Convergence issue in moment curvature example

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Convergence issue in moment curvature example

Postby ismailqeshta » Fri Aug 10, 2018 6:21 am

Hi,

I have run the Moment Curvature Example for my column section at different axial loads and obtained reasonable results.

I, then, ran exactly the same model for another material, but I keep getting convergence issues.

In both examples I used ductility factor of 25 and number of increments of 100.

If anyone can help me with this problem, that would be greatly appreciated.

Thank you very much.
ismailqeshta
 
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Location: RMIT University, Melbourne, Australia

Re: Convergence issue in moment curvature example

Postby kesavapraba » Fri Aug 10, 2018 8:23 pm

Dear Friend, You can try different algorithms and displacement increment steps in your analysis section. Can you tell me the different materials that you used?
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Re: Convergence issue in moment curvature example

Postby ismailqeshta » Fri Aug 10, 2018 8:32 pm

Hi,

Thanks for your suggestion.

I am trying Concete 01 and Confined Concrete 01.

I am using the following algorithm (units are in N, mm, sec and tonne):
integrator LoadControl 0.0
system SparseGeneral -piv; # Overkill, but may need the pivoting!
test NormUnbalance 1.0e-6 10
numberer Plain
constraints Plain
algorithm Newton
analysis Static
ismailqeshta
 
Posts: 75
Joined: Mon Feb 20, 2017 1:19 am
Location: RMIT University, Melbourne, Australia

Re: Convergence issue in moment curvature example

Postby selimgunay » Fri Aug 10, 2018 8:54 pm

Please try concrete02 and steel02
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Re: Convergence issue in moment curvature example

Postby ismailqeshta » Fri Aug 10, 2018 9:13 pm

Hi Selim,

Many thanks for your suggestion.

I tried another model with concrete 02, and it worked.

Unfortunately, I need to obtain the moment curvature for concrete 01 and Confined Concrete 01, as my column is modelled using these two materials. I am using hysteretic material for steel.
ismailqeshta
 
Posts: 75
Joined: Mon Feb 20, 2017 1:19 am
Location: RMIT University, Melbourne, Australia


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