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Is the 3rd DOF constrained in at least one node (e.g. surface nodes should have 0 pore pressure)?

I think OpenSees is perfectly capable of doing both static and dynamic analyses and should be use for both. Analytically, there should be the capability of using Mohr Coulomb, Modified Cam Clay ,and the hardening soil model (very common in plaxis). The first two exist but their implementation inside...

Is there a way to find cumulatively all the changes between distributions? Or give dates and compare all the files that changed between them?

Thanks!

Not a problem, just use the up elements (2D or 3D depending on your problem).

which version of OS are you using? if you go to the ucsd opensees site they have examples illustrating the use of the updatematerials command (e.g. cyclic.ucsd.edu/opensees/soil2/soil2.txt) if they do not work then there might be a problem with your version. this command works fine with my version I...

how do you initialize your stress conditions? do you match elastic poissons ratio with K0 and then check to see if the stresses of the elastic step are correct? If you are having problems with stiffness constrast you can choose any stiffness you want to get your elastic initial stresses right and th...

Is there any use that when the test increment (energy, displ, force) becomes INF or NAN the analysis object does not return a failed analysis?

At least in my analyses (geotechnical eaqrthquake engineering) it is confusing and time-consuming.

Hi,

I remember some years ago it wasn't right to use transformation handler if you have objects that tie to other objects, that tie to other objets.
(e.g.
equalDOF 1 2 1 2
equalDOF 2 3 1 2
)

Is it still a problem? Do we still need to use penalty handlers for this type of problem?

Antonios

Hi all, I am using MultipleSupport to apply some boundary pore pressure boundary conditions. The problem is that, in my model, if the imposed motion objects are more than 85 then opensees will stop. (i will get a windows error message - no output concerning problems in my model) I've tried putting i...

For the UC San Diego Soil Elements > FourNodeQuadUP elements I haven't tried it on the other three UCSD soil Elements but since for all the four elements the velocity of the third DOF is the pore pressure then it should work for all four. To set pore pressure to be $p at node $NodeID then one should...

> in the recorder specify the option to choose a recording timestep: -dT $dt > Specify that the zerolength elements can only connect 2DOF nodes. > indicate how to remove recorders (e.g. set a [recorder $arguments] remove a ) > Also discuss removing fixities. >Indicate that the model basicbuilder com...

Check this out:

web.mit.edu/avytin/www/site_files/Microsoft%20Word%20-%20Manual%20Centrifuge.pdf

What is the reaction recorder recording in a node that is tied with another one with equalDOF objects? Is it correct to use it to get the internal forces between the two nodes?

try something like that:

# Creating a recorder:
set r_1 [recorder Node -file output_disp_31.txt -nodeRange 1 4204 -time -dT 1. -dof 1 2 disp]

# destroying the recorder:
remove recorder $r_1

yes