Make large displacements to see damage model in UDEC 6

In my case i have a slope model with many joints. I applied load and want to check the slip and breakage between joints. But the problem shows low stiffness of joint. When I increase the stiffness, the fractures and breakage reduces, the model gets too strong. But I need to check large displacements. Can anyone tell me how to remove overlapping of blocks between contacts. I want to see more displacements between the blocks. Please help me solve the problem. Thank you.

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The forces between blocks are calculated by the amount of penetration of one block to another. If the joint normal stiffness is too small, the blocks will penetrate too far and the blocks may pop through each other. If the stiffness is too high, the time step will be lowered and the model will take longer to run. It is best to use a measured joint normal stiffness. Often this is not available. In this case a good number would be two orders of magnitude larger that the rock bulk modulus. For slopes, sometimes even lower values may work.
I do not understand why changing the stiffness affects the failure of contacts. The contact strength is a function of the friction, tension, and cohesion properties (not the stiffness).

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Hi, I didn’t find a button to post my problem, so just ask some after your reply:). Is udec.shutdown() in Itasca-API for python working? Beacause I got a errorWarning as there was no attributes to kill the UDEC .And how can I set a memory by command for UDEC, specifically for udeconsole700.exe? Thanks in adavance!! Xiang

UDEC 7 does not have a Python interface.
The command:
block config array v
will set the startup memory for UDEC. It remains in effect until it is changed by a new command. You need to restart for it to take effect. V is in MBytes.

That’s working! Thanks for your suggestions:)

I suggest creating a simplified version of your model and use that to understand the effects of the various input parameters on the slope behavior.

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@udecsupport Thank you for the suggestions