Zero length spring element with equal stiffness in all dir?

kishor · Post by **kishor** » Thu Feb 19, 2009 12:42 pm

Dear Dr. Silvia and all

How to develope or have zero length spring element having equal axial stiffness in all directions?

silvia · Post by **silvia** » Thu Feb 19, 2009 12:45 pm

assign the same material to all springs, one in each direction.

kishor · Post by **kishor** » Thu Feb 19, 2009 1:10 pm

Does the capacity (strength and stiffness) of a joint increase if we define same string in each direction? I mean like resultant which I do not want.

From you suggestion I think they will work separately. Please clear me!

Thank you!

silvia · Post by **silvia** » Thu Feb 19, 2009 1:11 pm

not sure....

kishor · Post by **kishor** » Thu Feb 19, 2009 1:59 pm

Is there any way to check this ?

Thank you

silvia · Post by **silvia** » Thu Feb 19, 2009 2:05 pm

yes, try it with a simple model.

it may be hard, though.

what about the zerolengthND model?

kishor · Post by **kishor** » Thu Feb 19, 2009 2:25 pm

Thank you for your patient!

We have test data of connection for cyclic load in axial direction. I did a model with a zero length element which can represent very well with the test data.

Now I need to integrate this model with a overhall shell model of diaphragm and connect with shell elements. I need to connect in X and Y directions. So if I used the calibrated spring element in both direction, I do not know, am I increasing the connection strength or stiffness ?
If so how can I model this ?

Thank you again!

silvia · Post by **silvia** » Thu Feb 19, 2009 7:25 pm

you know, maybe some sort of fiber section with a circular section -- that should work.

kishor · Post by **kishor** » Fri Feb 20, 2009 8:28 am

Thank you!
I checked the possibility of using fiber section but I could not get idea how to use it for my purpose as it seems basically for RCC beam or column sections

silvia · Post by **silvia** » Fri Feb 20, 2009 8:30 am

sure,
but you want an elastic section, right? so just use elastic material, one single circular patch -- and calibrate it to the stiffness you want.

kishor · Post by **kishor** » Fri Feb 20, 2009 8:42 am

Thanks,
No I want the inelastic response (force verses deformation) of steel deck roof diaphragm connections. The connections are nails and screws.

silvia · Post by **silvia** » Fri Feb 20, 2009 9:20 am

play around with a nonlinear material, then.

boyaci · Post by **boyaci** » Fri Dec 30, 2011 12:07 pm

Thanks to you a little bit informed. the site thank you very much. Have a good day

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Zero length spring element with equal stiffness in all dir?

Zero length spring element with equal stiffness in all dir?

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