Support for a new damper

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Gholamreza
Posts: 84
Joined: Tue Nov 07, 2017 7:47 am
Location: University of Central Florida

Support for a new damper

Post by Gholamreza » Wed Feb 10, 2021 7:46 am

Hello everyone,

I have developed a new material(C++) for a new damper to implement in OpenSees. The new damper does not have stiffness, like a dashpot, and I need to have a chevron frame as support to mount the damper but instead of chevron frame I modeled a very rigid link....... Is this the right way to model the support for such a damper, dashpot, in OpenSees.Please see the related part of a code below (chevron frame as a support of the damper, is modeled as a very rigid link):

########################################################################################################################

model BasicBuilder -ndm 2 -ndf 3

#NODES
node 1 [expr 4.0*0.0] [expr 3.0*0.0];
node 2 [expr 4.0*1.0] [expr 3.0*0.0];
node 3 [expr 4.0*0.0] [expr 3.0*1.0];
node 4 [expr 4.0*1.0] [expr 3.0*1.0];

#DAMPER
node 5 [expr 4.0*0.5] [expr 3.0*0.0];
node 6 [expr 4.0*0.5] [expr 3.0*1.0];
node 7 [expr 4.0*0.5] [expr 3.0*1.0];

fix 1 1 1 1;
fix 2 1 1 1;
#DAMPER
fix 5 1 1 1;
.
.
.
# columns
element elasticBeamColumn 1 1 3 $Ac $E $Ic $TransfTag;
element elasticBeamColumn 2 2 4 $Ac $E $Ic $TransfTag;

# beams
element elasticBeamColumn 3 3 7 $Ab $E $Ib $TransfTag;
element elasticBeamColumn 4 7 4 $Ab $E $Ib $TransfTag;


#DAMPER
#uniaxialMaterial Elastic $matTag $E <$eta> <$Eneg>
set matTag_Estiff 100
set Estiff [expr 200e+7]
uniaxialMaterial Elastic $matTag_Estiff $Estiff

element twoNodeLink 5 5 6 -mat $matTag_Estiff $matTag_Estiff $matTag_Estiff -dir 1 2 3;
element zeroLength 6 6 7 -mat $matTag_SD -dir 1;
.
.
.
########################################################################################################################

selimgunay
Posts: 879
Joined: Mon Sep 09, 2013 8:50 pm
Location: University of California, Berkeley

Re: Support for a new damper

Post by selimgunay » Mon Feb 15, 2021 12:36 pm

I could not find where $matTag_SD was defined in your script.

Gholamreza
Posts: 84
Joined: Tue Nov 07, 2017 7:47 am
Location: University of Central Florida

Re: Support for a new damper

Post by Gholamreza » Mon Feb 15, 2021 3:28 pm

$matTag_SD is my new material I developed in c++. My question is about the support of this damper! In the aim of simplicity, let say we use dashpot or Viscous material, uniaxialMaterial Viscous, instead of $matTag_SD......my question is if the way I use to mount the new damper/dashpot is correct?
I used a very stiff elastic material and twoNodeLink element to make a support (a chevron frame) to mount my new material/dashpot between floors. Is it the right way to do so ?

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