uniaxialMaterial Bilin

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afakhimi
Posts: 26
Joined: Sun Nov 27, 2011 6:35 am
Location: Isfahan University Of Technology

uniaxialMaterial Bilin

Post by afakhimi »

hi
i Read a paper posted under reference 8 on the wiki page of Bilin material to understand the parameters of uniaxialMaterial Bilin. but i dont understand some of parameters because they are not define in that Ref.
please help me so that i know them more.
thanks a lot
afakhimi
Posts: 26
Joined: Sun Nov 27, 2011 6:35 am
Location: Isfahan University Of Technology

Re: uniaxialMaterial Bilin

Post by afakhimi »

can anyone help me?
Last edited by afakhimi on Sat May 05, 2012 7:54 pm, edited 1 time in total.
vesna
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Location: UC Berkeley

Re: uniaxialMaterial Bilin

Post by vesna »

What material parameters are not defined in the reference paper?
afakhimi
Posts: 26
Joined: Sun Nov 27, 2011 6:35 am
Location: Isfahan University Of Technology

Re: uniaxialMaterial Bilin

Post by afakhimi »

what are $Lamda_S $Lamda_C $Lamda_A $Lamda?
lowercase or uppercase for landa?
afakhimi
Posts: 26
Joined: Sun Nov 27, 2011 6:35 am
Location: Isfahan University Of Technology

Re: uniaxialMaterial Bilin

Post by afakhimi »

for theta_p parameter , L/d is needed. L=shear span
shear span for a plain frame what means?
vesna
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Location: UC Berkeley

Re: uniaxialMaterial Bilin

Post by vesna »

L is distance from plastic hinge location to point of inflection
sirvan
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Location: razi

Re: uniaxialMaterial Bilin

Post by sirvan »

dear vesna
I m going to use bilin material to model strength deterioration in order to study post yield bahaviour of CBF braces.
regarding to afakhimi's post I also need to know what $Lamda_S $Lamda_C $Lamda_A $Lamda are?are they "reference cumulative plastic rotation" or...........?
thanks in advance
Last edited by sirvan on Wed Jul 11, 2012 3:07 am, edited 1 time in total.
vesna
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Location: UC Berkeley

Re: uniaxialMaterial Bilin

Post by vesna »

I believe it is explained in one of the papers referenced at the bottom of the page for Bilin material.
sirvan
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Location: razi

Re: uniaxialMaterial Bilin

Post by sirvan »

Dear Vesna
thanks for your helpful answer
I also need to consider strength and stiffness deterioration in CBF' braces' inelastic behavior. In your point of view what is the proper way to do so?
thanks in advance.
vesna
Posts: 3033
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Location: UC Berkeley

Re: uniaxialMaterial Bilin

Post by vesna »

sirvan
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Location: razi

Re: uniaxialMaterial Bilin

Post by sirvan »

Dear Vesna
I have already read that report.I need to clarify that by means of stiffness and strength significant deterioration I intend to model progressive failure of braces without removing them from the model during analysis, as it is complicated procedure. considering that I need a proper steel material which I have not found yet. Do you have any suggestion?
thanks in advance
vesna
Posts: 3033
Joined: Tue May 23, 2006 11:23 am
Location: UC Berkeley

Re: uniaxialMaterial Bilin

Post by vesna »

If you read that report carefully you will see that the authors develop fatigue material to predict the failure of the brace. By wrapping fatigue material around Steel02 they were able to predict brace failure successfully.
sirvan
Posts: 14
Joined: Mon Jul 09, 2012 4:15 am
Location: razi

Re: uniaxialMaterial Bilin

Post by sirvan »

dear vesna
what are appropriate values for $Lamda_S $Lamda_C $Lamda_A $Lamda in uniaxialmaterial bilin for modelling steel material?
thanks in advance
vesna
Posts: 3033
Joined: Tue May 23, 2006 11:23 am
Location: UC Berkeley

Re: uniaxialMaterial Bilin

Post by vesna »

Bilin material is a contributed material. Look at references of Bilin for meaning of lambda parameters.
sirvan
Posts: 14
Joined: Mon Jul 09, 2012 4:15 am
Location: razi

Re: uniaxialMaterial Bilin

Post by sirvan »

dear vesna
there are 2 Lambda in the reference....LAMBDA=Theta-p*lambda....Which one does it mean?...as respect to the reference i got 1.84 for LABDA and 0.08 for Thta-p --------->lambda=1.84/0.08=23....which one should i use in bilin material?
thanks in advance
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