Recorder in zeroLenght element

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alirezaii
Posts: 37
Joined: Fri Mar 16, 2012 8:07 am

Recorder in zeroLenght element

Post by alirezaii »

Hello vesna
I have a problem with the 'stressANDstrain' recorder in rotational spring.
A piece of my code is:
###########################################################################################################
# rotPanelZone2D.tcl
# Procedure that creates a rotational spring and constrains the corner nodes of a panel zone
#
# The equations and process are based on: Krawinkler Model for Panel Zones
# Reference: Gupta, A., and Krawinkler, H. (1999). "Seismic Demands for Performance Evaluation of Steel Moment Resisting Frame Structures,"
# Technical Report 132, The John A. Blume Earthquake Engineering Research Center, Department of Civil Engineering, Stanford University, Stanford, CA.
#
#
# Written by: Dimitrios Lignos
# Date: 11/09/2008
#
# Formal arguments
# eleID - unique element ID for this zero length rotational spring
# nodeR - node ID which will be retained by the multi-point constraint
# nodeC - node ID which will be constrained by the multi-point constraint
# E - modulus of elasticity
# Fy - yield strength
# dc - column depth
# bf_c - column flange width
# tf_c - column flange thickness
# tp - panel zone thickness
# db - beam depth
# Ry - expected value for yield strength --> Typical value is 1.2
# as - assumed strain hardening
##########################################################################################################

proc rotPanelZone2D {eleID nodeR nodeC E Fy dc bf_c tf_c tp db Ry as} {

# Trilinear Spring
# Yield Shear
set Vy [expr 0.55 * $Fy * $dc * $tp];
# Shear Modulus
set G [expr $E/(2.0 * (1.0 + 0.30))]
# Elastic Stiffness
set Ke [expr 0.95 * $G * $tp * $dc];
# Plastic Stiffness
set Kp [expr 0.95 * $G * $bf_c * ($tf_c * $tf_c) / $db];

# Define Trilinear Equivalent Rotational Spring
# Yield point for Trilinear Spring at gamma1_y
set gamma1_y [expr $Vy/$Ke]; set M1y [expr $gamma1_y * ($Ke * $db)];
# Second Point for Trilinear Spring at 4 * gamma1_y
set gamma2_y [expr 4.0 * $gamma1_y]; set M2y [expr $M1y + ($Kp * $db) * ($gamma2_y - $gamma1_y)];
# Third Point for Trilinear Spring at 100 * gamma1_y
set gamma3_y [expr 100.0 * $gamma1_y]; set M3y [expr $M2y + ($as * $Ke * $db) * ($gamma3_y - $gamma2_y)];


# Hysteretic Material without pinching and damage (same mat ID as Ele ID)
uniaxialMaterial Hysteretic $eleID $M1y $gamma1_y $M2y $gamma2_y $M3y $gamma3_y [expr -$M1y] [expr -$gamma1_y] [expr -$M2y] [expr -$gamma2_y] [expr -$M3y] [expr -$gamma3_y] 1 1 0.0 0.0 0.0

element zeroLength $eleID $nodeR $nodeC -mat $eleID -dir 6

equalDOF $nodeR $nodeC 1 2
# Constrain the translational DOF with a multi-point constraint
# Left Top Corner of PZ
set nodeR_1 [expr $nodeR - 2];
set nodeR_2 [expr $nodeR_1 + 1];
# Right Bottom Corner of PZ
set nodeR_6 [expr $nodeR + 3];
set nodeR_7 [expr $nodeR_6 + 1];
# Left Bottom Corner of PZ
set nodeL_8 [expr $nodeR + 5];
set nodeL_9 [expr $nodeL_8 + 1];
# retained constrained DOF_1 DOF_2
equalDOF $nodeR_1 $nodeR_2 1 2
equalDOF $nodeR_6 $nodeR_7 1 2
equalDOF $nodeL_8 $nodeL_9 1 2
}



rotPanelZone2D 42300 2303 2304 $Es $Fy $dcol_12 $bfcol_12 $tfcol_12 $twcol_12 $dbeam_23 $Ry $as_PZ;

and recorder is:

recorder Element -file "$OutFileID/20smfp_Output/panelzone/stressANDstrain/rezajoon1.txt" -time -ele 42300 stressANDstrain

recorder Element -file "$OutFileID/20smfp_Output/panelzone/stiffness/rezajoon2.txt" -time -ele 42300 stiffness

Also I try :
recorder Element -file "$OutFileID/20smfp_Output/panelzone/stressANDstrain/rezajoon1.txt" -time -ele 42300 material 42300 stressANDstrain

recorder Element -file "$OutFileID/20smfp_Output/panelzone/stiffness/rezajoon2.txt" -time -ele 42300 material 42300 stiffness

But I couldn't get the StressStrain response of system!

please help me
Best Regards
vesna
Posts: 3033
Joined: Tue May 23, 2006 11:23 am
Location: UC Berkeley

Re: Recorder in zeroLenght element

Post by vesna »

The recording arguments of zeroLenght element are: 'force,' 'deformation,' 'stiff,' and 'material $matNum matArg' Where $matNum is the tag associated with the material whose data is to be output. The recording arguments of hysteretic material are: 'strain,' 'stress,' and 'tangent'. None of the recorders you specified is not correct.

Other than that, your rotation spring is defined by moment-rotation relationship and therefore you can not record stresses.
alirezaii
Posts: 37
Joined: Fri Mar 16, 2012 8:07 am

Re: Recorder in zeroLenght element

Post by alirezaii »

Dear vesna
Thanks a lot for your reply.
I try :
recorder Element -file "$OutFileID/20smfp_Output/rezatangent.txt" -time -ele 42300 material 42300 tangent
recorder Element -file "$OutFileID/20smfp_Output/rezastiff.txt" -time -ele 42300 stiff
recorder Element -file "$OutFileID/20smfp_Output/rezastrain.txt" -time -ele 42300 material 42300 strain
recorder Element -file "$OutFileID/20smfp_Output/rezastress.txt" -time -ele 42300 material 42300 stress

But these recorders diden't record any result in output.
vesna
Posts: 3033
Joined: Tue May 23, 2006 11:23 am
Location: UC Berkeley

Re: Recorder in zeroLenght element

Post by vesna »

The arguments of the recorders look good. Can you try with a simple file name (e.g., rezatangent.txt)?
alirezaii
Posts: 37
Joined: Fri Mar 16, 2012 8:07 am

Re: Recorder in zeroLenght element

Post by alirezaii »

Hello vesna
I try also this recorder, and only time is recorded in output.

Another problem is the track of moment and rotation in beams and columns individually at the location of beam-column connections. I have a simple beam-column connection and want to get the rotation and moment of beam and columns at the start of the clear distance of span.

also I have a problem with "deformation" output. I see that this recorder record three value for any element in output. But I don't know they refer to what!

Thanks in advance
vesna
Posts: 3033
Joined: Tue May 23, 2006 11:23 am
Location: UC Berkeley

Re: Recorder in zeroLenght element

Post by vesna »

If the only output you get is time your output command is wrong. Check the tag of element and tag of material.

To see what the outputs refer to save the data using -xml option rather than -file option.
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