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  • 1.  ASCE 7-22 12.13.9 Exceptions

    Posted 9 days ago

    "Where the geotechnical investigation report indicates the potential for flow failure or seismically-induced long runout landslides, the provisions of Section 12.13.9 are not applicable and the condition shall be mitigated."      

    What is a reasonable mitigation for a shallow foundation on soils that will have very large (more than tens of feet) lateral spreading and severe liquefaction.   The building is an emergency generator building being built adjacent to an existing pump station built in the 1960's which will also be subjected to the affects of the lateral spreading (we expect it to fail but in the meantime the new building has to be built to meet ASCE 7-22 requirements.

    We are proposing to use a thick mat foundation and a robust masonry shear wall building so that it remains intact during the event.  The building is unocuppied although maintenance staff visits the building monthly for a short duration.



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    Ronald Roberts P.E., S.E., M.ASCE
    Roberts Engineering
    Redmond WA
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  • 2.  RE: ASCE 7-22 12.13.9 Exceptions

    Posted 6 days ago

    With a floating mat, yes, the building will stand a better chance of staying in-tact. But what good is it if it moves tens of feet away? 

    How about piles and pile caps?



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    Jeffrey Walkley P.E., S.E., M.ASCE
    Vice President
    Michael J Walkley, PA
    Towson MD
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    Original Message


  • 3.  RE: ASCE 7-22 12.13.9 Exceptions

    Posted 5 days ago

    We found an answer in ASCE 7-16  12.13.9 and  commentary 12.13.9  

     

    12.13.9 Where the geotechnical investigation report indicates the potential for flow failure, the provisions of Section 12.13.9 are not applicable and the condition shall be mitigated.  (what that mitigation entails is left to our engineering judgement)

     

    Commentary 12.13.9 from ASCE 7-16   "They require mitigation of significant liquefaction-induced risks, either through ground improvement or structural measures, aimed at preventing liquefaction-induced building collapse and permitting the structure and its nonstructural system to satisfy the Section 1.1 performance goals. With the exception of Risk Category IV Essential Facilities, the provisions do not seek to control non-life-threatening damage to buildings that may occur as a result of liquefaction-induced settlement."

     

    Although ASCE 7-22 is not applicable to this project (yet).

     

    12.13.9 Where the geotechnical investigation report indicates the potential for flow failure or seismically-induced long runout landslides, the provisions of Section 12.13.9 are not applicable and the condition shall be mitigated.

     

    Commentary 12.13.9 from ASCE 7-22     "They require mitigation of significant slope instability, liquefaction, settlement, fault, and lateral spreading risks, through either ground improvement or structural measures, aimed at preventing building collapse and permitting the structure and its nonstructural system to satisfy the Section 1.1 performance goals.  (apparently under 7-16 we only have to prevent liquefaction-induced building collapse, in 7-22 we also have to prevent lateral spreading induced building collapse)

     

    The pump station is existing, and we aren't touching it, we're building a new emergency generator building nearby on the same site.  No matter what we do to protect the emergency generator building, the pump station, (and much of the surrounding neighborhood) will experience significant lateral flow into the Duwamish River, it's not realistic to think we can prevent the large area of lateral spreading that the Geotechs predict.  

     

    We've decided to go with the mat foundation and a "robust" reinforced CMU wall building to prevent life threating building collapse.

     

     

     

    Ronald M. Roberts, PE, SE Washington and Oregon

    Roberts Engineering PLLC

    17503 NE 137th Street

    Redmond, WA  98052-2182

    (425)556-0300

     




    Original Message


  • 4.  RE: ASCE 7-22 12.13.9 Exceptions

    Posted 4 days ago

    Have three patents in new technology in the area of electrical generation . Cost might be controlled using a lighter gas turbine associated electrical generation system .



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    Attending ( www.ascemetsection.org ) ASCE civil engineers event . 22nd Annual William Barclay Parsons Lecture , Thursday, May 02, 2024 , 05:30pm - 07:00pm ASME Turbo Expo London - Preliminary plan arrive London 20 June ( Thursday ) leave Saturday June 29th . Hope to meet you . Back Grounder - Len Andersen 914-536-7101 -- 50% lowering cost of electricity granted mostly reducing distribution losses ! 94% Fuel to Electricity efficiency heard on 3 patents tech ! Joy to the world my plus 10 % fuel efficiency aircraft , train automotive Patent attorney's Leason Ellis LLP www.leasonellis.com 1 Barker Ave, White Plains, NY 10601 (914) 288-0022 ---- Sincerely Leonard M. Andersen Engineer Inventor of 11 patents so far AWS CWI ( Certified Welding Inspector ) len@... // len@... // len.turbine@... // POB 1529 New York, New York 10116 ( +1650 per year Caller Box ) at Penn Station NYC . PICKUP Wednesdays and hear "We steal your mail." 20 times and one first class piece from the government of the city of New York . 914-536-7101 Cell Phone / 914-237- 7689 Home / 800-428-4801 . ---- www.lenandersen.com - ( site to suppress impersonation ) --- www.gasturbineandersen.com . Told of on 100 kw units with my technology gave 94 % fuel efficiency . About a 2 ton unit that can be positioned to greatly reduce the normal 50 % distribution losses at 90 % efficiency heard of . Have tech 3 patents greatly reduces electrical cost and cost of aircraft propulsion . At Office Home Residence 46 Alexander Av Yonkers NY 10704 - 5 PM to 5 AM 7 days - Propaganda ! Heard Turbo Expo London 26 - 28 June - GE + Pratt Whitney + MIT Gas Turbine Lab have interest ! My answer ! Standing by . Reply to fellow engineers with nice words - Bless you ! Bless you ! Bless you ! " Office residence 46 Alexander Av / Yonkers / NY 107044227 . How might I , Len Andersen ASME Turbo Expo do you good ? Been to London Many times . Knowledgeable about hotel and public transportation – restau
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    Original Message


  • 5.  RE: ASCE 7-22 12.13.9 Exceptions

    Posted 3 days ago

    After the Pedernales' earthquake (April 16 of 2016) in Northern coast of Ecuador(7.8 Magnitude) we have to design a R/C building in the affected area.

    For the foundation we used circular shaped R/C piles,  and casted in situ. By the way the Building was located a 100 m from the seashore. so we have to consider periodic water level variations. The soil was prone to liquefaction. So far, since 2016, we had a couple of tremors but no problem with the building at all.

    So I suggest you to use piles in your structural design. 

    Carlos Jaramillo 

    PRESIDENT

    JAIC Cia. Ltda.

    Ibarra - Ecuador



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    Carlos Jaramillo Aff.M.ASCE
    JAIC
    Ibarra
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    Original Message


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