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Hello! I’m working on a 3d structure similar to example 5. I’m using eleload type beamuniform for gravity load, but I get an error message (expected integer but got “-type”). Anyway gravity load anlysis run, axial force on the pillars is right, but I obtain a big axial force on the beams and this is...

Hi everybody! I’m working on a 3D pushover analysis. I found that if I build the pushover curve using the roof displacement in x axes and the sum of the base shear in the pillars in y axes, I obtain slightly different results from the ones I obtain using the load factor multiplyed for the sum of the...

Hi! I’m checking the results of dynamic analysis on a Three-Dimensional Elastic Frame. The model consists of four stories and one bay in each direction with elasticBeamColumn elements for pillars and beams (beams have very big values of E G J Iy Iz). I can’t find a maximum displacement similar to th...

(Thanks Silvia for your answer about distributed loads, it was right!)


Hi all!
How can I know the value of force quantity in internal section of elastic elements (element elasticBeamColumn...)?
Thank you.

Hello! I’m trying to use command eleLoad on a 3D structure, but it doesnt’work. The message I get is: expected integer but got “-type”. Even if the anlysis run I don’t obtain good rusults. I insert here two simple examples: 1) a portal with a distributed load on the beam doesn’t give the right Axial...

Hello!
How can I put distributed loads on beam elements?
Thanks a lot.

Hello! I’ve three quetions about modal analysis in 3D. 1) In 3D I found that also simple symmetric structure have the first eigenvectors with component in all direction (One of these is dominant, the other much smaller). I expected that only one component was different from 0. Why isn’t it so? 2) Wh...

Hello!
I need to calcolate the participation factor.
Is there anybody who made a procedure for this scope?
How can I assign an eigenvector component to a variable?
Thank you.
Best regards.

Hello! I’m studying a simple Three-Dimensional Rigid Frame, similar to example 5 of “Open Sees Examples Primer”. As in example I used rigidDiaphragm 3 9 5 6 7 8 fix 9 0 0 1 1 1 0 and in this way dynamic analysis run. If I cancel fix 9 0 0 1 1 1 0 the analysis fail. Do you know why? Is it possible to...

Hi all users! I have a problem with eigen values analysis in a simple 3D example. Also in 2D examples I can't find all eigen values thai I expected, I think because the last are less important (is this right?). But in 3D I can only obtain the first eigen value. My example is: # OpenSees TELAIO 1p an...

Hi all users! I have a question about the command: rayleigh $alphaM $betaK $betaKinit $betaKcomm What is betaKcomm? I think it is the stiffness matrix at last-committed state of the dynamic analysis, but, if so, how can be known by the program before doing the analysis? In some examples rayleigh is ...

Hello! I’m studying example 3.3 of “Open Sees Examples Primer”. How can I record the shear in the columns during the dynamic analysis? If I use “recorder Element -time -file ele1secForce.out -ele 1 section 1 force” I obtain only the moment and the axial force. Thank you for the attention. Best regar...