Can "*Debond" do the 3D crack propagation ?

[cabbin]

Hi,

I used "*Debond" and "*Fracture criterion" for studing the crack propagation.

the 2D model has well passed. but not for 3D model. Abaqus indicate theses two errors :

*surface behavior,augmented lagrange keyword cannot be used if *initial condition,type=contact is specified

The *debond keyword is only valid for planar or axisymmetric contact surfaces. Slave surface assembly_surf_slave is not of this type


can't *Debond really treat 3D crack propagation ?

I have ever seen some examples of 3D crack propagation in Abaqus, How can they do it ?

 

[xerf]

From ABAQUS documentation (ABAQUS Analysis User's Manual v6.6->11.4.3 Crack propagation analysis):

"Crack propagation analysis:

-models quasi-static crack growth in two dimensions (planar and axisymmetric);"

I think you can model crack propagation in 3D using cohesive elements instead of debonding.

Also, you might be interested in Zencrack:

http://www.zentech.co.uk/zencrack.htm

 

[albert1981]

Hallo everybody,

I would like to simulate a crack growth. Is it possible to make an analysis where the load applied and the crack (as nodes release) are in function of time?

Thanks in advance,
Albert

 

[cabbin]

thanks very much, xerf !

by the way,
In the keywords of "*fracture criterion", there are these phrases :

Data lines to define the critical stress criterion (TYPE=CRITICAL STRESS):
First line:
1. Normal failure stress, x1.
2. Shear failure stress, y1.
3. Shear failure stress, y2. (Not applicable in two dimensions.)

if *Debond can't do 3D, in "*fracture criterion", why there are still a "y2" which seems to be applied for 3D ?

 

[xerf]

Sometimes ABAQUS documentation is a little mysterious.

I have not tried it, but I think the procedure might work if the surfaces to be debonded are planar (in 3D). Then, the documentation and the error message you got would make more sense.