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That's it! They are not scaled by g and the units are in metric.

Thank you very much, Dr. Silvia!

I forgot to mention that the model runs just fine when PEER GMs records are used. So, I know the problem is in applying the SAC GMs.

Dr. Silvia, I am also trying to run SAC GMs, but OpenSees gives me a convergence error at the beginning of the record (3.45 sec). The time step for input ground motion is 0.02 sec, and for the time-step Dt for lateral analysis I select a small value (as little as 0.00005 sec). I tried scaling down t...

OK. Thank you. I really appreciate your help!

Dr. Silvia, I tried your suggestion and I also tried defining a semi-rigid connection with zero stiffness. Both runs give me the same results. However, when I run the same frame on SAP 2000, the results differ by up to 7%. Do you think I have a problem in either SAP or OpenSees models, or this is a ...

Dear all,

Do you know where in the manual I can find a description on how to model pinned connections? I know the "fix" command would work if I am applying boundary conditions, but how do I model beam-to-column pinned connection?

Thank you very much!

Should I apply the load inside the loop so that controlTime can change and reach TmaxAnalysis?

I want to record the period at each time increment.

Thank you, Frank!

Dr. Silvia, it did work. Thank you! However, when I try the following (get the period at each time increment), my output file is enourmous (34 GB) set TmaxAnalysis [expr 1.]; set lambda [eigen 1]; # eigenvalue mode 1 set omega [expr pow($lambda,0.5)]; set PI 3.14159265; # Define Pi set Tperiod [expr...

OK. I will try it. Thank you very much, Dr. Silvia!

But where? I do not specify a file name.

Thank you, Dr. Silvia!

Dear all, I am modeling a 20-story frame and using the following procedure (as described in the manual) to obtain the building natural period: # ------------PeriodFreq&Damping.tcl----------------------------------------------------------------- # determine Natural Period, Frequency & damping...

Time is first. Then, you have the response for the first node as defined in the element (6 dofs), followed by the second node (6 dofs).

Does anyone know if modeling a frame using the Consistent Mass Matrix is possible on OpenSees? This is, applying the mass of the structure as a uniformly distributed mass rather than as a nodal mass.

Thank you,
Dobrinka Radulova

Graduate Research Assistant
The University of Texas at Arlington

Instead of using the following: # Semi-Rigid Conection equalDOF 1 3 1 2; uniaxialMaterial Steel02 1 1989 786732 0.1 20 0.925 0.15; element zeroLength 2 1 3 -mat 1 -dir 3; Try defining a section as follows: # Semi-Rigid Conection equalDOF 1 3 1 2; uniaxialMaterial Steel02 1 1989 786732 0.1 20 0.925 0...