Topic Thread

  • 1.  Wind Loads for Elevated Beach House

    Posted 11-02-2022 02:55 PM

    A friend who is designing an elevated beach house asked me a question about the wind load underneath the house. He could not find provisions in ASCE 7. Should he consider wind load under the house? If no, why not?  If yes, how?

     

    Thanks! 

     

     


    #WindandWindLoads

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    Huajie (Leo) Liu, PhD.,S.E., P.E., M.ASCE
    Engineering Manager
    LCRA
    Austin TX
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  • 2.  RE: Wind Loads for Elevated Beach House

    Posted 11-03-2022 10:34 AM
    Please refer to the new ASCE 7-22, it appears there has been some criteria added for elevated buildings.

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    William Rosencutter P.E., M.ASCE
    Engr
    Meca Enterprises Inc
    Broken Arrow OK
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  • 3.  RE: Wind Loads for Elevated Beach House

    Posted 11-03-2022 10:37 AM

    There will of course be wind pressure (both suction and compression) on the first floor level.  The reality is, however, that this is never likely to control the design.  I doubt that designers of these buildings consider it (but don't know).  The live load design for the floor (40 psf), factored by 1.6 will greatly exceed any factored wind load suction pressure.  It would be difficult to get significant wind pressure pusing upward, but it would be a good idea to block the floor joists so that in the unlikely event this happens, the joists don't laterally torsionally buckle.

    If the engineer wants to prove all this to himself, he could treat the floor as a "roof" and apply the associated pressure coefficients from ASCE 7



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    Ronald Hamburger P.E., F.SEI
    Principal
    Simpson Gumpertz & Heger
    Oakland CA
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  • 4.  RE: Wind Loads for Elevated Beach House

    Posted 11-03-2022 03:05 PM
    Hi Huajie,
    Have you considered section 29.4.2.3?  I recognize that a house is typically not a circular tank but perhaps you'd find some useful guidance.  The notion of interpolation based on the clearance is probably something you can adapt/apply.  There's also a 'bread crumb' in the commentary as to where you might find more (Australian reference), possibly even for non-circular objects(?).  I haven't' looked through 22 yet so naturally if there's something more suited there then you'd want to use that instead.

    I agree with Ron that it may have been often excluded and probably won't govern, except possibly with regard to overturning so I'd think it's worth a check.

    Hope this helps,
    Keith

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    Keith MacBain Ph.D., P.E., M.ASCE
    Associate & Chief Analyst
    Geiger Engineers, Campus 2
    Suffern NY
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