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Hi. Please help me. I model a 2D X braced steel frame. I used "Steel02" Material for all of elements and I used Fiber section for beams, column and braces. For buckling of braces, I used an imperfection in middle of element. Now after pushover analysis, my Pushover curve have one elastic segment and...

thanks for nice reply. But when I use those recorders as you said. I have 2 output files with only time column and I think opensees doesn't know them?

thanks, Please Post it, it will be useful for me.

thanks for nice reply, as I said, I use nonlinear beam column element for braces and divided it to two element for applying imperfection in my 3 story braced frame. when I use this records for each of 2 element of one brace and draw Axial force- elongation of each brace under the seismic record, I e...

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Hi Please help me about my question I model an X braced frame with 3 story. for brace element I use nonlinear beam column element and divided it to two element for applying imperfection (for modeling Buckling) Now how can I draw Axial force- elongation of each brace in stories of frame. can I use th...

Thanks for nice reply
In fact I use this for X brace element, when I try it with only steel02 or with steel 02 and positive initial strain, it converged . but in negative initial strain the model did not converge

Hi
can I use " initial Strain material" with a negative initial strain? such as following:

uniaxialMaterial Steel01 1 2.454e8 2.1e11 0.02
uniaxialMaterial InitStrainMaterial 3 1 -0.00015

my model dose not converge?

thanks a lot for your nice reply.
What are the parameters y & z in [eleResponse $ele1 section $sec1 fiber $y $z strain]?
and could I use this method for increasing amplitude of force instead stop analysis?

Dear fmk
How can I define a limit strain for one element to stop the alysis until reaching this limit.
regards

Dear Dr fmk
thanks for reply.
I tried it again as you said but I get the same output.

Dear Dr fmk Hi I modeled a brace frame with "selfcentering" behavior. In fact for only tension behavior, I omitted negative part of this material and add a new material with dll file. I verify my new material with a result test and it works correct. Now in my more analysis with earthquake, when I dr...

Dear Dr fmk Thanks for nice reply that the braced frame have X brace and element 5 is one of the braces. braces consist of two segments : rigid bar and an SMA brace ( nonlinear beam column with selcentering material and fiber section) some time when I increased "number of subdivisions (fibers) in th...

dear Dr. fmk thanks for nice reply But when I use this method as you said: "wipe model basic -ndm 2 -ndf 3 node 1 0. 0. node 2 0. 2.305 node 3 0. 2.564 #(top point) node 33 0. 2.564 #(for pinned connection Brace-column) node 4 1. 2.564 #(top point) node 44 1. 2.564 #( for pinned connection Beam-colu...

hi
I am some problem in convergence of a SMA braced frame.
which one parameters are effective in convergence to I change them.
I usually try analysis motor parameter and integral point in section.
but sometimes they are not effective.
do you have any recommendation?
thanks a lot