The OpenSees Community

Hi,

is it possible to change the opensess source and add a new algorithm command in opensees?

Thank you.

Hi,

Would you please tell me there is the infinite element for soil model in opensees?

thanks.

I think we should use mass command for dead weight of elements (p*A*L)+DEAD+20%LIVE; and
we use load command for DEAD+100%LIVE.

Dear silvia, which opinion is correct? me or esi_opensees?

tnx

Hi all

would you please tell me how we can determine the plastic rotation of elements?

Thanks

Hi,

Would you please tell me what is probability of exceedance in the PEER Strong Motion Database?
10% PE in 50 yrs OR 5% PE in 50 yrs OR 2% PE in 50 yrs?

Thanks.

Hi all I modeled this structure (2D) with "nonlinearBeamColumn element" instead of "truss element" and I used equalDOF to release of the moments at the ends of elements with the exception of columns. But when I run the script, this error message appears; WARNING BandGenLinLapackS...

Dear Silvia

what is large displacement for any kind of structures? it is different for any one. can opensees check stiffness matrix whether at any load increment it becomes negative? if so, how?

Thanks

Hi all I want to determine the ultimate load in nonlinear static analysis, without considering the displacement control because I don't know what is the displacement corresponds to ultimate load. As you know, during the nonlinear analysis iteration, the determinant of the overall stiffness matrix is...

OK, I put two nodes at the same location for participant nodes of truss and column (nodes 1,3) node 1 -2 3 node 2 0 3 node 3 2 3 node 4 -1 5 node 5 1 5 node 6 -2 0 node 7 2 0 node 11 -2 3 node 33 2 3 #------------------------- fix 1 0 0 1 fix 2 0 0 1 fix 3 0 0 1 fix 4 0 0 1 fix 5 0 0 1 fix 6 1 1 1 f...

Dear silvia, First of all, thank you for your consideration, but below problems bring up: 1.why do you constrain only nodes 2,4,5 ? 2.when we constrain the rotational dof at only nodes 2, 4, 5, the support nodes (6,7) are unconstrained, so the all outputs(forces,displacements) are zero in dynamic an...

Dear Dr.silvia

I checked the model again, but opensees gives those messages.
If you look the model with OSP, you will observe that node 6 & node 7 constrained.
Would you please help me?

Hi, I modeled a simple 2D structure. 7 elements are truss and 2 elements are column. I'm trying to do nonlinear time history analysis, but when I run the script, this error message appears; WARNING BandGenLinLapackSolver::solve<> -LAPACK routine returned 3 WARNING NewtonRaphson::solveCurrentStep<> -...

Dear friends I had a question and I would be grateful if you could answer me. I am trying to model a 3-D structure that some elements are truss and some of them are frame elements. Since for truss: ndm=3 ndf=3 and for frame: ndm=3 ndf=6, what is -ndf in " model BasicBuilder -ndm 3 -ndf ? "...

Hi all,

recorder command creates rows of outputs, Is it possible opensees creats them columnar? if so,would you please tell me how can I do it?

Thanks

Hi all,

I want to know how to use opensees to do IDA.
Would you please give me some help and examples?

Thank you in advance.