zerolength element RECORDERS

[Layla]

Hello,

I have a question regarding the recorders of zerolength elements.
For example, I assigned the ElasticPPGap material in a zerolength element and I want the forces and displacements so I used 'force' and 'deformation' recorders. When I open the .out files, the file with the displacements contains 3 data columns (time, u1 and u3) while the force file contains 13 data columns (time and 12 more columns of results). Could you please tell me what are the other 12 columns (F1, F2, F3, R1, R2, R3 ?) ??
Please find below a part of my code.
Thank you very much in advance,
Layla

set matGapx 140;
set Kabx 1;
set Fpoundx -1;
set gapx -0.10;

set matGapy 150;
set Kaby 1; #
set Fpoundy -1; #
set gapy -0.15;


uniaxialMaterial ElasticPPGap $matGapx $Kabx $Fpoundx $gapx; # long direction, gap (no pounding)
uniaxialMaterial ElasticPPGap $matGapy $Kaby $Fpoundy $gapy; # trans direction, gap (no pounding)

element zeroLength 106 1003 1001 -mat $matGapx $matGapy -dir 1 3;

recorder Element -file $THDir/Element106f.out -time -ele 106 force;
recorder Element -file $THDir/Element106d.out -time -ele 106 deformation;

[vesna]

Use -xml recorder option (rather than -file) to get the info on what each column of the output file represents.

[Layla]

Thank you very much for your reply. I used =xml and I took the following but I am still confused.. I mean that the deformations are referred to the whole element while the forces are at each node end? And the order is F1,F2,F3,M1,M2,M3 at start node and F1,F2,F3,M1,M2,M3 at the end node?

Thanks again for your help!
Layla

<OpenSees
xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation = "http://OpenSees.berkeley.edu/xml-schema ... enSees.xsd">
<TimeOutput>
<ResponseType>time</ResponseType>
</TimeOutput>
<ElementOutput eleType="ZeroLength" eleTag="106" node1="1003" node2="1001">
<ResponseType>P1_1</ResponseType>
<ResponseType>P1_2</ResponseType>
<ResponseType>P1_3</ResponseType>
<ResponseType>P1_4</ResponseType>
<ResponseType>P1_5</ResponseType>
<ResponseType>P1_6</ResponseType>
<ResponseType>P2_1</ResponseType>
<ResponseType>P2_2</ResponseType>
<ResponseType>P2_3</ResponseType>
<ResponseType>P2_4</ResponseType>
<ResponseType>P2_5</ResponseType>
<ResponseType>P2_6</ResponseType>
</ElementOutput>
<Data>
0.001 0 0 0 0 0 0 0 0 0 0 0 0
0.002 0 0 0 0 0 0 0 0 0 0 0 0

[vesna]

you got it right.

[Layla]

Thank you very much Vesna for your reply but I am still a little confused..

The fact that there are only 3 displacements and 3 rotations for the zerolenght element and not 12 (6 at each node) does it mean that it responses like a rigid body?
In the case of an elasticPPGap element if all nodes are coincident how does OpenSees understand that the gap is open or close?

Thank you again,
Layla

[vesna]

With deformation recorder you are recording deformations not displacements. If you want to record displacements at the nodes you need to use nodal recorder: http://opensees.berkeley.edu/wiki/index ... e_Recorder