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    Active Member
    heetap
    Posts: 7
    Registered: ‎02-28-2012
    Accepted Solution

    Load Definition - kN/m2?

    459 Views, 14 Replies
    02-28-2012 01:52 PM

    Hello,

     

    Is there any way I can apply a udl in kN/m2? As I have characteristic design loads with those units and I am finding it difficult to find any load definition that will allow me to apply it; the uniform load is obviously in kN/m. This is for a curved roof structure, modelled as a series of straight I-beams. It's all quite simple for now, but frustrating...

     

    Thanks.

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    Active Member
    heetap
    Posts: 7
    Registered: ‎02-28-2012

    Re: Load Definition - kN/m2?

    02-28-2012 04:49 PM in reply to: heetap

    Ok, so I've tried a cladding and applied a uniform planar load, and it seems to be...ok. However, I don't seem to be getting any results (e.g. deflections, shear, etc.) from the snow load case, even though it has the highest magnitude. Doesn't sound reasonable... I would have thought there would be at least some sort of result.

     

    Cheers.

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    Product Support
    Artur.Kosakowski
    Posts: 2,769
    Registered: ‎12-17-2010

    Re: Load Definition - kN/m2?

    02-29-2012 12:04 AM in reply to: heetap

    Please check if you have the same settings as discussed in http://forums.autodesk.com/t5/Autodesk-Robot-Structural/Claddings-and-geometrical-objects/m-p/306900...

     

    If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.



    Artur Kosakowski
    Support Specialist
    Product Support
    Autodesk, Inc.

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    Active Member
    heetap
    Posts: 7
    Registered: ‎02-28-2012

    Re: Load Definition - kN/m2?

    02-29-2012 02:12 AM in reply to: heetap

    Thanks, I have tried that. Doesn't seem to work.

    I have just tried remodelling, and I've realised when I apply dead, wind or snow load in any direction to the 'top' claddings the loads are displayed but they produce no results. Only the self-weight of the structure produces reactions on those claddings. Wind load applied to the side claddings (columns) produces results fine though.

    Is there some kind of cladding-to-beam connection I seem to be missing here? If there is such a thing?

    Sorry, I'm still at the intermediate stages of learning with Robot. Thanks for all your help.

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    Product Support
    Artur.Kosakowski
    Posts: 2,769
    Registered: ‎12-17-2010

    Re: Load Definition - kN/m2?

    02-29-2012 02:30 AM in reply to: heetap

    When a cladding is defined at the same level as its supporting beams are then any surface load applied to this cladding should be transferred to the beams. From your description I would say that the beams and the claddings have to be defined at slightly different levels. If this is the case you can try to correct this situation in the way described here (adjust to plane):

     

    http://forums.autodesk.com/t5/Autodesk-Robot-Structural/Detailed-Correction/m-p/3079956/highlight/tr...

     

    If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

     

     



    Artur Kosakowski
    Support Specialist
    Product Support
    Autodesk, Inc.

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    Active Member
    heetap
    Posts: 7
    Registered: ‎02-28-2012

    Re: Load Definition - kN/m2?

    03-01-2012 07:21 AM in reply to: Artur.Kosakowski

    I've basically added claddings to the same nodes that the beams are defined. I'm still having the same problem. Is there any other way I can add a distributed load to these beams?

    Thanks.

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    Product Support
    Artur.Kosakowski
    Posts: 2,769
    Registered: ‎12-17-2010

    Re: Load Definition - kN/m2?

    03-01-2012 07:59 AM in reply to: heetap

    Could you make a screen capture that shows the part of the structure with the cladding that makes troubles  (or even better send the model) please?



    Artur Kosakowski
    Support Specialist
    Product Support
    Autodesk, Inc.

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    Distinguished Contributor
    AlexDT
    Posts: 139
    Registered: ‎06-14-2011

    Re: Load Definition - kN/m2?

    03-01-2012 08:06 AM in reply to: Artur.Kosakowski

    Could it have anything to do with the "Model > Trapezoidal and triangular method = Analyze/Ignore?" in the Inspector Dialog Box?

    I thought that if an element has this parameter on ignore, it wont be seen by claddings.

     

    Right?

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    Product Support
    Artur.Kosakowski
    Posts: 2,769
    Registered: ‎12-17-2010

    Re: Load Definition - kN/m2?

    03-01-2012 08:07 AM in reply to: AlexDT

    Correct.



    Artur Kosakowski
    Support Specialist
    Product Support
    Autodesk, Inc.

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    Active Member
    heetap
    Posts: 7
    Registered: ‎02-28-2012

    Re: Load Definition - kN/m2?

    03-01-2012 08:40 AM in reply to: Artur.Kosakowski

    It's the whole model that's affected. I tried attaching the model, but .rtd files aren't allowed...?

    So attached are some screenshots. COMBI is dead, snow and wind. The displacement results for the wind is due to the x-direction loading only, hence, z-direction wind load does nothing. Loading in z-direction does not produce results for any load case, as evidenced by the snow load screenshot. Thanks very much.

     

    Edit: Alex - thanks for your input. However, all beams are under 'analyse'.

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