Zero length elements with shear-axial interaction

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giovannimilan
Posts: 71
Joined: Wed Apr 05, 2017 12:49 am
Location: ARUP, amsterdam

Zero length elements with shear-axial interaction

Post by giovannimilan »

Hi all,

Is there anyone who attempted to create within a frame model, zero length translational and rotational springs in which the F-d (or M-rot) relationship depends on the axial load of the beam elements?

For instance, I am thinking about a moment frame with concentrated plasticity, in which the hinges behavior is updated during the analysis, depending on the axial load of the columns.

Cheers,
selimgunay
Posts: 916
Joined: Mon Sep 09, 2013 8:50 pm
Location: University of California, Berkeley

Re: Zero length elements with shear-axial interaction

Post by selimgunay »

We have previously developed a shear spring that considers the shear capacity-axial force interaction according to the Caltrans SDC and ACI318 equations. You can find the details in Chapter 6.2 of the report below. Please let me know if you have any questions.

http://peer.berkeley.edu/publications/p ... osalam.pdf
giovannimilan
Posts: 71
Joined: Wed Apr 05, 2017 12:49 am
Location: ARUP, amsterdam

Re: Zero length elements with shear-axial interaction

Post by giovannimilan »

selimgunay wrote:
> We have previously developed a shear spring that considers the shear
> capacity-axial force interaction according to the Caltrans SDC and ACI318
> equations. You can find the details in Chapter 6.2 of the report below.
> Please let me know if you have any questions.
>
>
> http://peer.berkeley.edu/publications/p ... osalam.pdf

Hi,

Thanks for the prompt reply.

I ve understood the yielding force updating before yielding.

However, I am thinking, is it a zeroLength in 2 directions in which you are actually reading the axial dof (elastic material for instance) and using it for updating the transversal dof properties(inelastic constitutive law material)?

or is it still only the trasversal dof (shear, no axial) but it is able to read in the force from the adjacent beam element for instance?
selimgunay
Posts: 916
Joined: Mon Sep 09, 2013 8:50 pm
Location: University of California, Berkeley

Re: Zero length elements with shear-axial interaction

Post by selimgunay »

It is the latter one, i.e. the trasversal dof and it gets the axial force from column that it is connected. The connected column info is provided as input.
giovannimilan
Posts: 71
Joined: Wed Apr 05, 2017 12:49 am
Location: ARUP, amsterdam

Re: Zero length elements with shear-axial interaction

Post by giovannimilan »

selimgunay wrote:
> It is the latter one, i.e. the trasversal dof and it gets the axial force
> from column that it is connected. The connected column info is provided as
> input.

Thanks.

I am assuming the equations are uncoupled in the vertical and the horizontal directions (since the spring does not provide entries in the matrix which are related to the vertical dof's). Hence, one is able to solve it first vertically to get the axial force and use this one to update the "horizontal" equation. Otherwise, I may think that is possible to use the axial force from the previous time step (as long as the time-step is sufficiently small).

Which do you reckon is more efficient?

I am working on my master thesis about masonry structures and representing the masonry piers behavior with ASCE 41-13 shear capacity (depending on axial load). Could you please provide a workflow example for the material model?
TPdct
Posts: 43
Joined: Thu Jan 21, 2016 5:51 am
Location: Dalian University of Technology

Re: Zero length elements with shear-axial interaction

Post by TPdct »

Do you have the source code of your proposed shear-axial interaction element (or material)?
selimgunay
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Joined: Mon Sep 09, 2013 8:50 pm
Location: University of California, Berkeley

Re: Zero length elements with shear-axial interaction

Post by selimgunay »

Yes I have it. I will look for it and let you know.
giovannimilan
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Joined: Wed Apr 05, 2017 12:49 am
Location: ARUP, amsterdam

Re: Zero length elements with shear-axial interaction

Post by giovannimilan »

selimgunay wrote:
> Yes I have it. I will look for it and let you know.

It would be great.

Cheers,
TPdct
Posts: 43
Joined: Thu Jan 21, 2016 5:51 am
Location: Dalian University of Technology

Re: Zero length elements with shear-axial interaction

Post by TPdct »

My Email: dct328@163.com
giovannimilan
Posts: 71
Joined: Wed Apr 05, 2017 12:49 am
Location: ARUP, amsterdam

Re: Zero length elements with shear-axial interaction

Post by giovannimilan »

selimgunay wrote:
> Yes I have it. I will look for it and let you know.

hello,

have you found the reference source code?

Cheers,
selimgunay
Posts: 916
Joined: Mon Sep 09, 2013 8:50 pm
Location: University of California, Berkeley

Re: Zero length elements with shear-axial interaction

Post by selimgunay »

I will send it to you within few days. Could you tell me your email address?
giovannimilan
Posts: 71
Joined: Wed Apr 05, 2017 12:49 am
Location: ARUP, amsterdam

Re: Zero length elements with shear-axial interaction

Post by giovannimilan »

selimgunay wrote:
> I will send it to you within few days. Could you tell me your email
> address?

It is: giovanni1.milan@gmail.com

Thank you.
basdekmara
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Joined: Wed May 10, 2017 10:12 am
Location: University of Patras

Re: Zero length elements with shear-axial interaction

Post by basdekmara »

Hi everyone,

does anyone have the source code of shear-axial interaction in a zero length element?

Thank you.
selimgunay
Posts: 916
Joined: Mon Sep 09, 2013 8:50 pm
Location: University of California, Berkeley

Re: Zero length elements with shear-axial interaction

Post by selimgunay »

Please indicate your contact email. I will send it to interested people soon.
TPdct
Posts: 43
Joined: Thu Jan 21, 2016 5:51 am
Location: Dalian University of Technology

Re: Zero length elements with shear-axial interaction

Post by TPdct »

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