Learning Forum

[Oliver Thomsen]

Hi Ansys Forum :)

I would like to begin a discussion with a problem Im currently having.

Not a proffessional in ANSYS WorkBench, so I have based the major commands on discussion in here and from Youtube. I therefore guess this also could be relevant for others in similar position. 

Im modelling a reinforced concrete wall and subjecting it to shear and normal force.

The BC's are based on a wall that in principle can overturn but I regulate the applied loads to not activite this failure mechanism.

The failure mechanism I want to model is the crushing of the corner and tension at the opposite edge. 

However...

I get the wall to deform so that it places all its selfweight on the corner, however no crushing or cracking behavior occur (which from my jugdement should happen). I therefore think that something is wrong with the definition of the material for the SOLID65 (which is based on commands 'stolen' from others.

Is there someone that have had similar problems and then fixed it?

I will just provide some details here:

Concrete C25, Willam Warnke material

ET,MATID,SOLID65
R,MATID,0,0,0,0,0,0
RMORE,0,0,0,0,0

MP,EX,MATID,30575.8555 
MP,PRXY,MATID,0.2
MPTEMP,MATID,0

TB,DENS,1
TBDATA,1,2300

TB,CONCR,MATID,1,9
TBTEMP,22
TBDATA,1,0.3,1,1.8,25

TB,MISO,MATID,1,9,0 
TBTEMP,22
TBPT,,0.000120689655172414,3.69016655770889
TBPT,,0.000241379310344828,6.94085738924437
TBPT,,0.000362068965517241,9.80145314995161
TBPT,,0.000482758620689655,12.3142035252780
TBPT,,0.000603448275862069,14.5154695918616
TBPT,,0.000724137931034483,16.4367151903659
TBPT,,0.000844827586206897,18.1053045400244
TBPT,,0.000965517241379310,19.5451488816296
TBPT,,0.00108620689655172,20.7772344677635
TBPT,,0.00120689655172414,21.8200565467812
TBPT,,0.00132758620689655,22.6899783047455
TBPT,,0.00144827586206897,23.4015294797432
TBPT,,0.00156896551724138,23.9676561554440
TBPT,,0.00168965517241379,24.3999307989400
TBPT,,0.00181034482758621,24.7087297339610
TBPT,,0.00193103448275862,24.9033837914440
TBPT,,0.00205172413793103,24.9923067507723
TBPT,,0.00210000000000000,25
TBPT,,0.00229310344827586,25 !24.8826735443435
TBPT,,0.00241379310344828,25 !24.6972745393916
TBPT,,0.00253448275862069,25 !24.4326108788668
TBPT,,0.00265517241379310,25 !24.0938860155883
TBPT,,0.00277586206896552,25 !23.6858577034653
TBPT,,0.00289655172413793,25 !23.2128847171809
TBPT,,0.00301724137931035,25 !22.6789678157705
TBPT,,0.00313793103448276,25 !22.0877857608253
TBPT,,0.00325862068965517,25 !21.4427270721254
TBPT,,0.00337931034482759,25 !20.7469180978461
TBPT,,0.00350000000000000,25 !20.0032478888722

Reinforcement

ET,MATID,LINK180 
MPDATA,EX,MATID,,2.1e5

MPDATA,PRXY,MATID,,0.3 
TB,BISO,MATID,1,2 
TBDATA,,500,1000
R,MATID,4,,0 

Interaction

/PREP7

ESEL,S,ENAME,,65
ESEL,A,ENAME,,180
ALLSEL,BELOW,ELEM
CEINTF,0.001,
ALLSEL,ALL
/SOLU
OUTRES,ALL,ALL

Cracking/Crushing plots

/SHOW,png

/ANG,1,

/VIEW,1,0,0,0  

SET,1,1

/DEVICE,VECTOR,ON

/POST1

SET,1,, ,,, ,last

PLCRACK,0,0

/POST1

SET,2,, ,,, ,last

PLCRACK,0,0

Boundary conditions

Compression only at y=0
Dis x=0 at y=0

Loads

at y = top

at y = top

 

Have good day!

[peteroznewman]

Hi Oliver,

I am not an expert on cracking/crushing simulation using SOLID65, but I noticed that your solid mesh has only 3 elements through the thickness of the wall.

I suggest you try putting 12 elememt through the thickness and see if that helps.  If you simply make the element size 1/4 of the current size, the number of elements will go up by a factor of 64. If you are using the Student license, that may put the mesh over the limit on the number of nodes or elements of 128,000.  If that is the case, you can sweep 12 elements through the thickness, without changing the default element size.

That will make the element thin in one direction if you don’t change the height. You should also make the bottom layer of elements have the same height as thickness. In Mechanical, you would apply a Mesh Size control on the vertical edges of the wall and use a Bias factor of 4. I'm not sure how you do that in the APDL environment.

[Oliver Thomsen]

Hi Peter

Yes, maybe the problem lies within the definition of the mesh.

Im currently limited by the student license, but I will try to incorporate your ideas.

Thank you, I appreciate the guidance and quick response!