Elastic Perfectly Plastic Gap Material

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BRYGN
Posts: 4
Joined: Thu Mar 17, 2005 5:34 am

Elastic Perfectly Plastic Gap Material

Post by BRYGN » Fri Apr 08, 2005 10:40 am

I was wondering if there is an input parameter for the ElasticPPGap which will cause it to accumulate damage. In other words. currently as I load it up I get a plastic deformation which is not present during reloading. I know that the manual doesn't show another parameter but I thought I would ask. I was just thinking it would be nice if it could accumulate damage like most other materials do.

Thanks

mackie
Posts: 9
Joined: Mon May 02, 2005 10:53 am

Post by mackie » Mon May 02, 2005 10:55 am

yes, just add the word
damage
to the end of your uniaxialMaterial

it functions as you would expect

silvia
Posts: 3909
Joined: Tue Jan 11, 2005 7:44 am
Location: Degenkolb Engineers
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Post by silvia » Mon May 02, 2005 10:58 am

mackie,
please send me the command information, if there is more, and describe how it accumulates damage.
thank you
Silvia Mazzoni, PhD
Structural Consultant
Degenkolb Engineers
235 Montgomery Street, Suite 500
San Francisco, CA. 94104

mackie
Posts: 9
Joined: Mon May 02, 2005 10:53 am

Post by mackie » Mon May 02, 2005 11:06 am

silvia,

this is the current syntax:

uniaxialMaterial Elastic ElasticPPGap $matTag $E $Fy $gap <damage>

but Frank is sitting on a new version that has kinematic hardening built in, so the syntax in a day or so will then become:

uniaxialMaterial Elastic ElasticPPGap $matTag $E $Fy $gap <damage> <eta?>

where eta is Eh/E (ratio of hardening to elastic stiffness)

Kevin

mackie
Posts: 9
Joined: Mon May 02, 2005 10:53 am

Post by mackie » Mon May 02, 2005 11:10 am

errr, sorry, the eta comes before the damage in the new version, but can be omitted so that the previous syntax is still valid.

ie, the old way works:
uniaxialMaterial Elastic ElasticPPGap $matTag $E $Fy $gap <damage>

and the new way is:
uniaxialMaterial Elastic ElasticPPGap $matTag $E $Fy $gap <eta?> <damage>

silvia
Posts: 3909
Joined: Tue Jan 11, 2005 7:44 am
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Post by silvia » Mon May 02, 2005 11:20 am

super, thank you.
Silvia Mazzoni, PhD
Structural Consultant
Degenkolb Engineers
235 Montgomery Street, Suite 500
San Francisco, CA. 94104

mackie
Posts: 9
Joined: Mon May 02, 2005 10:53 am

Post by mackie » Mon May 02, 2005 11:22 am

ok, while I'm continually making some more errors, I just noticed it says Elastic ElasticPPGap, which is of course not true, it's just ElasticPPGap :)

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