Seismosoft | Earthquake Engineering Solutions

Dear seismosoft,
I created a simple RC beam based on an experimental test. This beam is restrained at the start and at the end in all of degrees. The reinforcement is different in top and bottom at the start/end and at the middle. For these different between reinforcement, first, I divided the length of the beam to three parts:
First 0.15 L, 0.7 L, the last 0.15 L.
Because there is a need to define load point at the middle, the 0.7 L also divided to two parts. Therefor, the beam are four parts until know.
Also, because we want to extract the vertical displacment at the 0.25 L from both side, two new nodes were also defined and finally the length of the beam were divided to six parts with five points.
After pushover, based on the defined criterias, it seems that the reinfocement in two middle parts were reached to yeilding, and only concrete covers reached to crash. But, the analysis was not continiue to crash the concrete core and it was stopped. Could you please help me for this issue? Do you think that the beam is unstable because of too many nodes and parts( I use infrm element)?

It is also mention that this beam did not reach to the vertical target load (which is determined by experimental test).

You need to refer to the program manual / help and to our YouTube channel for information on how to solve convergence difficulties. If you carry out a search on the forum you will also find plenty of resources. One additional note is that with six elements for one members you probably need to use the infrmDB, rather than the infrmFB element type. With the latter you have 6*5=30 integration section which is both excessive and makes it hard for the model to converge.

Seismosoft Support

Thank you seismosoft. I change element type from infrmFB to infrmDB. My model was analyzed well.