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hi
I have this error in my model. would you please explain about the reason of that?
WARNING BandGenLinLapackSolver::solve() -LAPACK routine returned 1

I can send the scripts to check if needed
Thanks in advance

Hello everybody
I've studied some articles about modeling braces in OpenSees considering initial imperfection,but the imperfection size was different.some of them assumed to be L/250, some of them L/1000 or L/500. what's the reason of this difference?
thank's in advance.

hello everybody
I'm considering imperfection in my braces,but I don't know about the direction of these added nodes ?for example If I want to consider l/1000 for an initial imperfection,I should use positive buckling or a negative one ?
thanks in advance

hello everybody my case study is progressive collapse and the forces were increased linearly for five seconds until they reached their full amounts, kept unchanged for two seconds until the system reached stable condition In my model but I have a problem in the part that I should increase loads line...

hello dear all I,ve modeled two elements for each brace for considering buckling.now I,m going to remove some elements like a column and the related brace ,before analyzing.but I don,t know should I remove both of the brace elements or only the single element of the brace that is connected to the co...

hello everyone An Eccentrically braced frame has been subjected to The quasi-static loading protocol based on the guidelines presented in ATC-24.I saw this example: http://opensees.berkeley.edu/wiki/index.php/OpenSees_Example_4._Portal_Frame there,s a vector of displacement-cycle peaks in this examp...

thanks dear fmk this is the script: set filename "5story-3bay element 10" ; set File1 "$filename/PeriodMode1.txt" ; set File2 "$filename/PeriodMode2.txt" ; set File3 "$filename/PeriodMode3.txt" ; set File4 "$filename/PeriodMode4.txt" ; file mkdir $fi...

hi dear all I,m removing vertical elements for analyzing in my model.but when I remove the top column and the nodes are connected to it ,OpenSees gives this error: the Opensees has stopped working the column nodes are not connected to other elements (my model Connections are Hinged)and this error on...

hello dear all

WARNING BandGenLinLapackSolver::solve() -LAPACK routine returned 1
does the number of this warning at the end of that have specified meaning?

thanks

thanks for your kind help but when I want to remove the top column of my model and the brace connected to it and the nodes connected to them that are not connected to another element I have this warning: OpenSees.exe has stopped working and I only remove the column ,the brace and two nodes . the top...

Thanks dear fmk how can I solve this problem?I have to remove some elements before analyzing because I,m studying on it.all of my connections,except Braces connection are hinged. These are my model Codes: wipe all; puts " " puts " " source Bsection.tcl; source Wsection.tcl; model...

hello everyone I tried different algorithms in order to analyze my model .but after removing element (removing is because of progressive collapse) in Time history analysis ,this warning will happen.would you please guide me to solve that? Starting OpenSees.. *****************************************...

hello dear all I,m doing Time history analysis after removing column from my model.but I expect, axial loads of the other columns settle down at a steady value after some time.but it does,nt happen and changes all the time during the analyzing.would you please tell me the reason? these are my model ...

thanks dear mhscott
how many iterations do you suggest?I gave 100 iterations but It does,nt converge !

hello dear all I,m going to do time history analysis after 7 seconds doing static analysis with 0.01 time steps but it does,nt converge .but when I change it to 0.001 time steps it does,nt have any problem.Is there any way that it converges in 0.01 time steps?! this is my model: wipe all; puts "...