HomeMy WebLinkAboutRS_GeotechReport_181031.pdfRevised Geotechnical Engineering
Report
Cedar River Apartments
Renton, Washington
October 31, 2018
Terracon Project No. 81175025
Prepared for:
SRM Renton, LLC
Kirkland, Washington
Prepared by:
Terracon Consultants, Inc.
Mountlake Terrace, Washington
TABLE OF CONTENTS
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Page
EXECUTIVE SUMMARY ............................................................................................................. i
1.0 INTRODUCTION ............................................................................................................. 1
2.0 PROJECT INFORMATION ............................................................................................. 1
2.1 Site Location and Description............................................................................... 1
2.2 Project Description ............................................................................................... 2
3.0 SUBSURFACE CONDITIONS ........................................................................................ 2
3.1 Geology ............................................................................................................... 2
3.2 Typical Profile ...................................................................................................... 3
3.2.1 Stratum 1 - Fill .......................................................................................... 3
3.2.2 Stratum 2 – Alluvium, Loose to Medium Dense ........................................ 4
3.2.3 Stratum 3 – Alluvium, Medium Dense to Very Dense ............................... 4
3.3 Groundwater ........................................................................................................ 4
3.4 Critical Areas ....................................................................................................... 5
3.4.1 Steep-Slope Critical Area ......................................................................... 5
4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION ...................................... 6
4.1 Geotechnical Considerations ............................................................................... 6
4.2 Earthwork............................................................................................................. 7
4.2.1 Site Preparation........................................................................................ 8
4.2.2 Subgrade Preparation .............................................................................. 8
4.2.3 Temporary Cut Slopes .............................................................................. 9
4.2.4 Material Requirements ............................................................................. 9
4.2.5 Compaction Requirements ..................................................................... 10
4.2.6 Utility Trench Backfill .............................................................................. 10
4.2.7 Grading and Drainage ............................................................................ 11
4.2.8 Earthwork Construction Considerations .................................................. 11
4.2.9 Wet Weather Earthwork ......................................................................... 11
4.2.10 Permanent Slopes .................................................................................. 12
4.3 Foundations ....................................................................................................... 12
4.3.1 Ground Improvement with Aggregate piers ............................................ 13
4.3.2 Foundation Design Recommendations ................................................... 13
4.4 Floor Slabs......................................................................................................... 14
4.4.1 Floor Slab Design Recommendations .................................................... 14
4.4.2 Floor Slab Construction Considerations.................................................. 14
4.5 Seismic Considerations...................................................................................... 15
4.6 Lateral Earth Pressures ..................................................................................... 16
4.7 Pavements ......................................................................................................... 19
4.7.1 Subgrade Preparation ............................................................................ 19
4.7.2 Design Considerations ........................................................................... 19
4.7.3 Asphaltic Cement Concrete Thickness ................................................... 21
4.7.4 Pavement Drainage ................................................................................ 22
4.7.5 Pavement Maintenance .......................................................................... 22
4.8 Settling Pond Reconnaissance .......................................................................... 22
5.0 GENERAL COMMENTS ............................................................................................... 23
TABLE OF CONTENTS (continued)
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APPENDIX A – FIELD EXPLORATION
Exhibit A-1 Vicinity Map
Exhibit A-2 Exploration Plan
Exhibit A-3 Settling Pond Summary
Exhibit A-4 Field Exploration Description
Exhibit A-5 to A-11 Boring Logs B-1 to B-7
Exhibit A-12 to A-23 Test Pit Logs TP-1 to TP-12
APPENDIX B – LABORATORY TESTING
Exhibit B-1 Laboratory Testing Description
Exhibit B-2 Grain Size Analysis Results
Exhibit B-3 Moisture-Density Relationship
Exhibit B-4 California Bearing Ratio
APPENDIX C – SUPPORTING DOCUMENTS
Exhibit C-1 General Notes
Exhibit C-2 Unified Soil Classification System
Exhibit C-3 Historical Monitoring Well Data
Exhibit C-4 USGS Seismic Design Maps Report
Exhibit C-5 WSLiq Outputs
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October 31, 2018 Terracon Project No. 81175025
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EXECUTIVE SUMMARY
A geotechnical exploration program has been performed for the proposed project located at 1915
Maple Valley Highway in Renton, Washington. Terracon’s geotechnical scope of services
included the advancement of seven (7) geotechnical borings and twelve (12) test pits. The site
appears suitable for the proposed construction based upon geotechnical conditions encountered
in the explorations and our current understanding of the proposed development, contingent on
meeting the recommendations provided in this report. The following geotechnical considerations
have been identified as being significant as related to the design and construction of the proposed
facilities:
n Existing fill was encountered at all exploration locations. The fill soils were found to be variable
in composition, depth, and density. In the western region of the site, concrete-like soils were
encountered and are suspected to be hardened through leaching of wet cement as part of past
site usage. Specialty earth-moving equipment may be necessary to meet planned elevations for
foundations and utilities within this, and other, region(s) of the site.
n Groundwater was encountered in all borings and was observed between 11 and 24 feet. The
groundwater depths observed are consistent with historical data from previous interim action
measures. The ground water table was generally observed within a loose to medium dense
alluvium stratum.
n Liquefiable soils were encountered between 18 and 32 feet below ground surface (bgs).
Liquefaction-induced settlements are estimated to range from 2 to 6 inches. Horizontal
displacements from lateral spreading are estimate to range from ½ to 3 feet.
n Static settlement of the existing fill and post-liquefaction displacements are expected to
exceed those tolerable by typical, residential structures founded on conventional spread
footings. Therefore, we recommend ground improvement using aggregate piers for all
buildings. We also recommend mat foundation support for buildings located within 250 feet of
the river to meet the life-safety performance objective for seismic design. Other ground
improvement and foundation support options may be considered after discussion with the
structural engineer and establishment of tolerable displacements.
n For planning purposes, we recommend an allowable bearing pressure of 4,000 psf for shallow
foundations (i.e., footings and mats) constructed over aggregate piers. We also recommend
a subgrade modulus values of 250 pci. Recommendations for site and subgrade preparation,
earthwork, fill placement and compaction, drainage, and temporary and permanent slope cuts
are included.
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n Close monitoring of the construction operations discussed herein will be critical in achieving
the design subgrade support. We therefore recommend that the Terracon be retained to
monitor this portion of the work.
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
section titled GENERAL COMMENTS should be read for an understanding of the report
limitations.
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REVISED GEOTECHNICAL ENGINEERING REPORT
Cedar River Apartments
Renton, Washington
Terracon Project No. 81175025
October 31, 2018
1.0 INTRODUCTION
Terracon Consultants, Inc. (Terracon) is pleased to present the results of our geotechnical
engineering services for the proposed Cedar River Apartments project. The site is located at 1915
Maple Valley Highway, Renton, Washington. A log of the site exploration along with a site location
map and exploration plan are included in Appendix A of this report.
The purpose of these services is to provide information and geotechnical engineering
recommendations relative to:
n subsurface soil conditions n slab design and construction
n groundwater conditions n seismic considerations
n earthwork
n foundation design and construction
n pavement design recommendations
n settling pond characterization
2.0 PROJECT INFORMATION
2.1 Site Location and Description
Item Description
Location
Approximately 7-acre open lot near 1915 SE Maple Valley Hwy lying
between the highway and Cedar River in Renton, Washington.
Latitude: 47.4801 Longitude: -122.1939
Existing improvements
The site is currently undeveloped and is used as vehicular and
equipment storage. At the south end of the site, adjacent to the Cedar
River exists several settling ponds and an infiltration basin.
Current ground cover
Little to no vegetation within the site boundaries. Several large pine
trees exist in the northwest corner. Sparse, light vegetation along the
perimeter.
Existing topography
Gently sloping from Maple Valley Hwy to the Cedar River. A steeper,
short grade change exists at the eastern third of the site paralleling
the southern boundary and resembling an old roadbed.
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2.2 Project Description
Item Description
Site Layout
Refer to the Exploration Plan (Exhibit A-2 in Appendix A). The
apartment structures (Buildings A and B) will be located along the
river, setback approximately 100 feet from the river’s edge. The site
plan includes a parking area for each building located within the
middle wing. Courtyards are located within the furthest wings of each
building as well as between the buildings. The commercial
development is located at the approximate middle of the
northeastern boundary. Paved access routes and parking stalls are
proposed along northern portion of the site.
Structures
Two, five-story, multi-wing apartment structures (Building A and B)
with a two story, lobby area betweeh the buildings. A retail pad is
proposed for the wst building. As presented in the site plan, the lobby
area is considered part of Building A. The total footprint of Buildings
A and B is 149,189 square feet and the commercial building pad is
roughly 70,000 square feet.
Site Grading
The apartment buildings are anticipated to be near the approximate
existing ground elevation at each building’s respective location.
Grading will be minimal to produce level grades at the building
locations. The proposed finish floor elevation for Level 1 is 52.0 feet.
Cut and fill slopes
The settling ponds along the southern boundary adjacent to the river
will be demolished and the shoreline restored to a near-natural state.
Temporary cut slopes are assumed to be used to accomplish the
demolition work.
3.0 SUBSURFACE CONDITIONS
3.1 Geology
The site is located within the Cedar River basin near Renton, Washington. The surficial geology
of site is shown as Qac – Quaternary, Cedar River alluvium – when viewed using the Washington
State Department of Natural Resources online application. The soil units observed were
consistent with the geologic mapped units and were predominantly alluvial deposits overlain by a
relatively thin layer of fill.
Based on published data and conditions that we have observed during advancement of the
subsurface exploration at the site, subsurface conditions include a relatively shallow unit of loose
to very dense existing fill, loose to medium dense sand of variable silt and gravel content, and
medium dense to very dense sand and gravel alluvium. A total of seven (7) soil borings and 12
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test pits were performed from 35 to 61½-feet below ground surface (bgs) and 12 test pits were
performed from 4 to 10 feet bgs (See Exhibit A-2).
3.2 Typical Profile
Based on the results of the borings, subsurface conditions on the project site can be generalized
as follows:
Stratum
Approximate Depth to
Bottom of Stratum
(feet)
Material Description Consistency/
Density
1 21 to 18 Uncontrolled fill 2 of primarily sand with
variable silt and gravel content (FILL)
Loose to Very
Dense
2 13 to 29 Primarily sand and gravel with variable silt
content (Alluvium)
Loose to Medium
Dense
3 Undetermined 3 Gravel with variable sand and silt content
and interbedded sand lenses (Alluvium)
Medium Dense to
Very Dense
1. The site is surfaced with roughly 1 to 2 feet of gravel ballast and quarry spalls
2. Uncontrolled fill is material that was placed without moisture and density control. This material is
typically variable in composition, consistency, density, moisture, and depth. It was difficult to discern
between native soil and uncontrolled fill due to the disturbed sampling techniques and variation in
color and composition.
3. All borings were terminated within this stratum.
Conditions encountered at each boring location are indicated on the individual boring logs.
Stratification boundaries on the boring logs represent the approximate location of changes in soil
types; in situ, the transition between materials may be gradual. Details for each of the borings can
be found on the boring logs in Appendix A of this report. Laboratory tests consisted of index testing
to verify the USCS classifications were conducted on selected soil samples. Test results are
presented in Appendix B.
3.2.1 Stratum 1 - Fill
The fill was characterized through test pit and soil boring explorations. The stratum is generally
overlain by 1 to 2 feet of gravel ballast and smaller, 4 to 6 inch quarry spalls. The soils are primarily
silty sandy with varying silt and gravel content. Anthropogenic debris was observed in most of the
test pits and includes concrete, brick, wood, plastics, metal, and fabric. Additionally, several test
pits experienced significant cobble content. TP-2 experienced up to 7 feet of material consisting
of 20 to 50% rounded cobbles. Significant cobble content was also observed in TP-5, TP-6, and
TP-7. High cobble contents were not encountered at other exploration locations
Hard, concrete-like material was experienced in the upper 4 to 18 feet of the western portion of
the site that includes B-2 and B-3 and TP7, TP8, and TP-9. Samples recovered at this depth
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range exhibit properties that are similar to weak concrete. We understand that a cement plant
was previously in operation at the site. Leaching of wet cement through the ground and hardening
likely created this concrete-like zone in this region of the site. Although the ground is concrete-
like, drilling augers were advanced through the material. For test pit explorations, this portion of
the site and was unable to be excavated with a mini-excavator and test pits were terminated at
the contact with the concrete-like material.
An approximate 10-inch thick concrete slab was encountered at 2.5 to 5.0 feet bgs in TPs 7, 8, 9,
11, and 12. The slab was reinforced and difficult to excavate with the mini-excavator.
3.2.2 Stratum 2 – Alluvium, Loose to Medium Dense
The alluvium was characterized through test pit and soil boring explorations. Generally, the
stratum is overlain by 4 to 18 feet of existing fill and varies from loose to medium dense with
occasional dense zones. The soils are primarily silty sand with varying gravel and silt contents. In
several borings, the unit was observed to be interbedded with thin sandy silt seams (typically 1 to
2 inch) and gravel lenses. The groundwater table was generally observed within this unit.
3.2.3 Stratum 3 – Alluvium, Medium Dense to Very Dense
Soil boring explorations characterized the medium dense to very dense alluvium categorized as
Stratum 3. This stratum is generally overlain by Stratum 2 between depths of 11½ and 29 feet.
The unit is predominately composed of subangular to subrounded gravel of various sizes. In
addition, sand and silt contents differed between boring locations at depth. Medium to coarse-
grained sand seams are interbedded within the unit, along with 1 to 2 inch silt seams. Finally,
organic debris was observed in B-2 at a depth of 29 feet., which included wood fragments.
Due to the high gravel content and depth of this unit, hard drilling was observed in the majority of
the boreholes. The drilling rig typically experienced intermittent zones of hard drilling between
depths of 27 and 60 feet. Sand lenses interbedded within the stratum were often observed to be
in a looser state as indicated by smoother drilling and lower in situ standard penetration test (SPT)
results.
3.3 Groundwater
Groundwater seepage was encountered in all seven borings and was observed in four existing
groundwater monitoring wells. The monitoring well locations, installed by others, are shown on
Exhibit A-2. The depth to groundwater in the Terracon borings ranged from 11 to 24 feet bgs at
the time of the investigation. Historical data from themonitoring wells suggests that the depth to
groundwater could be as shallow as 11.1 feet bgs and trends deeper to the west. We compiled
the historical monitoring well data and present the results in Appendix C
Groundwater level fluctuations occur due to seasonal variations in the amount of rainfall, runoff,
river elevations, and other factors not evident at the time the borings were performed. In addition,
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perched water can develop over low-permeability soil. Therefore, groundwater levels during
construction or at other times in the life of the structure may be higher or lower than the levels
indicated on the boring logs. The possibility of groundwater level fluctuations should be
considered when developing the design and construction plans for the project.
3.4 Critical Areas
The site was reviewed for geologic hazards using the City of Renton online GIS mapping tool
(http://rp.rentonwa.gov/HTML5Public/Index.HTML?viewer=CORMaps). Several areas within the
site are mapped as steep slope critical areas include the portion of the site that is nearest to the
river. Landslide hazards, which are commonly co-mapped with steep-slope areas are only
observed north of the site, across and paralleling Maple Valley Highway. Additionally, the site is
within a seismic hazard mapped area. This critical areas section is limited to the mapped steep-
slope slope critical area. An assessment of seismic hazards is presented in Section 4.5 Seismic
Considerations. Landslide hazards are discussed as part of the report but may want to be
considered given that the site is primarly accessed from Maple Valley Highway.
3.4.1 Steep-Slope Critical Area
The steep slopes mapped within the site are primarily classified as Sensitive (i.e. grade of 40
percent or less); however, the westernmost end of the site is classified as Protected (i.e. grade of
40 to 90 percent). A discussion of the Sensitive and Protected areas as it relates to the site
development is presented below:
Sensitive:The planned development includes a 100-foot buffer setback from the Cedar River.
Areas beyond this buffer will largerly be leveled during site grading to support the proposed
development. These areas are generally surround by level to gently sloping ground and do not
appear to present a hazard.
Slope areas along the Cedar River are generally present due to natural stream processes as the
river has eroded and steepened the upland soils. These sloped areas have been considered as
part of the seismic hazard assessment presented later in this report as lateral spreading potential
is influenced by the presence of steep-slopes. Recommendations to mitigate the potential hazard
are presented later in the report.
Protected: Based on our review of the proposed site development and site grades, the
westernmost end of the Building B appears to be roughly 50 and 100 feet east and north,
respectively, of the nearest extent of the protected area. The development does not appear to
impact this slope area due to the buffer setback from the Cedar River.
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4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION
4.1 Geotechnical Considerations
Based on the results of the subsurface exploration, laboratory testing, and our analyses, the site
is subject to free-field, vertical and lateral displacements during a design-level seismic event of
up to ½ foot and 3 feet, respectively. Liquefiable soils primarily exist within Stratum 2, loose to
medium dense alluvium, and are observed in discontinuous layers within Stratum 3, medium
dense to very dense alluvium. Furthermore, the variability of the fill unit observed through the test
pits and borings demonstrates the potential for erratic settlements under static conditions.
Mitigation of the seismic-induced vertical and lateral displacements can be accomplished through
ground improvement or use of deep foundations. Ground improvement options such as jet-
grouting and deep soil-cement mixing densify the ground by means of mixing soil and cement to
produce concrete-like columns. These ground improvement options may be considered to
construct a buttress adjacent to the river to mitigate lateral spreading. Deep foundations such as
driven piles, augercast piles, and drilled shafts would transfer the structure’s loads through the
weaker, liquefiable unit to competent soils, but the design is generally controlled by horizontal
loading from lateral spreading. Lateral resistance is accomplished though flexural bending of the
piles which can result in relatively large pile diameters.
The mitigation options of ground improvement and deep foundations mentioned above are
generally expensive and may not be the most cost-effective solution. Assuming the structures can
be designed to tolerate some lateral displacements while satisfying the seismic performance
objective of life-safety, we recommend ground improvement with aggregate piers. Aggregate
piers are generally a less expensive ground improvement method and are commonly used to
mitigate excessive settlements. However, aggregate piers do not mitigate lateral spreading.
Therefore, we recommend supporting buildings within 250 feet of the river on mat foundations
over the aggregate piers. The depth of the aggregate piers should extend through the loose to
medium dense alluvium, which is typically 25 to 32 feet bgs. Ground improvement should extend
outside the building footprint by 5 feet or least 10 percent of the building footprint, whichever is
greater. A specialty contractor should be consulted for design of the ground improvement system
and the structural engineer should be consulted to provide the tolerable post-liquefaction
displacements.
n Existing uncontrolled fill is typically recommended to be removed and replaced with structural
fill; however, the inclusion of aggregate piers as a ground improvement solution eliminates
the need for fill removal. Anthropogenic materials and other deleterious objects encountered
during foundation grading and installation of aggregate piers may require overexcavation and
replacement with structural fill. It is recommended that Terracon be retained during
construction to observe and identify such materials
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n Soft subgrade potential exists for the siltier soils we observed in the eastern portion of the site.
The siltier soils are compressible and may pose challenges for construction of utilities,
trenches, and other improvements. The construction of aggregate piers will largely mitigate
the settlement potential beneath the structure but may require a dense aggregate pier field for
lateral resistance due to the generally weaker nature of silty soils. The extents of the siltier
soils within the building footprint are not known at this time and will require monitoring and
observation by a geotechnical engineer during construction to assess the extent.
n Cement-hardened ground described in Section 3.2.1 may present challenges with respect to
construction of the ground improvement system, foundation grading, and installation of
utilities. Specialty equipment may be required to excavation the concrete-like ground. For
purposes of communicating the potential extend of the cement-hardened ground, a
conceptual delineation of the hardened ground is present on Exhibit A-2.
n The settling ponds along the approximate middle of the southern boundary should be
demolished and excavated to native soil. Dewatering of the pond basins and removal of
sediments at the bottom of the pond should be accomplished prior to backfilling.
Recommendations for temporary slope cuts and placement and compaction of fill is provided
herein.
Specific conclusions and recommendations regarding these geotechnical considerations, as well
as other geotechnical aspects of design and construction of foundation systems and other
earthwork related phases of the project are outlined in the following sections. The
recommendations contained in this report are based upon the results of field and laboratory
testing (presented in Appendices A and B), engineering analyses, and our current understanding
of the proposed project. ASTM and Washington State Department of Transportation (WSDOT)
specification codes cited herein respectively refer to the current manual published by the
American Society for Testing & Materials and the current edition of the Standard Specifications
for Road, Bridge, and Municipal Construction, (M41-12).
4.2 Earthwork
Based on the subsurface conditions encountered in our exploration, we expect that all of the on-
site soils shallower than about 4 feet bgs and within the limits of construction can be removed
with conventional excavation equipment. For excavations deeper than 4 feet, particularly in the
western region of the site, specialty equipment maybe required for removal of the concrete-like
soil condition that exists. Cobbles were observed in our explorations and te contractor should be
prepared to deal with cobbles and boulders. Recommendations for site preparation, structural fill,
and permanent slopes are presented below
Earthwork on the project should be observed and evaluated by Terracon. The evaluation of
earthwork should include observation and testing of engineered fill, subgrade preparation, ground
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improvement and/or deep foundation installation, and other geotechnical conditions exposed
during the construction of the project.
4.2.1 Site Preparation
Prior to equipment arriving onsite, clearing and grading limits should be established and marked.
Silt fences should be constructed along the downslope side of all areas planned for clearing and
grading. Preparation for site grading and construction should begin with procedures intended to
control surface water runoff. The site naturally grades toward the Cedar River with drainage
features to channel water to the settling ponds. To the extent possible, the contractor should
complete work to use the natural drainage of the site to reduce erosion and runoff. The site is
largely free of vegetation presenting a relatively high susceptible to erosion by flowing water. We
anticipate that adequate surface water control during wet weather and wet site conditions can be
accomplished through supplementing existing drainage feature with shallow ditches and sumps
and pumps as needed.
Stripping efforts should include removal of vegetation, organic materials, and any deleterious
debris. The majority of the site is surfaced with gravel ballast and quarry spalls. Salvaging of the
upper 2 feet of materials may be desirable for use of these materials for structural purposes
elsewhere onsite. It appears that up to about ½-foot of stripping will be necessary in some areas
with light vegetation. Greater depths of stripping and grubbing may be necessary in areas with
thick vegetation and tree roots. Stripped materials that include significant organic content are not
suitable for reuse as structural fill. Site disturbance beyond the work area should be limited to
reduce the potential for erosion and off-site sediment transport. Disturbance of existing vegetation
and soil structure on slopes should be avoided if at all practical; if disturbance is necessary, the
area should be restored with landscaping, or paving with stormwater diversion as soon as
possible.
4.2.2 Subgrade Preparation
Areas that are stripped or excavated to the design subgrade elevation, or that are to receive
structural fill, should be proofrolled with heavy rubber-tired construction equipment (e.g. loaded
dump truck). Any soft, loose, or otherwise unsuitable areas identified during proofrolling should
be recompacted if practical or removed and replaced with structural fill. We recommend that
proofrolling of the subgrade be observed by a representative of our firm to assess the adequacy
of the subgrade conditions and identify areas needing remedial work. We recommend that this
procedure not be performed during wet weather. During wet conditions, systematic probing should
be used to evaluate the subgrade.
In the event that overexcavation is necessary in order to reach suitable, subgrade soils we
recommend that Terracon be retained to oversee excavation efforts to verify expected conditions.
All subgrades that have been prepared should be observed by a Terracon representative prior to
the placement of foundation elements or structural fill. If structural fill is used to reestablish desired
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grades, it should be placed over an approved subgrade and in accordance with the specifications
and recommendations provided in the following sections.
4.2.3 Temporary Cut Slopes
We anticipate that temporary open cuts and/or trenches will be utilized during construction of the
project, particularly on the upslope side of foundations and for decommissioning of the settling
ponds. Temporary slope stability is a function of many factors, including the following:
n The presence and abundance of groundwater
n The type and density of the various soil strata
n The depth of cut
n Surcharge loading adjacent to the excavation
n The length of time the excavation remains open
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 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. It may be necessary to drape temporary
slopes with plastic or to otherwise protect the slopes from the elements and minimize sloughing
and erosion. We do not recommend vertical slopes or cuts deeper than 4 feet if worker access is
necessary. The contractor should reference Chapter 296-155, Part N, Excavation Trenching and
Shoring, of the Washington Administrative Code (WAC). The cuts should be adequately sloped
or supported to prevent injury to personnel from local sloughing and spalling. The excavations
should conform to applicable Federal, State, and local regulations.
4.2.4 Material Requirements
Compacted structural fill should meet the following material property requirements:
Fill Type Recommended Materials Acceptable Location for Placement
Structural Fill
9-03.12(1)A Gravel Backfill for
Foundations Class A1
9-03.9(1)Ballast
9-03.9(3)Crushed Surfacing
Base Course1
Existing Gravel Ballast and
Quarry Spalls2
Beneath and adjacent to structural slabs and
foundations
Common Fill
Section 9-03.14(3)Common
Borrow1
Native silty sand, gravelly
sand, and silty gravel 3
Backfilling of settling ponds, utility trenches,
general site leveling, landscaping
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Fill Type Recommended Materials Acceptable Location for Placement
1. WSDOT Standard Specifications
2. Materials were observed in the upper 2 feet and should be stockpiled separately from topsoil
and other organic-rich soils.
3. Fines content of near surface native silty sand make this material moisture sensitive and
therefore unsuitable for use during periods of wet weather.
4.2.5 Compaction Requirements
Item Description
Fill Lift Thickness
8 inches or less in loose thickness when heavy, self-
propelled compaction equipment is used
4 inches in loose thickness when hand-guided equipment
(i.e. jumping jack or plate compactor) is used
Minimum Compaction Requirements
for Structural Fill
Minimum 95% of the material’s maximum modified Proctor
dry density (ASTM D 1557)
Minimum Compaction Requirements
for Common Fill
Minimum 90% of the material’s maximum modified Proctor
dry density (ASTM D 1557)
Moisture Content – Granular Material Workable moisture levels 1
1. Typically within 2% of optimum
4.2.6 Utility Trench Backfill
Utility trenching should conform to all applicable federal, state, and local regulations, such as
OSHA and WISHA, for open excavations.
All trenches should be wide enough to allow for compaction around the haunches of the pipe, or
material such as pea gravel (provided this is allowed by the pipe manufacturer) should be used
below the spring line of the pipes to eliminate the need for mechanical compaction in this portion
of the trenches. We recommend that utility trench excavations be completed using a smooth
excavation bucket (without teeth) to reduce the potential for subgrade disturbance. If water is
encountered in the excavations, it should be removed prior to fill placement.
Materials, placement and compaction of utility trench backfill should be in accordance with the
recommendations presented in Sections 4.2.2 to 4.2.5 of this report. In our opinion, the initial lift
thickness should not exceed one foot unless recommended by the manufacturer to protect utilities
from damage by compacting equipment. Light, hand-operated compaction equipment in
conjunction with thinner fill lift thicknesses may be utilized on backfill placed above utilities if
damage resulting from heavier compaction equipment is of concern.
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Flexible connections for utilities that pass through building foundations are recommended to
reduce potential stress associated with differential settlement that may occur between the building
foundation and the improvements located outside of the building footprint.
4.2.7 Grading and Drainage
The site is naturally contoured to drain toward the river. Site grades should be established such
that surface water is directed away from foundation and pavement subgrades to prevent an
increase in the water content of the soils. Adequate positive drainage diverting water from
structures, open cuts, and slopes should be established to prevent erosion, ground loss, and
instability.
Gutters and downspouts should be routed into tightline pipes that discharge either directly into a
municipal storm drain or to an alternative drainage facility. Splash-blocks should also be
considered below hose bibs and water spigots.
4.2.8 Earthwork Construction Considerations
It is anticipated that excavations for the proposed construction can largely be accomplished with
conventional, heavy-duty, earthmoving equipment. The western portion of the site that has been
cement-hardened below about 4 feet bgs may require specialty equipment. Additionally, in the
eastern portion near B-6, the earthwork contractor should anticipate encountering soils that are
highly sensitive to changes in moisture and disturbance that could potentially result in unstable or
inadequate working pad and/or foundation subgrade conditions. In addition, cobbles, boulders,
and construction debris (e.g., concrete, and a buried concrete slab were all observed in the test
pits and should be anticipated during construction. Note that several test pits met refusal on
concrete-like material.
If earthwork takes place during freezing conditions, we recommend that the exposed subgrade
be allowed to thaw and be re-compacted prior to placing subsequent lifts of structural fill.
Alternatively, the frozen soil could be scraped off and wasted to expose unfrozen soil.
The contractor is responsible for designing and constructing stable, temporary excavations as
required to maintain stability of both the excavation sides and bottom. Excavations should be
sloped or shored in the interest of safety following local and federal regulations, including current
OSHA excavation and trench safety standards.
4.2.9 Wet Weather Earthwork
The near surface, existing fill has variable fines content based on our visual observations and lab
testing and is considered moisture sensitive. The soil has a low to moderate erosion potential in-
place and may be transported by running water. Therefore, silt fences and other measures will be
necessary to control erosion and sediment transport during construction.
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The suitability of soils used for structural fill depends primarily on their grain-size distribution and
moisture content when they are placed. As the fines content (that soil fraction passing the U.S.
No. 200 Sieve) increases, soils become more sensitive to small changes in moisture content.
Soils containing more than about 5 percent fines (by weight) cannot be consistently compacted
to a firm, unyielding condition when the moisture content is more than 2 percentage points above
or below optimum. Optimum moisture content is the moisture content at which the maximum dry
density for the material is achieved in the laboratory following ASTM procedures.
If inclement weather or in situ soil moisture content prevents the use of on-site material as
structural fill, we recommend the use of import granular fill containing less than 5 percent by
weight passing the U.S. No. 200 sieve, based on the fraction passing the U.S. No. 4 sieve.
We recommend that all stockpiled soils for use as structural fill be protected with polyethylene
sheeting anchored to withstand local wind conditions.
4.2.10 Permanent Slopes
For fill areas prepared as recommended in Section 4.2.4 and 4.2.5 and on subgrade prepared as
recommended in Section 4.2.2, we recommend the following maximum permanent slope
inclinations relative to a horizontal reference plane:
n Structural Fill: 26.5 degrees (2H:1V)
n Common Fill: 18.5 degrees (3H:1V)
We recommend that permanent cut-slopes be laid back for long-term stability and to reduce the
potential for long-term erosion. We recommend that the shoreline along the southern boundary
of the property have a maximum permanent slope inclination of 3H:1V. Unconsolidated native
soils and existing fill soils observed on site are also recommended to have a maximum permanent
slope inclination of 3H:1V and a maximum height of 4 feet. We are available to provide more
detailed recommendations for permanent slopes that exceed 4 feet in height.
4.3 Foundations
It is our opinion that the buildings can be founded on a combination of aggregate piers and mat
foundations. For buildings located within 250 feet of the river, we recommend mat foundation
support, and for buildings setback further than 250 feet, we recommend support with spread and
continuous footings. For purposes of this report, we assume the structures can be designed to
tolerate some lateral displacement. We recommend that the structal engineer and Terracon work
together to establish this amount with the owner. Without mitigation, potentially liquefiable soils
are estimated to result in free field, vertical and lateral displacements of up to ½-foot and 3 feet,
respectively, for the design-level seismic event. As noted in Section 4.5, we recommend the
structure be designed for a Site Class F designation. Design recommendations for shallow
foundations are presented in the following paragraphs.
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4.3.1 Ground Improvement with Aggregate Piers
Implementation of aggregate piers is a method of ground improvement that offers a practical and
effective alternative to deep soil mixing and means to circumvent the use of deep foundations for
structural support. Aggregate piers are columns of crushed stone that, when configured in groups,
can provide a significant increase in the density and overall strength of the surrounding soil mass.
The increase in density is partly a result of the lateral displacement of the soil that occurs within
the subsurface during installation. Relative spacing of the aggregate piers is typically specified by
a specialty contractor that accounts for the anticipated building loads in order to determine the
level of improvement that is deemed necessary to sustain the required loading. As a general rule
of thumb we recommend that aggregate piers extend approximately 5 feet or 10 percent of the
building footprint, whichever is greater, beyond all building limits for adequate support of the
structures. For planning purposes of mat foundation sizes, we recommend an allowable bearing
pressure of 4,000 psf. A soil subgrade modulus of 250 pci can be assumed for point loads and 60
pci for distributed loads. The design bearing pressure and subgrade modulus should be
determined by the ground improvement contractor and reviewed by Terracon.
4.3.2 Foundation Design Recommendations
Description Column/Mat Wall/Mat
Net allowable bearing pressure 1
n Ground improvement with aggregate
piers 4,000 psf 4,000 psf
Minimum dimensions 30 inches/Not
applicable
18 inches/Not
applicable
Minimum embedment below finished grade 2 18 inches 18 inches
Approximate static total settlement from
foundation loads <1 inch <1 inch
Estimated static differential settlement from
foundation loads
<¾ inch between
columns <¾ inch over 40 feet
Ultimate passive pressure 3
n Compacted structural fill or improved
existing fill 350 pcf, equivalent fluid density
Ultimate coefficient of sliding friction 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 and should be confirmed by the
ground improvement contractor. Assumes any unsuitable soft soils, if encountered, will be undercut
and replaced with compacted structural fill. Based upon a minimum Factor of Safety of 3.
2. For frost protection and to reduce the effects of seasonal moisture variations in the subgrade soils.
For perimeter footing and footings beneath unheated areas.
3. Passive resistance in the upper 12 inches of the soil profile should be neglected.
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4.4 Floor Slabs
In our opinion, the structures farther than 250 feet from the shoreline are subject to primarily
vertical displacements from liquefaction and/or the potential for erratic static settlement from
existing fill. The structures will primarily be lightly loaded, retail and commercial buildings and are
suitable for conventional, Portland Cement Concrete (PCC) slab-on-grade floor slabs provided
the existing fill is improved with aggregate piers. Design recommendations are presented in the
following table and paragraphs.
4.4.1 Floor Slab Design Recommendations
DESCRIPTION VALUE
Interior floor system Slab-on-grade concrete.
Floor slab subgrade support Existing fill improved with aggregate piers in accordance with
sections 4.2.2, 4.2.4, and 4.2.5 of this report.
Base course 1
4-inch compacted layer of free draining, uniform gravel or coarse
sand containing less than 5 percent passing the No. 200 sieve
by weight.
1. The base course serves as a capillary break layer, a drainage layer, a leveling layer, and a bearing
layer.
We recommend subgrades be maintained at the proper moisture condition until floor slabs are
constructed. If the subgrade should become disturbed prior to construction of floor slabs, the
affected material should be removed or the materials scarified, moistened, and recompacted.
Upon completion of grading operations in the building areas, care should be taken to maintain the
recommended subgrade moisture content and density prior to construction of the building floor
slabs.
Where appropriate, saw-cut control joints should be placed in the slab to help control the location
and extent of cracking. For additional recommendations refer to the ACI Design Manual.
The use of a vapor retarder or barrier should be considered beneath concrete slab-on-grade floors
that will be covered with wood, tile, carpet or other moisture-sensitive or impervious coverings, or
when the slab will support equipment sensitive to moisture. If penetrations through the barrier are
required, that portion of the barrier should be replaced prior to construction of the slab above.
When conditions warrant the use of a vapor retarder, the slab designer and slab contractor should
refer to ACI 302 and ACI 360 for procedures and cautions regarding the use and placement of a
vapor retarder/barrier.
4.4.2 Floor Slab Construction Considerations
After excavation to subgrade elevation, the base of the excavation is frequently disturbed or
altered due to utility excavations, construction traffic, desiccation, or rainfall. As a result, the slab-
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on-grade subgrade may become unsuitable for floor slab support. At the time of capillary break
placement, the subgrade should be evaluated by conducting a proof roll to verify a firm and non-
yielding surface. Proof-rolling should be completed using heavy equipment under the observation
of Terracon. This observer will assess the subgrade conditions prior to capillary break placement.
Areas where loose, soft, or disturbed surface soils are observed should be compacted or removed
and replaced to the depth of the disturbance as recommended for structural fill.
4.5 Seismic Considerations
We assume the site will be designed to conform to the 2015 International Building Code (IBC)
and ASCE 7-10 which is based on designing for an event with a 2 percent chance of exceedance
in 50 years. The following discusses the soil site class and seismic hazard potential at the site:
Code Used Site Classification
2015 International Building Code (IBC) and 2010
ASCE 7 1 F 2
Site Latitude 47.48012°N
Site Longitude 122.19392°W
Ss – Short Period Spectral Acceleration for Site
Class B 1.425 g
S1 – 1-Second Period Spectral Acceleration for
Site Class B 0.533 g
Fa – Short Period Site Coefficient 3 1.0
Fv – 1-Second Period Site Coefficient 3 1.5
1. The 2015 International Building Code and 2010 ASCE 7 document indicates that the seismic site
classification is based on the average soil and bedrock properties in the top 100 feet. The current
scope does not include a 100-foot soil profile determination. This seismic site class definition
considers that soils encountered at depth in our boring continue below the termination depth.
Additional exploration to deeper depths would be required to confirm the conditions below the current
depth of exploration.
2. Note: Site Class F applies to any profile having (1) soils vulnerable to potential failure or collapse
under seismic loading such as liquefiable soils, quick and highly sensitive clays and collapsible
weakly cemented soils, (2) at least 10 feet of peats and/or highly organic clays, (3) at least 25 feet
of very high plasticity clays or (4) at least 120 feet of soft to medium stiff clays.
3. ASCE 7-10 allows site coefficients Fa and Fy to be determined assuming that liquefaction does not
occur for structures with fundamental periods of vibration less than 0.5 second. Based on the results
of the exploration program, Site Class D may be used to determine the values of F a and Fv. The
fundamental period of vibration for the structure should be verified by the structural engineer.
The hazard of damage from onsite fault rupture appears to be low based on review of the USGS
Earthquake Hazards Program Quaternary Faults and Folds Database available online
(http://earthquake.usgs.gov/hazards/qfaults/map) accessed on March 7, 2017. The closest
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mapped fault is the Seattle fault zone. The closest estimation of the trace of this fault lies
approximately 3 miles to the north.
Liquefaction is the phenomenon where saturated soils develop high pore-water pressures during
seismic shaking and lose their strength characteristics. This phenomenon generally occurs in
areas of high seismicity, where groundwater is shallow and loose granular soils or relatively non-
plastic fine-grained soils are present. Based on the site geology and subsurface groundwater
conditions, the hazard of liquefaction of the site soils is moderate to high for this site during a design
level earthquake and is most likely to trigger between 18 and 32 feet below the ground surface. The
site is gently sloping toward the Cedar River with a grade between 2 and 5 percent. Due to the
absence of bathymetric data, the river bed is assumed to be at an elevation of 27 feet. Near the river,
the topographic relief between the top of bank and the river bed is estimated to be an average of
about 16 feet and creates a free-face ratio of up to 22 percent at B-5.. The risk of lateral spreading
is low to moderate while the risk of flow sliding is relatively low, largely due to the planned setback.
Liquefaction and lateral spreading were evalauted using WSLiq software developed by Prof. Steven
L. Kramer at the University of Washington (http://faculty.washington.edu/kramer/WSliq/WSliq.htm).
We estimate approximately 2 to 6 inches of liquefaction-induced settlement of the ground surface
based on our understanding of the regional geology and the alluvial deposits of the site. Lateral
spreading displacements are estimate to be between ½ and 3 feet. Vertical foundation settlements
should be reduced given that the aggregate piers densify the ground, increase soil stiffness, and are
embedded in dense material that is not expected to liquefy. Furthermore, the mat foundation
recommended will reduce the effect of lateral spread displacements over the building footprint for
those structures located within 250 feet of the river. However, the ground located outside the
aggregate pier improvements will be subject to liquefaction-induced settlement therefore, we
recommend any utilities connected to the proposed structures be designed with flexible connections
to reduce damage during a seismic event.
4.6 Lateral Earth Pressures
Reinforced concrete walls with unbalanced backfill levels on opposite sides should be designed
for earth pressures at least equal to those indicated in the following table. Earth pressures will be
influenced by structural design of the walls, conditions of wall restraint, methods of construction
and/or compaction and the strength of the materials being restrained. Two wall restraint conditions
are shown. Active earth pressure is commonly used for design of free-standing cantilever
retaining walls and assumes wall movement. The "at-rest" condition assumes no wall movement.
The recommended design lateral earth pressures do not include a factor of safety and do not
provide for possible hydrostatic pressure on the walls.
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Earth Pressure Coefficients
Earth Pressure
Conditions
Coefficient for
Backfill Type
Equivalent Fluid
Density (pcf)
Surcharge
Pressure, p1 (psf)
Earth Pressure,
p2 (psf)
Active (Ka)
n Level
n 2H:1V
0.31
0.45
40
60
(0.31)S
(0.45)S
(40)H
(60)H
At-Rest (Ko)
n Level
n 2H:1V
0.47
0.68
60
90
(0.47)S
(0.68)S
(60)H
(90)H
Passive (Kp)3.25 350 ------
Applicable conditions to the above include:
n For active earth pressure, wall must rotate about base, with top lateral movements of about
0.002 H to 0.004 H, where H is wall height
n For passive earth pressure to develop, wall must move horizontally to mobilize resistance
n Uniform surcharge, where S is surcharge pressure
n In-situ soil backfill weight a maximum of 130 pcf
n Horizontal backfill, compacted between 92 and 95 percent of standard Proctor maximum dry
density
n Loading from heavy compaction equipment not included
n No hydrostatic pressures acting on wall
n No dynamic loading
n No safety factor included
n Ignore passive pressure in frost zone
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Backfill placed against structures should consist of granular soils as described in Section 4.2.4.
For these values to be valid, the granular backfill must extend out and up from the base of the
wall at an angle of at least 45 and 60 degrees from vertical for the active and passive cases,
respectively. To calculate the resistance to sliding, a value of 0.45 should be used as the ultimate
coefficient of friction between the footing and crushed rock fill (i.e. material used for aggregate
piers).
A perforated rigid plastic or metal drain line installed behind the base of walls that extend below
adjacent grade is recommended to prevent hydrostatic loading on the walls. The invert of a drain
line around a below-grade building area or exterior retaining wall should be placed near
foundation bearing level. The drain line should be sloped to provide positive gravity drainage or
to a sump pit and pump. The drain line should be surrounded by clean, free-draining granular
material having less than 5 percent passing the No. 200 sieve. The free-draining aggregate should
be encapsulated in a filter fabric. The granular fill should extend to within 2 feet of final grade,
where it should be capped with compacted cohesive fill to reduce infiltration of surface water into
the drain system.
As an alternative to free-draining granular fill, a pre-fabricated drainage structure may be used. A
pre-fabricated drainage structure is a plastic drainage core or mesh, which is covered with filter
fabric to prevent soil intrusion, and is fastened to the wall prior to placing backfill.
If controlling hydrostatic pressure behind the wall as described above is not possible, then
combined hydrostatic and lateral earth pressures should be calculated for granular backfill, an
equivalent fluid weighing 85 and 90 pcf should be used for active and at-rest, respectively. These
pressures do not include the influence of surcharge, equipment or pavement loading, which
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should be added. Heavy equipment should not operate within a distance closer than the exposed
height of retaining walls to prevent lateral pressures more than those provided.
4.7 Pavements
We encountered undocumented fill soil to depths of 4 to 18 feet in our explorations. Provided the
owner is willing to accept the risk of unpredictable settlement response of the undocumented fill
under pavement sections, we recommend limited risk mitigation measures including removal of
at least the upper 12 inches of pavement subgrade, scarification and compaction of the exposed
subgrade, and replacement of the removed material with structural fill in accordance with the
earthwork section of this report. Based on the results of our explorations, the undocumented fill
soil is generally in a loose to very dense condition and represents a moderate risk of excessive
settlements due to traffic loading after completion of the recommended improvements, though
areas of unsuitable or compressible fill may be present within the fill areas that were not observed
in our explorations.
4.7.1 Subgrade Preparation
On most project sites, the site grading is accomplished relatively early in the construction phase.
However, as construction proceeds, excavations are made into these areas, rainfall and surface
water saturates some areas, heavy traffic from concrete trucks and other construction vehicles
disturbs the subgrade, and many surface irregularities are filled in with loose soil to temporarily
improve driving conditions. As a result, the pavement subgrades, initially prepared early in the
project, should be carefully evaluated as the time for pavement construction approaches.
We recommend that the moisture content and density of the top 12 inches of the subgrade be
evaluated and that the pavement subgrades be proofrolled within two days prior to commencement
of actual paving operations. Areas not in compliance with the required ranges of moisture or density
should be moisture conditioned and recompacted. Particular attention should be paid to high traffic
areas that were rutted and disturbed earlier and to areas where backfilled trenches are located.
Areas where unsuitable conditions are located should be repaired by removing and replacing the
materials with properly compacted structural fills. If a significant precipitation event occurs after the
evaluation or if the surface becomes disturbed, the subgrade should be reviewed by qualified
personnel immediately prior to paving. The subgrade should be in its finished form at the time of the
final review.
4.7.2 Design Considerations
We anticipate that traffic loads will be produced primarily by automobile and light traffic and by
occasional larger moving trucks and trash-removal trucks. The thickness of pavements subjected
to heavy truck traffic should be determined using expected traffic volumes, vehicle types, and
vehicle loads and should be in accordance with local, city or county ordinances.
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Pavement thickness were determined using AASHTO methods based on assumed values of
maximum ESAL loading of 100,000 (ESAL = equivalent 18-kip single axle load) for standard duty
car and light truck parking areas over a 20-year design life. For heavy-duty truck traffic areas, we
used an assumed traffic loading of 250,000 ESALs in our analysis. If traffic loading developed by
the civil engineer differs significantly from these assumed values, the pavement thickness design
should be revisited.
The minimum pavement sections outlined below were determined based on the estimated
subgrade support and post-construction traffic loading conditions. These pavement sections do
not account for heavy construction traffic during development. A partially constructed structural
section may be subjected to heavy construction traffic that can result in pavement deterioration
and premature failure. Our experience indicates that this pavement construction practice can
result in pavements that will not perform as intended. Considering this information, several
alternatives are available to mitigate the impact of heavy construction traffic on the pavement
construction. These include using thicker sections to account for the construction traffic; using
some method of soil stabilization to improve the support characteristics of the pavement
subgrade; routing heavy construction traffic around paved areas; or delaying paving operations
until as near the end of construction as is feasible.
Pavement performance is affected by its surroundings. In addition to providing preventive
maintenance, the civil engineer should consider the following recommendations in the design and
layout of pavements:
n Final grade adjacent to parking lots and drives should slope down from pavement edges at a
minimum 2 percent;
n The subgrade and the pavement surface should have a minimum ¼ inch per foot slope to
promote proper surface drainage;
n Install pavement drainage surrounding areas anticipated for frequent wetting (e.g., landscaping
areas, etc.);
n Install joint sealant and seal cracks immediately;
n Seal all landscaped areas in, or adjacent to pavements to reduce moisture migration to
subgrade soil, and;
n Place compacted, low permeability backfill against the exterior side of curb and gutter
Our pavement design was conducted using a CBR value of 88 percent at 95 percent compaction.
To obtain this CBR value in the field, the pavement subgrade must be thoroughly compacted to
at least 95 percent of the modified Proctor density within 2 percent of its optimum moisture. Any
imported structural fill placed below proposed pavement areas should have a CBR value of at
least 20 percent.
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4.7.3 Asphaltic Cement Concrete Thickness
MINIMUM STANDARD-DUTY PAVEMENT SECTION FOR
CAR AND LIGHT TRUCK-ONLY AREAS
Layer Thickness
(inches)
Compaction/Material
Specification
Asphalt Surface 3.0 WSDOT: 9-03.8(2) ¾-inch HMA
WSDOT: 9-03.8(6) ¾-inch Aggregate
Crushed Aggregate Base 4.0 WSDOT: 9-03.9(3) Base Course
Compacted Structural Fill
Subgrade 12 95% of Modified Proctor MDD, -2 to
+2% OMC
Total Pavement Section 7.0
MINIMUM HEAVY DUTY-PAVEMENT SECTION FOR TRUCK AREAS
Layer Thickness
(inches)
Compaction/Material
Specification
Asphalt Surface Course 4.0 WSDOT: 9-03.8(2) ¾-inch HMA
WSDOT: 9-03.8(6) ¾-inch Aggregate
Crushed Aggregate Base 6.0 WSDOT: 9-03.9(3) Base Course
Compacted Structural Fill
Subgrade 12 95% of Modified Proctor MDD, -2 to
+2% OMC
Total Pavement Section 10.0
The abbreviations MDD, OMC, and HMA in the tables above refer to Maximum Dry Density,
Optimum Moisture Content, and Hot Mix Asphalt, respectively. The graded crushed aggregate
base should be compacted to a minimum of 95 percent of the material’s modified Proctor (ASTM
D 1557, Method C) maximum dry density. We recommend that asphalt be compacted to a
minimum of 92 percent of the Rice (theoretical maximum) density or 96 percent of Marshall
(maximum laboratory) density.
We recommend that a Portland cement concrete pavement (CCP) be utilized in entrance and exit
sections, dumpster pads, loading dock areas, or other areas where extensive wheel maneuvering
or repeated loading are expected. The dumpster pad should be large enough to support the
wheels of the truck which will bear the load of the dumpster. We recommend a minimum of 6
inches of CCP underlain by 4 inches of crushed aggregate base. Although not required for
structural support, the base course layer is recommended to help reduce potentials for slab curl,
shrinkage cracking, and subgrade “pumping” through joints. Proper joint spacing will also be
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required to prevent excessive slab curling and shrinkage cracking. All joints should be sealed to
prevent entry of foreign material and dowelled where necessary for load transfer.
Portland cement concrete should be designed with proper air-entrainment and have a minimum
compressive strength of 4,000 psi after 28 days of laboratory curing. Adequate reinforcement and
number of longitudinal and transverse control joints should be placed in the rigid pavement in
accordance with ACI requirements. The joints should be sealed as soon as possible (in
accordance with sealant manufacturer’s instructions) to minimize water infiltration into the soil.
4.7.4 Pavement Drainage
Pavements should be sloped to provide rapid drainage of surface water. Water allowed to pond on
or adjacent to the pavements could saturate the subgrade and contribute to premature pavement
deterioration. In addition, the pavement subgrade should be graded to provide positive drainage
within the crushed aggregate base section.
We recommend drainage be included at the bottom of the crushed aggregate base layer at the
storm structures to aid in removing water that may enter this layer. Drainage could consist of small
diameter weep holes excavated around the perimeter of the storm structures. The weep holes
should be excavated at the elevation of the crushed aggregate base and soil interface. The
excavation should be covered with crushed aggregate which is encompassed in Mirafi 140NL or
approved equivalent which will aid in reducing fines from entering the storm system.
4.7.5 Pavement Maintenance
The pavement sections provided in this report represent minimum recommended thicknesses
and, as such, periodic maintenance should be anticipated. Therefore preventive maintenance
should be planned and provided for through an on-going pavement management program.
Maintenance activities are intended to slow the rate of pavement deterioration and to preserve
the pavement investment. Maintenance consists of both localized maintenance (e.g. crack and
joint sealing and patching) and global maintenance (e.g. surface sealing). Preventive
maintenance is usually the first priority when implementing a pavement maintenance program.
Additional engineering observation is recommended to determine the type and extent of a cost
effective program. Even with periodic maintenance, some movements and related cracking may
still occur and repairs may be required.
4.8 Settling Pond Reconnaissance
Along the southern boundary of the property, exist three (3) settling ponds and an infiltration basin.
The settling ponds were investigated to characterize the types of materials of the ponds,
approximate size and dimensions of the ponds, water depth, and sediment thickness. The findings
of the reconnaissance are summarized on an annotated, conceptual sketches provided in Exhibit
A-3. The table below summarizes the results of the reconnaissance.
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Feature
Approximate
Dimensions
(ft; W x L)
Water Depth
(ft.; average)
Sediment
Thickness (ft; bgs)
Concrete Side-
Wall Thickness
(ft; bgs)
Settling Pond
(North)50 x 47 5 1 ½5 ½
Settling Pond
(Middle)56 x 46 6 1 3
Settling Pond
(South)56 x 115 4 3 5
Infiltration
Basin 28 x 55 ---------
The upper 5 to 6 feet of material surrounding the ponds is generally concrete as observed from
the side walls of the ponds. Some reinforcement was observed but appears to be inconsistent
within the exposed and fractured concrete. The concrete appears to be moderately to highly
weathered and is spalling in most areas. Native material is observed around some sections of the
pond, primarily along the northeastern boundary (i.e. side opposite the river). Dividing the ponds
are concrete fingers approximately 14 ½ to 17 ½ feet wide with 9-foot weirs between sidewalls
allowing water flow between ponds.
Demolition of the settling ponds should include dewatering and excavation of the retained
sediments to expose firm, native subgrade. Due to the site history, the retained water and
sediments may require treatment prior to disposal. Appropriate environmental testing should be
considered to characterize potential contaminants within the materials. Demolition of the settling
ponds should consider the temporary slope cut recommendations provided in Section 4.2.3.
Backfilling should be performed in accordance with Section 4.2.4 and 4.2.5.
5.0 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
Revised Geotechnical Engineering Report
Cedar River Apartments Renton, Washington
October 31, 2018 Terracon Project No. 81175025
Responsive Resourceful Reliable 24
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.
This report has been prepared for the exclusive use of our client for specific application to the
project discussed and has been prepared in accordance with generally accepted geotechnical
engineering practices. 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.
APPENDIX A
FIELD EXPLORATION
Project Mngr:
Approved By:
Checked By:
Drawn By:
Project No.
Scale:
Date:
File No.
EXHIBIT
Consulting Engineers and Scientists
21905 64th Avenue W., Ste 100 Mountlake Terrace, WA 98043
FAX. (425) 771-3549PH. (425) 771-3304
SITE LOCATION MAP
Cedar River Apartments
1915 Maple Valley Highway
Renton, King County, Washington A-1OCT. 2018
Exhibit A-1
AS SHOWN
81175025RDL
AMP
ZLK
DAB
SITE
LEGEND
Source: USGS Renton, Washington,
7.5-minute Quadrangle, published 2017.
APPROXIMATE SCALE IN FEET
01500 375 1500750
B-3 (50 FT)
B-4 (50 FT)
TP-9
TP-10
50'
47'46'59'
56'
56'
56'53'
CEDAR RIVER
GRAVEL
BALLAST
17.5'
16.0'
MW7
W1
W2 W3
W4
W5
W6
W7
W8
W9 W10
W11
W12
W13
W16
W15
W14
W17
INFILTRATION BASINMETAL
CANOPY
ECOLOGY
BLOCKS (TYP)
QUARRY SPALLS
8"-10"
QUARRY
SPALLS
CONCRETE
PEA GRAVEL
7'
9'
16'6'
5"-8"
CONCRETE
K-RAIL (12' TYP)
OBSERVATION
WELLS
SUBMERGED
CONCRETECONCRETE
Project Mngr:
ApprovedBy:
Checked By:
Drawn By:
ProjectNo.
Scale:
Date:
File No.Consulting Engineers and Scientists
EXHIBIT
21905 64th AvenueW,Ste100 Mountlake Terrace,WA98043
FAX. (425) 771-3549PH. (425) 771-3304
SETTLING POND SUMMARY
Cedar River Apartments
1915 Maple Valley Highway
Renton, King County, Washington A-3OCT. 2018
Exhibit 1
AS SHOWN
81175025RDL
AMP
HKO
DAB
N
LEGEND
SUMMARY OF OBSERVATIONS
LOCATION
SIDEWALL
CONCRETE
THICKNESS
(FT)
WATER DEPTH
(FT)
WALL HEIGHT
ABOVE WATER
(FT)
SEDIMENT
THICKNESS
(FT)
W1 8 6.7 9.5 1
W2 6.4 7.5 1.0
W3 4.8 7.5
W4 5.5 4.3 7.5 1.5
W5 2.5 4.2 8
W6 4 7.0 2
W7 5.2 7.5
W8 2 7.0 7.5
W9 6.2 8
W10 6.5 7 1
W11 4 6.8 6.5
W12 7.1 6 1.5
W13 2 7.4 5
W14 7.7 5
W15 8.0 4 2.5
W16 3.5 8.3 3.5
W17 8.6 3 2.5
W1
SCALE IN FEET
030 10 3020
B-1 (DEPTH; BGS)APPROXIMATEBORING
LOCATION AND NUMBER
TP-1 APPROXIMATETESTPIT
LOCATION AND NUMBER
APPROXIMATEPROBE
LOCATION AND NUMBER
APPROXIMATE MONITORING WELL
LOCATION AND NUMBER (BY OTHERS)MW1
Geotechnical Engineering Report
Cedar River Apartments Renton, Washington
October 31, 2018 Terracon Project No. 81175025
Responsive Resourceful Reliablee Exhibit A-4
Field Exploration Description
The exploration locations were laid out in the field by a Terracon representative using a scaled
site plan provided by the client and utilizing hand-held GPS equipment. Ground surface elevations
indicated on the exploration logs were estimated to the nearest ½ foot from an architectural site
plan provided to Terracon by Rutledge Maul Architects dated 7/25/2017. The locations and
elevations of the explorations should be considered accurate only to the degree implied by the
means and methods used to define them.
Borings B-3, B-4, B-5, and B-7 were drilled using a Mobile B-58 rotary drill rig. Boreholes B-2 and
B-6 were drilled using a CME-75, while B-1 was drilled using a CME-85 rotary drill rig. All of the
borings used hollow-stem augers to advance the boreholes. Samples of the soil encountered in
the borings were obtained using the split-barrel sampling procedures.
In the split-barrel sampling procedure, the number of blows required to advance a standard 2-
inch O.D. split-barrel sampler the last 12 inches of the typical total 18-inch penetration by means
of a 140-pound hammer with a free fall of 30 inches, is the standard penetration resistance value
(SPT-N). This value is used to estimate the in situ relative density of cohesionless soils and
consistency of cohesive soils.
An automatic SPT hammer was used to advance the split-barrel sampler in the borings performed
on this site. A significantly greater efficiency is achieved with the automatic hammer compared to
the conventional safety hammer operated with a cathead and rope. This higher efficiency has an
appreciable effect on the SPT-N value. The effect of the automatic hammer's efficiency has been
considered in the interpretation and analysis of the subsurface information for this report. The
Mobile B-58 had a hammer efficiency of 104.0%. The CME-75 rotary drill rig had a hammer
efficiency of 77.0%, while the CME-85 had a hammer efficiency of 87.0%.
The samples were tagged for identification, sealed to reduce moisture loss, and taken to our
laboratory for further examination, testing, and classification. Information provided on the boring
logs attached to this report includes soil descriptions, consistency evaluations, boring depths,
sampling intervals, and groundwater conditions. The borings were backfilled with auger cuttings
prior to the drill crew leaving the site.
A total of 12 test pits were performed to depths of 4 to 10 feet using a Bobcat 335 Mini-excavator.
Probing was conducted within the excavated area at depths of 2 and 4 feet bgs to infer density of
the existing fill. Material deeper than 4 feet was visually classified from the excavation stockpile.
A field log of each exploration was prepared by a Terracon geotechnical engineer geologist.
These logs included visual classifications of the materials encountered during drilling as well as
the engineer’s geologist’s interpretation of the subsurface conditions between samples. Final
boring logs included with this report represent the engineer's interpretation of the field logs and
include modifications based on laboratory observation and tests of the samples.
APPENDIX B
LABORATORY TESTING
Geotechnical Engineering Report
Cedar River Apartments Renton, Washington
October 31, 2018 Terracon Project No. 81175025
Responsive Resourceful Reliablee Exhibit B-1
Laboratory Testing Description
Soil samples were tested in the laboratory to measure their natural water content. The test results
are provided on the boring logs included in Appendix A.
Descriptive classifications of the soils indicated on the boring logs are in accordance with the
enclosed General Notes and the Unified Soil Classification System. Also shown are estimated
Unified Soil Classification Symbols. A brief description of this classification system is attached to
this report. All classification was by visual manual procedures. Selected samples were further
classified using the results of grain size distribution and Atterberg limit testing. The Atterberg limit
test and fines content results are also provided on the boring logs.
Moisture-density relationship testing, or compaction testing, is a laboratory method of
experimentally determining the optimal moisture content at which a given soil type will become
most dense and achieve its maximum dry density. Compaction testing was conducted as part of
the California Bearing Ratio (CBR) testing procedure. The compaction testing results predict a
maximum dry density of 139.8 pounds per cubic foot (pcf) at an optimum moisture of 6.7 percent.
California bearing ratio (CBR) is a penetration test for evaluation of the mechanical strength of
natural ground, subgrades and basecourses beneath new carriageway construction. The test is
performed by measuring the pressure required to penetrate soil or aggregate with a plunger of
standard area. The measured pressure is then divided by the pressure required to achieve an
equal penetration on a standard crushed rock material, namely California limestone. The CBR for
the material sampled in the upper 2 ½ feet is 88 percent at a compaction of 95 percent of the
maximum dry density.
Sample testing includes the following quantities:
n 12 - Grain Size Distribution (ASTM D6913)
n 11 - #200 Wash (ASTM D6913)
n 1 – Moisture-Density Relationship (ASTM D1557)
n 1 – California Bearing Ratio (CBR; ASTM D1883)
APPENDIX C
SUPPORTING DOCUMENTS
Exhibit C-2
UNIFIED SOIL CLASSIFICATION SYSTEM
Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests A
Soil Classification
Group
Symbol Group Name B
Coarse Grained Soils:
More than 50% retained
on No. 200 sieve
Gravels:
More than 50% of
coarse fraction retained
on No. 4 sieve
Clean Gravels:
Less than 5% fines C
Cu 4 and 1 Cc 3 E GW Well-graded gravel F
Cu 4 and/or 1 Cc 3 E GP Poorly graded gravel F
Gravels with Fines:
More than 12% fines C
Fines classify as ML or MH GM Silty gravel F,G,H
Fines classify as CL or CH GC Clayey gravel F,G,H
Sands:
50% or more of coarse
fraction passes No. 4
sieve
Clean Sands:
Less than 5% fines D
Cu 6 and 1 Cc 3 E SW Well-graded sand I
Cu 6 and/or 1 Cc 3 E SP Poorly graded sand I
Sands with Fines:
More than 12% fines D
Fines classify as ML or MH SM Silty sand G,H,I
Fines classify as CL or CH SC Clayey sand G,H,I
Fine-Grained Soils:
50% or more passes the
No. 200 sieve
Silts and Clays:
Liquid limit less than 50
Inorganic:PI 7 and plots on or above “A” line J CL Lean clay K,L,M
PI 4 or plots below “A” line J ML Silt K,L,M
Organic:Liquid limit - oven dried 0.75 OL Organic clay K,L,M,N
Liquid limit - not dried Organic silt K,L,M,O
Silts and Clays:
Liquid limit 50 or more
Inorganic:PI plots on or above “A” line CH Fat clay K,L,M
PI plots below “A” line MH Elastic Silt K,L,M
Organic:Liquid limit - oven dried 0.75 OH Organic clay K,L,M,P
Liquid limit - not dried Organic silt K,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-inch (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
2
30
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.
H If 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.
Table 1
Summary of Groundwater Elevation Data
Old Stoneway Renton
Renton, Washington
Farallon PN: 266-008
DRAFT - Issued for Client Review
6/8/2009 18.63 29.30
9/29/2016 19.62 28.31
12/14/2009 19.10 28.83
3/3/2010 18.58 29.35
6/1/2010 17.58 30.35
8/10/2010 20.78 27.15
9/14/2010 19.57 28.36
9/15/2016 19.91 28.02
6/8/2009 22.58 29.51
9/29/2016 23.48 28.61
12/14/2009 22.95 29.14
3/3/2010 22.53 29.56
6/1/2010 21.59 30.50
8/10/2010 24.45 27.64
9/14/2010 23.39 28.70
9/15/2016 23.71 28.38
6/8/2009 13.68 29.97
9/29/2009 15.75 27.90
12/14/2009 14.20 29.45
3/3/2010 13.80 29.85
6/1/2010 12.68 30.97
8/10/2010 15.56 28.09
9/14/2010 14.72 28.93
6/8/2009 14.29 31.89
9/29/2009 15.23 30.95
12/14/2009 14.77 31.41
3/3/2010 14.48 31.70
6/1/2010 13.25 32.93
8/10/2010 15.59 30.59
9/14/2010 15.13 31.05
6/8/2009 12.11 31.94
9/29/2016 13.03 31.02
12/14/2009 12.69 31.36
3/3/2010 12.25 31.80
6/1/2010 11.10 32.95
8/10/2010 13.44 30.61
9/14/2010 13.06 30.99
9/15/2016 13.23 30.82
6/8/2009 15.35 30.47
9/29/2009 16.70 29.12
12/14/2009 15.81 30.01
3/3/2010 15.45 30.37
6/1/2010 14.40 31.42
8/10/2010 17.00 28.82
9/14/2010 16.22 29.60
EPI-MW-1 NA NA 52.09
Well
Identification
Monitoring
Date
Depth of
Monitoring Well
(feet)
Monitoring Well
Screened Interval
(feet bgs)
Wellhead Elevation 1
(feet)
Groundwater
Elevation
(feet)
MW-1 NA NA 47.93
Depth to
Water (below
TOC)
EPI-MW-7 17.0 5.0-17.0 44.05
EPI-MW-8 NA NA 45.82
EPI-MW-5 NA NA 43.65
EPI-MW-6 NA NA 46.18
G:\Projects\266 Gary Merlino Const Entities\266008 Old Stoneway Renton\Working Folder\Reports\2016\Tables\Tables 1 and 2.xlsx
1 of 2
DRAFT - Issued for Client Review
Table 1
Summary of Groundwater Elevation Data
Old Stoneway Renton
Renton, Washington
Farallon PN: 266-008
DRAFT - Issued for Client Review
Well
Identification
Monitoring
Date
Depth of
Monitoring Well
(feet)
Monitoring Well
Screened Interval
(feet bgs)
Wellhead Elevation 1
(feet)
Groundwater
Elevation
(feet)
Depth to
Water (below
TOC)
6/8/2009 16.84 31.41
9/29/2016 17.95 30.30
12/14/2009 17.39 30.86
3/3/2010 17.08 31.17
6/1/2010 15.94 32.31
8/10/2010 18.31 29.94
9/14/2010 17.76 30.49
9/15/2016 18.32 29.93
7/20/2015 NA 30.72
1/13/2016 NA 32.53
9/15/2016 11.51 NC
6/8/2009 10.61 30.80
9/29/2009 12.40 29.01
12/14/2009 11.16 30.25
3/3/2010 10.80 30.61
6/1/2010 9.64 31.77
8/10/2010 12.24 29.17
9/14/2010 11.60 29.81
NOTES
NA = not available
NC =not calculated
1In feet at top of well casing.Monitoring Well Survey Data Obtained
from Interim Action Report, Former Stoneway Batch Plant, 1915 SE
Maple Valley Highway, Renton, Washington, dated February 7, 2011
prepared by Environmental Partners Inc.TOC = top of casing
EPI-MW-9 19.0 7.0-19.0 48.25
MW-41 NA NA 41.41
MW-10 NA NA NA
G:\Projects\266 Gary Merlino Const Entities\266008 Old Stoneway Renton\Working Folder\Reports\2016\Tables\Tables 1 and 2.xlsx
2 of 2
DRAFT - Issued for Client Review
Liquefaction Hazard Evaluation Report
by WSLiq Program beta (May, 2009)
---------------------------------------------------
Site Name: Cedar River Apartments - Renton, WA (B1)
Site Location (N,W) = 47.480 , 122.194
Job No: 81175025
Analyst: Koehn
Date: 7/26/2017 8:20:46 AM
---------------------------------------------------
=== Soil Profile ===
Unit: ft
The number of soil layers: 10
GWT at top of layer: 7
GWT depth: 21.00
SPT Energy Ratio (%): 87.00
Amplification Factors: a= -0.1500 b= -0.1300
Elevation: 50.00
Ground Surface: Infinite Slope (%)= 1.5
Layer Descpt. Thickness Unit Weight Nm N160 Vs
(ft) (lb/ft3) ft/sec
1 SILTY_SAND_-_FILL_(SM) 4.5 120.00 17 41.9 835.9
2 SILTY_SAND_-_FILL_(SM) 2.5 120.00 51 125.7 1149.5
3 SAND_W/_SILT_AND_GRAVEL_(SP-SM) 2.5 120.00 31 65.7 995.0
4 SAND_W/_SILT_AND_GRAVEL_(SP-SM) 3.5 120.00 22 39.9 900.8
5 SAND_W/_GRAVEL_(SP) 5 120.00 36 55.7 1039.1
6 SAND_W/_GRAVEL_(SP) 3 120.00 19 26.2 863.3
7 SAND_W/_GRAVEL_(SP) 2 120.00 19 25.0 863.3
8 GRAVEL_W/_SAND_(SW) 5 130.00 28 35.3 966.0
9 GRAVEL_W/_SAND_(SW) 4.5 130.00 46 54.9 1115.6
10 GRAVEL_W/_SAND_(SW) 2.5 130.00 35 40.3 1030.6
Layer FC PI wc/LL D50 Ini. Eff. Ini. Total
(%) (mm) Stress (psf) Stress (psf)
1 20 Unsat Unsat 1.000 270.0 270.00
2 20 Unsat Unsat 1.000 690.0 690.00
3 7 Unsat Unsat 1.000 990.0 990.00
4 7 Unsat Unsat 1.000 1350.0 1350.00
5 4 Unsat Unsat 1.000 1860.0 1860.00
6 4 Unsat Unsat 1.000 2340.0 2340.00
7 4 0 1.5 1.000 2577.6 2640.00
8 12 0 1.5 10.000 2804.2 3085.00
9 12 0 1.5 10.000 3125.3 3702.50
10 12 0 1.5 10.000 3361.9 4157.50
Soil Profile Plots
1
=== Initiation ===
---------------------------------------------------
Initiation - Multiple Scenario
-----------------------------------------
Retrun Period (yrs) = 2475.0
Models Selected :
Use All Deterministic Models.
--WSDOT Recommended--
Use NCEER, Boulanger & Idriss, and
Cetin's model with weighting factors
of 0.4, 0.4, and 0.2 respectively.
----------------------------------------
===== Mean Mw and FS ==============
---NCEER Model------------
--- PGA = 0.578 Mw = 6.67---------
2
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
7 24.96 0.249 0.273 1.10 21.8
8 35.27 0.261 3.000 11.51 22.5
9 54.89 0.269 3.000 11.14 23.0
10 40.26 0.271 3.000 11.06 23.1
===== Mean Mw and FS ==============
---Boulanger and Idriss Model------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
7 25.48 0.285 0.292 1.02 24.4
8 37.15 0.300 3.000 10.01 25.1
9 46.00 0.313 3.000 9.60 25.6
10 44.79 0.318 3.000 9.42 25.8
===== Mean Mw and FS ==============
---Cetin et al. Model------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
7 24.96 0.384 0.369 0.96 25.7
8 35.27 0.411 0.887 2.16 25.8
9 54.89 0.442 2.989 6.77 27.1
10 40.26 0.460 1.250 2.72 27.8
---WSDOT Recommended------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
7 24.96 0.290 0.300 1.03 23.6
8 35.27 0.306 2.577 8.41 24.2
9 54.89 0.321 2.998 9.34 24.8
10 40.26 0.328 2.650 8.08 25.1
Table of FS
---------------------------------------
# Depth NCEER B&I Cetin WSDOT
ft PL=0.60 PL=0.60
7 -22.00 1.10 1.02 0.96 1.03
8 -25.50 11.51 10.01 2.16 8.41
9 -30.25 11.14 9.60 6.77 9.34
10 -33.75 11.06 9.42 2.72 8.08
3
=== Effects ===
---------------------------------------------------
** Lateral Spreading **
(Infinite Slope: 1.5%)
-----------------------
>>>Multiple Scenario Results
Model Selected :
WSDOT Recommended (weighted average)
using models of Baska & Kramer and Youd et al.
-----------------------------------------
Baska & Kramer: 1.07 ft
Youd et al.: 0.00 ft (Notice: T15 = 0)
Idriss & Boulanger: 0.18 ft
----------------------------------------
Weighting factors: Baska and Kramer = 0.65
Youd et al. = 0.35
WSDOT Recommended: 0.69 ft
4
** Lateral Spreading **
(Free-Face Slope: 4.3%)
-----------------------
>>>Multiple Scenario Results
Model Selected :
WSDOT Recommended (weighted average)
using models of Baska & Kramer and Youd et al.
-----------------------------------------
Baska & Kramer: 0.38 ft
Youd et al.: 0.00 ft (Notice: T15 = 0)
Idriss & Boulanger: 0.05 ft
----------------------------------------
Weighting factors: Baska and Kramer = 0.65
Youd et al. = 0.35
WSDOT Recommended: 0.24 ft
=== Effects ===
---------------------------------------------------
** Settlement **
----------------
>>>Multiple Scenario Results
Groud Surface Settlement MULTIPLE Scenario
Return Period (yrs) = 2475.0
Model Selected :
Use all deterministic models.
-----------------------------------------
Tokimatsu & Seed
=================
Total ground surface settlement = 0.01 ft
----------------------------------------------
# Depth thickness ev Weight dh 5
ft ft % ft
----------------------------------------------
7 22.00 2.0 0.357 0.89 0.01
8 25.50 5.0 0.001 0.00 0.00
9 30.25 4.5 0.001 0.00 0.00
10 33.75 2.5 0.001 0.00 0.00
----------------------------------------------
Ishihara & Yoshimine
=================
Total ground surface settlement = 0.01 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
7 22.00 2.0 0.671 0.64 0.01
8 25.50 5.0 0.001 0.00 0.00
9 30.25 4.5 0.001 0.00 0.00
10 33.75 2.5 0.001 0.00 0.00
----------------------------------------------
Shamoto et al.
=================
Total ground surface settlement = 0.00 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
7 22.00 2.0 0.500 0.39 0.00
8 25.50 5.0 0.000 0.00 0.00
9 30.25 4.5 0.000 0.00 0.00
10 33.75 2.5 0.000 0.00 0.00
----------------------------------------------
Wu & Seed
=================
Total ground surface settlement = 0.01 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
7 22.00 2.0 0.882 0.51 0.01
8 25.50 5.0 0.008 0.00 0.00
9 30.25 4.5 0.000 0.00 0.00
10 33.75 2.5 0.002 0.00 0.00
----------------------------------------------
6
Liquefaction Hazard Evaluation Report
by WSLiq Program beta (May, 2009)
---------------------------------------------------
Site Name: Cedar River Apartments - Renton, WA (B2)
Site Location (N,W) = 47.480 , 122.194
Job No: 81175025
Analyst: Koehn
Date: 7/26/2017 8:53:00 AM
---------------------------------------------------
=== Soil Profile ===
Unit: ft
The number of soil layers: 11
GWT at top of layer: 6
GWT depth: 18.00
SPT Energy Ratio (%): 77.00
Amplification Factors: a= -0.1500 b= -0.1300
Elevation: 48.50
Ground Surface: Infinite Slope (%)= 2.6
Layer Descpt. Thickness Unit Weight Nm N160 Vs
(ft) (lb/ft3) ft/sec
1 SILTY_SAND_-_FILL_(SM) 4.5 120.00 100 218.2 1348.8
2 SILTY_SAND_(SM) 3.5 120.00 65 140.1 1190.4
3 SILTY_SAND_(SM) 1.5 120.00 100 182.2 1348.8
4 SILTY_SAND_(SM) 3.0 120.00 100 162.5 1348.8
5 SILTY_SAND_(SM) 5.5 120.00 3 4.1 487.9
6 SILTY_SAND_(SM) 5 120.00 8 9.8 648.4
7 SILTY_SAND_(SM) 4 120.00 13 15.2 746.4
8 SILTY_SAND_(SM) 2.5 120.00 4 4.5 530.3
9 GRAVEL_W/_SILT_&_SAND_(GP-GM) 3.5 130.00 45 49.0 1070.0
10 GRAVEL_W/_SILT_&_SAND_(GP-GM) 5 130.00 78 81.0 1255.0
11 GRAVEL_W/_SILT_&_SAND_(GP-GM) 3.5 130.00 57 56.8 1145.9
Layer FC PI wc/LL D50 Ini. Eff. Ini. Total
(%) (mm) Stress (psf) Stress (psf)
1 20 Unsat Unsat 1.000 270.0 270.00
2 20 Unsat Unsat 1.000 750.0 750.00
3 7 Unsat Unsat 1.000 1050.0 1050.00
4 7 Unsat Unsat 1.000 1320.0 1320.00
5 12 Unsat Unsat 1.000 1830.0 1830.00
6 35 0 1 1.000 2304.0 2460.00
7 20 0 1 1.000 2563.2 3000.00
8 20 0 1 1.000 2750.4 3390.00
9 7 0 1 10.000 2940.7 3767.50
10 7 0 1 10.000 3228.0 4320.00
11 7 0 1 10.000 3515.3 4872.50
Soil Profile Plots
1
=== Initiation ===
---------------------------------------------------
Initiation - Multiple Scenario
-----------------------------------------
Retrun Period (yrs) = 2475.0
Models Selected :
Use All Deterministic Models.
--WSDOT Recommended--
Use NCEER, Boulanger & Idriss, and
Cetin's model with weighting factors
of 0.4, 0.4, and 0.2 respectively.
-----------------------------------------
===== Mean Mw and FS ==============
---NCEER Model------------
--- PGA = 0.578 Mw = 6.67---------
2
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
6 9.84 0.262 0.176 0.67 22.6
7 15.16 0.278 0.205 0.74 23.5
8 4.50 0.285 0.095 0.33 23.8
9 48.99 0.288 3.000 10.40 24.0
10 81.05 0.288 3.000 10.42 23.9
11 56.76 0.283 3.000 10.61 23.7
===== Mean Mw and FS ==============
---Boulanger and Idriss Model------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
6 9.80 0.300 0.157 0.52 25.1
7 15.20 0.320 0.197 0.62 25.9
8 4.36 0.330 0.108 0.33 26.2
9 46.00 0.336 3.000 8.94 26.4
10 46.00 0.340 3.000 8.82 26.5
11 46.00 0.342 3.000 8.78 26.5
===== Mean Mw and FS ==============
---Cetin et al. Model------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
6 9.84 0.396 0.148 0.37 21.6
7 15.16 0.430 0.200 0.46 24.9
8 4.50 0.449 0.083 0.18 25.6
9 48.99 0.462 2.288 4.95 28.2
10 81.05 0.473 3.000 6.34 28.8
11 56.76 0.478 2.989 6.26 29.3
---WSDOT Recommended------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
6 9.84 0.304 0.163 0.54 23.4
7 15.16 0.325 0.201 0.62 24.7
8 4.50 0.336 0.098 0.29 25.1
9 48.99 0.342 2.858 8.35 25.8
10 81.05 0.346 3.000 8.67 26.0
11 56.76 0.345 2.998 8.68 25.9
Table of FS
---------------------------------------
# Depth NCEER B&I Cetin WSDOT
ft PL=0.60 PL=0.60
6 -20.50 0.67 0.52 0.37 0.54
7 -25.00 0.74 0.62 0.46 0.62
8 -28.25 0.33 0.33 0.18 0.29
9 -31.25 10.40 8.94 4.95 8.35
10 -35.50 10.42 8.82 6.34 8.67
11 -39.75 10.61 8.78 6.26 8.68
3
=== Effects ===
---------------------------------------------------
** Lateral Spreading **
(Infinite Slope: 2.6%)
-----------------------
>>>Multiple Scenario Results
Model Selected :
WSDOT Recommended (weighted average)
using models of Baska & Kramer and Youd et al.
-----------------------------------------
Baska & Kramer: 2.43 ft
Youd et al.: 0.62 ft
Idriss & Boulanger: 5.25 ft
----------------------------------------
Weighting factors: Baska and Kramer = 0.65
Youd et al. = 0.35
WSDOT Recommended: 1.80 ft
4
** Lateral Spreading **
(Free-Face Slope: 7.6%)
-----------------------
>>>Multiple Scenario Results
Model Selected :
WSDOT Recommended (weighted average)
using models of Baska & Kramer and Youd et al.
-----------------------------------------
Baska & Kramer: 1.42 ft
Youd et al.: 0.47 ft
Idriss & Boulanger: 1.43 ft
----------------------------------------
Weighting factors: Baska and Kramer = 0.65
Youd et al. = 0.35
WSDOT Recommended: 1.09 ft
=== Effects ===
---------------------------------------------------
** Settlement **
----------------
>>>Multiple Scenario Results
Groud Surface Settlement MULTIPLE Scenario
Return Period (yrs) = 2475.0
Model Selected :
5
Use all deterministic models.
-----------------------------------------
Tokimatsu & Seed
=================
Total ground surface settlement = 0.20 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
6 20.50 5.0 1.538 0.99 0.08
7 25.00 4.0 1.270 0.99 0.05
8 28.25 2.5 2.818 1.00 0.07
9 31.25 3.5 0.001 0.00 0.00
10 35.50 5.0 0.001 0.00 0.00
11 39.75 3.5 0.001 0.00 0.00
----------------------------------------------
Ishihara & Yoshimine
=================
Total ground surface settlement = 0.40 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
6 20.50 5.0 3.556 0.98 0.17
7 25.00 4.0 2.539 0.97 0.10
8 28.25 2.5 5.235 1.00 0.13
9 31.25 3.5 0.001 0.00 0.00
10 35.50 5.0 0.001 0.00 0.00
11 39.75 3.5 0.001 0.00 0.00
----------------------------------------------
Shamoto et al.
=================
Total ground surface settlement = 0.56 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
6 20.50 5.0 4.402 0.94 0.21
7 25.00 4.0 2.107 0.94 0.08
8 28.25 2.5 10.938 1.00 0.27
9 31.25 3.5 0.000 0.00 0.00
10 35.50 5.0 0.000 0.00 0.00
11 39.75 3.5 0.000 0.00 0.00
----------------------------------------------
Wu & Seed
=================
Total ground surface settlement = 0.25 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
6 20.50 5.0 2.005 0.93 0.09
7 25.00 4.0 1.626 0.91 0.06
8 28.25 2.5 3.951 1.00 0.10
9 31.25 3.5 0.000 0.00 0.00
10 35.50 5.0 0.000 0.00 0.00
11 39.75 3.5 0.000 0.00 0.00
----------------------------------------------
6
7
Liquefaction Hazard Evaluation Report
by WSLiq Program beta (May, 2009)
---------------------------------------------------
Site Name: Cedar River Apartments - Renton, WA (B3)
Site Location (N,W) = 47.480 , 122.194
Job No: 81175025
Analyst: Koehn
Date: 7/26/2017 4:17:17 PM
---------------------------------------------------
=== Soil Profile ===
Unit: ft
The number of soil layers: 12
GWT at top of layer: 5
GWT depth: 13.50
SPT Energy Ratio (%): 100.40
Amplification Factors: a= -0.1500 b= -0.1300
Elevation: 44.00
Ground Surface: Infinite Slope (%)= 3.7
Layer Descpt. Thickness Unit Weight Nm N160 Vs
(ft) (lb/ft3) ft/sec
1 SILTY_SAND_-_FILL_(SM) 4.5 120.00 76 216.2 1345.2
2 SILTY_SAND_-_FILL_(SM) 2.5 120.00 100 284.5 1456.6
3 SILTY_SAND_-_FILL_(SM) 2.5 120.00 58 141.9 1243.8
4 SILTY_SAND_-_FILL_(SM) 4 120.00 100 207.2 1456.6
5 SAND_(SP) 2 120.00 100 187.9 1456.6
6 SAND_(SP) 6 120.00 5 8.8 611.0
7 SAND_W/_SILT_&_GRAVEL_(SW-SM) 6.5 120.00 26 42.0 985.6
8 SAND_W/_SILT_&_GRAVEL_(SW-SM) 5 120.00 28 42.3 1007.0
9 SAND_W/_SILT_&_GRAVEL_(SW-SM) 5 130.00 40 57.1 1116.7
10 SAND_W/_SILT_&_GRAVEL_(SW-SM) 5 130.00 17 23.0 871.3
11 SAND_W/_SILT_&_GRAVEL_(SW-SM) 5 130.00 100 128.5 1456.6
12 SAND_W/_SILT_&_GRAVEL_(SM) 5 130.00 57 70.0 1237.5
Layer FC PI wc/LL D50 Ini. Eff. Ini. Total
(%) (mm) Stress (psf) Stress (psf)
1 20 Unsat Unsat 1.000 270.0 270.00
2 20 Unsat Unsat 1.000 690.0 690.00
3 7 Unsat Unsat 1.000 990.0 990.00
4 7 Unsat Unsat 1.000 1380.0 1380.00
5 0 N.P. N.P. 1.000 1677.6 1740.00
6 1 0 1 1.000 1908.0 2220.00
7 6 0 1 1.000 2268.0 2970.00
8 6 0 1 1.000 2599.2 3660.00
9 6 0 1 10.000 2912.2 4285.00
10 6 0 1 10.000 3250.2 4935.00
11 6 0 1 10.000 3588.2 5585.00
12 16 0 1 10.000 3926.2 6235.00
Soil Profile Plots
1
=== Initiation ===
---------------------------------------------------
Initiation - Multiple Scenario
-----------------------------------------
Retrun Period (yrs) = 2475.0
Models Selected :
Use All Deterministic Models.
--WSDOT Recommended--
Use NCEER, Boulanger & Idriss, and
Cetin's model with weighting factors
of 0.4, 0.4, and 0.2 respectively.
-----------------------------------------
===== Mean Mw and FS ==============
---NCEER Model------------
--- PGA = 0.578 Mw = 6.67---------
2
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
5 187.94 0.263 3.000 11.41 22.6
6 8.81 0.289 0.103 0.36 24.0
7 42.03 0.312 3.000 9.62 25.1
8 42.28 0.319 3.000 9.39 25.4
9 57.06 0.316 3.000 9.48 25.3
10 22.95 0.307 0.226 0.74 24.8
11 128.51 0.294 3.000 10.22 24.2
12 70.02 0.279 3.000 10.73 23.5
===== Mean Mw and FS ==============
---Boulanger and Idriss Model------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
5 46.00 0.301 3.000 9.96 25.2
6 8.86 0.331 0.110 0.33 26.3
7 42.66 0.358 3.000 8.37 27.2
8 44.30 0.371 3.000 8.09 27.5
9 46.00 0.374 3.000 8.02 27.5
10 23.87 0.372 0.248 0.67 27.4
11 46.00 0.367 3.000 8.17 27.3
12 46.00 0.361 3.000 8.32 27.0
===== Mean Mw and FS ==============
---Cetin et al. Model------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
5 187.94 0.389 3.000 7.70 25.0
6 8.81 0.437 0.115 0.26 26.8
7 42.03 0.491 1.452 2.96 28.2
8 42.28 0.527 1.425 2.70 29.6
9 57.06 0.550 2.990 5.44 30.6
10 22.95 0.565 0.303 0.54 31.3
11 128.51 0.576 3.000 5.21 31.9
12 70.02 0.583 3.000 5.15 30.7
---WSDOT Recommended------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
5 187.94 0.304 3.000 9.88 24.1
6 8.81 0.335 0.108 0.32 25.5
7 42.03 0.366 2.690 7.34 26.5
8 42.28 0.382 2.685 7.04 27.1
9 57.06 0.386 2.998 7.76 27.2
10 22.95 0.385 0.251 0.65 27.2
11 128.51 0.380 3.000 7.90 27.0
12 70.02 0.373 3.000 8.05 26.4
Table of FS
---------------------------------------
# Depth NCEER B&I Cetin WSDOT
ft PL=0.60 PL=0.60
5 -14.50 11.41 9.96 7.70 9.88
6 -18.50 0.36 0.33 0.26 0.32
7 -24.75 9.62 8.37 2.96 7.34
3
8 -30.50 9.39 8.09 2.70 7.04
9 -35.50 9.48 8.02 5.44 7.76
10 -40.50 0.74 0.67 0.54 0.65
11 -45.50 10.22 8.17 5.21 7.90
12 -50.50 10.73 8.32 5.15 8.05
=== Effects ===
---------------------------------------------------
** Lateral Spreading **
(Infinite Slope: 3.1%)
-----------------------
>>>Multiple Scenario Results
Model Selected :
WSDOT Recommended (weighted average)
using models of Baska & Kramer and Youd et al.
-----------------------------------------
Baska & Kramer: 3.30 ft
Youd et al.: 2.04 ft
Idriss & Boulanger: 14.20 ft
----------------------------------------
Weighting factors: Baska and Kramer = 0.65
Youd et al. = 0.35
WSDOT Recommended: 2.86 ft
4
** Lateral Spreading **
(Free-Face Slope: 13.8%)
-----------------------
>>>Multiple Scenario Results
Model Selected :
WSDOT Recommended (weighted average)
using models of Baska & Kramer and Youd et al.
-----------------------------------------
Baska & Kramer: 2.59 ft
Youd et al.: 1.96 ft
Idriss & Boulanger: 4.48 ft
----------------------------------------
Weighting factors: Baska and Kramer = 0.65
Youd et al. = 0.35
WSDOT Recommended: 2.37 ft
=== Effects ===
---------------------------------------------------
** Settlement **
----------------
>>>Multiple Scenario Results
Groud Surface Settlement MULTIPLE Scenario
5
Return Period (yrs) = 2475.0
Model Selected :
Use all deterministic models.
-----------------------------------------
Tokimatsu & Seed
=================
Total ground surface settlement = 0.22 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
5 14.50 2.0 0.001 0.00 0.00
6 18.50 6.0 2.754 1.00 0.17
7 24.75 6.5 0.001 0.00 0.00
8 30.50 5.0 0.001 0.00 0.00
9 35.50 5.0 0.001 0.00 0.00
10 40.50 5.0 1.051 1.00 0.05
11 45.50 5.0 0.001 0.00 0.00
12 50.50 5.0 0.001 0.00 0.00
----------------------------------------------
Ishihara & Yoshimine
=================
Total ground surface settlement = 0.34 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
5 14.50 2.0 0.001 0.00 0.00
6 18.50 6.0 4.142 1.00 0.25
7 24.75 6.5 0.001 0.00 0.00
8 30.50 5.0 0.001 0.00 0.00
9 35.50 5.0 0.001 0.00 0.00
10 40.50 5.0 1.831 0.96 0.09
11 45.50 5.0 0.001 0.00 0.00
12 50.50 5.0 0.001 0.00 0.00
----------------------------------------------
Shamoto et al.
=================
Total ground surface settlement = 0.24 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
5 14.50 2.0 0.000 0.00 0.00
6 18.50 6.0 3.705 1.00 0.22
7 24.75 6.5 0.000 0.00 0.00
8 30.50 5.0 0.000 0.00 0.00
9 35.50 5.0 0.000 0.00 0.00
10 40.50 5.0 0.500 0.85 0.02
11 45.50 5.0 0.000 0.00 0.00
12 50.50 5.0 0.000 0.00 0.00
----------------------------------------------
Wu & Seed
=================
Total ground surface settlement = 0.29 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
5 14.50 2.0 0.000 0.00 0.00
6
6 18.50 6.0 3.855 1.00 0.23
7 24.75 6.5 0.003 0.00 0.00
8 30.50 5.0 0.003 0.00 0.00
9 35.50 5.0 0.000 0.00 0.00
10 40.50 5.0 1.356 0.92 0.06
11 45.50 5.0 0.000 0.00 0.00
12 50.50 5.0 0.000 0.00 0.00
----------------------------------------------
7
Liquefaction Hazard Evaluation Report
by WSLiq Program beta (May, 2009)
---------------------------------------------------
Site Name: Cedar River Apartments - Renton, WA (B4)
Site Location (N,W) = 47.480 , 122.194
Job No: 81175025
Analyst: Koehn
Date: 7/26/2017 9:01:05 AM
---------------------------------------------------
=== Soil Profile ===
Unit: ft
The number of soil layers: 12
GWT at top of layer: 4
GWT depth: 9.50
SPT Energy Ratio (%): 100.40
Amplification Factors: a= -0.1500 b= -0.1300
Elevation: 43.00
Ground Surface: Infinite Slope (%)= 4.2
Layer Descpt. Thickness Unit Weight Nm N160 Vs
(ft) (lb/ft3) ft/sec
1 SILTY_SAND_-_FILL_(SM) 4.5 120.00 22 62.6 939.0
2 SILTY_SAND_-_FILL_(SM) 2.5 120.00 24 68.3 963.0
3 SILTY_SAND_-_FILL_(SM) 2.5 120.00 4 9.8 572.7
4 SILTY_SAND_-_FILL_(SM) 3.5 120.00 52 113.6 1205.0
5 SAND_W/_SILT_&_GRAVEL_(SW-SM) 5 130.00 25 49.5 974.4
6 SAND_W/_SILT_&_GRAVEL_(SW-SM) 5 130.00 100 179.0 1456.6
7 SAND_W/_SILT_&_GRAVEL_(SW-SM) 5 130.00 100 164.6 1456.6
8 GRAVEL_W/_SILT_&_SAND_(GW-GM) 5 130.00 58 88.9 1243.8
9 GRAVEL_W/_SILT_&_SAND_(GW-GM) 5 130.00 100 143.9 1456.6
10 GRAVEL_W/_SILT_&_SAND_(GW-GM) 5 130.00 100 136.1 1456.6
11 GRAVEL_W/_SILT_&_SAND_(GW) 5 130.00 14 18.1 823.6
12 GRAVEL_W/_SILT_&_SAND_(GW) 3.5 130.00 34 42.3 1065.3
Layer FC PI wc/LL D50 Ini. Eff. Ini. Total
(%) (mm) Stress (psf) Stress (psf)
1 20 Unsat Unsat 1.000 270.0 270.00
2 20 Unsat Unsat 1.000 690.0 690.00
3 7 Unsat Unsat 1.000 990.0 990.00
4 7 0 1 1.000 1240.8 1350.00
5 10 0 1 10.000 1510.6 1885.00
6 10 0 1 10.000 1848.6 2535.00
7 10 0 1 10.000 2186.6 3185.00
8 10 0 1 10.000 2524.6 3835.00
9 6 0 1 10.000 2862.6 4485.00
10 6 0 1 10.000 3200.6 5135.00
11 16 0 1 10.000 3538.6 5785.00
12 0 N.P. N.P. 10.000 3825.9 6337.50
Soil Profile Plots
1
=== Initiation ===
---------------------------------------------------
Initiation - Multiple Scenario
-----------------------------------------
Retrun Period (yrs) = 2475.0
Models Selected :
Use All Deterministic Models.
--WSDOT Recommended--
Use NCEER, Boulanger & Idriss, and
Cetin's model with weighting factors
of 0.4, 0.4, and 0.2 respectively.
-----------------------------------------
===== Mean Mw and FS ==============
---NCEER Model------------
--- PGA = 0.578 Mw = 6.67---------
2
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
4 113.64 0.280 3.000 10.71 23.6
5 49.51 0.315 3.000 9.53 25.2
6 179.04 0.336 3.000 8.92 26.0
7 164.62 0.345 3.000 8.70 26.4
8 88.86 0.345 3.000 8.71 26.3
9 143.87 0.337 3.000 8.90 26.1
10 136.07 0.324 3.000 9.25 25.6
11 18.12 0.308 0.208 0.68 24.9
12 42.31 0.295 3.000 10.19 24.3
===== Mean Mw and FS ==============
---Boulanger and Idriss Model------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
4 46.00 0.321 3.000 9.35 26.0
5 45.74 0.360 3.000 8.32 27.3
6 46.00 0.385 3.000 7.79 27.9
7 46.00 0.397 3.000 7.56 28.1
8 46.00 0.400 3.000 7.50 28.2
9 46.00 0.398 3.000 7.53 28.1
10 46.00 0.393 3.000 7.63 28.0
11 18.56 0.386 0.218 0.56 27.7
12 46.00 0.378 3.000 7.93 27.5
===== Mean Mw and FS ==============
---Cetin et al. Model------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
4 113.64 0.409 3.000 7.34 23.5
5 49.51 0.469 2.829 6.03 25.5
6 179.04 0.515 3.000 5.82 27.5
7 164.62 0.547 3.000 5.48 28.8
8 88.86 0.571 3.000 5.26 29.9
9 143.87 0.589 3.000 5.10 31.4
10 136.07 0.603 3.000 4.98 32.1
11 18.12 0.614 0.224 0.36 31.0
12 42.31 0.622 1.163 1.87 34.3
---WSDOT Recommended------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
4 113.64 0.322 3.000 9.31 24.5
5 49.51 0.364 2.966 8.15 26.1
6 179.04 0.392 3.000 7.66 27.1
7 164.62 0.406 3.000 7.39 27.6
8 88.86 0.412 3.000 7.28 27.8
9 143.87 0.412 3.000 7.28 28.0
10 136.07 0.407 3.000 7.36 27.8
11 18.12 0.400 0.215 0.54 27.3
12 42.31 0.394 2.633 6.69 27.6
Table of FS
---------------------------------------
# Depth NCEER B&I Cetin WSDOT
3
ft PL=0.60 PL=0.60
4 -11.25 10.71 9.35 7.34 9.31
5 -15.50 9.53 8.32 6.03 8.15
6 -20.50 8.92 7.79 5.82 7.66
7 -25.50 8.70 7.56 5.48 7.39
8 -30.50 8.71 7.50 5.26 7.28
9 -35.50 8.90 7.53 5.10 7.28
10 -40.50 9.25 7.63 4.98 7.36
11 -45.50 0.68 0.56 0.36 0.54
12 -49.75 10.19 7.93 1.87 6.69
=== Effects ===
---------------------------------------------------
** Lateral Spreading **
(Infinite Slope: 4.2%)
-----------------------
>>>Multiple Scenario Results
Model Selected :
WSDOT Recommended (weighted average)
using models of Baska & Kramer and Youd et al.
-----------------------------------------
Baska & Kramer: 2.83 ft
Youd et al.: 0.00 ft (Notice: T15 = 0)
Idriss & Boulanger: 1.14 ft
----------------------------------------
Weighting factors: Baska and Kramer = 0.65
Youd et al. = 0.35
WSDOT Recommended: 1.84 ft
4
** Lateral Spreading **
(Free-Face Slope: 12.8%)
-----------------------
>>>Multiple Scenario Results
Model Selected :
WSDOT Recommended (weighted average)
using models of Baska & Kramer and Youd et al.
-----------------------------------------
Baska & Kramer: 1.52 ft
Youd et al.: 0.00 ft (Notice: T15 = 0)
Idriss & Boulanger: 0.30 ft
----------------------------------------
Weighting factors: Baska and Kramer = 0.65
Youd et al. = 0.35
WSDOT Recommended: 0.99 ft
=== Effects ===
---------------------------------------------------
** Settlement **
----------------
>>>Multiple Scenario Results
Groud Surface Settlement MULTIPLE Scenario
Return Period (yrs) = 2475.0
Model Selected :
5
Use all deterministic models.
-----------------------------------------
Tokimatsu & Seed
=================
Total ground surface settlement = 0.06 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
4 11.25 3.5 0.001 0.00 0.00
5 15.50 5.0 0.001 0.00 0.00
6 20.50 5.0 0.001 0.00 0.00
7 25.50 5.0 0.001 0.00 0.00
8 30.50 5.0 0.001 0.00 0.00
9 35.50 5.0 0.001 0.00 0.00
10 40.50 5.0 0.001 0.00 0.00
11 45.50 5.0 1.181 1.00 0.06
12 49.75 3.5 0.001 0.00 0.00
----------------------------------------------
Ishihara & Yoshimine
=================
Total ground surface settlement = 0.11 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
4 11.25 3.5 0.001 0.00 0.00
5 15.50 5.0 0.001 0.00 0.00
6 20.50 5.0 0.001 0.00 0.00
7 25.50 5.0 0.001 0.00 0.00
8 30.50 5.0 0.001 0.00 0.00
9 35.50 5.0 0.001 0.00 0.00
10 40.50 5.0 0.001 0.00 0.00
11 45.50 5.0 2.304 0.98 0.11
12 49.75 3.5 0.001 0.00 0.00
----------------------------------------------
Shamoto et al.
=================
Total ground surface settlement = 0.03 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
4 11.25 3.5 0.000 0.00 0.00
5 15.50 5.0 0.000 0.00 0.00
6 20.50 5.0 0.000 0.00 0.00
7 25.50 5.0 0.000 0.00 0.00
8 30.50 5.0 0.000 0.00 0.00
9 35.50 5.0 0.000 0.00 0.00
10 40.50 5.0 0.000 0.00 0.00
11 45.50 5.0 0.586 0.90 0.03
12 49.75 3.5 0.000 0.00 0.00
----------------------------------------------
Wu & Seed
=================
Total ground surface settlement = 0.07 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
6
4 11.25 3.5 0.000 0.00 0.00
5 15.50 5.0 0.000 0.00 0.00
6 20.50 5.0 0.000 0.00 0.00
7 25.50 5.0 0.000 0.00 0.00
8 30.50 5.0 0.000 0.00 0.00
9 35.50 5.0 0.000 0.00 0.00
10 40.50 5.0 0.000 0.00 0.00
11 45.50 5.0 1.511 0.94 0.07
12 49.75 3.5 0.003 0.00 0.00
----------------------------------------------
7
Liquefaction Hazard Evaluation Report
by WSLiq Program beta (May, 2009)
---------------------------------------------------
Site Name: Cedar River Apartments - Renton, WA (B5)
Site Location (N,W) = 47.480 , 122.194
Job No: 81175025
Analyst: Koehn
Date: 7/26/2017 9:02:56 AM
---------------------------------------------------
=== Soil Profile ===
Unit: ft
The number of soil layers: 14
GWT at top of layer: 5
GWT depth: 11.50
SPT Energy Ratio (%): 100.40
Amplification Factors: a= -0.1500 b= -0.1300
Elevation: 44.50
Ground Surface: Infinite Slope (%)= 2.4
Layer Descpt. Thickness Unit Weight Nm N160 Vs
(ft) (lb/ft3) ft/sec
1 SILTY_SAND_-_FILL_(SM) 4.5 120.00 56 159.3 1231.2
2 SILTY_SAND_-_FILL_(SM) 2.5 120.00 22 62.6 939.0
3 SILT_W/_SAND_(ML) 2.5 120.00 3 7.3 526.9
4 SILT_W/_SAND_(ML) 2.0 120.00 7 15.2 673.6
5 GRAVEL_W/_SAND_(GW) 6.5 130.00 27 52.0 996.4
6 GRAVEL_W/_SAND_(GW) 5 130.00 8 13.8 700.2
7 GRAVEL_W/_SAND_(GW) 5 130.00 9 14.4 724.6
8 GRAVEL_W/_SAND_(GW) 5 130.00 32 47.7 1046.8
9 GRAVEL_W/_SAND_(GW) 5 130.00 21 29.5 926.4
10 GRAVEL_W/_SAND_(GW) 5 130.00 29 38.6 1017.3
11 GRAVEL_W/_SAND_(GW) 5 130.00 30 38.1 1027.3
12 GRAVEL_W/_SAND_(GW) 5 130.00 30 36.4 1027.3
13 GRAVEL_W/_SAND_(GW) 5 130.00 58 67.7 1243.8
14 GRAVEL_W/_SAND_(GW) 3.5 130.00 100 113.0 1456.6
Layer FC PI wc/LL D50 Ini. Eff. Ini. Total
(%) (mm) Stress (psf) Stress (psf)
1 20 Unsat Unsat 1.000 270.0 270.00
2 20 Unsat Unsat 1.000 690.0 690.00
3 68 Unsat Unsat 1.000 990.0 990.00
4 68 Unsat Unsat 1.000 1260.0 1260.00
5 4 0 1 10.000 1599.7 1802.50
6 4 0 1 10.000 1988.4 2550.00
7 3 0 1 10.000 2326.4 3200.00
8 3 0 1 10.000 2664.4 3850.00
9 3 0 1 10.000 3002.4 4500.00
10 1 0 1 10.000 3340.4 5150.00
11 1 0 1 10.000 3678.4 5800.00
12 1 0 1.5 10.000 4016.4 6450.00
13 1 0 1.5 10.000 4354.4 7100.00
14 1 0 1.5 10.000 4641.7 7652.50
Soil Profile Plots
1
=== Initiation ===
---------------------------------------------------
Initiation - Multiple Scenario
-----------------------------------------
Retrun Period (yrs) = 2475.0
Models Selected :
Use All Deterministic Models.
--WSDOT Recommended--
Use NCEER, Boulanger & Idriss, and
Cetin's model with weighting factors
of 0.4, 0.4, and 0.2 respectively.
-----------------------------------------
===== Mean Mw and FS ==============
---NCEER Model------------
--- PGA = 0.578 Mw = 6.67---------
2
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
5 51.96 0.285 3.000 10.52 23.8
6 13.81 0.314 0.148 0.47 25.2
7 14.36 0.326 0.150 0.46 25.6
8 47.72 0.328 3.000 9.15 25.7
9 29.50 0.322 0.386 1.20 25.5
10 38.62 0.311 3.000 9.63 25.0
11 38.08 0.297 3.000 10.08 24.4
12 36.44 0.283 3.000 10.62 23.7
13 67.66 0.269 3.000 11.16 23.0
14 112.99 0.259 3.000 11.59 22.4
===== Mean Mw and FS ==============
---Boulanger and Idriss Model------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
5 46.00 0.327 3.000 9.18 26.2
6 13.81 0.360 0.146 0.41 27.2
7 14.37 0.375 0.149 0.40 27.6
8 46.00 0.381 3.000 7.88 27.7
9 31.02 0.381 0.515 1.35 27.7
10 42.66 0.378 3.000 7.94 27.6
11 42.99 0.372 3.000 8.06 27.4
12 41.75 0.365 3.000 8.23 27.1
13 46.00 0.356 3.000 8.42 26.8
14 46.00 0.349 3.000 8.60 26.6
===== Mean Mw and FS ==============
---Cetin et al. Model------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
5 51.96 0.421 2.912 6.92 25.2
6 13.81 0.477 0.169 0.36 27.6
7 14.36 0.507 0.168 0.33 29.2
8 47.72 0.526 2.017 3.83 30.2
9 29.50 0.536 0.494 0.92 30.8
10 38.62 0.536 0.930 1.73 31.6
11 38.08 0.530 0.868 1.64 31.8
12 36.44 0.519 0.749 1.44 31.8
13 67.66 0.506 3.000 5.93 31.8
14 112.99 0.496 3.000 6.05 31.8
---WSDOT Recommended------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
5 51.96 0.329 2.982 9.07 25.1
6 13.81 0.365 0.152 0.42 26.5
7 14.36 0.382 0.153 0.40 27.1
8 47.72 0.389 2.803 7.21 27.4
9 29.50 0.388 0.459 1.18 27.4
10 38.62 0.383 2.586 6.75 27.4
11 38.08 0.374 2.574 6.88 27.1
12 36.44 0.363 2.550 7.03 26.7
13 67.66 0.351 3.000 8.54 26.3
14 112.99 0.342 3.000 8.77 25.9
3
Table of FS
---------------------------------------
# Depth NCEER B&I Cetin WSDOT
ft PL=0.60 PL=0.60
5 -14.75 10.52 9.18 6.92 9.07
6 -20.50 0.47 0.41 0.36 0.42
7 -25.50 0.46 0.40 0.33 0.40
8 -30.50 9.15 7.88 3.83 7.21
9 -35.50 1.20 1.35 0.92 1.18
10 -40.50 9.63 7.94 1.73 6.75
11 -45.50 10.08 8.06 1.64 6.88
12 -50.50 10.62 8.23 1.44 7.03
13 -55.50 11.16 8.42 5.93 8.54
14 -59.75 11.59 8.60 6.05 8.77
=== Effects ===
---------------------------------------------------
** Lateral Spreading **
(Infinite Slope: 2.4%)
-----------------------
>>>Multiple Scenario Results
Model Selected :
WSDOT Recommended (weighted average)
using models of Baska & Kramer and Youd et al.
-----------------------------------------
Baska & Kramer: 2.32 ft
Youd et al.: 0.36 ft
Idriss & Boulanger: 8.05 ft
----------------------------------------
Weighting factors: Baska and Kramer = 0.65
Youd et al. = 0.35
WSDOT Recommended: 1.64 ft
4
** Lateral Spreading **
(Free-Face Slope: 21.6%)
-----------------------
>>>Multiple Scenario Results
Model Selected :
WSDOT Recommended (weighted average)
using models of Baska & Kramer and Youd et al.
-----------------------------------------
Baska & Kramer: 3.35 ft
Youd et al.: 0.53 ft
Idriss & Boulanger: 5.45 ft
----------------------------------------
Weighting factors: Baska and Kramer = 0.65
Youd et al. = 0.35
WSDOT Recommended: 2.36 ft
=== Effects ===
---------------------------------------------------
** Settlement **
----------------
>>>Multiple Scenario Results
Groud Surface Settlement MULTIPLE Scenario
Return Period (yrs) = 2475.0
Model Selected :
5
Use all deterministic models.
-----------------------------------------
Tokimatsu & Seed
=================
Total ground surface settlement = 0.20 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
5 14.75 6.5 0.001 0.00 0.00
6 20.50 5.0 2.022 0.98 0.10
7 25.50 5.0 1.954 1.00 0.10
8 30.50 5.0 0.001 0.00 0.00
9 35.50 5.0 0.306 0.40 0.01
10 40.50 5.0 0.001 0.00 0.00
11 45.50 5.0 0.001 0.00 0.00
12 50.50 5.0 0.001 0.00 0.00
13 55.50 5.0 0.001 0.00 0.00
14 59.75 3.5 0.001 0.00 0.00
----------------------------------------------
Ishihara & Yoshimine
=================
Total ground surface settlement = 0.31 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
5 14.75 6.5 0.001 0.00 0.00
6 20.50 5.0 3.115 0.99 0.15
7 25.50 5.0 3.028 1.00 0.15
8 30.50 5.0 0.001 0.00 0.00
9 35.50 5.0 0.414 0.32 0.01
10 40.50 5.0 0.001 0.00 0.00
11 45.50 5.0 0.001 0.00 0.00
12 50.50 5.0 0.001 0.00 0.00
13 55.50 5.0 0.001 0.00 0.00
14 59.75 3.5 0.001 0.00 0.00
----------------------------------------------
Shamoto et al.
=================
Total ground surface settlement = 0.16 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
5 14.75 6.5 0.000 0.00 0.00
6 20.50 5.0 1.674 0.99 0.08
7 25.50 5.0 1.537 1.00 0.08
8 30.50 5.0 0.000 0.00 0.00
9 35.50 5.0 0.000 0.16 0.00
10 40.50 5.0 0.000 0.00 0.00
11 45.50 5.0 0.000 0.00 0.00
12 50.50 5.0 0.000 0.00 0.00
13 55.50 5.0 0.000 0.00 0.00
14 59.75 3.5 0.000 0.00 0.00
----------------------------------------------
Wu & Seed
=================
Total ground surface settlement = 0.28 ft
----------------------------------------------
6
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
5 14.75 6.5 0.000 0.00 0.00
6 20.50 5.0 2.743 0.98 0.13
7 25.50 5.0 2.681 0.99 0.13
8 30.50 5.0 0.000 0.00 0.00
9 35.50 5.0 0.731 0.23 0.01
10 40.50 5.0 0.029 0.00 0.00
11 45.50 5.0 0.028 0.00 0.00
12 50.50 5.0 0.065 0.00 0.00
13 55.50 5.0 0.000 0.00 0.00
14 59.75 3.5 0.000 0.00 0.00
----------------------------------------------
7
Liquefaction Hazard Evaluation Report
by WSLiq Program beta (May, 2009)
---------------------------------------------------
Site Name: Cedar River Apartments - Renton, WA (B6)
Site Location (N,W) = 47.480 , 122.194
Job No: 81175025
Analyst: Koehn
Date: 7/26/2017 4:42:15 PM
---------------------------------------------------
=== Soil Profile ===
Unit: ft
The number of soil layers: 11
GWT at top of layer: 7
GWT depth: 21.00
SPT Energy Ratio (%): 77.00
Amplification Factors: a= -0.1500 b= -0.1300
Elevation: 52.00
Ground Surface: Infinite Slope (%)= 3.8
Layer Descpt. Thickness Unit Weight Nm N160 Vs
(ft) (lb/ft3) ft/sec
1 SILTY_SAND_-_FILL_(SM) 4.5 120.00 36 78.5 1002.9
2 SILTY_SAND_-_FILL_(SM) 2.5 120.00 46 100.4 1076.8
3 SAND_W/_SILT_(SP-SM) 2.5 120.00 23 43.2 880.7
4 SAND_W/_SILT_(SP-SM) 3.5 120.00 12 19.3 729.3
5 SANDY_SILT_(ML) 3.5 120.00 10 14.0 691.7
6 SAND_(SP) 4.5 120.00 7 8.7 623.8
7 SILTY_SAND_(SM) 2 120.00 7 8.1 623.8
8 SILTY_SAND_(SM) 5 120.00 13 14.6 746.4
9 GRAVEL_W/_SILT_&_SAND_(GW-GM) 5 130.00 25 26.5 902.3
10 GRAVEL_W/_SILT_&_SAND_(GW-GM) 4 130.00 60 60.8 1163.0
11 GRAVEL_W/_SILT_&_SAND_(GW-GM) 2.5 130.00 80 78.5 1264.2
Layer FC PI wc/LL D50 Ini. Eff. Ini. Total
(%) (mm) Stress (psf) Stress (psf)
1 20 Unsat Unsat 1.000 270.0 270.00
2 20 Unsat Unsat 1.000 690.0 690.00
3 9 Unsat Unsat 1.000 990.0 990.00
4 9 Unsat Unsat 1.000 1350.0 1350.00
5 67 Unsat Unsat 0.100 1770.0 1770.00
6 0 Unsat Unsat 1.000 2250.0 2250.00
7 47 0 1 1.000 2577.6 2640.00
8 47 0 1 1.000 2779.2 3060.00
9 9 0 1 10.000 3092.2 3685.00
10 9 0 1 10.000 3396.4 4270.00
11 9 0 1 10.000 3616.1 4692.50
Soil Profile Plots
1
=== Initiation ===
---------------------------------------------------
Initiation - Multiple Scenario
-----------------------------------------
Retrun Period (yrs) = 2475.0
Models Selected :
Use All Deterministic Models.
--WSDOT Recommended--
Use NCEER, Boulanger & Idriss, and
Cetin's model with weighting factors
of 0.4, 0.4, and 0.2 respectively.
-----------------------------------------
===== Mean Mw and FS ==============
---NCEER Model------------
2
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
7 8.14 0.249 0.152 0.61 21.8
8 14.56 0.261 0.233 0.89 22.5
9 26.54 0.270 0.313 1.16 23.0
10 60.78 0.272 3.000 11.03 23.1
11 78.54 0.270 3.000 11.11 23.0
===== Mean Mw and FS ==============
---Boulanger and Idriss Model------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
7 8.03 0.285 0.142 0.50 24.4
8 14.60 0.300 0.201 0.67 25.1
9 27.79 0.314 0.378 1.20 25.6
10 46.00 0.321 3.000 9.35 25.8
11 46.00 0.323 3.000 9.28 25.9
===== Mean Mw and FS ==============
---Cetin et al. Model------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
7 8.14 0.378 0.134 0.35 20.1
8 14.56 0.404 0.232 0.57 21.0
9 26.54 0.430 0.420 0.98 27.1
10 60.78 0.444 2.999 6.76 27.9
11 78.54 0.449 3.000 6.68 28.3
---WSDOT Recommended------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
7 8.14 0.289 0.144 0.50 22.5
8 14.56 0.305 0.220 0.72 23.2
9 26.54 0.320 0.360 1.13 24.9
10 60.78 0.326 3.000 9.20 25.2
11 78.54 0.327 3.000 9.17 25.2
Table of FS
---------------------------------------
# Depth NCEER B&I Cetin WSDOT
ft PL=0.60 PL=0.60
7 -22.00 0.61 0.50 0.35 0.50
8 -25.50 0.89 0.67 0.57 0.72
9 -30.50 1.16 1.20 0.98 1.13
10 -35.00 11.03 9.35 6.76 9.20
11 -38.25 11.11 9.28 6.68 9.17
3
=== Effects ===
---------------------------------------------------
** Lateral Spreading **
(Infinite Slope: 3.8%)
-----------------------
>>>Multiple Scenario Results
Model Selected :
WSDOT Recommended (weighted average)
using models of Baska & Kramer and Youd et al.
-----------------------------------------
Baska & Kramer: 2.55 ft
Youd et al.: 0.14 ft
Idriss & Boulanger: 1.57 ft
----------------------------------------
Weighting factors: Baska and Kramer = 0.65
Youd et al. = 0.35
WSDOT Recommended: 1.71 ft
4
** Lateral Spreading **
(Free-Face Slope: 7.1%)
-----------------------
>>>Multiple Scenario Results
Model Selected :
WSDOT Recommended (weighted average)
using models of Baska & Kramer and Youd et al.
-----------------------------------------
Baska & Kramer: 0.85 ft
Youd et al.: 0.09 ft
Idriss & Boulanger: 0.28 ft
----------------------------------------
Weighting factors: Baska and Kramer = 0.65
Youd et al. = 0.35
WSDOT Recommended: 0.58 ft
=== Effects ===
---------------------------------------------------
** Settlement **
----------------
>>>Multiple Scenario Results
Groud Surface Settlement MULTIPLE Scenario
Return Period (yrs) = 2475.0
Model Selected :
5
Use all deterministic models.
-----------------------------------------
Tokimatsu & Seed
=================
Total ground surface settlement = 0.09 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
7 22.00 2.0 1.761 1.00 0.04
8 25.50 5.0 0.924 0.99 0.05
9 30.50 5.0 0.202 0.60 0.01
10 35.00 4.0 0.001 0.00 0.00
11 38.25 2.5 0.001 0.00 0.00
----------------------------------------------
Ishihara & Yoshimine
=================
Total ground surface settlement = 0.19 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
7 22.00 2.0 3.998 0.98 0.08
8 25.50 5.0 2.231 0.94 0.10
9 30.50 5.0 0.527 0.32 0.01
10 35.00 4.0 0.001 0.00 0.00
11 38.25 2.5 0.001 0.00 0.00
----------------------------------------------
Shamoto et al.
=================
Total ground surface settlement = 0.20 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
7 22.00 2.0 5.547 0.96 0.11
8 25.50 5.0 2.116 0.85 0.09
9 30.50 5.0 0.506 0.17 0.00
10 35.00 4.0 0.000 0.00 0.00
11 38.25 2.5 0.000 0.00 0.00
----------------------------------------------
Wu & Seed
=================
Total ground surface settlement = 0.10 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
7 22.00 2.0 2.277 0.95 0.04
8 25.50 5.0 1.227 0.84 0.05
9 30.50 5.0 0.717 0.24 0.01
10 35.00 4.0 0.000 0.00 0.00
11 38.25 2.5 0.000 0.00 0.00
----------------------------------------------
6
7
Liquefaction Hazard Evaluation Report
by WSLiq Program beta (May, 2009)
---------------------------------------------------
Site Name: Cedar River Apartments - Renton, WA (B7)
Site Location (N,W) = 47.480 , 122.194
Job No: 81175025
Analyst: Koehn
Date: 7/26/2017 4:52:19 PM
---------------------------------------------------
=== Soil Profile ===
Unit: ft
The number of soil layers: 10
GWT at top of layer: 5
GWT depth: 13.00
SPT Energy Ratio (%): 100.40
Amplification Factors: a= -0.1500 b= -0.1300
Elevation: 50.00
Ground Surface: Infinite Slope (%)= 3.4
Layer Descpt. Thickness Unit Weight Nm N160 Vs
(ft) (lb/ft3) ft/sec
1 SILTY_SAND_W/_GRAVEL_(SM) 4.5 120.00 40 113.8 1116.7
2 SILTY_SAND_W/_GRAVEL_(SM) 2.5 120.00 31 88.2 1037.2
3 SILTY_SAND_W/_GRAVEL_(SM) 2.5 120.00 42 102.8 1132.6
4 SILTY_SAND_W/_GRAVEL_(SM) 3.5 120.00 43 90.1 1140.4
5 SAND_(SP) 5 120.00 25 46.6 974.4
6 SILTY_SAND_(SM) 5 120.00 26 44.8 985.6
7 GRAVEL_W/_SAND_(GP) 5 130.00 33 52.9 1056.1
8 GRAVEL_W/_SAND_(GP) 5 130.00 58 86.8 1243.8
9 GRAVEL_W/_SAND_(GP) 5 130.00 30 42.3 1027.3
10 GRAVEL_W/_SAND_(GP) 3.5 130.00 60 80.8 1256.1
Layer FC PI wc/LL D50 Ini. Eff. Ini. Total
(%) (mm) Stress (psf) Stress (psf)
1 13 Unsat Unsat 1.000 270.0 270.00
2 13 Unsat Unsat 1.000 690.0 690.00
3 13 Unsat Unsat 1.000 990.0 990.00
4 13 Unsat Unsat 1.000 1350.0 1350.00
5 0 N.P. N.P. 0.100 1704.0 1860.00
6 25 0 1 1.000 1992.0 2460.00
7 2 0 1 1.000 2305.0 3085.00
8 2 0 1 1.000 2643.0 3735.00
9 2 0 1 10.000 2981.0 4385.00
10 2 0 1 10.000 3268.3 4937.50
Soil Profile Plots
1
=== Initiation ===
---------------------------------------------------
Initiation - Multiple Scenario
-----------------------------------------
Retrun Period (yrs) = 2475.0
Models Selected :
Use All Deterministic Models.
--WSDOT Recommended--
Use NCEER, Boulanger & Idriss, and
Cetin's model with weighting factors
of 0.4, 0.4, and 0.2 respectively.
-----------------------------------------
===== Mean Mw and FS ==============
---NCEER Model------------
--- PGA = 0.578 Mw = 6.67---------
2
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
5 46.62 0.275 3.000 10.90 23.3
6 44.84 0.303 3.000 9.91 24.7
7 52.91 0.317 3.000 9.46 25.3
8 86.84 0.321 3.000 9.36 25.4
9 42.30 0.316 3.000 9.48 25.3
10 80.79 0.308 3.000 9.73 24.9
===== Mean Mw and FS ==============
---Boulanger and Idriss Model------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
5 44.38 0.315 3.000 9.52 25.8
6 44.23 0.347 3.000 8.65 26.8
7 46.00 0.364 3.000 8.23 27.3
8 46.00 0.372 3.000 8.06 27.5
9 45.86 0.374 3.000 8.02 27.5
10 46.00 0.372 3.000 8.06 27.4
===== Mean Mw and FS ==============
---Cetin et al. Model------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
5 46.62 0.410 1.993 4.86 25.7
6 44.84 0.464 2.482 5.35 24.3
7 52.91 0.503 2.813 5.60 29.2
8 86.84 0.530 3.000 5.66 30.4
9 42.30 0.552 1.286 2.33 31.4
10 80.79 0.566 3.000 5.30 32.1
---WSDOT Recommended------------
--- PGA = 0.578 Mw = 6.67---------
Layer (N1)60 CSR CRR FS Nreq
----- ------ ------ ------ ------ ------
5 46.62 0.318 2.799 8.79 24.8
6 44.84 0.353 2.896 8.21 25.5
7 52.91 0.373 2.963 7.94 26.9
8 86.84 0.383 3.000 7.83 27.3
9 42.30 0.386 2.657 6.88 27.4
10 80.79 0.385 3.000 7.78 27.3
Table of FS
---------------------------------------
# Depth NCEER B&I Cetin WSDOT
ft PL=0.60 PL=0.60
5 -15.50 10.90 9.52 4.86 8.79
6 -20.50 9.91 8.65 5.35 8.21
7 -25.50 9.46 8.23 5.60 7.94
8 -30.50 9.36 8.06 5.66 7.83
9 -35.50 9.48 8.02 2.33 6.88
10 -39.75 9.73 8.06 5.30 7.78
3
=== Effects ===
---------------------------------------------------
** Lateral Spreading **
(Inifinite Slope: 3.4%)
-----------------------
>>>Multiple Scenario Results
Model Selected :
WSDOT Recommended (weighted average)
using models of Baska & Kramer and Youd et al.
-----------------------------------------
Baska & Kramer: 2.13 ft
Youd et al.: 0.00 ft (Notice: T15 = 0)
Idriss & Boulanger: 0.10 ft
----------------------------------------
Weighting factors: Baska and Kramer = 0.65
Youd et al. = 0.35
WSDOT Recommended: 1.39 ft
4
** Lateral Spreading **
(Free-Face Slope: 5.1%)
-----------------------
>>>Multiple Scenario Results
Model Selected :
WSDOT Recommended (weighted average)
using models of Baska & Kramer and Youd et al.
-----------------------------------------
Baska & Kramer: 0.47 ft
Youd et al.: 0.00 ft (Notice: T15 = 0)
Idriss & Boulanger: 0.02 ft
----------------------------------------
Weighting factors: Baska and Kramer = 0.65
Youd et al. = 0.35
WSDOT Recommended: 0.31 ft
=== Effects ===
---------------------------------------------------
** Settlement **
----------------
>>>Multiple Scenario Results
Groud Surface Settlement MULTIPLE Scenario
Return Period (yrs) = 2475.0
Model Selected :
Use all deterministic models.
5
-----------------------------------------
Tokimatsu & Seed
=================
Total ground surface settlement = 0.00 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
5 15.50 5.0 0.001 0.00 0.00
6 20.50 5.0 0.001 0.00 0.00
7 25.50 5.0 0.001 0.00 0.00
8 30.50 5.0 0.001 0.00 0.00
9 35.50 5.0 0.001 0.00 0.00
10 39.75 3.5 0.001 0.00 0.00
----------------------------------------------
Ishihara & Yoshimine
=================
Total ground surface settlement = 0.00 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
5 15.50 5.0 0.001 0.00 0.00
6 20.50 5.0 0.001 0.00 0.00
7 25.50 5.0 0.001 0.00 0.00
8 30.50 5.0 0.001 0.00 0.00
9 35.50 5.0 0.001 0.00 0.00
10 39.75 3.5 0.001 0.00 0.00
----------------------------------------------
Shamoto et al.
=================
Total ground surface settlement = 0.00 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
5 15.50 5.0 0.000 0.00 0.00
6 20.50 5.0 0.000 0.00 0.00
7 25.50 5.0 0.000 0.00 0.00
8 30.50 5.0 0.000 0.00 0.00
9 35.50 5.0 0.000 0.00 0.00
10 39.75 3.5 0.000 0.00 0.00
----------------------------------------------
Wu & Seed
=================
Total ground surface settlement = 0.00 ft
----------------------------------------------
# Depth thickness ev Weight dh
ft ft % ft
----------------------------------------------
5 15.50 5.0 0.000 0.00 0.00
6 20.50 5.0 0.000 0.00 0.00
7 25.50 5.0 0.000 0.00 0.00
8 30.50 5.0 0.000 0.00 0.00
9 35.50 5.0 0.003 0.00 0.00
10 39.75 3.5 0.000 0.00 0.00
----------------------------------------------
6
7