Soil Contact Issue

classic Classic list List threaded Threaded
3 messages Options
Reply | Threaded
Open this post in threaded view
|

Soil Contact Issue

Froido
Hi,
 I am currently working on a model to simulate the compaction of geological reservoirs during the extraction of pore water. Since the model will be a few kilometers long, I would like to first look at the necessary mechanisms in a small 2-D model (standard).
 

 Here I have a problem with the contact of two soil parts. Since general contact cannot be used with 2-D, I created a surface-surface-contact between the two surfaces: Small sliding; No adjustment; Friction Coeff 0.8; Normal Behavior (default).
 Unfortunately the Geostatic-Step is aborted immediately (Too many attempts made for this increment). I have tried in several ways to establish the contact, but have remained unsuccessful.
 

 The goal is to compress one of the two parts by a few centimeters, while the other part only reacts to the movement, but is not loaded directly.
 

 Under the following link you can find the input file:
 https://rwth-aachen.sciebo.de/s/3A67pzolJIOFq5c
 

 I'm looking forward to good advice and thank you in advance.
 Many greetings
 Sven
Reply | Threaded
Open this post in threaded view
|

Re: Soil Contact Issue

George Papazafeiropoulos
Hello Sven,
 

 Replace the lines 17870-17872 in the input file Job_08.inp with the following:
 

 *Step, name=Step_Geostatic, nlgeom=NO, inc=100000
*Geostatic, utol
0.01, 1., 1e-07, 1.

Actually, this replacement reduces the time step size by 100 and increases the number of maximum increments. In addition, replace the line 17864 in the input file Job_08.inp with the following:
 

 *Contact Pair, interaction=IntPropFric08, small sliding, type=SURFACE TO SURFACE, adjust=0.01


 I have run the Abaqus input file with these modifications and the results are below:
 

 https://ufile.io/aeu26 https://ufile.io/aeu26

 https://ufile.io/aeu26

 Best regards,
 

 _______________________________________________
George Papazafeiropoulos
Captain, Infrastructure Engineer, Hellenic Air Force
Civil Engineer, M.Sc., Ph.D. candidate, NTUA
Email: [hidden email]

 

Reply | Threaded
Open this post in threaded view
|

Re: Soil Contact Issue

Fureto San
In reply to this post by Froido
Hello Sven,

Greetings from Brazil. I've been doing simulations with contact conditions,
and this has quickly lead me to drop Standard simulations, because of
convergence difficulties, and preferred and
Explicit formulation. Implicit simulations have many restrictions (contact,
convergence), as do Explicit simulations (correctness, cost). In any case,
your .inp file contains a few thousand elements, which might be quick if
run under explicit (don't forget to change element types). Also, even if
your actual volume spans kilometers, you might be able to escape excess
model complexity by adjusting dimensions and units.

Have a good one!
Fred

On Sat, Dec 15, 2018 at 6:05 PM [hidden email] [Abaqus] <
[hidden email]> wrote:

>
>
> Hi,
>
> I am currently working on a model to simulate the compaction of geological
> reservoirs during the extraction of pore water. Since the model will be a
> few kilometers long, I would like to first look at the necessary mechanisms
> in a small 2-D model (standard).
>
>
> Here I have a problem with the contact of two soil parts. Since general
> contact cannot be used with 2-D, I created a surface-surface-contact
> between the two surfaces: Small sliding; No adjustment; Friction Coeff 0.8;
> Normal Behavior (default).
>
> Unfortunately the Geostatic-Step is aborted immediately (Too many attempts
> made for this increment). I have tried in several ways to establish the
> contact, but have remained unsuccessful.
>
>
> The goal is to compress one of the two parts by a few centimeters, while
> the other part only reacts to the movement, but is not loaded directly.
>
>
> Under the following link you can find the input file:
>
> https://rwth-aachen.sciebo.de/s/3A67pzolJIOFq5c
>
>
> I'm looking forward to good advice and thank you in advance.
>
> Many greetings
>
> Sven
>
>
>


--
Att,
Fred