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Hi, skamalzare,

I fixed the issues of shear loading and the time steps. But the model still cannot give me good results. Do you think it is because of the failure of displacementcontrol integrator? If so, how could I make this integrator work? Thanks.

Hi, skamalzare, So glad to see your reply. It is very insightful. I have modified my script as you suggested. It seems the pore water pressure might be ok at the consolidation stage. But the analysis results of the shearing stage still makes no sense if I apply the deviatoric loading as shown below ...

Hi all, I want to simulate a monotonic, consolidated and undrained triaxial compression (CU) test. I am using a single BrickUP element (8-node) and PressureDependentMultiyield02 material. The specimen is a cylinder with the diamter of 50mm and height of 100mm. To make use of the axisymmetry of the s...

Ozgun wrote: > can you try to play with alpha parameter and see if it works? I guess you meant the alpha value for defining SSPquadUP element. I just used the formula given in the manual to compute it as alpha = 0.25*(h^2)/(den*c^2). Maybe I can try to fix the issue by increasing or decreasing the a...

Ozgun wrote: > mhm, > > I think it is not a suggested value. 0.05 is used in the generic examples > but you should use the Poisson's ratio that is valid for the problem you > are working on. otherwise your gravity analysis does not end up with > correct initial state of stress. If I follow your thou...

Ozgun wrote:
> can you try to play with alpha parameter and see if it works?

Hi, Ozgun,

What do you mean by "alpha parameter", could you give more details? I appreciate your help.

Hi, everyone, I tried to use Manzari-Dafalias soil model in a numerical simulation of liquefaction-induced spreading. The numerical model was built in OpenSees, and the Manzari-Dafalias constitutive law was implemented into it as explained here http://opensees.berkeley.edu/wiki/index.php/Manzari_Daf...

Hi, everyone, I am building a shake table model to simulate liquefaction-induced lateral spreading. I need to use so-called "InitialStateAnalysis" wrapper to reset the displacements occurred during the gravity analysis stage to be zero and retain the strains in soil. The model works good without inc...

Hi， I have the same problem with you when I am running my 2D soil model using PressureDependMultiYield material. This is the first time I see this kind of error. It is wired because I have been using same material for other models for quite a while. Did you mention that this error might be caused by...

Hi, TJC, Thanks for your reply. I think you are right. But the problem is I cannot set the dof of slave nodes (i.e. soil nodes) in BeamContact2D elements to be 2 because I would like to capture the pore water pressure change and liquefaction characteristics of soil during shaking. That's why I use q...

Hi, there, I am building a soil model with sheet pile wall in a rigid container of shake table test under earthquake engineering. Basically, I am following the example "excavation supported by cantilevered sheet pile wall". I am not sure about the function of "InitialStateWrapper" and its applicabil...

Hi Dear all, I am building a 2D soil model with 9_4_quadup element and PressureDependYield02 material. I have a problem. During the analysis, these errors come up WARNING: AcceleratedNewton::solveCurrentStep()the LinearSysofEqn failed in solve () NewtonRaphson:: solveCurrentStep() -the Convergence T...

Dear colleague, I would like to know how to impose the Lysmer(fully reflective) BC in OpenSees. I am building a model to simulate the shake table test of liquefiable soil. Basically, I am following the example "Three-dimensional site response analysis of sloping ground" on OpenSees website. The bott...

hi there, I have a huge 3D soil model with 288000 nodes and 303646 elements (SSPbrickUp type). I tried to run it, but in modeling procedure, I received a warning message "Matrix::Matrix : Ran out of memory on init of size 576." I doubted the problem comes from the element type, then I switched to br...