When modelling the mechanical performance of RC structural members, if the Concrete02 material is employed, the problem encountered most frequency is the convergence, one will always get "analyze failed", no matter the force based element is employed nor the displacement based element.
So, can anyone tell why the convergence of concrete02 material is so bad? Is there any technique to improve the convergence?
why the convergence of concrete02 so bad?
Moderators: silvia, selimgunay, Moderators
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selimgunay
- Posts: 916
- Joined: Mon Sep 09, 2013 8:50 pm
- Location: University of California, Berkeley
Re: why the convergence of concrete02 so bad?
Convergence performance directly depends on the specific parameters of the problem. What are you using Concrete02 for and what is your ultimate strain. Could you provide the details of your section?
Re: why the convergence of concrete02 so bad?
selimgunay wrote:
> Convergence performance directly depends on the specific parameters of the
> problem. What are you using Concrete02 for and what is your ultimate
> strain. Could you provide the details of your section?
Thank you for your reply.
①I try to see the effect of Concrete02 under different loading situations.
②Does 'the specific parameters' you mentioned is the parameters for concrete02?
③The ultimate strain is calculated by 0.004+0.9*$rho*$fyh/300, where rho is the hoop volumetric ratio, fyh is the strength of hoop.
④Does a bigger ultimate strain can improve the convergence?
> Convergence performance directly depends on the specific parameters of the
> problem. What are you using Concrete02 for and what is your ultimate
> strain. Could you provide the details of your section?
Thank you for your reply.
①I try to see the effect of Concrete02 under different loading situations.
②Does 'the specific parameters' you mentioned is the parameters for concrete02?
③The ultimate strain is calculated by 0.004+0.9*$rho*$fyh/300, where rho is the hoop volumetric ratio, fyh is the strength of hoop.
④Does a bigger ultimate strain can improve the convergence?
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selimgunay
- Posts: 916
- Joined: Mon Sep 09, 2013 8:50 pm
- Location: University of California, Berkeley
Re: why the convergence of concrete02 so bad?
Yes the larger ultimate strain will improve the convergence, but I experience a bit difficulty in understanding the objective of exploring Concrete02 under different conditions, because this is difficult to isolate, convergence depends on other factors such as the reinforcement, whether there is enough confinement for the core concrete, section geometry, element type (force-based vs disp based), etc.
Re: why the convergence of concrete02 so bad?
selimgunay wrote:
> Yes the larger ultimate strain will improve the convergence, but I
> experience a bit difficulty in understanding the objective of exploring
> Concrete02 under different conditions, because this is difficult to
> isolate, convergence depends on other factors such as the reinforcement,
> whether there is enough confinement for the core concrete, section
> geometry, element type (force-based vs disp based), etc.
I am very appreciated for your explanation. Maybe I should reconsider the questions that I encountered. Thanks again.
> Yes the larger ultimate strain will improve the convergence, but I
> experience a bit difficulty in understanding the objective of exploring
> Concrete02 under different conditions, because this is difficult to
> isolate, convergence depends on other factors such as the reinforcement,
> whether there is enough confinement for the core concrete, section
> geometry, element type (force-based vs disp based), etc.
I am very appreciated for your explanation. Maybe I should reconsider the questions that I encountered. Thanks again.