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Thanks. This occurred to my mind too. I suspected that plain pattern might not work properly with transient analysis and Newmark integrator. They are irrelevant matters; aren't they? I assume by load pattern command you meant Plain pattern.

Hi All, I was wondering how we can apply a variable load pattern on any desired node on the structure. Imposed motion in connection with ground motion commands are not any good since they only apply velocity, Acceleration and displacements. I want to perform the same function as the ones imposed mot...

Force beam column takes advantage of forced based shape functions which is more robust that displacement formulation.

Hi,

I would like to receive nodal forces for my element.
Is there any public function for getting forces from the nodes at committed steps? Most functions seem to be private

Thanks. It indeed worked with OpenSees 1.7.3 and 2.2.0 very well. However, a message appears which is unknown to me WARNING: GroundMotion::getDisp(double time)-integration is required to get the ground displacements from the ground velocities. Let me mention that I did add trap ezoidal integration f...

Is there any object pointer referring to displacements at every committed step?
I think I can do the same thing as recorder command does. The only problem is I dont know how recorder command functions?
How can I save the displacements of my element in C++?

Actually I was not asking about tcl-opensees commands. I did not mean to use recorder command to record the displacements of my previously-made model. I am developing a new elastic-perfectly plastic element. My element functions well in monotonic loading but I somehow encountered a problem in unload...

Wont I encounter rigid-body motions and subsequently non-convergence if I free the supports? Based on what you stated, If two simultaneous (vertical and horizontal) velocity ground-motions should be applied on supports using ground motion command, two out of three DOFs should be freed in fully fixed...

Frank, I am about to develop a 2D bi-linear elastic perfectly plastic spring type element which works with force-deformation or moment-rotation relationships. In order to track the entire hysteretic behavior in a full cycle, I need to record the displacements and/or deformations of the current step ...

Hi everybody, I have a 2D moment resisting structure with fully fixed ground supports. I would like to apply a horizontal as well as a vertical [b]velocity time history[/b] ground motions on the supports. Can I do this via multiple support pattern in combination with imposed and ground motion comman...

Thanks,
I have sent an Email in which all descriptions are available including .cpp, .h and an explanatory pdf file as well as some tcl codes.

Dear Zhang, Good to hear that. Currently, I am waiting for Frank to just give me an Email address by which I can send my files to him. As soon as he does so, I will report any bug and we will try to finalize the files. Then I will be able to contact with you for further share of information and expe...

[b]Dear Frank,[/b] We have finally managed to compile our codes in OpenSees and added an element of our own. The Element is TubularJointElement which is capable of local joint flexibility inclusion in offshore structures. We have also validated it by using more sophisticated FE codes such as Ansys s...

Thats right
Using Tcl you may be able to do most necessary modeling techniques you need except for those capabilities which do not exist in the current code.

I have been working with OpenSees since 4 years ago and I am a little familiar with PSSI. However, in "soil modeling" room you may find a lot of people working on soil modeling and simulation who are more professional. I understand that working with user-friendly softwar is way more profit...