The OpenSees Community

In his name is the judge Hi I think the best way to assign the nonlinear effect of steel components like beams that to model it with a plastic hinge. So To build a nonlinear model of a one-story steel structure I use the Modified Ibarra – Krawinkler model to model my beam. In fact, I model a beam wi...

thanks fmk and prof scott

i Awared that we can only use two modes parameters for Rayleigh Damping because of it's coding on opensees and also because of it's definition.

wish you best.

deer prof scott i did that in my code but when i ran the model i face this error " ArpackSolver::Error with _saupd info = -9999 Could not build an Arnoldi factorization.IPARAM(5) the size of the current Arnoldi factorization: is 3factorization. The user is advised to check thatenough workspace ...

thank you so much i found a code for rayleigh damping in tcl editor, " set xDamp 0.02; # damping ratio set MpropSwitch 1.0; set KcurrSwitch 0.0; set KcommSwitch 1.0; set KinitSwitch 0.0; set nEigenI 1; # mode 1 set nEigenJ 1; # mode 3 set lambdaN [eigen [expr $nEigenJ]]; # eigenvalue analysis f...

Hi I had a questiones about the operation of the Riley damping command in Opensees. First, how does the Rayleigh Damping Command affect the damping in any structural mode? Second, can the Rayleigh Damping Command be set to affect only certain modes of the structure? Any help is greatly appreciated I...

hi my thesis is about new damper named tlcgd (tuned liquid column gass damper) wich has a special damping coefficint and stiffness coeeficinet in it's equation of motion. i tried to model damper with using viscouse damper material and two node link element. first i evalute damper coefficinet in damp...

dear all i think make a progress with this question. i used two change wich think make better result. first i used rigidLink beam between cm and each node insted od rigid diaphragm command. second i used Elastic TimoshenkoBeam insted of elastic element or other type of element and it also made me be...

dear selimgunay
i used this command for my model but it didn't work.
also when i assign mass to center of mass, i get more far result.
wish you best

dear prof scott
thank you so much for offering that post i'm afraid it didn't helpful.
wish you best

hello everyone, i'm trying to model a 3D one story buiding with mass IIrregularity, the model has 4 elastic columns and rigid diaphragm. the model has no beam, so i used rigid diaphragm to equal dof of top nodes of columns. i use a model from a reasercher's article, he note that the modal frequences...

hello everyone, i'm trying to model a 3D one story buiding with mass IIrregularity, the model has 4 elastic columns and rigid diaphragm. the model has no beam, so i used rigid diaphragm to equal dof of top nodes of columns. i use a model from a reasercher's article, he note that the modal frequences...

hello everyone, i'm trying to model a 3D one story buiding with mass IIrregularity, the model has 4 elastic columns and rigid diaphragm. the model has no beam, so i used rigid diaphragm to equal dof of top nodes of columns. i use a model from a reasercher's article, he note that the modal frequences...

hello
you can use "print A" command to get mass matrix and eigenvectors
https://opensees.berkeley.edu/wiki/index.php/PrintA