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HomeMy WebLinkAboutItem 8 PPP 05-06-2020 Operations Committee - Seismic Eval Project Seismic Evaluation y of Structures at Plant MIAy. l Nos . 1 and 2 Project PS15-06 - r = Kathy Millea, Director of Engineering Operations Committee May 6, 2020 MacW Foster i ng esie n ce y at OCSD SEISMIC EVALUATION OF STRUCTURES Orange County AT PLANTS 1 AND 2 « • « Sanitation District I.P.a IUaT.1 Climate Resiliency Study Collections Capacity Evaluation Study Execu' aryl "-t /�.��►ya•�� PROJECT NO.PSIS-08 lr If TUNE u.zms - - m 4 ., 2019 ASSET F i' MANAGEMENT 9 • . PLAN orange counry S—canon D;srnc[caino— • iRM • �Long History of .- S E I t eismic va ua ions r j. 1 � 1 Seismic Risk SP-182: Plant No. 2 PS15-06: Seismic Analysis Plants 1 Digesters and Evaluation of and 2 Tunnels Seismic Structures at Plant Evaluated process Hazard Evaluation Nos. 1 and 2 facilities at Plant Quantify the Evaluated process Nos. 1 and 2 vulnerability of facilities at Plant relative to their Plant No. 2 Nos. 1 and 2 performance to digesters and constructed prior to 1991 Building Code associated facilities 2001 Building Code T�T- Long Seismic IT'M-Id7t%" Evaluations '. .... qjjjljjjjj!!!jjjjjjjjjjjjjjjjj Seismic Risk SP-182: Plant No. 2 PS15-06: Seismic Analysis Plants 1 Digesters and Evaluation of and 2 Tunnels Seismic Structures at Plant Evaluated process Hazard Evaluation Nos. 1 and 2 facilities at Plant Quantify the Evaluated process Nos. 1 and 2 vulnerability of facilities at Plant relative to their Plant No. 2 Nos. 1 and 2 performance to digesters and constructed prior to 1991 Building Code associated facilities 2001 Building Code 1SMIC Risks Local Faults Liquefaction Lateral Spread \Orwa .nt AeHflowQ �,--ue U11t en .Palma ; - •r - f�' �+ Hawiian Gardens tt J ress Stantoe s Anaheim os 4 Lon r - r° a'..� Pt``♦�' m��r Santa Ana ��,�� o'•��i`'v ;• ': Fountain +JO*yy�:��� 4-�I Valley _ 00 .w t ,vi t f�y of♦ *j 00 0 �� :v � -� Impact Seismic Hazards ti ah qSeveral Local Faults 1 LEGEND e�y hdre MAPPED FAULT TRACES aS IuwrCRMOALL,19M) \ �/� •�- ,,� — — HIGH ACTIVITY LEVEL �O LOW TO MODERATE �000, LEVEL \ ���� � ����• ACTIVITY LOW ACTIVITY LEVEL � `.',.� _ '•t :G'-� .�. + i JUNE 2017 DRAFT p. P2-98/J-117 FAULT \ ` ) t �% �� �•� !mod ZONES 1 r � ✓, ~ s` Sao \n i ' DAFTs A,B,C,D ♦y, BIOFILTERS] :v Potential Liquefaction mm"m.TI Hazard Zone .... ............ ............. .............. ...... ............... ....I....... r vp .............. ........... ..... .................. ... . ..... ... . ...... t ................ ti .......... . ........ :j: — .. :F"u:n:taiii: �all:e' {{ s • E1: ...: L' ♦ ♦ ♦ . ♦ ♦ ♦ r Plai - . •••�' • Y �. ♦ �+ t. E �f ♦ ,� ` ♦ ♦ •00 ♦ 00 ♦0 `0 y Hunts #bn::Beachi 9. _ Plant 2 Santa Ana eights :: ill Ch ` : . :s a Mesa ' N J A v1N i r s Y Source: EPA Li uefaction Hazard Ma q p .. Lateral Spread a Risk LATERAL SPREAD Before earthquake: Liquefiable sediment After earthquake: 1� Lateral Sa Risk i►1' 1�- IC. zx ,. %I�K.-0�2 k 1 ` Mitigation Measures If this is the problem . . . Local Faults Liquefaction Lateral Spread ru a Anaheim OrJnt �'.. Lnn Sanla Ana �"�� ��jr��� .�•�o:�t j � � ,00 �, Structural Mitmigation , 4 1 Vulnerability Mitigation Separation of the roof element from Installation of wall anchorage the wall caused roof to collapse 4W - - Ex*wV W33X or W 12X Roof Beam t Add Through-Bons _ to Connect Angie I to WaIL'Pdaster Stdfener-I Ref: 1994 Northridge Earthquake. EERI, Earthquake Stiffenerie with Engineering Research Institute RetrofiWeldedt olEx�istng Steel Beam Existing Concrete PRlaster %I�K.-0�2 k . eotechn 'ical Mit 'igation Vulnerability Mitigation Soils became liquified during a Deep soil mixing is one alternative seismic event, reducing the to stabilize soil by "cementing" ground's ability to support the sand particles together loads 1 ''�'���.�� fit:�. • _ - �,F, �0 %A$ 07 40 00 Niigata Japan,June 16, 1964 Photo Credit: National Geophysical Data Center a Lateral Spread � 1 iga M t Iionr► '+� Aid I Vulnerability Mitigation Seismic event causes soil to Installation of closely spaced piles move laterally towards a free effectively creates a "wall" that is surface of lower elevation designed to resist lateral soil (river bed) movement � M • __ _ .� Y.I. kwt It f Ref: Michael J. Crozier, 'Landslides- Hill country, regolith and submarine landslides',Te Ara -the Encyclopedia of New Zealand � " Summary of Seismic 4 R Is I qa ion kMti t 63 Structures Evaluated 1110, Designed to older Building Codes that do not consider current seismic performance criteria 48 Structures Identified with Structural Structural $25 M $16 M and/or Geotechnical Deficiencies Geotechnical $11 M $143 M Deficiencies from design code changes that influence Lateral Spread $100 M $50 M loading conditions and building performance during seismic events 16 Structures Impacted by Lateral Spread Caused by liquefiable soils and vertical separation between the plant sites and the Santa Ana River or Talbert Marsh 13 Structures Improved Under Planned Projects Identified in the 2017 Facilities Master Plan; separate seismic projects will be created for other facilities 3 Structures Require Complete Replacement The seismic upgrade costs are greater than the value of the structure / I / %I�K-.-0�2 k Recommendations Study Summary BudgetProposal Mitigation Plant 1 Plant 2 MitigationPlant 1 Plant 2 costs Costs Structural $25 M $16 M Structural $25 M $16 M Geotechnical $11 M $143 M Geotechnical $9 M $125 M Lateral Spread $100 M $50 M Lateral Spread $100 M $50 M A Strategic Seismic Program ;.. .! 4 ` L MM M, 9 l g T Will Reduce Lon , erm Risk Risks Replacement costs of critical facilities that may be compromised from a seismic i event � Risk 0 Seismic Program Implementation Mitigation Cost costs of performing seismic Time rehabilitation of facilities ■ � q T WV lopy ;� r -is