Hi, sorry for the abrupt end yesterday.
There is the rest:
R33=square root [(r90.(r0+1))/(r0+r90)],
finally R12=square root[(3.(r0+1).r90))/(2.r45+1).(r0+r90)]
Assuming that your r-values has been derived from a simple tensile test.
I forgot to mention that the above data were derived for thin...
I am not that experienced however I have faced similar problems half a year ago. The coefficients Rxx, Ryy, Rxy etc. are ratios of measured yield stress to the reference yield stress and represent application of Hill's potential function into abq code without need to use UMAT.
You can calculate...
Thank you very much for your support.
Recent progress is actually good.
I have very small arch that is very sensitive to geometry changes.
But the main point turned out to be the damping coefficient and to choose a proper loading level. I have too much carefully used smaller displacement then...
Thank you very much for your advices.
finally I went step-by -step through the example in the ABQ example manual. And now I am fiddling with damping coefficients in static analysis instead of using riks.
The punch is now analytical rigid.
The edge of the dome is pinned.
I will post my progress...
And yet one more question: The material is stainless steel and I have both the elastic and plastic data. For the buckling analysis though only the elastic properties are necessary, is that right?
I could not get the "snap" for this material even for the 2D analysis as in the example manual...
However the snap-through analysis works well for 2D plates, I can not get it. I have even tried the MAX1 elements and modeled the dome as a membrane, still nothing.
Hello Martin,
thank you for your advice.
I think, I am doing some non-sense. I do need to get the punch force but even when getting RF from the punch reference node still the results are not good. I am still a beginner with ABQ so my questions are probably stupid enough, I am sorry.
NLGEOM are...
It seems that I may be able find the solution after some more research and trying. I have used now the riks analysis for the buckling and the model seems to work OK. Now the main problem is to get the force output. I am still confused about it.
I would welcome your kind consideration.
The model looks like half lens (deformable shell) with punch (rigid) above it. I tried to apply both force and displacement every time with similar results. I am out of any ideas. Please, anyone, help!
Hello,
I have modeled axisymmetric analysis of sheet dome (simple push button).
I need to get the force response of the sheet metal. According to experimental results the force increases until certain level then the "spring" action occurs and the force drops a little bit and if you keep "pushing...
Thank you all for your kind advices.
the elements are CAX4R - axisymetric stress elements. I am imposing displacement in the U1 direction , the nodes on the revolution axis are fixed in U1 and UR3 direction, can freely move along the axis of symetry. Still experiencing the same problem, after...
2harry 123456: the analysis does not abort at all, it completes successfully, the results are what worries me as they are not realistic.
The elastic material with little friction is better but after larger deformation (comparing to elasto-plastic one) it penetrates again. When using...
Hi, thank you all for the answers.
2psantunes: Yes, the deformable body penetrates the rigit near the revolution axis but it might be as well misleading as there really is a highest deformation in the direction of rigid body.
2harry123456: I will try and I will get back here.
I forgot to add some details of the analysis, I am using ABQ 6.4, the contact is established in Initial step before applying load, the load used is actually displacement. The elements are axisymmetric 8 nodded hexahedral elements. I realy hope someone can help me.
Thank you in advance.
Hello, I am a newbie to ABQ, so please have patience with me :-).
I am modeling contact analysis between rigid and deformable (elasto-plastic steel) body. The problem is axisymetric, the rigid body is wire. The interface is free interface (I used tangential frictionless behavior). When applying...