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hi all, I have a problem during modal analysis, the structure period is always wrong , could anyone knows how to do the modal analysis? why the period is wrong? Anxious for solutions, sorry for my English,thank you.

[quote="fmk"]if all your base nodes are constrained, it means you may be missing some elements .. start by constraining everything and then removing constraints until you find the source of your error.[/quote]

Got it.Thank u.

[quote="fmk"]you don't have enough constraints[/quote]
Thank you for your reply, I constraint the basenodes, others are default. Is it right? Could you explain it in detail? Thank you for your patience and sorry for my English.

hi all, can u tell me what does this information means:
UMD2FA: matrix is singular,only 432 pivots found.WARNING UmfpackGenLinSolver::solve(void) 4 returned in factorization UMD2FA().
thank u!

[quote="basir"]hi i will share a complete script with you all which is single run an perform an adaptive pushover procedure using opensees and tcl features.[/quote] Dear basir, do you have some information about Adaptive Pushover ?? can you share it with me. I would like to learn it and I ...

[quote="fluozhen"][quote="pankotso"]Hi all, I tried to modify the example 1 given in quickmain in opensees source with a basic example (like example 2) with elastic beam elements. My problem is that when i try to build the solution, the compliler says that ''Cannot open include f...

Hi all, does anybody have a manual of opensees for C++?? I met many problems for pushover analysis in C++, could anyone give me a manual if it exists or some examples. Thank you so much.

[quote="pankotso"]Hi all, I tried to modify the example 1 given in quickmain in opensees source with a basic example (like example 2) with elastic beam elements. My problem is that when i try to build the solution, the compliler says that ''Cannot open include file: 'ElasticBeam2d.h': No s...

[quote="fmk"]what do you mean the K is 0, if you mean your stifness matrix is all zeros, and you have elements, it means your material properties or section definition is incorrect. if the matrix is singular, i.e. there are values in it, then you have the problem above or not enough constr...

when I do some eigenanalysis there's something wrong:
the eigenvalue is numrically undetermined or infinite, but the K is 0 when I output it, I don't know what the problem is? Why the K is 0? Please help.

[quote="fmk"]well if your stiff is 0, you have to change your input parameters.[/quote]
thank you for your patience.

[quote="fmk"]the force beam column needs to iterate at every step .. it does a newton iteration using the flexibility matrix, if that fails it does some modified newton iterations and tries cutting the step size. your element is failing in these iterations which typically means that 1, tho...

"WARNING - ForceBeamColumn2d::update - failed to get compatible element forces & deformations for element: "(dW: << " << dW << ")\n";

I really don't know why is that? please help!!!!!!!



Many thanks.

[quote="fmk"]the debugger should be able to tell you the line nu .. if not do some manual debugging by putting stuff like opserr << "HERE -1\n" in the source code to see what the offending line of code is.[/quote] Dear fmk, Thank u for your patience and guidance, it is probably a...

[quote="fmk"]what line does the error happen .. and do you not have access to a debugger! .. if you are planning on writing code you need to have access to a debugger and you need to know how to use it![/quote] dear fmk,thank u for ur reply. I debug the code and the mistake happened on thi...