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I briefly looked into the source code for 3D corotational transformation. I found in the CorotCrdTransf3d.cpp that rigidoffsets are set to be zero in the constructor regardless of input command. // constructor: CorotCrdTransf3d::CorotCrdTransf3d(int tag, const Vector &vecInLocXZPlane, const Vect...

I found that the program stopped during eigen analysis when the number of elements is greater than a certain number. For example, when I tried more than 1000 elements for 3D 4 story building frame with the lumped masses on the leanon column, the program stopped abnormally with the message that I des...

Hi Fmk I built a 3D frame model for OS2.0.0. I found this model seems working fine (producing at least reasonable eigen values) when the model has 4 story 2bays per each perimeter. However when I increase the number of elements, I 've got error message saying "the application has requested the ...

I tried MultipleSupport to impose bi-directional displacement history to a node long ago. # impose displacement history set dispSeriesX "Series -fileTime time.txt -filePath pathX.txt" set dispSeriesY "Series -fileTime time.txt -filePath pathY.txt" pattern MultipleSupport 1 { grou...

Hi, User, I encountered a problem with rigid offset in 3D corotational transformation. I am in the middle of creating a 3D frame model. Before creating elements, I checked whether nodes and geometric transformation were properly defined. I used Corotational transformation with jntOffset option but O...

Hello, I have a question regarding series of earthquake analysis. What I want to do is to study the effect of aftershock. To do that, I first apply 1st ground motion record to a frame. After 1st record, I apply static correction by performing static analysis with dummy load at any arbitrary node. Th...

hello users I am trying similar things you guys did here. I simulate the fracture of pt bar in my model so I use "remove" command to eliminate the pt element during analysis. But I have a question regarding recorderTag shown in the code ca493 posted above. I can successfully remove the ele...

thanks Silvia,

I downloaded it again and compiled it to a release version. It works fine now...

Hi, users I have zerolength elements in my model and output the force into file. I am using two OS2.0.0 versions, one is a release version and one is a debug version. Those two versions were compiled on my PC. For some reasons, a release version could not output the zerolength element forces correct...

For transient analysis, why don' you try unbalanceIncludingInertia at the node you want to get restoring force? I am not sure it is a correct way. But in my case, I have a 2-D bracing frame to get story shear at each floor. So I used the command at each node and compare the force in horizontal direc...

Anybody tried explicit method for nonlinear transient analysis?
For implicit method, it is working fine but by switching to explicit method, the SOE seems to have zero diagonal terms. Why does this thing happen?

Dear user, I tried to compare implicit and explicit methods for a transient analysis. For some reasons, I have stability problems with explicit method. No matter how small time step I chosed, it always blew up in a very few seconds or fails even at the first time step. For example, I tried the examp...

yes, I did it with -time before but had same problems. Besides, I run OS in XP.

Thanks silvia,

It runs without any problems and the results seem to be fine though, Do I really need to run the analysis twice??

I defined an initial strain at the EPP material used for truss element.
You can also use displacement beam column element for PT by imposing end moment release.