 745.13 of the Oregon Standard Specifications.
Crushed Aggregate Base: We recommend that the crushed aggregate base course
conform to gradation specifications presented in Section 02630.10, Dense Graded
Aggregate, grading 1”-0 with the exception of less than 8 percent passing the No. 200
sieve by dry weight.
Based on our experience in the Portland metro-area, these materials are locally available and
should be cost effective pavement materials.
Compaction – Asphalt and Base Course: All subbase and base course materials should be
compacted to at least 95 percent of the maximum dry density determined in accordance with
ASTM D 1557. We recommend that all base course be proofrolled with a loaded dump truck
prior to placing the following lift of material. We recommend that asphalt be compacted to a
minimum of 92 percent of the Rice (theoretical maximum) density.
8.7.5 Concrete Properties and Materials
Concrete pavement design recommendations are based on an assumed modulus of rupture of
580 psi and a minimum 28-day compressive strength of 4,000 psi for the concrete. It is our
opinion that concrete pavements should be reinforced and have relatively closely spaced control
joints on the order of 15 to 20 feet. We recommend that minimum reinforcement consist of 6x6-
W2.0xW2.0 welded wire or equivalent. The welded wire reinforcement should be terminated 3
inches on either side of all construction, contraction and expansion joints. We further
recommend that, at a minimum, loading dock pavements be reinforced with #3 bars on 15 inch
centers, each direction. We recommend that contraction joints be spaced no greater than 12
feet apart.
For areas subject to concentrated and repetitive loading conditions such as dumpster pads,
truck delivery docks and ingress/egress aprons, we recommend using a concrete pavement
Final Geotechnical Engineering Report Proposed Neighborhood Market #5995-00 ■ Lake Oswego, Oregon March 16, 2012 ■ Terracon Project No. 82105050
Responsive ■ Resourceful ■ Reliable Page 25
with a thickness of at least 7 inches underlain by at least 4 inches of crushed gravel. Prior to
placement of the crushed stone the areas should be thoroughly proofrolled. For dumpster pads,
the concrete pavement area should be large enough to support the container and tipping axle of
the refuse truck.
8.7.6 Construction Considerations
Materials and construction of pavements for the project should be in accordance with the
requirements and specifications of this report and the 2008 Oregon Standard Specifications for
Construction.
Preventative maintenance should be planned and provided for through an on-going pavement
management program in order to enhance future pavement performance. Preventative
maintenance activities are intended to slow the rate of pavement deterioration, and to preserve
the pavement investment.
Preventative maintenance consists of both localized maintenance (e.g. crack sealing and
patching) and global maintenance (e.g. surface sealing). Preventative maintenance is usually
the first priority when implementing a planned pavement maintenance program and provides the
highest return on investment for pavements.
9.0 GENERAL COMMENTS
Terracon should be retained to review the final design plans and specifications so comments
can be made regarding interpretation and implementation of our geotechnical recommendations
in the design and specifications. Terracon also should be retained to provide observation and
testing services during grading, excavation, foundation construction and other earth-related
construction phases of the project.
The analysis and recommendations presented in this report are based upon the data obtained
from the borings performed at the indicated locations and from other information discussed in
this report. This report does not reflect variations that may occur between borings, across the
site, or due to the modifying effects of construction or weather. The nature and extent of such
variations may not become evident until during or after construction. If variations appear, we
should be immediately notified so that further evaluation and supplemental recommendations
can be provided.
The scope of services for this project does not include either specifically or by implication any
environmental or biological (e.g., mold, fungi, bacteria) assessment of the site or identification or
prevention of pollutants, hazardous materials or conditions. If the owner is concerned about the
potential for such contamination or pollution, other studies should be undertaken.
Final Geotechnical Engineering Report Proposed Neighborhood Market #5995-00 ■ Lake Oswego, Oregon March 16, 2012 ■ Terracon Project No. 82105050
Responsive ■ Resourceful ■ Reliable Page 26
This report has been prepared in accordance with generally accepted geotechnical engineering
practices for the exclusive use of PACLAND, Wal-Mart Stores, Inc., and their respective
successors and assigns, for specific application to the project location and stated purpose. No
warranties, either express or implied, are intended or made. Site safety, excavation support,
and dewatering requirements are the responsibility of others. In the event that changes in the
nature, design, or location of the project as outlined in this report are planned, the conclusions
and recommendations contained in this report shall not be considered valid unless Terracon
reviews the changes and either verifies or modifies the conclusions of this report in writing.
Field Exploration Description FIELD EXPLORATION PROCEDURES AND LOGS Our subsurface exploration program for this project included the completion of seven borings performed in November 2010. The pavement borings were surveyed by a licensed land surveyor, in order to satisfy the Subsurface Investigation Specifications and Report Requirements for pavement borings only. As such, the exploration locations should be considered accurate to the degree implied by the measurement method. The approximate locations of the explorations are presented on Exhibit A-1, the Site and Exploration Plan. The following sections describe our procedures associated with the exploration. Descriptive logs of the explorations are enclosed in this appendix. Soil Boring Procedures Our exploratory borings were advanced using a truck-mounted drill rig operated by an independent drilling firm working under subcontract to our firm. The borings were completed using hollow-stem auger drilling methods. An engineer/geologist from our firm continuously observed the borings, logged the subsurface conditions encountered, and obtained representative soil samples. Samples were stored in moisture-tight containers and transported to our laboratory for further visual classification and testing. Throughout the drilling operation, soil samples were obtained at approximately 2.5-foot depth intervals by means of the Standard Penetration Test Method. This testing and sampling procedure consists of using a cathead hoist to drive a standard 2-inch outside diameter steel split spoon sampler 18 inches into the soil with a 140-pound hammer free falling 30 inches. The number of blows required to drive the sampler through each 6-inch interval is recorded, and the total number of blows struck during the final 12 inches is recorded as the Standard Penetration Resistance, or “blow count” (N value). If a total of 50 blows are struck within any 6-inch interval, the driving is stopped and the blow count is recorded as 50 blows for the actual penetration distance. The resulting Standard Penetration Resistance values indicate the relative density of granular soils and the relative consistency of cohesive soils. A conventional safety hammer was used to advance the split-barrel sampler in the borings performed on this site. Relatively intact samples were not obtained due to the generally gravelly nature of the soils. The enclosed boring logs describe the vertical sequence of soils and materials encountered in each boring, based primarily upon our field classifications and supported by our subsequent laboratory examination and testing. Where a soil contact was observed to be gradational, our logs indicate the average contact depth. Where a soil type changed between sample intervals, we inferred the contact depth. Our logs also graphically indicate the blow count, sample type, sample number, and approximate depth of each soil sample obtained from the boring, as well as any laboratory tests performed on these soil samples. Where groundwater was encountered in a borehole, the approximate groundwater depth, and date of observation, is depicted on the log. Groundwater depth estimates are typically based on the moisture content of soil samples, the wetted portion of the drilling rods, the water level measured in the borehole after the auger has been extracted, or through the use of an observation well. The soil descriptions presented on the boring logs in this appendix are based upon the drilling action, observation of the samples secured, laboratory test results, and field logs. The various types of soils are indicated as well as the depth where the soils or characteristics of the soils changed. It should be noted that these changes may have been gradual, and if the changes occurred between sample intervals, they were inferred.
Boring ID
Northing (ft) Easting (ft)NGVD29
Elev. (ft)
P‐1 638880.7 7627092.3 162.7
P‐2 638946.9 7627165.5 162.3
P‐3 639039.8 7627129.6 161.9
P‐4 639118.2 7627190.4 162.3
P‐5 639206.9 7627147.7 164.5
P‐6 639276.1 7627215.6 161.5
P‐7 639355.3 7627158.4 162.5
Note: These values should be considered accurate to the nearest +/- 1 foot in the horizontal directions and +/- ½ foot in elevation. Coordinates were collected and provided to Terracon by CESNW (clients surveyor).
SM
1
2
3
DCP = 22,30/ ½-inchDCP = 30/1¼-inches
DCP = 30/1½-inches
0.460.63
2
3
5½-inch Concrete slab with 2 #4 bar at3¾-inches below top of slabSAND, gray, moist,over black visqueen vapor retarderFILL: ¾-inch minus crushed rock, darkgray-brown, medium dense to dense, moistSILTY SAND WITH GRAVEL, red-brown,medium dense to dense, moistBOTTOM OF BORINGRefusal on cobble
DESCRIPTION
TESTS
V.W.PIEZO.DETAIL
GROUND SURFACE ELEV.:V.W. PIEZOMETER SENSOR ELEV.: ft
SAMPLES
US
CS
SY
MB
OL
WA
TE
RC
ON
TE
NT
, %
TY
PE
NU
MB
ER
DE
PT
H,
ft.
RE
CO
VE
RY
, in
.
SP
T -
NB
LOW
S /
ft.
DR
Y U
NIT
WT
pcf
Proposed Retail RedevelopmentSITE
BORING STARTED
WL
WL
WL
BORING COMPLETED
LOGGED BHS
RIG
12-15-10WD
82105050
PACLAND
DRILLER
CLIENT
LOG OF BORING NO. C-1
JOB #
GR
AP
HIC
LO
GPage 1 of 1
PROJECT
12-15-10
DCP (Dynamic Cone Penetrometer)
N/E
WATER LEVEL OBSERVATIONS, ft
17711 Jean WayLake Oswego, Oregon
The stratification lines represent the approximate boundary linesbetween soil and rock types: in-situ, the transition may be gradual.
V.W
. PIE
ZO
82
105
050.
GP
J T
ER
RA
CO
N.G
DT
12
/23
/10
SM
SM
1
2
3
DCPblows 24,
30/¾-inch, no
seatingloadDCP
blows 10,10, 25DCP
blows 30/1¼-inches
0.420.58
1.33
1.83
3
5-inch concrete slab with 1 #4 bar at3¼-inches below top of slabSAND, gray, moist,over black visqueen vapor retarderFILL: ¾-Inch minus crushed rock, darkgray-brown, medium dense to dense, moistFILL: gravelly sand with silt, (1½-Inchminus crushed rock), dark gray-brown,medium dense to dense, moistSILTY SAND WITH GRAVEL, red-brown,medium dense to dense, moistBOTTOM OF BORINGRefusal on cobble
DESCRIPTION
TESTS
V.W.PIEZO.DETAIL
GROUND SURFACE ELEV.:V.W. PIEZOMETER SENSOR ELEV.: ft
SAMPLES
US
CS
SY
MB
OL
WA
TE
RC
ON
TE
NT
, %
TY
PE
NU
MB
ER
DE
PT
H,
ft.
RE
CO
VE
RY
, in
.
SP
T -
NB
LOW
S /
ft.
DR
Y U
NIT
WT
pcf
Proposed Retail RedevelopmentSITE
BORING STARTED
WL
WL
WL
BORING COMPLETED
LOGGED BHS
RIG
12-15-10WD
82105050
PACLAND
DRILLER
CLIENT
LOG OF BORING NO. C-2
JOB #
GR
AP
HIC
LO
GPage 1 of 1
PROJECT
12-15-10
DCP (Dynamic Cone Penetrometer)
N/E
WATER LEVEL OBSERVATIONS, ft
17711 Jean WayLake Oswego, Oregon
The stratification lines represent the approximate boundary linesbetween soil and rock types: in-situ, the transition may be gradual.
V.W
. PIE
ZO
82
105
050.
GP
J T
ER
RA
CO
N.G
DT
12
/23
/10
SS
SS
SSDB
DB
CL
GM
GM
1
2
31
2
14
37
73/9"RQD14%
RQD25%
8
11
16
16
13
8
14
1
2.5
4
10
3-1/4" Asphalt over 12 inches 1" minuscrushed gravel, gray, moist (base course)
CLAY, with fine sand, brown, very stiff,moist, slightly plastic
SILTY GRAVEL, with sand, brown-gray,dense, moist- gray
-practical auger refusal @ 4'BASALT, slightly vesicular, interbeddedwith sand and gravels, gray, very slight toslight weathering, hard, close joints
BOTTOM OF BORING
Boring advanced using hollow-stem augermethods. At 4' Boring advanced usingDiamond bit coring to bottom of boring.
DESCRIPTION
TESTS
V.W.PIEZO.DETAIL
GROUND SURFACE ELEV.:V.W. PIEZOMETER SENSOR ELEV.: ft
SAMPLES
US
CS
SY
MB
OL
WA
TE
RC
ON
TE
NT
, %
TY
PE
NU
MB
ER
5
10
DE
PT
H,
ft.
RE
CO
VE
RY
, in
.
SP
T -
N *
*B
LOW
S /
ft.
DR
Y U
NIT
WT
pcf
Proposed Retail RedevelopmentSITE
BORING STARTED
B-50
WL
WL
WL
BORING COMPLETED
LOGGED JPH
MajorRIG
11-18-10WD
82105050
PACLAND
DRILLER
CLIENT
LOG OF BORING NO. P-1
JOB #
GR
AP
HIC
LO
GPage 1 of 1
PROJECT
11-18-10
**CME 140H SPT automatic hammer*Calibrated Hand Penetrometer
N/E
WATER LEVEL OBSERVATIONS, ft
17711 Jean WayLake Oswego, Oregon
The stratification lines represent the approximate boundary linesbetween soil and rock types: in-situ, the transition may be gradual.
V.W
. PIE
ZO
82
105
050.
GP
J T
ER
RA
CO
N.G
DT
12
/23
/10
SS
SS
SS
GM
GM
1
2
3
10
56/10"
62/10"
8
8
9
9
11
14
1
2.5
5.5
3-1/4" Asphalt over 8 inches 1" minuscrushed gravel (base course)
POSSIBLE FILL: SILTY GRAVEL, withsand, brown-gray, medium dense, damp
SILTY GRAVEL, with sand, brown-gray,very dense, damp
-refusal on bouldersBOTTOM OF BORING
Boring advanced using hollow-stem augermethods.
DESCRIPTION
TESTS
V.W.PIEZO.DETAIL
GROUND SURFACE ELEV.:V.W. PIEZOMETER SENSOR ELEV.: ft
SAMPLES
US
CS
SY
MB
OL
WA
TE
RC
ON
TE
NT
, %
TY
PE
NU
MB
ER
5D
EP
TH
, ft
.
RE
CO
VE
RY
, in
.
SP
T -
N *
*B
LOW
S /
ft.
DR
Y U
NIT
WT
pcf
Proposed Retail RedevelopmentSITE
BORING STARTED
B-50
WL
WL
WL
BORING COMPLETED
LOGGED JPH
MajorRIG
11-18-10WD
82105050
PACLAND
DRILLER
CLIENT
LOG OF BORING NO. P-2
JOB #
GR
AP
HIC
LO
GPage 1 of 1
PROJECT
11-18-10
**CME 140H SPT automatic hammer*Calibrated Hand Penetrometer
N/E
WATER LEVEL OBSERVATIONS, ft
17711 Jean WayLake Oswego, Oregon
The stratification lines represent the approximate boundary linesbetween soil and rock types: in-situ, the transition may be gradual.
V.W
. PIE
ZO
82
105
050.
GP
J T
ER
RA
CO
N.G
DT
12
/23
/10
SS
SS
SS
SM
SM
SM
1
2
3
21
14
63/9"
12
11
5
9
9
14
1
5.25
4" Asphalt over 9 inches 1" minus crushedgravel (base course)
SILTY SAND, with gravel, brown-gray,medium dense, moist
- gray, very dense, refusal on boulders
BOTTOM OF BORING
Boring advanced using hollow-stem augermethods.
DESCRIPTION
TESTS
V.W.PIEZO.DETAIL
GROUND SURFACE ELEV.:V.W. PIEZOMETER SENSOR ELEV.: ft
SAMPLES
US
CS
SY
MB
OL
WA
TE
RC
ON
TE
NT
, %
TY
PE
NU
MB
ER
5D
EP
TH
, ft
.
RE
CO
VE
RY
, in
.
SP
T -
N *
*B
LOW
S /
ft.
DR
Y U
NIT
WT
pcf
Proposed Retail RedevelopmentSITE
BORING STARTED
B-50
WL
WL
WL
BORING COMPLETED
LOGGED JPH
MajorRIG
11-18-10WD
82105050
PACLAND
DRILLER
CLIENT
LOG OF BORING NO. P-3
JOB #
GR
AP
HIC
LO
GPage 1 of 1
PROJECT
11-18-10
**CME 140H SPT automatic hammer*Calibrated Hand Penetrometer
N/E
WATER LEVEL OBSERVATIONS, ft
17711 Jean WayLake Oswego, Oregon
The stratification lines represent the approximate boundary linesbetween soil and rock types: in-situ, the transition may be gradual.
V.W
. PIE
ZO
82
105
050.
GP
J T
ER
RA
CO
N.G
DT
12
/23
/10
SS
SS
SS
SS
DB
GM
GM
GM
1
2
3
4
1
67/10"
24
35
50/3"
RQD25%
8
8
12
1
32
13
20
15
10
1
3
8
12
3 1/2" Asphalt over 9 inches 1" minuscrushed gravel (base course)
POSSIBLE FILL: SILTY GRAVEL, withsand, brown-gray, very dense (overstated),moist
SILTY GRAVEL, with sand, brown-red,medium dense, moist, weathered
- with sand, trace silt, brown-gray mottling,dense
- gray, possible bedrock, very dense, damp
BASALT, with interbedded gravel, veryslight weathering, gray, hard, close joints
BOTTOM OF BORING
Boring advanced using hollow-stem augermethods. At 7.5' Boring advanced usingDiamond bit coring to bottom of boring.
DESCRIPTION
TESTS
V.W.PIEZO.DETAIL
GROUND SURFACE ELEV.:V.W. PIEZOMETER SENSOR ELEV.: ft
SAMPLES
US
CS
SY
MB
OL
WA
TE
RC
ON
TE
NT
, %
TY
PE
NU
MB
ER
5
10
DE
PT
H,
ft.
RE
CO
VE
RY
, in
.
SP
T -
N *
*B
LOW
S /
ft.
DR
Y U
NIT
WT
pcf
Proposed Retail RedevelopmentSITE
BORING STARTED
B-50
WL
WL
WL
BORING COMPLETED
LOGGED JPH
MajorRIG
11-18-10WD
82105050
PACLAND
DRILLER
CLIENT
LOG OF BORING NO. P-4
JOB #
GR
AP
HIC
LO
GPage 1 of 1
PROJECT
11-18-10
**CME 140H SPT automatic hammer*Calibrated Hand Penetrometer
N/E
WATER LEVEL OBSERVATIONS, ft
17711 Jean WayLake Oswego, Oregon
The stratification lines represent the approximate boundary linesbetween soil and rock types: in-situ, the transition may be gradual.
V.W
. PIE
ZO
82
105
050.
GP
J T
ER
RA
CO
N.G
DT
12
/23
/10
SS
SS
SS
SS
SS
GM
CL
GM
GM
1
2
3
4
5
16
16
11
57
50/4"
6
6
12
12
3
18
18
15
13
12
1
3
5.5
7.5
10.5
2-1/2" Asphalt over 8 inches 1" minuscrushed gravel (base course)
POSSIBLE FILL: SILTY GRAVEL, withsand, brown, medium dense, moist
SILTY GRAVEL, with sand, gray-brown,medium dense, moist
CLAY, with fine sand, trace gravel, traceroots, brown, stiff, moist
SILTY GRAVEL, with sand, weathered,brown-gray-red mottling, very dense, moist
-trace sand
BOTTOM OF BORING
Boring advanced using hollow-stem augermethods.
DESCRIPTION
TESTS
V.W.PIEZO.DETAIL
GROUND SURFACE ELEV.:V.W. PIEZOMETER SENSOR ELEV.: ft
SAMPLES
US
CS
SY
MB
OL
WA
TE
RC
ON
TE
NT
, %
TY
PE
NU
MB
ER
5
10
DE
PT
H,
ft.
RE
CO
VE
RY
, in
.
SP
T -
N *
*B
LOW
S /
ft.
DR
Y U
NIT
WT
pcf
Proposed Retail RedevelopmentSITE
BORING STARTED
B-50
WL
WL
WL
BORING COMPLETED
LOGGED JPH
MajorRIG
11-18-10WD
82105050
PACLAND
DRILLER
CLIENT
LOG OF BORING NO. P-5
JOB #
GR
AP
HIC
LO
GPage 1 of 1
PROJECT
11-18-10
**CME 140H SPT automatic hammer*Calibrated Hand Penetrometer
N/E
WATER LEVEL OBSERVATIONS, ft
17711 Jean WayLake Oswego, Oregon
The stratification lines represent the approximate boundary linesbetween soil and rock types: in-situ, the transition may be gradual.
V.W
. PIE
ZO
82
105
050.
GP
J T
ER
RA
CO
N.G
DT
12
/23
/10
SS
SS
SS
GP
GP
1
2
3
21
20
25
12
8
11
1370
18
20
14
1
3.5
6.5
3-3/4" Asphalt over 8 inches 1" minuscrushed gravel (base course)
POSSIBLE FILL: CLAY, with sand, tracegravel, trace root hair, dark gray-brown,very stiff, moist
GRAVEL, gray, medium dense, damp
- with sand, trace silt, gray-brown
-practical auger refusal at 6.5' on boulderBOTTOM OF BORING
Boring advanced using hollow-stem augermethods.
DESCRIPTION
TESTS
V.W.PIEZO.DETAIL
GROUND SURFACE ELEV.:V.W. PIEZOMETER SENSOR ELEV.: ft
SAMPLES
US
CS
SY
MB
OL
WA
TE
RC
ON
TE
NT
, %
TY
PE
NU
MB
ER
5D
EP
TH
, ft
.
RE
CO
VE
RY
, in
.
SP
T -
N *
*B
LOW
S /
ft.
DR
Y U
NIT
WT
pcf
Proposed Retail RedevelopmentSITE
BORING STARTED
B-50
WL
WL
WL
BORING COMPLETED
LOGGED JPH
MajorRIG
11-18-10WD
82105050
PACLAND
DRILLER
CLIENT
LOG OF BORING NO. P-6
JOB #
GR
AP
HIC
LO
GPage 1 of 1
PROJECT
11-18-10
**CME 140H SPT automatic hammer*Calibrated Hand Penetrometer
N/E
WATER LEVEL OBSERVATIONS, ft
17711 Jean WayLake Oswego, Oregon
The stratification lines represent the approximate boundary linesbetween soil and rock types: in-situ, the transition may be gradual.
V.W
. PIE
ZO
82
105
050.
GP
J T
ER
RA
CO
N.G
DT
12
/23
/10
SS
SS
SS
SS
SS
GM
GM
GM
1
2
3
4
5
8
3
21
59
74/9"
4
4
8
16
8
1430
19
24
15
20
14
1
4.5
11.5
4" Asphalt over 20 inches 1" minuscrushed gravel (base course)
POSSIBLE FILL: GRAVEL, with sand,trace silt, gray, loose, saturated
-very loose
SILTY GRAVEL, with sand, dark brown,medium dense, saturated
- gray, very dense, saturated
BOTTOM OF BORING
Boring advanced using hollow-stem augermethods.
DESCRIPTION
TESTS
V.W.PIEZO.DETAIL
GROUND SURFACE ELEV.:V.W. PIEZOMETER SENSOR ELEV.: ft
SAMPLES
US
CS
SY
MB
OL
WA
TE
RC
ON
TE
NT
, %
TY
PE
NU
MB
ER
5
10
DE
PT
H,
ft.
RE
CO
VE
RY
, in
.
SP
T -
N *
*B
LOW
S /
ft.
DR
Y U
NIT
WT
pcf
Proposed Retail RedevelopmentSITE
BORING STARTED
B-50
WL
WL
WL
BORING COMPLETED
LOGGED JPH
MajorRIG
11-18-10WD
82105050
PACLAND
DRILLER
CLIENT
LOG OF BORING NO. P-7
JOB #
GR
AP
HIC
LO
GPage 1 of 1
PROJECT
11-18-10
**CME 140H SPT automatic hammer*Calibrated Hand Penetrometer
1
WATER LEVEL OBSERVATIONS, ft
17711 Jean WayLake Oswego, Oregon
The stratification lines represent the approximate boundary linesbetween soil and rock types: in-situ, the transition may be gradual.
V.W
. PIE
ZO
82
105
050.
GP
J T
ER
RA
CO
N.G
DT
12
/23
/10
Laboratory Testing Samples retrieved during the field exploration were taken to the laboratory for further observation by the project geotechnical engineer and were classified in general accordance with the Unified Soil Classification System (USCS) and local practice described in Appendix A. At that time, the field descriptions were confirmed or modified as necessary and an applicable laboratory testing program was formulated to determine engineering properties of the subsurface materials. Laboratory tests were conducted on selected soil samples and the test results are presented in this appendix. The laboratory test results were used for the geotechnical engineering analyses, and the development of foundation and earthwork recommendations. Laboratory tests were performed in general accordance with the applicable ASTM, local or other accepted standards. Selected soil samples obtained from the site were tested for the following engineering properties:
Moisture Content California Bearing Ratio
Grain Size Distribution Resistivity and pH Atterberg Limits Standard Proctor
Testing not Completed for this Project BTEX – No BTEX testing was completed as we are not aware of any gas station proposed as part of the expansion project. Topsoil – No topsoil was encountered during our explorations. Consolidation – No areas of fill or building loads are planned that would warrant consolidation testing. Unconfined Compressive Strength and Dry Unit Weight – Shelby tubes were not pushed due to the gravelly nature of the site soils.
CALIFORNIA BEARING RATIO ASTM D 1883
P-1 to P-5 Soil Description: silty GRAVEL with sandComposite Tested By: EJL/JJI
Depth: 2 Comments: 10 percent retained on 3/4" sieve
10 Blows/Lift 25 Blows/Lift 56 Blows/LiftCondition of Sample: soaked soaked soakedDry Density Before Soaking: 117 pcf 124 pcf 125 pcfDry Density After Soaking: 118 pcf 124 pcf 125 pcfMoisture Content: Before Compaction: 13.4 % 12.9 % 13.5 % After Compaction: 13.4 % 12.9 % 13.5 % Top 1-in Layer After Soaking: 14.1 % 14.3 % 13.5 % Average After Soaking: 14.0 %Swell: -0.1 % -0.2 % -0.2 %Surcharge Amount: 64.8 psf 64.8 psf 64.8 psf
Sample No.:Exploration:
20
25
CBR Curve
130
135
Compaction Curve
ASTM D 698
Max. Dry Density (MDD) = 123 pcf 95% of MDD = 116.9 pcfOptimum Moisture = 13.5 % CBR at 95% of MDD = 10
TERRACON CONSULTANTS, INC.GEOTECHNICAL AND ENVIRONMENTAL
CONSULTING
PROJECT NO: PROJECT NAME:
DATE OF TESTING:
82105050
12/14/10 Proposed Retail Redevelopment
0
5
10
15
20
25
115 120 125 130
Cor
rect
ed C
BR
Dry Density (pcf)
CBR Curve
Lab Data Points
CBR at 95% MDD
110
115
120
125
130
135
0.0 5.0 10.0 15.0 20.0
Dry
Den
sity
(p
cf)
Moisture Content (%)
Compaction Curve
ASTM D 698
P-3
GRAVELCOBBLES
23 140
P-7
P-2Composite
%Clay
100
55
0.001
25
30
35
40
45
0.1
50
1
60
65
70
75
80
85
90
95
1004
0.010
5
10
15
20
100 10
57.9
PI Cc
44.70.867
38.4
28.122.214.616.7
59.4
6
SAND
2.116
200
coarse
D100
810
D30
Cu
D60
2.5ft
SILTY SAND WITH GRAVEL (SM)SILTY GRAVEL WITH SAND (GM)
GRAIN SIZE DISTRIBUTION
2.5ft2.5ft1.0ft
SILTY GRAVEL WITH SAND (GM)
2.5ft
U.S. SIEVE NUMBERS
1.0ft5.0ft
Project: Proposed Retail RedevelopmentSite: 17711 Jean Way Lake Oswego, OregonJob #: 82105050Date: 12-23-10
5.0ft
0.109
SILTY GRAVEL WITH SAND (GM)
60
fine
HYDROMETERU.S. SIEVE OPENING IN INCHES
Specimen Identification
3
%Gravel %Sand
0.97
Specimen Identification Classification
504
%Silt
TC_G
RA
IN_S
IZE
821
0505
0.G
PJ
TE
RR
AC
ON
.GD
T 1
2/23
/10
CompositeP-2P-3P-7
141.5 16 20 30 403/4
25.4
27.2
47.0
medium
5.69614.4754.44311.397
1937.51925
18.4
GRAIN SIZE IN MILLIMETERS
SILT OR CLAY
1/23/8
LL PL
6 1
PE
RC
EN
T FI
NE
R B
Y W
EIG
HT
D10
fine coarse
CLAY (CL)
P-1
P-5
P-6
CLAY (CL)
CLAY (CL)
100
50
40
30
20
0 20 40 80
10
0
60
60
Classification
33
LL PL %Fines
1.0ft
5.0ft
25
ATTERBERG LIMITS RESULTS
17
18
23
8
10
10
Project: Lake Oswego RetailSite: 17711 Jean Way Lake Oswego, OregonJob #: 82105050Date: 12-21-10
1.0ft
CLTC
_ATT
ER
BE
RG
_LIM
ITS
821
0505
0.G
PJ
TE
RR
AC
ON
.GD
T 1
2/21
/10
PISpecimen Identification
28
ML
MH
CH
CL-ML
PLASTICITY
INDEX
LIQUID LIMIT
PORTLAND, OR 9405 S.W. NIMBUS AVENUE
BEAVERTON, OR 97008-7132
ph: (503) 906.9200 fax: (503) 906.9210
ORELAP#: OR100021
Eric Lim
Terraon - Portland
4103 SE International Way, Suite 300
Portland, OR 97222
RE: Lake Oswego Retail
Enclosed are the results of analyses for samples received by the laboratory on 12/20/10 18:50.
The following list is a summary of the Work Orders contained in this report, generated on 12/22/10
12:12.
If you have any questions concerning this report, please feel free to contact me.
December 22, 2010
ProjectNumberProjectWork Order
82104040 L.O.R.Lake Oswego RetailPTL0751
TestAmerica Portland The results in this report apply to the samples analyzed in accordance with the chain
of custody document. This analytical report shall not be reproduced except in full,
without the written approval of the laboratory.
Darrell Auvil, Project Manager
w w w . t e s t a m e r i c a i n c . c o m Page 1 of 5
PORTLAND, OR 9405 S.W. NIMBUS AVENUE
BEAVERTON, OR 97008-7132
ph: (503) 906.9200 fax: (503) 906.9210
Lake Oswego Retail
Portland, OR 97222
Report Created:
Project Manager:
Project Number:
Project Name:
12/22/10 12:12Eric Lim
82104040 L.O.R.4103 SE International Way, Suite 300
Terraon - Portland
ANALYTICAL REPORT FOR SAMPLES
Sample ID Laboratory ID Matrix Date Sampled Date Received
C-1@24'' PTL0751-01 12/20/10 15:55 12/20/10 18:50Soil
C-2@27'' PTL0751-02 12/20/10 16:00 12/20/10 18:50Soil
P-6@12'' PTL0751-03 12/20/10 16:05 12/20/10 18:50Soil
TestAmerica Portland The results in this report apply to the samples analyzed in accordance with the chain
of custody document. This analytical report shall not be reproduced except in full,
without the written approval of the laboratory.
Darrell Auvil, Project Manager
w w w . t e s t a m e r i c a i n c . c o m Page 2 of 5
PORTLAND, OR 9405 S.W. NIMBUS AVENUE
BEAVERTON, OR 97008-7132
ph: (503) 906.9200 fax: (503) 906.9210
Lake Oswego Retail
Portland, OR 97222
Report Created:
Project Manager:
Project Number:
Project Name:
12/22/10 12:12Eric Lim
82104040 L.O.R.4103 SE International Way, Suite 300
Terraon - Portland
TestAmerica Portland
Conventional Chemistry Parameters per APHA/EPA Methods
Analyte Method Result UnitsMRLMDL* Dil Batch AnalyzedPrepared Notes
PTL0751-01 (C-1@24'') Soil Sampled: 12/20/10 15:55
pH 10L0623 12/21/10 14:251x7.60EPA 9045C pH Units ----- 12/21/10 09:37
PTL0751-02 (C-2@27'') Soil Sampled: 12/20/10 16:00
pH 10L0623 12/21/10 14:251x6.85EPA 9045C pH Units ----- 12/21/10 09:37
PTL0751-03 (P-6@12'') Soil Sampled: 12/20/10 16:05
pH 10L0623 12/21/10 14:251x7.42EPA 9045C pH Units ----- 12/21/10 09:37
TestAmerica Portland The results in this report apply to the samples analyzed in accordance with the chain
of custody document. This analytical report shall not be reproduced except in full,
without the written approval of the laboratory.
Darrell Auvil, Project Manager
w w w . t e s t a m e r i c a i n c . c o m Page 3 of 5
PORTLAND, OR 9405 S.W. NIMBUS AVENUE
BEAVERTON, OR 97008-7132
ph: (503) 906.9200 fax: (503) 906.9210
Lake Oswego Retail
Portland, OR 97222
Report Created:
Project Manager:
Project Number:
Project Name:
12/22/10 12:12Eric Lim
82104040 L.O.R.4103 SE International Way, Suite 300
Terraon - Portland
TestAmerica Portland
Conventional Chemistry Parameters per APHA/EPA Methods - Laboratory Quality Control Results
Soil Preparation Method: General PreparationQC Batch: 10L0623
Analyte Method Result UnitsMRL MDL*AmtSpike
ResultSource
REC(Limits)
RPD(Limits) Analyzed Notes %Dil %
Extracted: 12/21/10 09:38Duplicate (10L0623-DUP1) QC Source: PTL0751-01
--- -- 6.24%7.60 -- 12/21/10 14:25pH pH Units (25)--EPA 9045C 1x7.14
TestAmerica Portland The results in this report apply to the samples analyzed in accordance with the chain
of custody document. This analytical report shall not be reproduced except in full,
without the written approval of the laboratory.
Darrell Auvil, Project Manager
w w w . t e s t a m e r i c a i n c . c o m Page 4 of 5
PORTLAND, OR 9405 S.W. NIMBUS AVENUE
BEAVERTON, OR 97008-7132
ph: (503) 906.9200 fax: (503) 906.9210
Lake Oswego Retail
Portland, OR 97222
Report Created:
Project Manager:
Project Number:
Project Name:
12/22/10 12:12Eric Lim
82104040 L.O.R.4103 SE International Way, Suite 300
Terraon - Portland
Notes and Definitions
Report Specific Notes:
None
Laboratory Reporting Conventions:
Reporting Limits
Sample results reported on a Dry Weight Basis. Results and Reporting Limits have been corrected for Percent Dry Weight.dry
Analyte NOT DETECTED at or above the reporting limit (MDL or MRL, as appropriate).ND
NR/NA Not Reported / Not Available
wet Sample results and reporting limits reported on a Wet Weight Basis (as received). Results with neither 'wet' nor 'dry' are reported
on a Wet Weight Basis.
Analyte DETECTED at or above the Reporting Limit. Qualitative Analyses only.DET
METHOD DETECTION LIMIT. Reporting Level at, or above, the statistically derived limit based on 40CFR, Part 136, Appendix B.
*MDLs are listed on the report only if the data has been evaluated below the MRL. Results between the MDL and MRL are reported
as Estimated Results.
MDL*
METHOD REPORTING LIMIT. Reporting Level at, or above, the lowest level standard of the Calibration Table.MRL
RELATIVE PERCENT DIFFERENCE (RPDs calculated using Results, not Percent Recoveries). RPD
Dil Dilutions are calculated based on deviations from the standard dilution performed for an analysis, and may not represent the dilution
found on the analytical raw data.
Reporting limits (MDLs and MRLs) are adjusted based on variations in sample preparation amounts, analytical dilutions and
percent solids, where applicable.
-
-
-
-
-
-
-
-
-
-
Electronic
Signature
Electronic Signature added in accordance with TestAmerica's Electronic Reporting and Electronic Signatures Policy.
Application of electronic signature indicates that the report has been reviewed and approved for release by the laboratory. Electronic signature is intended to be the legally binding equivalent of a traditionally handwritten signature.
-
TestAmerica Portland The results in this report apply to the samples analyzed in accordance with the chain
of custody document. This analytical report shall not be reproduced except in full,
without the written approval of the laboratory.
Darrell Auvil, Project Manager
w w w . t e s t a m e r i c a i n c . c o m Page 5 of 5
CERTIFICATION SUMMARY
Method Matrix
TestAmerica Portland
Oregon
Soil XEPA 9045C
TestAmerica Portland The results in this report apply to the samples analyzed in accordance with the chain
of custody document. This analytical report shall not be reproduced except in full,
without the written approval of the laboratory.
Darrell Auvil, Project Manager
w w w . t e s t a m e r i c a i n c . c o m Page 1 of 2
PORTLAND, OR 9405 S.W. NIMBUS AVENUE
BEAVERTON, OR 97008-7132
ph: (503) 906.9200 fax: (503) 906.9210
Lake Oswego Retail
Portland, OR 97222
Report Created:
Project Manager:
Project Number:
Project Name:
12/22/10 12:12Eric Lim
82104040 L.O.R.4103 SE International Way, Suite 300
Terraon - Portland
NELAC CERTIFICATION SUMMARY
TestAmerica Analytical - Portland does not hold NELAC certifications for the following analytes included in this report
Method Matrix Analyte
TestAmerica Portland The results in this report apply to the samples analyzed in accordance with the chain
of custody document. This analytical report shall not be reproduced except in full,
without the written approval of the laboratory.
Darrell Auvil, Project Manager
w w w . t e s t a m e r i c a i n c . c o m Page 2 of 2
GENERAL NOTES
DRILLING & SAMPLING SYMBOLS: SS: Split Spoon – 1-3/8" I.D., 2" O.D., unless otherwise noted HS: Hollow Stem Auger ST: Thin-Walled Tube - 3" O.D., unless otherwise noted PA: Power Auger RS: Ring Sampler - 2.42" I.D., 3" O.D., unless otherwise noted HA: Hand Auger DB: Diamond Bit Coring - 4", N, B RB: Rock Bit BS: Bulk Sample or Auger Sample WB: Wash Boring or Mud Rotary
The number of blows required to advance a standard 2-inch O.D. split-spoon sampler (SS) the last 12 inches of the total 18-inch penetration with a 140-pound hammer falling 30 inches is considered the “Standard Penetration” or “N-value”.
WATER LEVEL MEASUREMENT SYMBOLS:
WL: Water Level WS: While Sampling N/E: Not Encountered WCI: Wet Cave in WD: While Drilling DCI: Dry Cave in BCR: Before Casing Removal AB: After Boring ACR: After Casing Removal
Water levels indicated on the boring logs are the levels measured in the borings at the times indicated. Groundwater levels at other times and other locations across the site could vary. In pervious soils, the indicated levels may reflect the location of groundwater. In low permeability soils, the accurate determination of groundwater levels may not be possible with only short-term observations.
DESCRIPTIVE SOIL CLASSIFICATION: Soil classification is based on the Unified Soil Classification System. Coarse Grained Soils have more than 50% of their dry weight retained on a #200 sieve; their principal descriptors are: boulders, cobbles, gravel or sand. Fine Grained Soils have less than 50% of their dry weight retained on a #200 sieve; they are principally described as clays if they are plastic, and silts if they are slightly plastic or non-plastic. Major constituents may be added as modifiers and minor constituents may be added according to the relative proportions based on grain size. In addition to gradation, coarse-grained soils are defined on the basis of their in-place relative density and fine-grained soils on the basis of their consistency.
CONSISTENCY OF FINE-GRAINED SOILS RELATIVE DENSITY OF COARSE-GRAINED SOILS
Unconfined Compressive
Strength, Qu, psf
Standard Penetration or N-value (SS)
Blows/Ft. Consistency
Standard Penetration or N-value (SS)
Blows/Ft.
Ring Sampler (RS) Blows/Ft.
Relative Density
< 500 0-1 Very Soft 0 – 3 0-6 Very Loose 500 – 1,000 2-3 Soft 4 – 9 7-18 Loose
1,001 – 2,000 4-6 Medium Stiff 10 – 29 19-58 Medium Dense 2,001 – 4,000 7-12 Stiff 30 – 49 59-98 Dense 4,001 – 8,000 13-26 Very Stiff 50+ 99+ Very Dense
8,000+ 26+ Hard
RELATIVE PROPORTIONS OF SAND AND GRAVEL GRAIN SIZE TERMINOLOGY
Descriptive Term(s) of other Constituents
Percent ofDry Weight
Major Componentof Sample
Particle Size
Trace < 15 Boulders Over 12 in. (300mm) With 15 – 30 Cobbles 12 in. to 3 in. (300mm to 75 mm)
Modifier > 30 Gravel 3 in. to #4 sieve (75mm to 4.75 mm)
Sand
Silt or Clay #4 to #200 sieve (4.75mm to 0.075mm)
Passing #200 Sieve (0.075mm)
RELATIVE PROPORTIONS OF FINES PLASTICITY DESCRIPTION
Descriptive Term(s) of other Constituents
Percent ofDry Weight
Term Plasticity
Index
Trace < 5 Non-plastic 0 With 5 – 12 Low 1-10
Modifier > 12 Medium 11-30 High 30+
Exhibit C-1
Form 111—6/98
UNIFIED SOIL CLASSIFICATION SYSTEM
Criteria for Assigning Group Symbols and Group Names Using Laboratory TestsA Soil Classification
Group Symbol
Group NameB
Cu 4 and 1 Cc 3E GW Well-graded gravelF Clean Gravels Less than 5% finesC
Cu 4 and/or 1 Cc 3E GP Poorly graded gravelF
Fines classify as ML or MH GM Silty gravelF,G, H
Coarse Grained Soils
More than 50% retained
on No. 200 sieve
Gravels More than 50% of coarse fraction retained on No. 4 sieve Gravels with Fines More
than 12% finesC Fines classify as CL or CH GC Clayey gravelF,G,H
Cu 6 and 1 Cc 3E SW Well-graded sandI Clean Sands Less than 5% finesD
Cu 6 and/or 1 Cc 3E SP Poorly graded sandI
Fines classify as ML or MH SM Silty sandG,H,I
Sands 50% or more of coarse fraction passes No. 4 sieve Sands with Fines
More than 12% finesD Fines Classify as CL or CH SC Clayey sandG,H,I
PI 7 and plots on or above “A” lineJ CL Lean clayK,L,M Silts and Clays Liquid limit less than 50
inorganic
PI 4 or plots below “A” lineJ ML SiltK,L,M
Liquid limit - oven dried Organic clayK,L,M,N
Fine-Grained Soils 50% or more passes the No. 200 sieve
organic
Liquid limit - not dried 0.75 OL
Organic siltK,L,M,O
inorganic PI plots on or above “A” line CH Fat clayK,L,M
Silts and Clays Liquid limit 50 or more
PI plots below “A” line MH Elastic SiltK,L,M
Liquid limit - oven dried Organic clayK,L,M,P organic
Liquid limit - not dried 0.75 OH
Organic siltK,L,M,Q
Highly organic soils Primarily organic matter, dark in color, and organic odor PT Peat
A Based on the material passing the 3-in. (75-mm) sieve B If field sample contained cobbles or boulders, or both, add “with cobbles
or boulders, or both” to group name. C Gravels with 5 to 12% fines require dual symbols: GW-GM well-graded
gravel with silt, GW-GC well-graded gravel with clay, GP-GM poorly graded gravel with silt, GP-GC poorly graded gravel with clay.
D Sands with 5 to 12% fines require dual symbols: SW-SM well-graded sand with silt, SW-SC well-graded sand with clay, SP-SM poorly graded sand with silt, SP-SC poorly graded sand with clay
E Cu = D60/D10 Cc = 6010
230
DxD
)(D
F If soil contains 15% sand, add “with sand” to group name. G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM.
HIf fines are organic, add “with organic fines” to group name. I If soil contains 15% gravel, add “with gravel” to group name. J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay. K If soil contains 15 to 29% plus No. 200, add “with sand” or “with
gravel,” whichever is predominant. L If soil contains 30% plus No. 200 predominantly sand, add
“sandy” to group name. M If soil contains 30% plus No. 200, predominantly gravel, add
“gravelly” to group name. N PI 4 and plots on or above “A” line. O PI 4 or plots below “A” line. P PI plots on or above “A” line. Q PI plots below “A” line.
OREGON CITY, OREGON (356334) Period of Record Monthly Climate Summary
Period of Record : 11/1/1911 to 7/31/2010
Percent of possible observations for period of record. Max. Temp.: 98.3% Min. Temp.: 98.1% Precipitation: 98.4% Snowfall: 98.1% Snow Depth: 97.5% Check Station Metadata or Metadata graphics for more detail about data completeness.
Western Regional Climate Center, [email protected]
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec AnnualAverage Max. Temperature (F)
46.9 52.2 56.7 62.8 69.6 75.5 82.4 82.0 76.9 64.8 53.3 47.1 64.2
Average Min. Temperature (F)
35.2 36.9 38.8 41.9 46.9 51.8 55.1 55.1 51.5 45.4 39.8 35.9 44.5
Average Total Precipitation (in.) 7.16 5.06 4.91 3.32 2.48 1.83 0.64 1.02 1.94 3.63 6.78 7.40 46.18
Average Total SnowFall (in.) 2.4 0.7 0.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.9 4.4
Average Snow Depth (in.)
0 0 0 0 0 0 0 0 0 0 0 0 0
Page 1 of 1OREGON CITY, OREGON Period of Record Monthly Climate Summary
12/19/2010http://www.wrcc.dri.edu/cgi-bin/cliRECtM.pl?or6334
Design Inputs Asphalt ConcreteSugrade Support CBR = 10
Mr = 10000 psi k = 200 pciReliability 85 % 85 %Standard Deviation So = 0.45 0.35Initial Serviceability Po = 4.2 4.2Terminal Serviceability Pt = 2.0 2.0Design Serviceability Loss, PSI = 2.2 2.2
Layer Coefficients:AC Surface and Binder a1 = 0.42
Aggregate Base a2 = 0.14
Concrete Compressive Strength = 4000 psiModulus of Elasticity of Concrete = 3,600 ksiModulus of Rupture of Concrete: = 580
Load Transfer ("J" Factor) = 3.6Drainage Coefficient = 1.0
Pavement Design(AASHTO 1993 Method)
Standard DutyAsphalt Section Traffic (18 kip ESAL) = 109,500
Asphalt Pavement Section Drainage, mAC Surface + Binder 3.0 in.
in.Aggregate Base 1.0 6.0 in.
Structural Number: 2.10
Structural Number - Required 2.04
Standard DutyConcrete Section Traffic (18 kip ESAL) = 109,500
Concrete Pavement Section 5.0 in.
Project: Proposed Retail Redevelopment Location: Lake Oswego, Oregon
Project No. 82105050 Date: 12/20/10
Design Inputs Asphalt ConcreteSugrade Support CBR = 10
Mr = 10000 psi k = 200 pciReliability 85 % 85 %Standard Deviation So = 0.45 0.35Initial Serviceability Po = 4.2 4.2Terminal Serviceability Pt = 2.0 2.0Design Serviceability Loss, PSI = 2.2 2.2
Layer Coefficients:AC Surface and Binder a1 = 0.42
Aggregate Base a2 = 0.14
Concrete Compressive Strength = 4000 psiModulus of Elasticity of Concrete = 3,600 ksiModulus of Rupture of Concrete: = 580
Load Transfer ("J" Factor) = 3.6Drainage Coefficient = 1.0
Pavement Design(AASHTO 1993 Method)
Heavy DutyAsphalt Section Traffic (18 kip ESAL) = 211,700
Asphalt Pavement Section Drainage, mAC Surface + Binder 4.0 in.
in.Aggregate Base 1.0 6.0 in.
Structural Number: 2.52
Structural Number - Required 2.27
Heavy DutyConcrete Section Traffic (18 kip ESAL) = 211,700
Concrete Pavement Section 5.4 in.
Project: Proposed Retail Redevelopment Location: Lake Oswego, Oregon
Project No. 82105050 Date: 12/20/10
GEOTECHNICAL INVESTIGATION FACT SHEET PROJECT LOCATION: 17711 Jean Way, Lake Oswego, Oregon
Engineer: Eric J. Lim, PE, GE Phone #: 503.659.3281
Geotechnical Engineering Co.: Terracon Consultants, Inc. Report Date: March 16, 2012
Ground Water Elevation: 161.5 ft (1-ft bgs, boring P-7 only)
Fill Soils Characteristics: Maximum Liquid Limit: 30 Maximum Plasticity Index: 0
Specified Compaction: Percent of Maximum Laboratory Density Location ASTM D 698 ASTM D 1557
Subgrade & Fill below Structures 98 95 Upper 2 feet of Pavement Subgrades 98 95 Below 2 feet of Pavement Subgrades 95 92
Moisture Content: Granular soils ±2 of optimum (ASTM D 1557) Fine-grained soils -1 to +3 optimum (ASTM D 698) Date Groundwater Measured: November 2010
Topsoil/Stripping Depth: N/A
Undercut: 2 feet under footings.
Proctor Results: Shown on attached CBR plot in Appendix B.
pH: Native soils 6.85 to 7.60
Corrective actions required for construction based on pH level noted: none
Resistivity: 2,700 to 3,400 ohms*cm
Corrective actions required for construction based on resistivity level noted: Polyethylene encasement of ductile
iron. Galvanized, aluminized, or polymer coated corrugated metal.
Cement Type: Type I or Type II
Recommended local DOT subbase/base material:
Base: Oregon Standard Specification 02630.10 Dense Graded Aggregate (1”-0) with less than 8% passing #200 sieve.
Subbase: Oregon Standard Specification 00330.14 Selected Granular Backfill with exception of no more than 8% passing
the No. 200 sieve by weight
Recommended Compaction Control Tests:
1 Test for Each 2,500 Sq. Ft. each Lift (bldg. area), 1 Test for Each 10,000 Sq. Ft. each Lift (parking area)
Structural Fill Maximum Lift Thickness: 8 inches (Measured loose)
Subgrade Design CBR value = 10
Minimum Recommended Overlay Pavement Thickness (in)
Traffic Area Asphalt Concrete Overlay Thickness (in)
Standard-Duty to Standard-Duty Pavements 1½
Standard-Duty to Heavy-Duty Pavements 1½
Heavy-Duty to Heavy-Duty Pavements 1½
Minimum Recommended Pavement Thickness (in)
Traffic Area Pavement
Material
Asphalt Concrete
Thickness (in)
Portland Cement
Concrete Thickness
(in)
Base Course
Thickness
(in)
Subbase
Thickness (in)
Total
Thickness
(in)
Standard-Duty
Pavements
ACP 3.0 - 6.0 - 9.0
PCC - 5.0 4.0 - 9.0
Heavy-Duty
Pavements
ACP 4.0 - 6.0 - 10.0
PCC - 6.0 4.0 - 10.0
Truck Loading and
Dumpster Pad PCC - 7.0 4.0 - 11.0
NOTE: This information shall not be used separately from the geotechnical report.
FOUNDATION DESIGN CRITERIA PROJECT LOCATION: 17711 Jean Way, Lake Oswego, Oregon Engineer: Eric J. Lim, PE, GE Phone #: 503.659.3281 Geotechnical Engineering Co.: Terracon Consultants, Inc. Report Date: March 16, 2012 Foundation type: Spread and continuous footings supported on a minimum two feet Select Fill. Allowable bearing pressure: 2,500 psf Factor of Safety: 2 Minimum footing dimensions: Individual: 24 inches Continuous: 18 inches Minimum footing embedment: Exterior: 18 inches Interior: 12 inches Frost depth: 18 inches Maximum foundation settlements: Total: ¾ inch Differential: ½ inch Slab: Potential vertical rise: < ¾ inch Capillary Break: 15 inches of crushed aggregate base course over subgrade soils compacted to 95 percent of modified Proctor maximum dry density (ASTM D 1557) for granular soils or 98 percent of modified Proctor maximum dry density (ASTM D 698) for fine-grained soils. Subgrade reaction modulus: 200 psi/in. Method obtained: CBR Correlation. Active Equivalent Fluid Pressures: 35 pcf for structural fill material Passive Equivalent Fluid Pressures: 250 pcf for structural fill material COMMENTS: This information shall not be used separately from the Geotechnical Report.
FOUNDATION SUBSURFACE PREPARATION NOTES LAKE OSWEGO, OREGON MARCH 16, 2012
UNLESS SPECIFICALLY INDICATED OTHERWISE IN THE DRAWINGS AND/OR SPECIFICATIONS, THE LIMITS OF THIS SUBSURFACE PREPARATION ARE CONSIDERED TO BE THAT PORTION OF THE SITE DIRECTLY BENEATH AND 5 FEET BEYOND THE BUILDING AND APPURTENANCES. APPURTENANCES ARE THOSE ITEMS ATTACHED TO THE BUILDING PROPER (REFER TO DRAWING SHEET A1) TYPICALLY INCLUDING, BUT NOT LIMITED TO, THE BUILDING SIDEWALKS, PORCHES, RAMPS, STOOPS, TRUCK DOCKS, CONCRETE APRONS, COMPACTOR PAD, ETC. THE BASE DOES NOT EXTEND BEYOND THE LIMITS OF THE ACTUAL BUILDING AND THE APPURTENANCES.
FOR NEW CONCRETE SLAB AREAS, ESTABLISH THE FINAL SUBGRADE ELEVATION TO ALLOW FOR THE CONCRETE SLAB AND BASE. FOR EXISTING CONCRETE SLAB AREAS, REMOVE THE EXISTING SLAB IN THE AREAS SHOWN ON THE DEMOLITION PLAN AND INSTALL UTILITIES AS INDICATED ON THE PLANS. INTERIOR EXCAVATED TRENCHES SHALL BE BACKFILLED PER THE STRUCTURAL PLAN TRENCH DETAIL, REF 5-S2. IN TRENCH AREAS, ESTABLISH THE FINAL SUBGRADE ELEVATION TO ALLOW FOR THE CONCRETE SLAB AND BASE. IN UNDISTURBED SLAB BASE AREAS, THE CONTRACTOR SHALL COMPACT THE EXISTING BASE TO AT LEAST THE MINIMUM COMPACTION LEVEL SPECIFIED IN SECTION 02300. REFERENCE ARCHITECTURAL AND STRUCTURAL DRAWINGS FOR REQUIRED SLAB THICKNESS. THE BASE MATERIAL SHALL MATCH THE EXISTING BASE THICKNESS BUT NOT LESS THAN 15 INCHES IN THICKNESS AND CONFORM TO THE PRODUCT REQUIREMENTS PRESENTED IN SPECIFICATION SECTION 02300. THE CONTRACTOR SHALL BE RESPONSIBLE FOR OBTAINING ACCURATE MEASUREMENTS FOR ALL CUT AND FILL DEPTHS REQUIRED. ANY PROPOSED EQUIVALENT ALTERNATIVE BASE MATERIAL MUST BE SUBMITTED FOR APPROVAL WITHIN 30 DAYS AFTER AWARD OF CONTRACT. ANY EQUIVALENT ALTERNATIVE SHALL ONLY BE USED IF APPROVED IN WRITING BY THE RETAILER’S CONSTRUCTION MANAGER, CEC, AND AOR.
OBSTRUCTIONS ENCOUNTERED DURING PREPARATION OF SUBGRADES SHALL BE REMOVED FROM THE BUILDING IMPROVEMENT AREAS. UNDERGROUND UTILITIES WITHIN THE PROPOSED BUILDING PAD IMPROVEMENTS SHALL BE PRESERVED AND PROTECTED FOR FUTURE OPERATIONAL USE OR: (A) COMPLETELY REMOVED AND THE RESULTING EXCAVATIONS BACKFILLED WITH SATISFACTORY FILL MATERIAL AS SHOWN ON THE CIVIL PLANS; OR (B) THE UTILITIES WILL BE GROUTED IN-PLACE AND THE EXISTING TRENCH BACKFILL DENSITY TESTED TO DETERMINE THAT THE MINIMUM REQUIRED COMPACTION LEVELS HAVE BEEN ACHIEVED. REMOVE AND REPLACE UNSATISFACTORY MATERIALS WITH SATISFACTORY FILL MATERIAL PER SPECIFICATION SECTION 02300 AND/OR STABILIZATION MATERIALS PER SECTION 02340. PRIOR TO PLACING SATISFACTORY FILL MATERIALS OR CONSTRUCTING FLOOR SLABS, THE UPPER FOOT OF EXPOSED SUBGRADES SHALL BE COMPACTED TO A MINIMUM OF 95 PERCENT OF THE MODIFIED PROCTOR MAXIMUM DRY DENSITY (ASTM D 1557) FOR GRANULAR SOILS OR 98 PERCENT OF THE STANDARD PROCTOR MAXIMUM DRY DENSITY (ASTM D 698) FOR FINE-GRAINED SOILS. COMPACT EXPOSED SUBGRADE IN THE PRESENCE OF THE OWNER’S CTL. WHERE EXCAVATIONS PENETRATE EXISTING FLOOR SLABS, THE SLAB SAWCUT SHALL BE LOCATED AT LEAST 6 INCHES OUTSIDE THE PLANNED TRENCH EDGES AND THE EXISTING CAPILLARY BREAK / BASE COURSE MATERIAL SHALL BE RETAINED SO AS TO NOT UNDERMINE THE SURROUNDING SLAB. EXCAVATIONS SHALL NOT ENCROACH UPON THE BEARING SOIL OF EXISTING FOUNDATIONS. THE BEARING SOIL IS DEFINED AS THE PRISM OF SOIL BENEATH A LINE THAT EXTENDS DOWN AND AWAY FROM THE BOTTOM EDGES OF A FOOTING AT 3 HORIZONTAL TO 2 VERTICAL. WHEN ENCROACHMENT CANNOT BE AVOIDED, THE CONTRACTOR SHALL NOTIFY THE RETAILER AND SHALL NOT PROCEED UNTIL FURTHER INSTRUCTION FROM RETAILER.
FILL SHALL COMPLY WITH CRITERIA FOR SATISFACTORY FILL MATERIALS IN SPECIFICATION SECTION 02300, BE PLACED IN LOOSE LIFTS NOT EXCEEDING 8 INCHES IN THICKNESS, AND COMPACTED TO THE MINIMUM SPECIFIED LEVELS PRESENTED IN SPECIFICATION SECTION 02300 AT A MOISTURE CONTENT WITHIN 2 PERCENT BELOW TO 2 PERCENT ABOVE THE OPTIMUM FOR GRANULAR SOILS.
THE FOUNDATION SYSTEM FOR THE BUILDING IMPROVEMENTS SHALL BE SPREAD FOOTING PADS AT COLUMNS AND CONTINUOUS SPREAD FOOTINGS. FOOTINGS SHALL BE SUPPORTED ON A MINIMUM 2-FOOT-THICK LAYER OF SELECT FILL MATERIAL PLACED AND COMPACTED IN ACCORDANCE WITH SPECIFICATION SECTION 02300. WHERE OVEREXCAVATIONS FOR NEW FOOTINGS WILL ENCROACH THE BEARING SOILS PRISM OF EXISTING FOOTINGS AS DESCRIBED ABOVE, THE OVEREXCAVATIONS SHALL BE STEPPED DOWN INCREMENTALLY AT A 1H:1V AS SHOWN ON THE PLANS TO THE DESIGN OVEREXCAVATION DEPTH. OVEREXCAVATIONS WITHIN 5 FEET OF EXISTING FOOTINGS SHALL BE BACKFILLED PROMPTLY AND SHALL NOT BE LEFT OPEN OVERNIGHT.
THIS SUBSURFACE PREPARATION DOES NOT CONSTITUTE A COMPLETE SITE WORK SPECIFICATION. IN CASE OF CONFLICT, INFORMATION COVERED IN THIS PREPARATION SHALL TAKE PRECEDENCE OVER THE PROJECT SPECIFICATIONS. REFER TO THE SPECIFICATIONS FOR SPECIFIC INFORMATION NOT COVERED IN THIS PREPARATION. THIS INFORMATION WAS TAKEN FROM A GEOTECHNICAL REPORT PREPARED BY TERRACON DATED MARCH 16, 2012 (GEOTECHNICAL REPORT IS FOR INFORMATION ONLY AND IS NOT A CONSTRUCTION SPECIFICATION).