Bouc-wen model and ZeroLength Element

[Gholamreza]

Hello Engineers,
I was wondering if we can assign Bouc-wen material to ZeroLength elements???? I tried but it seems the Bouc-wen material is ignored!!
I use the following:

(node#1)..........Elastic Material...............(node#2)Bouc-wen material(node#3)

nodes #2 and #3 are connected with a ZeroLength element but the Bouc-wen material is ignored.

[selimgunay]

You need to define the Bouc-wen material as a unizxialmaterial and assign it to your zerolength element

https://opensees.berkeley.edu/wiki/inde ... n_Material
https://opensees.berkeley.edu/wiki/inde ... th_Element

[Gholamreza]

Thanks for your prompt response. I already did that. I connect nodes#1 and #2 by elastic material and nodes #2 and 3 by bouc-wen material assigned to zeroLength element. here is the related part of the code:

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

fix 1 1 1 1;
fix 2 0 1 1;
fix 3 0 1 1;

#Define Bouc-Wen Material
uniaxialMaterial BoucWen $matTag $alpha $ko $n $gamma $beta $Ao $deltaA $deltaNu $deltaEta

# columns
element elasticBeamColumn 1 1 2 $Ac $E $Ic $TransfTag;
element zeroLength 2 2 3 -mat $matTag -dir 1
########################################################################################################################

The problem is no matter what values I select for Bouc-Wen material arguments, the response does not change? that's why I thought maybe the material is ignored when it is assigned to ZeroLength element.

[selimgunay]

The results should change I think. Could you try replacing the Bouc-Wen with an elastic material and see if the results change when you change the parameters?