EXH1218049659

Analysis of Areas with Potential Foundation Instability 3 Recommended Subgrade Improvements 4 Other Construction Recommendations 5 Work in Progress 5 Organization of This Report 5 GEOTECHNICAL OVERVIEW OF SUBSURFACE CONDITIONS 6 Areas Addressed in this Report 6 Existing Information 6 Subgrade Improvement Needed for Specific Soil Conditions to Provide Stability 7 Occurrence of Problematic Subgrade Conditions Impacting Slope Stability 7 GEOTECHNICAL RECOMMENDATIONS FOR CONSTRUCTION 12 Embankment Site Preparation 12 Subgrade Improvement 15 Embankment Underdrain 16 Embankment Fill 17 Slope Face Treatment 17 USE OF THIS REPORT 18 REFERENCES 20 TABLES SoilGradationsfor EmbankmentFillMaterialGroups 22 Water Level Data 23 Hart Crowser -sDa'e iJ-4978-28 AR 049660 CONTENTS (Continued) PaRe FIGURES VicinityMap SiteandExplorationPlan,EmbankmentSlopeBetweenNSA and West MSEWalls SiteandExplorationPlan,EmbankmentSlopeBetweenWest and SouthMSEWalls Siteand ExplorationPlan,Phase4 Fill RecommendedPhase4 SubgradeImprovementArea APPENDIX A SLOPE STABILITY AND DEFORMATION ANALYSES A-1 Introduction A-1 Limit Equilibrium Slope Stability Analyses A-1 Additional Special Explorations A-6 Statistical Analysis of Liquefaction A-6 Deformation Analysis for Discontinuous Liquefaction Conditions A-9 FIGURE A-1 Illustrationof ProbabilisticBasedLiquefaction9% Probabilityof Liquefaction TABLES A-1 LimitEquilibriumAnalyses A-1 A-2 Summaryof Input Soil Parameters A-4 A-3 GeneralizedSummaryof LimitEquilibriumResults A-5 A-4 Resultsof LiquefactionAnalysisfor DifferentEarthquakeEvents A-7 A-5 SoilPropertiesUsedin the Displacement-Based(FLAC)Model at Station 193+19 A-IO A-6 DisplacementsCalculatedfor the 175-YearSeismicEvent(9% liquefaction) A-11 A-7 DisplacementsCalculatedfor the 475-YearSeismicEvent (33% liquefaction) A.11 A-8 DisplacementsCalculatedUsingthe CompositeStrengthMethod A-12 A-9 DisplacementsCalculatedUsingthe ProbabilisticStrengthMethod A-13 Hart Crowser rt_Oa-e iiJ-4978-28 AR 049661 CONTENTS (Continued) Paee APPENDIX B STABILITY ANALYSES CROSS SECTIONS FIGURES B-1 2H:IV EmbankmentSectionUsedfor StabilityAnalyses,Section 170+23 B-2 2H:1V EmbankmentSectionUsed for StabilityAnalyses,Section187+60 B-3 2H:IV EmbankmentSectionUsedfor StabilityAnalyses,Section193+19 13-4 2H:IV EmbankmentSectionUsedfor StabilityAnalyses,Section206+44 B-5 2H:1V EmbankmentSectionUsedfor StabilityAnalyses,Section210+00 B-6 2H:1V EmbankmentSectionUsedfor StabilityAnalyses,Section212+50 APPENDIX C…

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PSCAA Advisory Council Meeting Agenda
Add to CalendarMWednesday Mar 11, 9:00am - 11:35am
1904 3rd Avenue, Suite 105, Seattle, WA 98101
Call to order – Roll Call – Quorum Established – Land Acknowledgement We would like to acknowledge that our Agency operates in four present-day counties, which are the traditional lands of the Coast Salish people, past and present. This acknowledgement does not take the place of authentic relationships with indigenous communities in our jurisdiction and [...]