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pushover analysis sap2000 v17.3.0

pushover analysis sap2000 v17.3.0

pushover analysis sap2000 v17.3.0

(OP)
Hello to everyone,
I'm new in this forum and this is my firs thread. Could anyone help me?
What i'm trying to do is to run a push over analysis on a structure, to check if the capacity design that i made before is correct, in order to recognize informations that i can use for a better proportion of members as well as to determine which could be the maximum directional displacement that the structure can handle until collapse.
In this model i want to simulate the post-yield behaviour by assigning concentrated plastic hinges to the frame elements, so i defined for every hinge type its limit states (IO, LS life safety, CP collapse prevention,..)
I am expecting to see the first CP hinge (green/yellow hinge), but the analysis seems locked until the life safety step (blue hinge) as you can see in this screen:
https://www.dropbox.com/s/r0n1ltm03mztaem/Screensh...

I made different tests but at the end of the analysis the .LOG text file shows many warnings like this:
"Maximum number of null steps reached",
"maximum number of total steps reached",
"the analysis cannot find a solution at step <number of step>";

This is the .log text file:
https://www.dropbox.com/s/7fn61fykkwmz202/prova%20...

So I tried to increase the parameter values as shown below, but the analysis goes beyond very slowly: only few steps and it takes a lot of time, like 15 hours!!:
- minimum number of saved states (from 10 by default to 100)
- maximum number of saved states (until 5000)
- maximum total steps per stage (from 200 by default until 2000)
- maximum null (zero) steps per stage (from 50 by default until 5000)
- max constant-stiff iteraction per step (from 10 by default until 20)
- max newton-Raphson iterations per step (from 40 by default until 60)
Here you can find a dropbox link of the model:
https://www.dropbox.com/s/dq567o2knc0z9d4/model4.r...

I think there are some convergence issues, but I don't know what else to do. Thanks in advance for your help!!







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