3D rigid diaphragm

[sualim]

hi

my model is 3D RC model

and I used zerolength commend at the end of element

to effect slab, I used rigidDiaphragm commend

but the analysis time was too long

I think rigidDiaphragm commend was not good for the lumped plasticity model

so I used the truss
(section Elastic 1 2e11 2e11 2e11 2e11 2e11 1e-8
element truss 201301 201002 202001 1)

is it right? or using another element will be better? (like uniaxialMaterial concrete ...-> element truss...)

plz give me some comment thank you

[fmk]

you are doing the same thing by adding trusses and using a Penalty method to enforce constraints .. the only issue you may have is numerical due to large values of the stiffness terms .. they only need to be 1000 times greater than the stiffnesses of other elements to get constraint you want withing region .. too large you get numerical roundoff issues which can makes results gibberish.