Error while using Null model in 3DEC

3DEC
1

We are simulating the cut and fill in a tunnel. However when we use the cmodel as null the error is being displayed as below.

block zone cmodel assign null range group ‘005’ or ‘018’ or ‘020’
*** Model null not supported. Use BLOCK EXCAVATE

block zone cmodel assign ?
Expected tokens:
Keywords: anisotropic burgers burgers-mohr columnar-basalt
concrete double-yield drucker-prager elastic
hoek-brown imass maxwell modified-cam-clay
mohr-coulomb mohr-coulomb-tension null orthotropic
power power-mohr softening-ubiquitous
strain-softening ubiquitous-anisotropic
ubiquitous-joint von-mises wipp wipp-drucker
wipp-salt
block zone cmodel assign null ?
*** Model null not supported. Use BLOCK EXCAVATE
While processing line 3 of source GUI Console.

When we use the block excavate and run for factor-of-safety, it is reporting error that some zones has no constitutive model assigned.
If we try to use block zone cmodel null then it suggests for using block excavate.

1 Like
2

The error message says it all. In 3DEC, model null is not supported and you need to use BLOCK EXCAVATE.

In theory, the excavated blocks should obtain constitutive models from adjacent blocks, so that error is a bit puzzling. To make sure it works, you can assign a constitutive model and properties to the blocks before excavating. If you want to send the model to 3decsupport@itascacg.com we can look at it.

Of course, if you are not planning to backfill, you can just use BLOCK DELETE instead.

3

Thanks for your reply I have sent the data file for a simple model where the error reported earlier is demonstrated. Please look in to the problem and suggest.

4

OK - we fixed this. The problem was with running a factor of safety analysis with excavated blocks. The fix will be in the next v9 update.

1 Like
5

Thanks for fixing the error.

6

Hi, I’m experiencing a similar problem running the factor of safety analysis with excavated zones in FLAC2D. Can you help me?