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Hi, I am trying to perform transient analysis with OpenSeesMP on a Lİnux system. OpenSeesMP can generate (load/source) the model but when it comes to analysis operator(or object), it always returns the error below: Error! Unknown CType: -1 mpirun noticed ... on signal 11 (Segmentation fault)." ...

Hi, I have an OpenSees model for a soil deposit including a tunnel in 2D. I used pressure independent material for soil and linear elastic material for frame elements. The model has approximately 10000 nodes which corresponds to 20000 DOFs. I added the following lines to my tcl file to create an app...

Hi, I have read from this forum that the documentation of PressureIndependMultiYield material includes some mistakes and contradictions. Thus, I looked into the source code to correct the documentation and I realized that; when phi (friction angle)>0 shear strength (for deriving yield surfaces) is c...

Dear all, As far as I know, CFL condition must be considered during soil site response modelling in FEM. And this condition is considered and satisfied in OpenSEES site response analysis examples. However, the formula used in this examples is a little different than the original formula for 1D wave ...

selimgunay wrote:
> It is normal as long as the unexpected lateral displacement disappears. Is
> it smaller in the analysis with tolerance of 1e-6?

Yes, it is. The lateral displacements are at level of 1e-13 now (for the tolerance of 1e-6). Thank you for your kind answers.

selimgunay wrote: > 1e-3 is a large tolerance, lateral displacement is likely due tho that. > Which norm are you using? Please try 1e-8 first and then 1e-6 if that does > not work. > > Krylow Newton is supposed to accelerate convergence, 300 is not a very > large number for iterations, depending on ...

Jhno wrote: > No, i don't think it is if you have a simple model. > Did you check example on the OS wiki? They are very well prepared. > > http://opensees.berkeley.edu/wiki/index.php/Site_Response_Analysis_of_a_Layered_Soil_Column_(Total_Stress_Analysis) Yes, I built the model by using these example...

selimgunay wrote: > For the plastic case, it could be due to numerical errors. What is your > convergence tolerance? The convergence tolerance is set to 1e-3, could this cause that problem? By the way, despite the larger tolerance, convergence of Krylov Newton algorithm occurs at nearly 300th iterat...

Jhno wrote: > I use the PIMY material routinely and there is no such problem with it. > I don't understand thought, you say your artifial boundary are fixed in x > direction? There should not be much lateral displacement then. > Maybe start with a very small soil domain and check if this still happe...

Hi, I have modelled a 2D soil deposit with "quad" elements by using "pressure independent multiyield" material. Lateral sides and bottom side of the model are fixed in X direction and Y direction, respectively. The soil domain is modelled to be symmetrical. However, gravity analy...

Hi, I am modelling a soil column to perform 1D site response analysis. I started with the example provided in OpenSEES geotechnical examples and changed the material to elastic isotropic. The problem is, whatever the element size or analysis time step, it cannot converge at some time during the anal...

I think you can define your composite section with partch and fiber commands just like the moment curvature example for reinforced concrete section. I mean, you may define slab with concrete patches and steel fibers (reinforcement) and steel beam with steel patches as a whole.

Rafet

Dear alimohammadian,

The only example you can find is here;

http://opensees.berkeley.edu/community/ ... php?t=5266

Rafet

Thank you Mr. McKenna

At first I did not fix rotational DOFs, but now I have fixed that nodes in both translation and rotation. Now it is working, but I wonder is it appropriate to use truss elements and fix them rotationally?