I’m trying to calculate the natural frequencies and the modes of vibrations, during the execution it stops and the message “out of memory in 3DEC” appears.
Do you know how I can solve this problem?
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3DEC doesn’t dynamically allocate memory. So you need to tell it how much memory your model will use before you run the model. Go to Tools - Options - Configuration - and increase the Main Array Size. This is the memory in MB. So if you enter 6000 then you are setting aside 6 GB of memory for 3DEC.
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It seems that 3DEC has memory limit for the Main Array Size. Is it possible to override it or extract global stiffness matrix (via Fish) and use it with other eigensolver. We have DEM model of the cathedral with deformable blocks and for vertical loading and earthquake records works just fine.
Is the problem that the 3DEC doesn’t work? Or it runs out of memory? (see above for how to increase the memory). Or is it too slow? Right now you can’t export the matrix, but we could add a command to do that.
On my machine 3DEC allocates approximately max 250 GB of memory, even if you ask more, let’s say 500 GB (500 000 Mb). It is a bit slow process, yes, but acceptable. The problem is that I need more then 250 GB and 3DEC runs out of memory, even with this 250 GB. I have 1.8TB of SSD disk space available. Model is really good (see screenshoot) but we need eigenvalues/vectors to compare them with the results of the operational modal analysis on the building, for calibration purposes of course. There are other ways to estimate fundamental period, using the Rayleigh quotient or initial velocity impulse, even earthquake record on the elastic structure, but it would be great to find eigensoluton for this model.
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Oh wow. Probably we need to implement a more sophisticated solver that uses sparse matrices. In the short term, if 3DEC is running out of memory, there is not much you can do. If you want to send the model to tech support we can look at it.
It is greyed out when the model is running. You can’t change the memory while it is running.
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