HomeMy WebLinkAboutRS_Geotech_Report_230905_v1Geotechnical & Earthquake
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GEOTECHNICAL REPORT
PROPOSED OFFICE AND SHOP BUILDING
1404 SW GRADY WAY
RENTON, WASHINGTON
Project No. 23-164
July 2023
Prepared for:
1404 Grady LLC
3213 Eastlake Avenue East, Ste B
Seattle, Washington 98102-3513
Tel: 206.262.0370 www.pangeoinc.com
________________________________________________
3213 Eastlake Ave E, Ste B
Seattle, WA 98102
Tel:(206) 262-0370
www.pangeoinc.com
Geotechnical & Earthquake
Engineering Consultants
July 12, 2023
File No. 23-164
1404 Grady LLC
1404 SW Grady Way, Renton, WA 98055
Attn: Drew Beebe
Subject: GEOTECHNICAL REPORT
PROPOSED OFFICE AND SHOP BUILDING
1404 SW GRADY WAY, RENTON, WASHINGTON
Dear Drew,
Please find attached our geotechnical report for the proposed building project at the above-
referenced site in Renton, Washington. This report documents the subsurface conditions at the site
and our geotechnical engineering recommendations for the proposed project.
In summary, our test borings PG-1 and PG-2 drilled at the site encountered fill overlying very
loose to medium dense alluvial soils up to about 71.5 feet below the surface. Based on the borings
drilled and our experience with the soil conditions in the area, this alluvium unit may likely extend
to about 80 to 100 feet below the surface. The site soil is considered susceptible to seismically-
induced liquefaction under IBC-code level earthquakes, and relatively large ground settlement
could occur as a result of soil liquefaction during the design seismic event. To mitigate the potential
impacts to the proposed building due to the risk of estimated differential settlements, it is our
opinion that the proposed building should be supported by a mat foundation/structural slab with
thickened edges bearing on a minimum of 12 inches of compacted structural fill placed over a
layer of geogrid.
We appreciate the opportunity to work with you on this project. Please call if there are any
questions regarding this report.
Sincerely,
H. Michael Xue, P.E.
Principal Geotechnical Engineer
Encl: Geotechnical Report
i
TABLE OF CONTENTS
1.0 INTRODUCTION................................................................................................................... 1
2.0 SITE AND PROJECT DESCRIPTION ............................................................................... 1
3.0 FIELD EXPLORATIONS ..................................................................................................... 2
4.0 SITE GEOLOGY AND SUBSURFACE CONDITIONS .................................................... 2
4.1 SITE GEOLOGY ....................................................................................................................... 2
4.2 SOILS ..................................................................................................................................... 2
4.3 GROUNDWATER ..................................................................................................................... 3
5.0 GEOLOGICALLY HAZARDOUS AREAS EVALUATION ............................................ 3
5.1 EROSION HAZARDS ................................................................................................................ 3
5.2 STEEP SLOPE AND LANDSLIDE HAZARDS ............................................................................... 4
5.3 SEISMIC HAZARDS ................................................................................................................. 5
5.4 COAL MINE HAZARDS ............................................................................................................ 6
6.0 GEOTECHNICAL RECOMMENDATIONS ..................................................................... 6
6.1 SITE CLASS FOR SEISMIC DESIGN ........................................................................................... 6
6.2 BUILDING FOUNDATIONS ....................................................................................................... 7
6.2.1 Mat Foundation/Structural Slab with Thickened Edges ................................................ 7
6.2.2 Lateral Resistance .......................................................................................................... 8
7.0 EARTHWORK CONSIDERATIONS .................................................................................. 8
7.1 TEMPORARY EXCAVATIONS ................................................................................................... 8
7.2 MATERIAL REUSE .................................................................................................................. 8
7.3 STRUCTURAL FILL PLACEMENT AND COMPACTION ............................................................... 9
7.4 WET WEATHER EARTHWORK ................................................................................................ 9
7.5 SURFACE DRAINAGE AND EROSION CONSIDERATIONS......................................................... 10
8.0 UNCERTAINTY AND LIMITATIONS ............................................................................ 10
9.0 REFERENCES ...................................................................................................................... 13
Geotechnical Report
Proposed Office and Shop Buildings – 1404 SW Grady Way, Renton Washington
July 12, 2023
PanGEO, Inc. 23-164 1404 SW Grady Way, Renton - GeoRpt.docx ii
List of Figures
Figure 1
Figure 2
List of Appendices
Appendix A
Figure A-1
Figure A-2
Figure A-3
Appendix B
Vicinity Map
Site and Exploration Plan
Summary Test Boring Logs
Terms and Symbols for Boring and Test Pit Logs
Test Boring Log PG-1
Test Boring Log PG-2
Summary Results of Soil Liquefaction Analyses
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GEOTECHNICAL REPORT
PROPOSED OFFICE AND SHOP BUILDING
1404 SOUTHWEST GRADY WAY
RENTON, WASHINGTON
1.0 INTRODUCTION
This report presents the results of our geotechnical study to support the design and construction of
the proposed office and shop building located at 1404 Southwest Grady Way in Renton,
Washington. We completed our engineering study in accordance with our proposal dated May 19,
2023, which was approved by you on May 22, 2023. Our service scope included reviewing
published geologic and geotechnical data in the site vicinity, reviewing conceptual design plans,
conducting a site reconnaissance, drilling two test borings, performing engineering analysis, and
developing the geotechnical design recommendations presented in this report.
2.0 SITE AND PROJECT DESCRIPTION
The project site is an approximately 0.62 acre lot located at 1404 SW Grady Way in Renton,
Washington (see Vicinity Map, Figure 1). The site is roughly trapezoidal in shape, and borders
SW Grady Way to the approximate south, King County Metro Sewer properties to the other three
sides (see Figure 2). The subject site is currently occupied by a small one-story building in the
northeastern portion of the site with surface parking areas. Based on review of the GIS maps, the
existing site grade is generally flat.
We understand that you plan to remove the existing building, and to construct an office and shop
building in the western portion of the site with new asphalt parking in other areas (see Figure 2).
Based on review of the preliminary plans, the proposed office and shop building will be a one-
story high bay structure with slabs on grade. We anticipate that the temporary excavations for the
foundation construction will be on the order of about 3 feet.
The conclusions and recommendations in this report are based on our understanding of the
proposed development, which is in turn based on the project information provided. If the above
project description is incorrect, or the project information changes, we should be consulted to
review the recommendations contained in this study and make modifications, if needed. In any
case PanGEO should be retained to provide a review of the final design to confirm that our
geotechnical recommendations have been correctly interpreted and adequately implemented in the
construction documents.
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3.0 FIELD EXPLORATIONS
Our field exploration consisted of drilling two test boring (PG-1 and PG-2) at the site on June 21,
2023, using a track-mounted drill rig owned and operated by Boretec1, Inc. in Bellevue,
Washington. The approximate boring locations were taped from existing features at the site and
are indicated on the attached Figure 2. The borings were drilled to depths of about 71½ and 21½
feet below the existing grade in PG-1 and PG-2, respectively.
The drill rig was equipped with 8-inch outside diameter hollow stem augers, and soil samples were
obtained from the borings at 2½ and 5-foot depth intervals in general accordance with Standard
Penetration Test (SPT) sampling methods (ASTM test method D-1586) in which the samples are
obtained using a 2-inch outside diameter split-spoon sampler. The sampler was driven into the soil
a distance of 18 inches using a 140-pound weight falling a distance of 30 inches. The number of
blows required for each 6-inch increment of sampler penetration was recorded. The number of
blows required to achieve the last 12 inches of sample penetration is defined as the SPT N-value.
The N-value provides an empirical measure of the relative density of cohesionless soil, or the
relative consistency of fine-grained soils. The completed borings were backfilled with drill cuttings
and bentonite chips.
An engineer from PanGEO was present during the field exploration to observe the drilling, to assist
in sampling, and to describe and document the soil samples obtained from the borings. The
summary boring logs are included in Appendix A, Figure A-2 and A-3. The soil samples were
described using the system outlined in Figure A-1 in Appendix A.
4.0 SITE GEOLOGY AND SUBSURFACE CONDITIONS
4.1 SITE GEOLOGY
Based on review of Geologic Map of the Renton quadrangle, King County, Washington
(Mullineaux, 1965) the project site is underlain by Quaternary Alluvium deposited by the White
and Green Rivers (Geologic Map Unit Qaw). This soil unit generally consists of loose to medium
dense sand and soft to medium stiff silt with occasional organic soil layers.
4.2 SOILS
In summary, our borings generally encountered a layer of fill overlying alluvium consisting of
loose to dense sand, gravelly, and silty sand to the maximum depth of the boring. The following
is a summary of the soil units encountered in our test borings. Please refer to the boring log
included as Figures A-2 and A-3 in Appendix A for more details.
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Fill: Boring PG-1 encountered loose to very dense, gravelly sand and silt that extended to
about 7 feet below the surface. Boring PG-2 encountered very loose to medium dense gravelly
sand that extended to about 7½ feet below the surface. We interpreted this soil unit to be
undocumented fill.
Alluvium (Qal): Below fill, both borings generally encountered layers of loose to medium
dense, silty sand to gravelly sand with occasional organics and shell fragments extending to
the termination depths of the borings at about 70½ and 21½ feet below ground surface in PG-
1 and PG-2, respectively. We interpret this soil unit as mapped alluvium deposit.
Our subsurface descriptions are based on the conditions encountered at the time of our exploration.
Soil conditions between our exploration locations may vary from those encountered. The nature
and extent of variations between our exploratory locations may not become evident until
construction. If variations do appear, PanGEO should be requested to reevaluate the
recommendations in this report and to modify or verify them in writing prior to proceeding with
earthwork and construction.
4.3 GROUNDWATER
Groundwater was observed at about 15 feet below the ground surface in both test borings during
drilling. It should be noted that groundwater elevations and seepage rates are likely to vary
depending on the season, local subsurface conditions, and other factors. Groundwater levels are
normally highest during the winter and early spring.
5.0 GEOLOGICALLY HAZARDOUS AREAS EVALUATION
As part of our study, we conducted an assessment of potential geologic hazards within the subject
site as defined in Renton Municipal Code (RMC) Chapter 4-3-050, Geologically Hazardous Areas.
Chapter 4-3-050 of the RMC identifies four different types of Geologic Hazards: Erosion Hazards,
Steep Slope and Landslide Hazards, Seismic Hazards, and Coal Mine Hazards. A summary of our
assessment of the potential hazard areas with respect to the planned improvements is provided in
the following sections of this report.
5.1 EROSION HAZARDS
According to the City of Renton (COR) GIS map, the site is not mapped as an erosion hazard area.
We reviewed the USDA Natural Resource Conservation Service (NRSC) Soil Survey (NRCS,
2020) for surficial soil information. Review of the soils map for the area of the site available on
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the Web Soil Survey indicates the site is described as Urban Land (Ur). This mapped soil unit is
considered as having a low erosion potential.
Based on the soil conditions encountered in the borings and the site topography, it is our opinion
that the erosion hazard at the site is considered low, and can be effectively mitigated with the best
management practice (BMPs) during construction and with properly designed and implemented
landscaping for permanent erosion control. During construction, the temporary erosion hazard can
also be effectively managed with an appropriate erosion and sediment control plan, including but
not limited to installing a silt fence at the construction perimeter, placing quarry spalls or hay bales
at the disturbed and traffic areas, covering stockpiled soil or cut slopes with plastic sheets,
constructing a temporary drainage pond to control surface runoff and sediment trap, placing rocks
at the construction entrance, etc.
Permanent erosion control measures should be applied to the disturbed areas as soon as feasible.
These measures may include but are not limited to hardscape and landscape. The use of permanent
erosion control mat may also be considered in conjunction with planting/hydroseeding to protect
the soil from erosion.
5.2 STEEP SLOPE AND LANDSLIDE HAZARDS
Based on review of the Renton GIS map, the site is not mapped as a landslide hazard area. As
previously discussed, the site topography is generally flat. We conducted a reconnaissance of the
site on June 5, 2023. Based on our reconnaissance, the site does not contain indications of recent
or historical slope movements, such as scarps, sloughs, tension cracks, uneven ground surfaces,
jackstrawed trees, breaks in vegetation, water features and convergent landforms.
We also reviewed a LiDAR image of the site and its vicinity, and the landslide inventory map from
the Washington Department of Natural Resources (DNR). To the best of our knowledge, there are
no reported past known slides at the site or in the immediate vicinity.
Based on results of the subsurface exploration at the site and our site observations, it is our opinion
that the subject site does not contain landslide hazards. It is our opinion that the proposed
development as currently planned will not decrease the site stability or adversely impact the subject
site and surrounding properties, provided that the proposed project is properly designed and
constructed.
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5.3 SEISMIC HAZARDS
Based on review of the City of Renton GIS maps, the site is mapped as a seismic hazard area.
Liquefaction occurs when saturated predominately sand and silt soils are subjected to cyclic
loading. This causes the porewater pressure to increase in the soil, thereby reducing the inter-
granular stresses. As the inter-granular stresses are reduced, the shearing resistance of the soil
decreases. If pore pressures develop to the point where the effective stresses acting between the
grains become zero, the soil particles will be in suspension and behave like a viscous fluid.
Typically, loose, saturated, and clean granular soils, that have a low enough permeability to
prevent drainage during cyclic loading, have the greatest potential for liquefaction, while more
dense soil deposits with higher silt or clay contents have a lesser potential. Soil liquefaction may
cause the temporary loss/reduction of foundation capacity and ground settlement.
We performed liquefaction analysis based on the deep test boring PG-1 with analysis depth to about
71½ feet, using the GeoLogismiki LiqSvs software suites. The input ground motion parameters in
our analyses included a Magnitude 7.5 earthquake with a Peak Ground Acceleration (PGA) of
0.68g to model an IBC code event. The liquefaction analyses, using the procedure proposed by the
1996 and 1998 NCEER/NSF workshops (Youd et al., 2001) or the methodologies developed by
Boulanger and Idriss (2014), indicate that the alluvial soils below the groundwater table to a depth
of about 60 feet in the project area are potentially liquefiable.
We used the method outlined by Cetin at al. (2009) to estimate the potential post liquefaction
settlement at the proposed foundation level. The Cetin at al. (2009) approach is a probabilistically
based model for the assessment of cyclically induced straining of saturated cohesionless soils. This
approach includes a depth factor that assumes contribution of layers to surface settlement
diminishes as the depth of layer increases, and the settlement of an individual layer that is below
about 18 meters (about 60 feet) deep below the ground surface will not manifest at the ground
surface. Based on the Cetin at al. (2009) approach, we estimate a total post-liquefaction settlement
of about 8 to 8½ inches at the ground surface using computer program GeoLogismiki LiqSvs, and
this estimated settlement using the Cetin at al. (2009) approach is free-field settlement.
In addition to the free-field settlement, we evaluated the potential of shear-induced liquefaction
settlement below the foundation using the approach by Bray and Macedo (2017). Bray and Macedo
(2017) consider that shallow founded buildings could exert shear stresses on the underlying
liquefiable soils and cause settlement due to punching effect or soil-structure-interaction
ratcheting. Based on the Bray and Macedo (2017) approach, we estimated the potential shear-
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induced liquefaction settlement below the foundation to be about 1 inch, in addition to the free-
field settlement.
In summary, based on our settlement calculations referenced above, we anticipate a total
potentially liquefaction-induced foundation settlement of about 8 to 9 inches under the IBC
earthquake event. Assuming the potential differential settlement will be equal to about 50% of
total post-liquefaction settlement, we estimated that the potential differential building settlement
induced by liquefaction will be up to about 4 to 4½ inches. It should be noted that, based on the
uniform soils in our borings, we estimate that the differential settlement for the new foundations
will likely be less than 3 to 4 inches.
To mitigate the potential impacts of the soil liquefaction and ground settlement, we recommend
the proposed new structure be supported by a mat/structural slab placed on 12-inch compacted
structural fill over a layer of geogrid. Based on our discussions with the project structural engineer,
we understand the estimated differential foundation settlement of up to about 3 to 4 inches is
acceptable based on the current structural design.
It should be noted that the estimated foundation settlement under the extreme earthquake event
could potentially result in some architectural and structural damage. However, it is our opinion
that a significant loss of bearing capacity is not anticipated. Additionally, in our opinion, egress
from the new structure should not be severely impacted.
5.4 COAL MINE HAZARDS
According to the City of Renton (COR) GIS map, the site is not mapped as a coal mine hazard
area. Our boring PG-1 drilled to 71½ feet deep did not encounter any coal. Our review of the
available coal mine maps indicated there are no historical coal mines at the site and in the
immediate vicinity. As such, it is our opinion that the site does not contain coal mine hazards.
6.0 GEOTECHNICAL RECOMMENDATIONS
6.1 SITE CLASS FOR SEISMIC DESIGN
We anticipate the seismic design of the structure will be accomplished in accordance with the 2018
International Building Code (IBC). Assuming the fundamental period of vibration for the proposed
structure is less than 0.5 seconds, based on the site soil conditions, it is our opinion that Site Class
E may be assumed for the seismic design of the proposed structure.
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6.2 BUILDING FOUNDATIONS
Based on the subsurface conditions at the site and our understanding of the current design, it is our
opinion that a mat foundation/structural slabs with thickened edges with improved foundation
subgrade is most appropriate foundation system to support the proposed structure to mitigate the
potential impacts of soil liquefaction and estimated differential foundation settlement during a
design earthquake. Our foundation design recommendations are presented in the sections below.
However, if a high level foundation performance is desired, pile foundation may be used to support
the proposed building.
6.2.1 Mat Foundation/Structural Slab with Thickened Edges
The mat foundation/structural slab should be founded on a minimum of 12 inches of structural fill
placed on the recompacted on-site soils. The native subgrade soil should be compacted to a firm
and unyielding condition prior to placement of structural fill. Any soft/loose and pumping native
subgrade soil detected during compaction should be removed and replaced with structural fill. The
structural fill should extend horizontally a minimum of 12 inches beyond the edge of the
foundation. We also recommend that a layer of geogrid reinforcement, such as Tensar BX1100 or
approved equivalent, be placed on the compacted native subgrade, prior to placement of structural
fill to further improve foundation soil stiffness. The geogrid should be overlapped a minimum of
12-inch, where needed.
The mat foundation should be thickened to a minimum depth of 18 inches below the adjacent finish
grade around the perimeter of the mat. The thickened edges of the structural slabs should have a
minimum width of 18 inches.
For design of the mat foundation/structural slab with thickened edges bearing on the prepared
subgrade as discussed above, a modulus of subgrade reaction, ks, of 100 pounds per cubic inch
(pci) may be used. With the mat foundation/structural slab foundation, we anticipate the average
bearing pressure to be less than 1,500 psf.
Provided the mat slab subgrade is prepared as described above, mat foundation/structural slab
settlement is estimated to be approximately one inch with differential settlement on the order of ½
inch during the static loading condition. Based on our analysis, the total settlement for mat
foundation/structural slab due to seismic shaking may be on the order of 8 to 9 inches during an
IBC code-level design earthquake differential settlement should be about 3 to 4 inches or less
across the building footprint.
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6.2.2 Lateral Resistance
Lateral loads acting on the foundations may be resisted by passive earth pressure developed against
the embedded portion of the foundation system and by frictional resistance at the bottom of the
footings. For footings bearing on the compacted structural fill, a frictional coefficient of 0.35 may
be used to evaluate sliding resistance. Passive soil resistance may be calculated using an equivalent
fluid unit weight of 250 pcf, assuming properly re-compacted native sandy soil or compacted
structural fill will be placed against the footings. The above values include a factor of safety of
1.5. Unless covered by pavements or slabs, the passive resistance in the upper 12 inches of soil
should be neglected.
7.0 EARTHWORK CONSIDERATIONS
7.1 TEMPORARY EXCAVATIONS
As currently planned, the proposed construction may require excavations of about 3 feet or less
below the existing grade. We anticipate the excavations to mainly encounter fill underlain by loose
to medium dense sand. All temporary excavations should be performed in accordance with Part N
of WAC (Washington Administrative Code) 296-155. The contractor is responsible for
maintaining safe excavation slopes and/or shoring.
All temporary excavations should be sloped or shored. Based on the soil conditions at the site, for
planning purposes, it is our opinion that temporary excavations for the proposed construction may
be sloped 1H:1V or flatter.
The temporary excavations and cut slopes should be re-evaluated in the field during construction
based on actual observed soil conditions, and may need to be flattered in the wet seasons and
should be covered with plastic sheets. We also recommend that heavy construction equipment,
building materials, excavated soil, and vehicular traffic should not be allowed within a distance
equal to 1/3 the slope height from the top of any excavation.
Based on the subsurface conditions at the site and our understanding of the building design, it is
our opinion that conventional mat foundation/structural slabs with thickened edges are appropriate
to support the new buildings. Our recommendations for designing the foundation system are
discussed in the sections below.
7.2 MATERIAL REUSE
In the context of this report, structural fill is defined as compacted fill placed under footings,
concrete stairs and landings, slabs, or other load-bearing areas. Based on the soil conditions
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encountered in the borings, the onsite soil near the ground surface is poorly graded and is not
suitable to be used as structural fill, but can be used as general fill in the non-structural areas. If
use of the on-site soil is planned, the excavated soil should be stockpiled and protected with plastic
sheeting to prevent softening from rainfall in the wet season.
7.3 STRUCTURAL FILL PLACEMENT AND COMPACTION
Structural fill should consist of imported, well-graded, granular material, such as WSDOT CSBC
or approved equivalent.
Structural fill should be moisture conditioned to within about 3 percent of optimum moisture
content, placed in loose, horizontal lifts less than 8 inches in thickness, and systematically
compacted to a dense and relatively unyielding condition and to at least 95 percent of the maximum
dry density, as determined using test method ASTM D 1557.
Depending on the type of compaction equipment used and depending on the type of fill material,
it may be necessary to decrease the thickness of each lift in order to achieve adequate compaction.
PanGEO can provide additional recommendations regarding structural fill and compaction during
construction.
7.4 WET WEATHER EARTHWORK
In our opinion, the proposed site construction may be accomplished during wet weather (such as
in winter) without adversely affecting the site stability. However, earthwork construction
performed during the drier summer months likely will be more economical. Winter construction
will require the implementation of best management erosion and sedimentation control practices
to reduce the chance of off-site sediment transport. Some of the site soil contains a high percentage
of fines and is moisture sensitive. Any footing subgrade soils that become softened either by
disturbance or rainfall should be removed and replaced with structural fill, Controlled Density Fill
(CDF), or lean-mix concrete. General recommendations relative to earthwork performed in wet
conditions are presented below:
• Site stripping, excavation and subgrade preparation should be followed promptly by the
placement and compaction of clean structural fill or CDF;
• The size and type of construction equipment used may have to be limited to prevent soil
disturbance;
• The ground surface within the construction area should be graded to promote run-off of
surface water and to prevent the ponding of water;
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• Bales of straw and/or geotextile silt fences should be strategically located to control erosion
and the movement of soil;
• Structural fill should consist of less than 5% fines; and
• Excavation slopes should be covered with plastic sheets.
7.5 SURFACE DRAINAGE AND EROSION CONSIDERATIONS
Surface runoff can be controlled during construction by careful grading practices. Typically, this
includes the construction of shallow, upgrade perimeter ditches or low earthen berms in
conjunction with silt fences to collect runoff and prevent water from entering excavations or to
prevent runoff from the construction area from leaving the immediate work site. Temporary
erosion control may require the use of hay bales on the downhill side of the project to prevent
water from leaving the site and potential storm water detention to trap sand and silt before the
water is discharged to a suitable outlet. All collected water should be directed under control to a
positive and permanent discharge system.
Permanent control of surface water should be incorporated in the final grading design. Adequate
surface gradients and drainage systems should be incorporated into the design such that surface
runoff is directed away from structures. Potential problems associated with erosion may also be
reduced by establishing vegetation within disturbed areas immediately following grading
operations.
8.0 UNCERTAINTY AND LIMITATIONS
We have prepared this report for use by 1404 Grady LLC and the project team. Recommendations
contained in this report are based on a site reconnaissance, a subsurface exploration program,
review of pertinent subsurface information, and our understanding of the project. The study was
performed using a mutually agreed-upon scope of work.
Variations in soil conditions may exist between the explorations and the actual conditions
underlying the site. The nature and extent of soil variations may not be evident until construction
occurs. If any soil conditions are encountered at the site that are different from those described in
this report, we should be notified immediately to review the applicability of our recommendations.
Additionally, we should also be notified to review the applicability of our recommendations if
there are any changes in the project scope.
The scope of our work does not include services related to construction safety precautions. Our
recommendations are not intended to direct the contractors’ methods, techniques, sequences or
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procedures, except as specifically described in our report for consideration in design. Additionally,
the scope of our work specifically excludes the assessment of environmental characteristics,
particularly those involving hazardous substances. We are not mold consultants nor are our
recommendations to be interpreted as being preventative of mold development. A mold specialist
should be consulted for all mold-related issues.
This report may be used only by the client and for the purposes stated, within a reasonable time
from its issuance. Land use, site conditions (both off and on-site), or other factors including
advances in our understanding of applied science, may change over time and could materially
affect our findings. Therefore, this report should not be relied upon after 24 months from its
issuance. PanGEO should be notified if the project is delayed by more than 24 months from the
date of this report so that we may review the applicability of our conclusions considering the time
lapse.
It is the client’s responsibility to see that all parties to this project, including the designer,
contractor, subcontractors, etc., are made aware of this report in its entirety. The use of information
contained in this report for bidding purposes should be done at the contractor’s option and risk.
Any party other than the client who wishes to use this report shall notify PanGEO of such intended
use and for permission to copy this report. Based on the intended use of the report, PanGEO may
require that additional work be performed and that an updated report be reissued. Noncompliance
with any of these requirements will release PanGEO from any liability resulting from the use this
report.
Within the limitation of scope, schedule and budget, PanGEO engages in the practice of
geotechnical engineering and endeavors to perform its services in accordance with generally
accepted professional principles and practices at the time the Report or its contents were prepared.
No warranty, express or implied, is made.
We appreciate the opportunity to be of service to you on this project. Please feel free to contact
our office with any questions you have regarding our study, this report, or any geotechnical
engineering related project issues.
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July 12, 2023
23-164 1404 SW Grady Way, Renton - GeoRpt.docx Page 12 PanGEO, Inc.
Sincerely,
7/12/2023 7/12/2023
Lisa A. Dunham, P.E. H. Michael Xue, P.E.
Project Geotechnical Engineer Principal Geotechnical Engineer
ldunham@pangeoinc.com mxue@pangeoinc.com
Geotechnical Report
Proposed Office and Shop Buildings – 1404 SW Grady Way, Renton, Washington
July 12, 2023
23-164 1404 SW Grady Way, Renton - GeoRpt.docx Page 13 PanGEO, Inc.
9.0 REFERENCES
Boulanger, R.W., Idriss, I.M., (2014), CPT and SPT Based Liquefaction Triggering Procedures,
University of California at Davis, Department of Civil & Environmental Engineering.
Boulanger, R.W., Idriss, I.M., (2014), CPT and SPT Based Liquefaction Triggering Procedures,
University of California at Davis, Department of Civil & Environmental Engineering.
Boulanger, R.W., Idriss, I.M., (2014), CPT and SPT Based Liquefaction Triggering Procedures,
University of California at Davis, Department of Civil & Environmental Engineering.
Cetin at al. (2009), Probabilistic Model for the Assessment of Cyclically Induced Reconsolidation
(Volumetric) Settlements, Middle East Technical University, 06531, Ankara, Turkey,
Department of Civil Engineering.
Jonathan D. B., Jorge M., (2017), Simplified procedure for estimating liquefaction-induced
building settlement, University of California, Berkeley, Department of Civil & Environmental
Engineering.
Mullineaux, D.R., 1965, Geologic Map of the Renton quadrangle, King County, Washington,
scale 1:24,00, US. Geologic Survey.
United States Geological Survey (2008), Earthquake Hazards Program, Interpolated
Probabilistic Ground Motion for the Conterminous 48 States by Latitude and Longitude, 2008
Data, accessed via: http://earthquake.usgs.gov/designmaps/us/application.php
WSDOT (2023), Standard Specifications for Road, Bridge and Municipal Construction, M 41-10.
23-164 1
VICINITY MAP
Figure No.Project No.
Not to Scale
Base Map: King County iMap
Proposed Office & Shop Building
1404 SW Grady Way
Renton, Washington
Figure No.Project No.23-164 2
SITE AND EXPLORATION PLAN
Note: Map modified from Sitts & Hill Site Plan Review
Approx. Scale
1" = 20'
Approx. Test Boring Location
Existing Building Footprint
New Building Footprint
Legend:
PG-1
PG-2
Proposed Office & Shop Building
1404 SW Grady Way
Renton, Washington
APPENDIX A
SUMMARY TEST BORING LOGS
MOISTURE CONTENT
2-inch OD Split Spoon, SPT
(140-lb. hammer, 30" drop)
3.25-inch OD Spilt Spoon
(300-lb hammer, 30" drop)
Non-standard penetration
test (see boring log for details)
Thin wall (Shelby) tube
Grab
Rock core
Vane Shear
Dusty, dry to the touch
Damp but no visible water
Visible free water
Terms and Symbols for
Boring and Test Pit Logs
Density
SILT / CLAY
GRAVEL (<5% fines)
GRAVEL (>12% fines)
SAND (<5% fines)
SAND (>12% fines)
Liquid Limit < 50
Liquid Limit > 50
Breaks along defined planes
Fracture planes that are polished or glossy
Angular soil lumps that resist breakdown
Soil that is broken and mixed
Less than one per foot
More than one per foot
Angle between bedding plane and a planenormal to core axis
Very Loose
Loose
Med. Dense
Dense
Very Dense
SPTN-values Approx. Undrained ShearStrength (psf)
<4
4 to 10
10 to 30
30 to 50
>50
<2
2 to 4
4 to 8
8 to 15
15 to 30
>30
SPTN-values
Units of material distinguished by color and/orcomposition from material units above and below
Layers of soil typically 0.05 to 1mm thick, max. 1 cm
Layer of soil that pinches out laterally
Alternating layers of differing soil material
Erratic, discontinuous deposit of limited extent
Soil with uniform color and composition throughout
Approx. RelativeDensity (%)
Gravel
Layered:
Laminated:
Lens:
Interlayered:
Pocket:
Homogeneous:
Highly Organic Soils
#4 to #10 sieve (4.5 to 2.0 mm)
#10 to #40 sieve (2.0 to 0.42 mm)
#40 to #200 sieve (0.42 to 0.074 mm)
0.074 to 0.002 mm
<0.002 mm
UNIFIED SOIL CLASSIFICATION SYSTEM
MAJOR DIVISIONS GROUP DESCRIPTIONS
Notes:
MONITORING WELL
<15
15 - 35
35 - 65
65 - 85
85 - 100
GW
GP
GM
GC
SW
SP
SM
SC
ML
CL
OL
MH
CH
OH
PT
TEST SYMBOLS
50%or more passing #200 sieve
Groundwater Level at time of drilling (ATD)Static Groundwater Level
Cement / Concrete Seal
Bentonite grout / seal
Silica sand backfill
Slotted tip
Slough
<250
250 - 500
500 - 1000
1000 - 2000
2000 - 4000
>4000
RELATIVE DENSITY / CONSISTENCY
Fissured:
Slickensided:
Blocky:
Disrupted:
Scattered:
Numerous:
BCN:
COMPONENT DEFINITIONS
Dry
Moist
Wet
1. Soil exploration logs contain material descriptions based on visual observation and field tests using a systemmodified from the Uniform Soil Classification System (USCS). Where necessary laboratory tests have beenconducted (as noted in the "Other Tests" column), unit descriptions may include a classification. Please refer to thediscussions in the report text for a more complete description of the subsurface conditions.
2. The graphic symbols given above are not inclusive of all symbols that may appear on the borehole logs.Other symbols may be used where field observations indicated mixed soil constituents or dual constituent materials.
COMPONENT SIZE / SIEVE RANGE COMPONENT SIZE / SIEVE RANGE
SYMBOLS
Sample/In Situ test types and intervals
Silt and Clay
Consistency
SAND / GRAVEL
Very Soft
Soft
Med. Stiff
Stiff
Very Stiff
Hard
Phone: 206.262.0370
Bottom of BoringBoulder:
Cobbles:
Gravel
Coarse Gravel:
Fine Gravel:
Sand
Coarse Sand:
Medium Sand:
Fine Sand:
Silt
Clay
> 12 inches
3 to 12 inches
3 to 3/4 inches
3/4 inches to #4 sieve
Figure A-1
Atterberg Limit Test
Compaction Tests
Consolidation
Dry Density
Direct Shear
Fines Content
Grain Size
Permeability
Pocket Penetrometer
R-value
Specific Gravity
Torvane
Triaxial Compression
Unconfined Compression
Sand
50% or more of the coarsefraction passing the #4 sieve.Use dual symbols (eg. SP-SM)for 5% to 12% fines.
for In Situ and Laboratory Testslisted in "Other Tests" column.
50% or more of the coarsefraction retained on the #4sieve. Use dual symbols (eg.GP-GM) for 5% to 12% fines.
DESCRIPTIONS OF SOIL STRUCTURES
Well-graded GRAVEL
Poorly-graded GRAVEL
Silty GRAVEL
Clayey GRAVEL
Well-graded SAND
Poorly-graded SAND
Silty SAND
Clayey SAND
SILT
Lean CLAY
Organic SILT or CLAY
Elastic SILT
Fat CLAY
Organic SILT or CLAY
PEAT
ATT
Comp
Con
DD
DS
%F
GS
Perm
PP
R
SG
TV
TXC
UCC
LOG KEY 13-104_LOGS.GPJ PANGEO.GDT 6/18/13
MODIFIED LAND / FILL - [Hf]
Very dense, brown, silty SAND with gravel, moist.
Very dense, gray, gravelly SAND, moist.
Hard, gray green, SILT with SAND, moist.
Very dense, light gray, gravelly SAND, moist.
Loose, gray, gravelly SAND with SILT, moist.
ALLUVIUM - [Qal]
Loose, gray-green, fine silty SAND to sandy SILT, moist; trace
organics.
--Becomes gray with trace gravel, very moist to wet; layered with traceorganics.
--Becomes wet at 15 feet.
Medium dense, dark gray with multicolored specks, medium to coarse
gravelly SAND, wet; varying amount of fine grave.
--Trace to no gravel.
S-1
S-2
S-3
S-4
S-5
S-6
S-7
56
50/2
50/4
3
32
1
12
2
23
5
55
5
57
Remarks: Standard penetration test (SPT) sampler driven with a 140 lb. safety
hammer. Hammer operated with a rope and cathead mechanism. Coordinates andelevation are approximate and based on their relative location to known site features.This information is provided for relative information only and is not a substitution for
field survey. Datum: WGS84/NAVD88
0.0
2.5
5.0
7.5
10.0
12.5
15.0
17.5
20.0
22.5
25.0
27.5
30.0
The stratification lines represent approximate boundaries. The transition may be gradual.
MATERIAL DESCRIPTION
Figure A-2Other TestsSample No.Completion Depth:
Date Borehole Started:
Date Borehole Completed:
Logged By:
Drilling Company:Depth, (ft)Proposed Office and Shop Building
23-164
1404 Grady Way, Renton
Northing: 47.467642, Easting: -122.236279
71.5ft
6/5/23
6/5/23
L. Dunham
Boretec Inc
Sheet 1 of 3
Project:
Job Number:
Location:
Coordinates:SymbolSample TypeBlows / 6 in.22.0ft
N/A
EC 95 tracked drill rig, hollow stem auger
SPT
Surface Elevation:
Top of Casing Elev.:
Drilling Method:
Sampling Method:
LOG OF TEST BORING PG-1
N-Value
0
Moisture LL
50
PL
RQD Recovery
100
>>
>>
Medium dense, dark gray with multicolored specks, medium to coarsegravelly SAND, wet; varying amount of fine grave. (Continued)
--With thin layers of of silty SAND.
--One inch of wood.
Medium dense, dark gray, silty SAND, wet, trace gravel.
--Heave observed at 40 foot sample; driller adds mud after sampletaken.
--Becomes gravelly.
--Treace Shell fragments.
S-8
S-9
S-10
S-11
S-12
S-13
5
8
10
8
12
9
5
6
5
6
6
9
4
13
19
4
8
15
Remarks: Standard penetration test (SPT) sampler driven with a 140 lb. safety
hammer. Hammer operated with a rope and cathead mechanism. Coordinates andelevation are approximate and based on their relative location to known site features.This information is provided for relative information only and is not a substitution for
field survey. Datum: WGS84/NAVD88
30.0
32.5
35.0
37.5
40.0
42.5
45.0
47.5
50.0
52.5
55.0
57.5
60.0
The stratification lines represent approximate boundaries. The transition may be gradual.
MATERIAL DESCRIPTION
Figure A-2Other TestsSample No.Completion Depth:
Date Borehole Started:
Date Borehole Completed:
Logged By:
Drilling Company:Depth, (ft)Proposed Office and Shop Building
23-164
1404 Grady Way, Renton
Northing: 47.467642, Easting: -122.236279
71.5ft
6/5/23
6/5/23
L. Dunham
Boretec Inc
Sheet 2 of 3
Project:
Job Number:
Location:
Coordinates:SymbolSample TypeBlows / 6 in.22.0ft
N/A
EC 95 tracked drill rig, hollow stem auger
SPT
Surface Elevation:
Top of Casing Elev.:
Drilling Method:
Sampling Method:
LOG OF TEST BORING PG-1
N-Value
0
Moisture LL
50
PL
RQD Recovery
100
Medium dense, dark gray, silty SAND, wet, trace gravel. (Continued)
Boring terminated at about 71.5 feet below grade. Groundwater was
observed at 15 feet below ground surface during drilling.
S-14
S-15
S-16
13
19
20
7
10
9
5
9
10
Remarks: Standard penetration test (SPT) sampler driven with a 140 lb. safety
hammer. Hammer operated with a rope and cathead mechanism. Coordinates andelevation are approximate and based on their relative location to known site features.This information is provided for relative information only and is not a substitution for
field survey. Datum: WGS84/NAVD88
60.0
62.5
65.0
67.5
70.0
72.5
75.0
77.5
80.0
82.5
85.0
87.5
90.0
The stratification lines represent approximate boundaries. The transition may be gradual.
MATERIAL DESCRIPTION
Figure A-2Other TestsSample No.Completion Depth:
Date Borehole Started:
Date Borehole Completed:
Logged By:
Drilling Company:Depth, (ft)Proposed Office and Shop Building
23-164
1404 Grady Way, Renton
Northing: 47.467642, Easting: -122.236279
71.5ft
6/5/23
6/5/23
L. Dunham
Boretec Inc
Sheet 3 of 3
Project:
Job Number:
Location:
Coordinates:SymbolSample TypeBlows / 6 in.22.0ft
N/A
EC 95 tracked drill rig, hollow stem auger
SPT
Surface Elevation:
Top of Casing Elev.:
Drilling Method:
Sampling Method:
LOG OF TEST BORING PG-1
N-Value
0
Moisture LL
50
PL
RQD Recovery
100
MODIFIED LAND / FILL - [Hf]
Medium dense, gray, gravelly SAND with silt, moist.
--Becomes very loose.
ALLUVIUM - [Qal]
Soft, layered gray and dark gray, SILT, moist to very moist.
--Becomes dark brown with fine sand.
Medium dense, dark gray with multicolored specks, medium to coarsegravelly SAND, wet; varying amount of fine gravel.
--Becomes wet.
Boring terminated at about 21.5 feet below grade. Groundwater wasobserved at 15 feet below ground surface during drilling.
S-1
S-2
S-3
S-4
S-5
S-6
5
66
3
11
3
12
1
22
4
56
2
33
Remarks: Standard penetration test (SPT) sampler driven with a 140 lb. safety
hammer. Hammer operated with a rope and cathead mechanism. Coordinates andelevation are approximate and based on their relative location to known site features.This information is provided for relative information only and is not a substitution for
field survey. Datum: WGS84/NAVD88
0.0
2.5
5.0
7.5
10.0
12.5
15.0
17.5
20.0
22.5
25.0
27.5
30.0
The stratification lines represent approximate boundaries. The transition may be gradual.
MATERIAL DESCRIPTION
Figure A-3Other TestsSample No.Completion Depth:
Date Borehole Started:
Date Borehole Completed:
Logged By:
Drilling Company:Depth, (ft)Proposed Office and Shop Building
23-164
1404 Grady Way, Renton
Northing: 47.467518, Easting: -122.236265
21.5ft
6/5/23
6/5/23
L. Dunham
Boretec Inc
Sheet 1 of 1
Project:
Job Number:
Location:
Coordinates:SymbolSample TypeBlows / 6 in.22.0ft
N/A
EC 95 tracked drill rig, hollow stem auger
SPT
Surface Elevation:
Top of Casing Elev.:
Drilling Method:
Sampling Method:
LOG OF TEST BORING PG-2
N-Value
0
Moisture LL
50
PL
RQD Recovery
100
APPENDIX B
SUMMARY RESULTS OF SOIL LIQUEFACTION ANALYSES
SPT BASED LIQ UEFACTION ANALYSIS REPORT
:: Input parameters and analysis properties ::
Analysis method:Fines correction method:
Sampling method:Borehole diameter:Rod length:Hammer energy ratio:
Boulanger & Idriss, 2014Boulanger & Idriss, 2014
Standard Sampler65mm to 115mm3.30 ft1.00
G.W.T. (in-situ):G.W.T. (earthq.):
Earthquake magnitude Mw:Peak ground acceleration:Eq. external load:
Project title : Proposed Office and Shop Building
Location : 1404 SW Grady Way, Renton, WA
SPT Name: PG-1
15.00 ft15.00 ft
7.500.68 g0.00 tsf
Raw SPT Data
SPT Count (blows/ft)40200Depth (ft)100
95
90
85
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
Raw SPT Data
Insitu
CSR - CRR Plot
CSR - CRR 10.80.60.40.20Depth (ft)100
95
90
85
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
CSR - CRR Plot
During earthq.
FS Plot
Factor of Safety 21.510.50Depth (ft)100
95
90
85
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
FS Plot
During earthq.
LPI
Liquefaction potential40200Depth (ft)100
95
90
85
80
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
LPI
During earthq.
CRR 7.50 clean sand curve
Corrected Blow Count N1(60),cs 50454035302520151050Cyclic Stress Ratio*0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
CRR 7.50 clean sand curve
Liquefaction
No Liquefaction
F.S. color scheme
Almost certain it will liquefy
Very likely to liquefy
Liquefaction and no liq. are equally likely
Unlike to liquefy
Almost certain it will not liquefy
LPI color scheme
Very high risk
High risk
Low risk
Project File: Z:\Projects\2023 Projects\23-001 - 23-199\23-164 1404 SW Grady Way, Renton\Engineering Analysis\23-169 Liq Analysis.lsvs
Page: 1LiqSVs 2.0.2.1 - SPT & Vs Liquefaction Assessment Software
This software is registered to: PanGEO, Inc.Raw SPT DataSPT Count (blows/ft)50403020100Depth (ft)1009590858075706560555045403530252015105Raw SPT DataInsituCSR - CRR PlotCSR - CRR10.80.60.40.20Depth (ft)1009590858075706560555045403530252015105CSR - CRR PlotDuring earthq.FS PlotFactor of Safety21.510.50Depth (ft)1009590858075706560555045403530252015105FS PlotDuring earthq.Vertical Liq. SettlementsCuml. Settlement (in)86420Depth (ft)1009590858075706560555045403530252015105Vertical Liq. SettlementsDuring earthq.Lateral Liq. DisplacementsCuml. Displacement (ft)0Depth (ft)1009590858075706560555045403530252015105Lateral Liq. DisplacementsDuring earthq.:: Overall Liquefaction Assessment Analysis Plots ::Project File: Z:\Projects\2023 Projects\23-001 - 23-199\23-164 1404 SW Grady Way, Renton\Engineering Analysis\23-169 Liq Analysis.lsvsPage: 2LiqSVs 2.0.2.1 - SPT & Vs Liquefaction Assessment Software
This software is registered to: PanGEO, Inc.
TestDepth
(ft)
:: Field input data ::
SPT FieldValue
(blows)
FinesContent
(%)
UnitWeight
(pcf)
Infl.Thickness
(ft)
CanLiquefy
2.50 56 12.00 120.00 3.75 No
5.00 100 5.00 120.00 2.50 No
7.50 5 12.00 120.00 2.50 No
10.00 3 12.00 120.00 3.75 Yes
15.00 5 5.00 120.00 5.00 Yes
20.00 10 5.00 120.00 5.00 Yes
25.00 12 5.00 120.00 5.00 Yes
30.00 18 5.00 120.00 5.00 Yes
35.00 21 5.00 120.00 5.00 Yes
40.00 11 5.00 120.00 5.00 Yes
45.00 15 5.00 120.00 5.00 Yes
50.00 32 5.00 120.00 5.00 Yes
55.00 23 5.00 120.00 5.00 Yes
60.00 39 5.00 120.00 5.00 Yes
65.00 19 5.00 120.00 5.00 Yes
70.00 19 5.00 120.00 5.00 Yes
75.00 19 5.00 120.00 5.00 Yes
80.00 19 5.00 120.00 5.00 Yes
85.00 19 5.00 120.00 5.00 Yes
90.00 19 5.00 120.00 5.00 Yes
95.00 19 5.00 120.00 5.00 Yes
100.00 19 5.00 120.00 2.50 Yes
Abbreviations
Depth:
SPT Field Value:Fines Content:
Unit Weight:Infl. Thickness:
Can Liquefy:
Depth at which test was performed (ft)
Number of blows per footFines content at test depth (%)
Unit weight at test depth (pcf)Thickness of the soil layer to be considered in settlements analysis (ft)
User defined switch for excluding/including test depth from the analysis procedure
:: Cyclic Resistance Ratio (CRR) calculation data ::
CRR7.5Depth(ft)SPTField
Value
CN CE CB CR CS (N1)60 (N1)60csFC(%)σv(tsf)uo(tsf)σ'vo(tsf)UnitWeight
(pcf)
Δ(Ν1)60m
2.50 56 1.67 1.00 1.00 0.75 1.00 70 72 4.00012.00120.00 0.15 0.00 0.15 0.26 2.07
5.00 100 1.39 1.00 1.00 0.75 1.00 104 104 4.0005.00120.00 0.30 0.00 0.30 0.26 0.00
7.50 5 1.59 1.00 1.00 0.80 1.00 6 8 4.00012.00120.00 0.45 0.00 0.45 0.55 2.07
10.00 3 1.40 1.00 1.00 0.85 1.00 4 6 4.00012.00120.00 0.60 0.00 0.60 0.59 2.07
15.00 5 1.11 1.00 1.00 0.85 1.00 5 5 0.0865.00120.00 0.90 0.00 0.90 0.62 0.00
20.00 10 1.01 1.00 1.00 0.95 1.00 10 10 0.1185.00120.00 1.20 0.16 1.04 0.55 0.00
25.00 12 0.94 1.00 1.00 0.95 1.00 11 11 0.1255.00120.00 1.50 0.31 1.19 0.53 0.00
30.00 18 0.90 1.00 1.00 1.00 1.00 16 16 0.1655.00120.00 1.80 0.47 1.33 0.48 0.00
35.00 21 0.86 1.00 1.00 1.00 1.00 18 18 0.1845.00120.00 2.10 0.62 1.48 0.46 0.00
40.00 11 0.79 1.00 1.00 1.00 1.00 9 9 0.1115.00120.00 2.40 0.78 1.62 0.56 0.00
45.00 15 0.77 1.00 1.00 1.00 1.00 11 11 0.1255.00120.00 2.70 0.94 1.76 0.52 0.00
50.00 32 0.79 1.00 1.00 1.00 1.00 25 25 0.2905.00120.00 3.00 1.09 1.91 0.40 0.00
55.00 23 0.73 1.00 1.00 1.00 1.00 17 17 0.1745.00120.00 3.30 1.25 2.05 0.47 0.00
60.00 39 0.77 1.00 1.00 1.00 1.00 30 30 0.4855.00120.00 3.60 1.40 2.20 0.36 0.00
65.00 19 0.67 1.00 1.00 1.00 1.00 13 13 0.1405.00120.00 3.90 1.56 2.34 0.51 0.00
Project File: Z:\Projects\2023 Projects\23-001 - 23-199\23-164 1404 SW Grady Way, Renton\Engineering Analysis\23-169 Liq Analysis.lsvs
Page: 3LiqSVs 2.0.2.1 - SPT & Vs Liquefaction Assessment Software
This software is registered to: PanGEO, Inc.
:: Cyclic Resistance Ratio (CRR) calculation data ::
CRR7.5Depth(ft)SPTField
Value
CN CE CB CR CS (N1)60 (N1)60csFC(%)σv(tsf)uo(tsf)σ'vo(tsf)UnitWeight
(pcf)
Δ(Ν1)60m
70.00 19 0.64 1.00 1.00 1.00 1.00 12 12 0.1325.00120.00 4.20 1.72 2.48 0.52 0.00
75.00 19 0.62 1.00 1.00 1.00 1.00 12 12 0.1325.00120.00 4.50 1.87 2.63 0.52 0.00
80.00 19 0.60 1.00 1.00 1.00 1.00 11 11 0.1255.00120.00 4.80 2.03 2.77 0.52 0.00
85.00 19 0.59 1.00 1.00 1.00 1.00 11 11 0.1255.00120.00 5.10 2.18 2.92 0.53 0.00
90.00 19 0.57 1.00 1.00 1.00 1.00 11 11 0.1255.00120.00 5.40 2.34 3.06 0.53 0.00
95.00 19 0.55 1.00 1.00 1.00 1.00 10 10 0.1185.00120.00 5.70 2.50 3.20 0.54 0.00
100.00 19 0.54 1.00 1.00 1.00 1.00 10 10 0.1185.00120.00 6.00 2.65 3.35 0.54 0.00
σv:uo:
σ'vo:m:
CN:CE:
CB:CR:
CS:
N1(60):Δ(Ν1)60N1(60)cs:CRR7.5:
Total stress during SPT test (tsf)Water pore pressure during SPT test (tsf)
Effective overburden pressure during SPT test (tsf)Stress exponent normalization factor
Overburden corretion factorEnergy correction factor
Borehole diameter correction factor
Rod length correction factor
Liner correction factor
Corrected NSPT to a 60% energy ratioEquivalent clean sand adjustment
Corected N1(60) value for fines contentCyclic resistance ratio for M=7.5
Abbreviations
σv,eq(tsf)
rd CSR MSF CSReq,M=7.5 Ksigma CSR*
:: Cyclic Stress Ratio calculation (CSR fully adjusted and normalized) ::
Depth
(ft)
Unit
Weight(pcf)
uo,eq(tsf)
σ'vo,eq(tsf)
FSMSFmax(N1)60csα
2.50 120.00 0.15 0.00 0.15 1.00 0.442 1.00 0.442 1.10 0.402 2.0002.20 721.00
5.00 120.00 0.30 0.00 0.30 1.00 0.440 1.00 0.440 1.10 0.400 2.0002.20 1041.00
7.50 120.00 0.45 0.00 0.45 0.99 0.437 1.00 0.437 1.07 0.407 2.0001.15 81.00
10.00 120.00 0.60 0.00 0.60 0.98 0.434 1.00 0.434 1.04 0.415 2.0001.13 61.00
15.00 120.00 0.90 0.00 0.90 0.97 0.427 1.00 0.427 1.01 0.422 0.2041.12 51.00
20.00 120.00 1.20 0.16 1.04 0.95 0.482 1.00 0.482 1.00 0.481 0.2451.19 101.00
25.00 120.00 1.50 0.31 1.19 0.93 0.518 1.00 0.518 0.99 0.524 0.2391.21 111.00
30.00 120.00 1.80 0.47 1.33 0.91 0.542 1.00 0.542 0.97 0.557 0.2961.35 161.00
35.00 120.00 2.10 0.62 1.48 0.89 0.558 1.00 0.558 0.96 0.581 0.3161.42 181.00
40.00 120.00 2.40 0.78 1.62 0.86 0.566 1.00 0.566 0.96 0.588 0.1891.17 91.00
45.00 120.00 2.70 0.94 1.76 0.84 0.569 1.00 0.569 0.95 0.599 0.2091.21 111.00
50.00 120.00 3.00 1.09 1.91 0.82 0.569 1.00 0.569 0.90 0.629 0.4611.72 251.00
55.00 120.00 3.30 1.25 2.05 0.80 0.566 1.00 0.566 0.92 0.615 0.2831.38 171.00
60.00 120.00 3.60 1.40 2.20 0.77 0.561 1.00 0.561 0.85 0.658 0.7362.00 301.00
65.00 120.00 3.90 1.56 2.34 0.75 0.555 1.00 0.555 0.92 0.604 0.2321.26 131.00
70.00 120.00 4.20 1.72 2.48 0.73 0.547 1.00 0.547 0.92 0.598 0.2221.24 121.00
75.00 120.00 4.50 1.87 2.63 0.71 0.539 1.00 0.539 0.91 0.593 0.2231.24 121.00
80.00 120.00 4.80 2.03 2.77 0.69 0.532 1.00 0.532 0.91 0.586 0.2141.21 111.00
85.00 120.00 5.10 2.18 2.92 0.68 0.524 1.00 0.524 0.90 0.580 0.2161.21 111.00
90.00 120.00 5.40 2.34 3.06 0.66 0.517 1.00 0.517 0.90 0.576 0.2171.21 111.00
95.00 120.00 5.70 2.50 3.20 0.65 0.511 1.00 0.511 0.90 0.569 0.2081.19 101.00
100.00 120.00 6.00 2.65 3.35 0.64 0.505 1.00 0.505 0.89 0.565 0.2091.19 101.00
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This software is registered to: PanGEO, Inc.
σv,eq(tsf)rd CSR MSF CSReq,M=7.5 Ksigma CSR*
:: Cyclic Stress Ratio calculation (CSR fully adjusted and normalized) ::
Depth(ft)UnitWeight
(pcf)
uo,eq(tsf)σ'vo,eq(tsf)FSMSFmax(N1)60csα
σv,eq:
uo,eq:σ'vo,eq:
rd:
α:CSR :
MSF :CSReq,M=7.5:
Ksigma:CSR*:
FS:
Total overburden pressure at test point, during earthquake (tsf)
Water pressure at test point, during earthquake (tsf)
Effective overburden pressure, during earthquake (tsf)
Nonlinear shear mass factor
Improvement factor due to stone columnsCyclic Stress Ratio
Magnitude Scaling FactorCSR adjusted for M=7.5
Effective overburden stress factorCSR fully adjusted (user FS applied)***
Calculated factor of safety against soil liquefaction
Abbreviations
1.00*** User FS:
:: Liquefaction potential according to Iwasaki ::
Depth
(ft)
FS F Thickness
(ft)
wz IL
2.50 2.000 0.00 9.62 0.002.50
5.00 2.000 0.00 9.24 0.002.50
7.50 2.000 0.00 8.86 0.002.50
10.00 2.000 0.00 8.48 0.002.50
15.00 0.204 0.80 7.71 9.355.00
20.00 0.245 0.75 6.95 7.995.00
25.00 0.239 0.76 6.19 7.185.00
30.00 0.296 0.70 5.43 5.835.00
35.00 0.316 0.68 4.67 4.865.00
40.00 0.189 0.81 3.90 4.825.00
45.00 0.209 0.79 3.14 3.795.00
50.00 0.461 0.54 2.38 1.965.00
55.00 0.283 0.72 1.62 1.775.00
60.00 0.736 0.26 0.86 0.345.00
65.00 0.232 0.77 0.09 0.115.00
70.00 0.222 0.00 0.00 0.000.00
75.00 0.223 0.00 0.00 0.000.00
80.00 0.214 0.00 0.00 0.000.00
85.00 0.216 0.00 0.00 0.000.00
90.00 0.217 0.00 0.00 0.000.00
95.00 0.208 0.00 0.00 0.000.00
100.00 0.209 0.00 0.00 0.000.00
48.01
IL = 0.00 - No liquefaction
IL between 0.00 and 5 - Liquefaction not probableIL between 5 and 15 - Liquefaction probable
IL > 15 - Liquefaction certain
Overall potential IL :
:: Vertical settlements estimation for dry sands ::
Depth(ft)(N1)60 τav pGmax(tsf)αbγε15Nc εNc(%)ΔS(in)Δh(ft)εNcwei ght
factor
2.50 70 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.0003.750.00
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This software is registered to: PanGEO, Inc.
:: Vertical settlements estimation for dry sands ::
Depth(ft)(N1)60 τav pGmax(tsf)αbγε15Nc εNc(%)ΔS(in)Δh(ft)εNcwei ght
factor
5.00 104 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.0002.500.00
7.50 6 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.0002.500.00
10.00 4 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.0003.750.83
Abbreviations
τav:
p:Gmax:
α, b:γ:
ε15:Nc:
εNc:Δh:
ΔS:
Average cyclic shear stress
Average stressMaximum shear modulus (tsf)
Shear strain formula variablesAverage shear strain
Volumetric strain after 15 cyclesNumber of cycles
Volumetric strain for number of cycles Nc (%)Thickness of soil layer (in)
Settlement of soil layer (in)
0.000Cumulative settlemetns:
:: Vertical & Lateral displ.acements estimation for saturated sands ::
Depth
(ft)
γlim(%)
ev(%)
dz
(ft)
Sv-1D(in)
(N1)60cs Fα γmax(%)
FSliq LDI
(ft)
evwei ghtfactor
15.00 5 84.97 0.95 0.204 84.97 3.94 5.00 2.366 0.000.75
20.00 10 47.32 0.91 0.245 47.32 2.49 5.00 1.494 0.000.67
25.00 11 42.40 0.89 0.239 42.40 2.06 5.00 1.235 0.000.58
30.00 16 24.69 0.71 0.296 24.69 1.37 5.00 0.823 0.000.50
35.00 18 19.85 0.62 0.316 19.85 1.04 5.00 0.627 0.000.42
40.00 9 52.88 0.93 0.189 52.88 1.32 5.00 0.793 0.000.33
45.00 11 42.40 0.89 0.209 42.40 0.88 5.00 0.529 0.000.25
50.00 25 8.88 0.23 0.461 8.88 0.32 5.00 0.190 0.000.17
55.00 17 22.15 0.67 0.283 22.15 0.22 5.00 0.131 0.000.08
60.00 30 4.65 -0.09 0.736 4.65 0.00 5.00 0.000 0.000.00
65.00 13 34.14 0.83 0.232 34.14 0.00 5.00 0.000 0.000.00
70.00 12 38.03 0.86 0.222 38.03 0.00 5.00 0.000 0.000.00
75.00 12 38.03 0.86 0.223 38.03 0.00 5.00 0.000 0.000.00
80.00 11 42.40 0.89 0.214 42.40 0.00 5.00 0.000 0.000.00
85.00 11 42.40 0.89 0.216 42.40 0.00 5.00 0.000 0.000.00
90.00 11 42.40 0.89 0.217 42.40 0.00 5.00 0.000 0.000.00
95.00 10 47.32 0.91 0.208 47.32 0.00 5.00 0.000 0.000.00
100.00 10 47.32 0.91 0.209 47.32 0.00 2.50 0.000 0.000.00
Abbreviations
8.189Cumulative settlements:
γlim:Fα/N:
γmax:
ev::Sv-1D:
LDI:
Limiting shear strain (%)Maximun shear strain factor
Maximum shear strain (%)
Post liquefaction volumetric strain (%)Estimated vertical settlement (in)
Estimated lateral displacement (ft)
0.00
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References
⦁ Ronald D. Andrus, Hossein Hayati, Nisha P. Mohanan, 2009. Correcting Liquefaction Resistance for Aged Sands Using Measured
to Estimated Velocity Ratio, Journal of Geotechnical and Geoenvironmental Engineering, Vol. 135, No. 6, June 1
⦁ Boulanger, R.W. and Idriss, I. M., 2014. CPT AND SPT BASED LIQUEFACTION TRIGGERING PROCEDURES. DEPARTMENT OF
CIVIL & ENVIRONMENTAL ENGINEERING COLLEGE OF ENGINEERING UNIVERSITY OF CALIFORNIA AT DAVIS
⦁ Dipl.-Ing. Heinz J. Priebe, Vibro Replacement to Prevent Earthquake Induced Liquefaction, Proceedings of the Geotechnique-
Colloquium at Darmstadt, Germany, on March 19th, 1998 (also published in Ground Engineering, September 1998), Technical paper 12-57E
⦁ Robertson, P.K. and Cabal, K.L., 2007, Guide to Cone Penetration Testing for Geotechnical Engineering. Available at no cost at
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Seed, R., and Stokoe, K.H., Liquefaction Resistance of Soils: Summary Report from the 1996 NCEER and 1998 NCEER/NSF Workshop on Evaluation of Liquefaction Resistance of Soils, ASCE, Journal of Geotechnical & Geoenvironmental Engineering,
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⦁ Zhang, G., Robertson. P.K., Brachman, R., 2002, Estimating Liquefaction Induced Ground Settlements from the CPT, Canadian
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⦁ Zhang, G., Robertson. P.K., Brachman, R., 2004, Estimating Liquefaction Induced Lateral Displacements using the SPT and
CPT, ASCE, Journal of Geotechnical & Geoenvironmental Engineering, Vol. 130, No. 8, 861-871
⦁ Pradel, D., 1998, Procedure to Evaluate Earthquake-Induced Settlements in Dry Sandy Soils, ASCE, Journal of Geotechnical &
Geoenvironmental Engineering, Vol. 124, No. 4, 364-368
⦁ R. Kayen, R. E. S. Moss, E. M. Thompson, R. B. Seed, K. O. Cetin, A. Der Kiureghian, Y. Tanaka, K. Tokimatsu, 2013. Shear-
Wave Velocity–Based Probabilistic and Deterministic Assessment of Seismic Soil Liquefaction Potential, Journal of Geotechnical
and Geoenvironmental Engineering, Vol. 139, No. 3, March 1
LiqSVs 2.0.2.1 - SPT & Vs Liquefaction Assessment Software