Adaptive pushover curve not smooth

[R.K]

Hi there,
I'm trying to do an adaptive pushover analysis on a concrete frame building. I could get a nice smooth curve with a static pushover so I think the model itself is fine. However, with adaptive pushover, the capacity curve is not smooth but shaking up and down. I'm not sure how to post a picture here but the following is a section of the analysis log. As you can see the load factor fluctuates. Could you please help me to understand why this is happening and how to fix it?
Thx

Disp_Incr= 0.26615, LF= 5.00397 (Iter: 1 => Converg)
Disp_Incr= 0.26615, LF= 4.96043 (Iter: 1 => Converg)
Disp_Incr= 0.26615, LF= 4.99995 (Iter: 1 => Converg)
Disp_Incr= 0.26615, LF= 5.01849 (Iter: 1 => Converg)
Disp_Incr= 0.26615, LF= 5.13719 (Iter: 1 => Converg)
Disp_Incr= 0.26615, LF= 5.10053 (Iter: 1 => Converg)
Disp_Incr= 0.26615, LF= 5.10711 (Iter: 1 => Converg)
Disp_Incr= 0.26615, LF= 5.09956 (Iter: 1 => Converg)
Disp_Incr= 0.26615, LF= 5.20574 (Iter: 1 => Converg)
Disp_Incr= 0.26615, LF= 5.07270 (Iter: 1 => Converg)
Disp_Incr= 0.26615, LF= 5.33854 (Iter: 1 => Converg)
Disp_Incr= 0.26615, LF= 5.21573 (Iter: 1 => Converg)
Disp_Incr= 0.26615, LF= 5.24224 (Iter: 1 => Converg)
Disp_Incr= 0.26615, LF= 5.03837 (Iter: 1 => Converg)
Disp_Incr= 0.26615, LF= 4.91331 (Iter: 1 => Converg)
Disp_Incr= 0.26615, LF= 4.96578 (Iter: 1 => Converg)
Disp_Incr= 0.26615, LF= 5.02384 (Iter: 1 => Converg)

[seismosoft]

It seems that you probably need to set more stringent values to the covergence criteria norms.
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[R.K]

Thank you. It helps with some models, but in other models I got convergence problems:

Convergence not Achieved
Convergence Message: elm_Ite
-----------------
Displacement Norm: 0.00059104 / 0.01
Rotation Norm: 9.7316325E-005 / 0.01
-----------------

Element win137: elm_Ite

It's strange because it seems the convergence criteria I set has not been reached, but the software reported convergence problem here. Could you please suggest how to overcome this?

[seismosoft]

elm_ite is not related to the convergence norms.
Please read the relevant sections on convergence in the Users manual. Furthermore, there are numerous posts on convergence difficulites in this forum. If you carry out a search you will find plenty of information
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