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Hi, I am modeling 2 retaining structures with soil in between them. If I make the soil mesh in between the walls uniform (i.e. same element size for all elements), the program runs fine. If I make the mesh such that soil element size increases going from the wall to the center line of the soil, I ge...

Well, my main question is: why is the ZeroLengthND material not working even though it is in the manual?
Is there a way to use it?

Thanks.

I am trying to model springs to simulate the interaction between backfill soil and a retaining wall. I want a material that has damping and I will use it with zerolength elements. I wanted to used the same NDmaterial that I am using for the soil backfill. Is that possible? What other options I have?...

Hi,

I am trying to use the zeroLengthND material but I receive an error that the zeroLengthND element is no longer available.

Is there any way where I can use this element? Is there any other equivalent element? Please let me know.

Thanks,
Linda.

Hi Silvia, I have U-shaped retaining structures with soil backfill. When I try to add the mass of the structures as node loads, I get the following message: "Node::addunbalLoad - load to add of incorrect size 2 should be 3" The nodes have ndf 3 and I am using: pattern Plain 1 Linear { load...

Hi Frank/Sylvia, There are problems with some of the commands for the PressureDependMultiYield Material that was developed at UCSD. The "updateParameter" command does not work at all as specified in the manual. The "Backbone" recorder does not work properly. It gives a file outpu...

Hi, I am using the PressureDependentMultiYield material (a UCSD soil model) and I am trying to record the backbone curve as specified in the manual: recorder Element -ele 186 -file Output/soil_dyn_backbone.out -dT $deltaT material 1 backbone $Pref; The recorder is not working. Can anyone help me? Th...

Hi, I am trying to add stiffness proportional viscous damping to my nonlinear MultiYieldPressureDepend soil model using the stiffness at initial state. I have some questions about the way the Rayleigh damping works: Does it treat the whole soil column as one layer and applies one damping value for t...

Hi, I am using the PressureDependMuliYield nDMaterial and I am trying to record the backbone curve for one element as specified in the user manual: recorder Element -ele 36 -file Output/soil_dyn_backbone.out -dT $deltaT material 2 backbone 20000; According to the manual, "In the output file, co...

Hi, I am using the PressureDependMuliYield nDMaterial and I am trying to record the backbone curve for one element as specified in the user manual: recorder Element -ele 36 -file Output/soil_dyn_backbone.out -dT $deltaT material 2 backbone 20000; According to the manual, "In the output file, co...

Hello, I am trying to perform a dynamic analysis on a retaining wall+backfill model. I am interested in recording the moments on the wall and I am using element recorders for that purpose. I am confused about what the recoded moments exactly mean. Are they just the moments on the wall resisting the ...

Hi, I am using the PressureDependentMultiYield material with quad elements in my model for seismic analysis. I already specified the soil mass density in the nDMaterial command. Do I need to specify the mass density also in the quad element command? What is the difference between the material densit...

Hi, I am using the PressureDependMultiYield Material to model DRY medium dense sand. In the User Manual, rho is defined as saturated soil mass density. My question is: do I need to input rho saturated even if my model is dry or for the case of dry sand I should input dry soil mass density for rho? T...

Hi, I am having trouble analyzing my problem. I have a ndm2, ndf2 soil mesh and I am trying to place a beam element on top of the soil simulating a foundation and connecting the beam nodes to the soil nodes by springs. The beam element has ndm2 and ndf3, so I am using dummy nodes to connect the beam...

Thank you Silvia. Just to make sure I understand correctly: So, if node 1 is the fixity, I add another node (node 2) at the same location. I use EqualDOF to constrain node 2 to node 1 in the translational directions. Then, I link node1 and node2 with a zero-length element. I define the uniaxial mate...