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Hi all, I'm sorry to post this simple question, but I'm a bit confused with the relative and absolute displacement and acceleration. I defined an acceleration and force in the following manner. What will be my recordings, absolute or relative?? Forces are defined as a product of mass and acceleratio...

Dear xiell, Thank you very much for your introduction new shear wall model. I've tried to use your model. I'm modeling a 10 storey RCC framed building with shear wall in some sections. I'm wondering that what should be the maximum size to descritize the wall element by your multi-layer shell element...

Thank you very much. I got it. But I've a small problem again. When I make a group of elements using region command and use it to define the recording the element forces, I got 12 no. of forces per element. As I have a 3D model, it should only be 6 forces per element. So my question here is how can ...

Hi all,
How can I record the shear force at each story for displacement control pushover analysis? I tried with the recording node reaction but got a very different result.

I objective is to make a graph of shear force vs intra-storey drift.

Thanks in advance..

Thank you very much alikmo. This will be helpful for me a lot. In the above question, yield properties means that which elements are behaving within elastic range and which are behaving beyond yielding point (inelastic) at what time with different types of loading (e.g with and without soil structur...

Dear all, I've a 3-dimensional nonlinear model whose elements are modeled with fiber elements. There are many fiber elements in one section; for example-reinforcements, concrete (confined, highly confined and unconfined) & steel sections modeled with many fiber elements and sections are differen...

Dear all, Here, I've two questions; 1) Is there any command or method to apply multi-directional (3-D) earthquake ground motion to the 3-D structure? I found the method only applicable for two directional input. 2) I've a model of a building with foundation. Foundation is modeled with spring-mass-da...

Although I couldn't understand your question clearly, find this example in OpenSees site which uses fiber element for the reinforcements of the RC section. http://opensees.berkeley.edu/wiki/index.php/OpenSees_Example_8._generic_3D_Frame,_NStory_NBayX_NBayZ,_Reinforced-Concrete_Section_%26_Steel_W-Se...

Can you upload your whole program?

The answer to the first question is "YES". You can define nodes with different dofs. You can define the dofs for each node by fixing it (by 1) or free it (by giving 0) in each direction. For example; model BasicBuilder -ndm 3 -ndf 6 node 1 0 0 0 node 2 1 1 1 node 3 2 3 2 fix 1 1 1 1 1 1 1;...

Dear all,
Generally there is always reinforcement curtailment in beam/girder section (i.e fewer main bars in middle part). Here, I want to model those beams in OpenSees, how can I do it correctly? How much would be the error if I modeled it without curtailment?
Thanks in advance..

Hi, I have a question that why multi-support excitation(sine-wave/earthquake wave) has only displacement input? Can we give multi support acceleration input? ( I'm referring to the Wiki examples; http://opensees.berkeley.edu/wiki/index.php/Examples_Manual#Multiple-Support_Sine-Wave). If yes, how can...

Dear all, Here I have a simple model in which I apply the force at one node and wanted to get the moment(=Force * Dist) at the other node but got no results. I use twoNodeLink Element to define the elastic spring and damper. Here I put my coding. Please correct me. for {set n 1} {$n < 5} {incr n} { ...

Dear all,
I've a model which consists of superstructure and foundation. I want to apply the acceleration only for the nodes of the superstructure. How can I do this in OPENSEES?

Dear Vesna,
Thank you very much. I edited the program according to your comments number 3. & 4. and got the expected results.