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calculix / CalculiX-Examples

CalculiX examples by Prof. Martin Kraska from Brandenburg University of Applied Sciences. Excellent starting point to master parametric modelling with CGX and CCX.
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Modelling different elasto-plastic behaviour in tension and compression #52

Open alda30 opened 3 years ago

alda30 commented 3 years ago

Hi,

I'm trying to model a fibre reinforced concrete beam with different stiffness and stress-strain curve in tension and compression. How should I implement this model? Can I simply add the compression with negative values as below: (example numbers) *plastic -1200,-1 -100,-0.1 20,0.1 120,1

Thanks in advance for your help and assistance.

Alex

mkraska commented 3 years ago

I don't think that this approach will work, because the stress-strain curve is defined in terms of equivalent stress and equivalent strain, which both can't be negative.

mkraska commented 2 years ago

Theoretically, a non-symmetric stress-strain curve (yield curve) could be obtained by using kinematic hardening with non-zero initial back stress. This, however, would not affect stiffness.

mkraska commented 2 years ago

How about a combination of compression-only and linear elastic material? Essentially, you copy each element and assign the second material to the copies.