Inclusion of Self Weight for analysis

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Araj
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Inclusion of Self Weight for analysis

Post by Araj » Wed Dec 15, 2004 12:36 am

Hello !!!

How can I include the self weight of the element member for analysis in OpenSees ?

Is there any specific command for that ?

Thank you

With regards,
Aloke

fmk
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Post by fmk » Wed Dec 22, 2004 7:36 pm

it depends on the elements you are using .. at the moment some do and some don't .. what are you using?

Araj
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Post by Araj » Sun Jan 02, 2005 8:55 pm

I am using the "element nonlinearBeamColumn " and "element beamWithHinges" for the analysis.

fmk
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Post by fmk » Tue Jan 04, 2005 10:15 am

these elements do not have a self-weight option .. to provide self-weight for these elements you can apply some uniform beam loads.

kadirtopcu
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Re: Inclusion of Self Weight for analysis

Post by kadirtopcu » Tue Nov 19, 2013 1:20 pm

and how about the truss element and displacement beam column element?

fmk
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Re: Inclusion of Self Weight for analysis

Post by fmk » Wed Nov 20, 2013 8:46 am

nope. basically the continuum elements do, the line elements do not.

hshoar
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Re: Inclusion of Self Weight for analysis

Post by hshoar » Sun Jan 05, 2014 1:41 am

Dear fmk,
Could we use uniform beam loads to impose weight for vertical elements, like columns? or brace elements?
Thanks.

kadirtopcu
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Re: Inclusion of Self Weight for analysis

Post by kadirtopcu » Thu Jan 09, 2014 5:22 am

Dear hshoar,
İf you find any answer for your question, could you please write here ? Because I am also confused about it.

fmk
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Re: Inclusion of Self Weight for analysis

Post by fmk » Thu Jan 09, 2014 9:49 am

yes. of course!

kadirtopcu
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Re: Inclusion of Self Weight for analysis

Post by kadirtopcu » Sun Mar 09, 2014 5:09 am

Dear fmk
When we apply uniform loads to braces, which direction sould we use ? because in local axes, it is not including downwards direction.

lorcancon
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Re: Inclusion of Self Weight for analysis

Post by lorcancon » Wed Jul 09, 2014 3:55 am

Hi all,

When working with a larger model, It may be useful to create a loop which will automatically apply self weight as a line load for all elements. Something like the following:

foreach elem [getEleTags] {
set area [lindex [eleResponse $elem section] 4]; # Here we need to get the area of element with tag "$elem"
set unitW 7.85; #For example
set Wz [expr $area*9.81*unitW]
pattern Plain 1 Linear{
eleLoad $elem -type -beamUniform $Wz
}
}

However, the "eleResponse" command only gives information about responses to loads. We require a command here which gives a list of element properties (e.g. stiffness, inertia, Area etc). Frank, maybe such a command already exists?

Regards,
Lorcan

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