moment-curvature

ca493 · Post by **ca493** » Mon Sep 08, 2008 7:29 pm

Hello,

I realized that the Steel01 and Steel02 materials model strength degradation quite nicely (i just made negative isotropic hardening parameters) but i have a question about its application.

I have a zeroLength element that is a rotational spring. I would like to apply the Steel02 material (the one with strength degradation) to represent the momnt-curv relation. It seems OK but is this appropriate considering that the Steel02 material is only for stress-strain (at least i think it is)?

Thank you!

silvia · Post by **silvia** » Mon Sep 08, 2008 7:41 pm

which strength degradation?

yes, you can use it, uniaxialMaterial is a misleading term, they are uniaxial-response objects.

ca493 · Post by **ca493** » Mon Sep 08, 2008 7:56 pm

Thank you once again

I'm trying to capture the cyclic response of a beam with reduced cross section. At each plastic excursion during the cyclic load, the beam's strength is reduced.

Thanks!

ca493 · Post by **ca493** » Mon Sep 08, 2008 10:30 pm

Hello,

I am running into a problem with my model. I cannot seem to record the force and deformation in the spring!

The first column in the recorder output is just the forces calculated by Opensees for the DisplacementControl. The second column (whether it be forces or def) is just zeros.

Here is what I wrote:

Code: Select all

source rotSpring2D.tcl
rotSpring2D 4 1 5 $beam_matID 
recorder Element -file Data/Spring_rot.txt -time -ele 4 deformation
recorder Element -file Data/Spring_Force.txt -time -ele 4 force

I'm pretty sure the zeroLength element is doing its job because when I change the material parameters, the forces in the first column of the recorder outputs change accordingly.

Any suggestions?

Thanks!

silvia · Post by **silvia** » Tue Sep 09, 2008 6:33 pm

if you get zero, not blank, the recorder is doing its job. please check your model.