Overestimated peak strength for cube compression. Abaqus/Explicit
Overestimated peak strength for cube compression. Abaqus/Explicit
(OP)
Hi,
I have done compression test for concrete cube using Concrete damaged plasticity model. I assigned BC in Reference point which I coupled with a surf of the cube.
I have got stress-strain curve that looks nice, but Peak strength is 2-3 times higher than it should be.
Ia have uploaded pic of force-displacement.
Can anybody help me?
Thanks
I have done compression test for concrete cube using Concrete damaged plasticity model. I assigned BC in Reference point which I coupled with a surf of the cube.
I have got stress-strain curve that looks nice, but Peak strength is 2-3 times higher than it should be.
Ia have uploaded pic of force-displacement.
Can anybody help me?
Thanks





RE: Overestimated peak strength for cube compression. Abaqus/Explicit
RE: Overestimated peak strength for cube compression. Abaqus/Explicit
Curve is for compression. It is simple uniaxial compression test. There is no Hydrostatic compression state.
I have also checked energy. Allae is small, also kinetic energy is small. So the model should work fine.
If you have some suggesstions I would appreciate it!
RE: Overestimated peak strength for cube compression. Abaqus/Explicit
RE: Overestimated peak strength for cube compression. Abaqus/Explicit
RE: Overestimated peak strength for cube compression. Abaqus/Explicit
This picture I have attached is Force-displacement curve. So, when I divide force of 2.3*10^6 N with Area of 150mmx150mm, I get peak stress of around 100MPa, which is huge!
This is curve for compression for sure, and I am sending you curve for tension.
Also I have just attached sketch with BC from ABAQUS.
RE: Overestimated peak strength for cube compression. Abaqus/Explicit
RE: Overestimated peak strength for cube compression. Abaqus/Explicit
RE: Overestimated peak strength for cube compression. Abaqus/Explicit
Here it is.
I hope you will have some suggestions!
RE: Overestimated peak strength for cube compression. Abaqus/Explicit
- the cross sectional area is 0.2m * 0.2m (not 0.15 * 0.15),
- you have fully restrained all the nodes at the bottom and the top of your model, this has restrained lateral deformation and caused more complicated stress state compared to a pure uniaxial state (poisson's ratio effect),
- you have attempted to apply 25% deformation, which is excessive, but does not make difference apart from skewing your deformation/displacement axis.
- I have tried to put sliding (in plane sliding) BCs to the top and bottom surfaces (providing only a minimum BC to encourage a uniaxial stress state) and the results seem to match better what you would expect.
I will spend some more time over the weekend to look into this.
RE: Overestimated peak strength for cube compression. Abaqus/Explicit
How can I put in plane sliding BC to the top and bottom surfaces? And can you sent me the results you have got?
Thanks for your time and effort!
RE: Overestimated peak strength for cube compression. Abaqus/Explicit
is there any progress?
RE: Overestimated peak strength for cube compression. Abaqus/Explicit
For the top surface, when you tie your reference point to the top surface, you can define which degrees of freedom do you want to tie.
RE: Overestimated peak strength for cube compression. Abaqus/Explicit
Can you send me your CAE file?
Also, have you tried tension test? Just to change the direction of the BC? I have, and it doesnt work well.