The OpenSees Community

Dear all, I am going to model a steel frame for optimization analysis of its braces. For this purpose, I shall firstly fill the supposedly braced bays with plane elements and then run the structure. Then, each time I run the analysis, based on some criteria, some elements will be eliminated until wh...

Dear all,

Is there a subroutine already prepared including Stahll profiles for the sake of analysis of steel members and frames? How can I have access to it if any?

Thanks a bunch,
Behtash

Dear Dr. Mazzoni,
How can I download, launch and use Buildong Tcl? I tried to, but I couldn't! Is there a special way for it?
My best regards,
B. JavidSharifi
SUTech

I meant OpenSees seemingly does not specify or give a hint about the probable location of plastic hinges and I'll need to figure it out manually. I was trying to ask for confirmation! Also, I believe I have seen a command like plastic rotation somewhere in codes I have already inspected. But I cant ...

Thank you. so the model I have prepared with nonlinearBeamColumn is probably suitably working. I shall check rotation at critical points manually chosen (middle and end points), is it right?

Couldn't you plant the UCD elements directly under base nodes and tie the horizontal movement of all base nodes to a totally fixed one? Then I suppose you may have to model the properties of the soil under each node specifically based on characteristics there (in case at hand) in order to account fo...

Thank you very much. so I should first know the rotation corresponding to yield values, and then record the rotation after analysis and compare them with those values. I want to check this for all beams and columns. Which element types are the most suitable for doing so? BeamWithHinges? Or nonlinear...

Dear all,
What is the fastest way to find out plastic hinges formed in the structure after a dynamic or pushover analysis?
Regards,
B. JavidSharifi

I believe it'll be OK, but pointless! The ShallowFoundationGen command does it exactly the same as you may need to. It also takes into account the zerolength elements wherever needed, as well as setting the distances of elements logically. Have you had a look at the subroutine created after this lin...

I meant so too. I just couldn't have gotten truss elements to work so far. but I finally will!
Thanks for the script,
All the best
Behtash;
SUTech

Seems there was sth wrong with truss elements! I did it with elasticbeamcolumn and nonlinearbemacolumn and worked!

It is a simple model! just a small truss. I double checked the supports. What may it be?! Seems something goes wrong with the linear algebra package. But I just cant get what is wrong!

Dear Ameri, I corrected the commands as explained in the conversations. But a problem still persists. The analysis fails at the very first step. The error appearing is this: WARNING BandGeneralLapackSolver: : solve() -LAPACK routine returned 2 WARNING ModifiedNewton : : solveCurrentStep() -the Linea...

Thank u so much. I found the answer in topics u sent.
Best regards,
Behtash

For a truss this:

element truss $eleTag $iNode $jNode $A $matTag <-rho $rho> <-cMass $cFlag> <-doRayleigh $rFlag>

is used. But still for a hinge among rigid connections e.g. in a frame I am wondering what to do!