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Dear all, I was wondering if it is possible to excite a structure built in Opensees, under an excitation angle which doesn't coincide with the global X,Y,Z axes. For example, I would like to excite a 3 story building but I don't want to apply the accelerogram along the X global axis. I would like to...

Hello, I'm trying to simulate a bridge in 3d space. I used fiber section for the pier. In an effort to assign torsional Stiffness for my 3D Model, i used the section Aggregator. Unfortunately,it doesn't seem to work properly. I take the message: ForceBeamColumn 3D:: no torsion detected in sections, ...

Dear all, While analyzing my bridge model (NL time history analysis) I realized that the values of the ultimate curvature at the base of piers are too big (in order of 0.2 1/m). I used fiber section for the piers. I was wondering if the program does calculate the ultimate curvature of the section an...

Thanks vesna!
I downloaded again the 2.3.0 version (the .exe file) and my model still doesn't work. In my computer, if I remove gravity and run the time history, the results are zero.

Dear all, I am trying to do sectional analysis of a column and I would like to know the ultimate curvature of my section. According to these lines of the example provided in http://opensees.berkeley.edu/wiki/index.php/OpenSees_Example_9._Build_%26_Analyze_a_Section_Example # set maximum Curvature: s...

Here is my model! If I replace the mass with lumped masses everything seem to be fine otherwise I have no idea what is happening. Thanks a lot again!! # SET UP ---------------------------------------------------------------------------- wipe; # clear memory of all past model definitions model BasicB...

Thanks a lot for your reply! Yes, I m using the latest version (2.3.0).

Olympia

Dear all, I was wondering about the following: when I do eigenvalue analysis I can define the mass of the model using the -mass property of the forceBeamColumn element but when I do time history analysis cannot do the aforementioned and I need to define the mass of the model using lumped masses (oth...

I mean that if I use the following command:
recorder Node -file nodesD.out -time -node 1 2 3 4 -dof 1 2 disp;
I will take the relative displacements, right?

What if I want to plot the absolute displacements?

Many thanks in advance,
Olympia

Dear all, Is there any other way to take absolute displacements in a time history analysis except for transforming the input motion (which is an accelerogram) to a displacement input motion (I call it ''displ.motion''), run the analysis exciting with the accelerogram and simply add (1) the relative ...

Dear all, I have a simple pier (cantilever beam) and when I do eigenvalue analysis considering elastic section, i take the right results. But when I do eigenvalue analysis using fiber section with same dimensions (d=2.0m) and material Ec=32000000 kPa (of course there are also reinforcing bars), I do...

Thanks a lot Vesna for your reply!! So does it mean that I can excite my structure using as input different accelerograms at different nodes (for example 3 different accelerograms, one at the base of each of the 3 bridge piers, asychronous motion) but the results may not be exact? So it is better to...

Dear all,

I would like to ask if there is an option in OpenSees for multiple support excitation in terms of accerelation input instead of displacements.

Thanks a lot,
Olympia

Dear all, I'm trying to solve a simple 2d problem in which I have modeled a 20m height by 100m length elastic soil domain using quad elements with nDMaterial ElasticIsotropic material. In order to run time history analysis, I excite the base nodes with a= 9.81*sin(2*pi*t) but when I plot the results...

Dear all, It's the first that I use OpenSees in site response analysis.. First of all, I tried to analyze a soil column, I used the input file provided by the website (http://opensees.berkeley.edu/wiki/index.php/Site_Response_Analysis_of_a_Layered_Soil_Column_(Total_Stress_Analysis)) and by doing so...