no torsion specified for 3D fiber section

[gookki]

I was learning coding now while dealing with example problems.

https://opensees.berkeley.edu/wiki/ind ... W-Section
Therefore, I tried to debug by taking the example problem from the above training site and running it as it is.
However, I encountered the following error.

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WARNING - no torsion specified for 3D fiber section, use -GJ or -torsion

FiberSection3d: 4

while executing
"section fiberSec $secID {
# nfIJ nfJK yI zI yJ zJ yK zK yL zL
patch quadr $matID $nfbf $nftf $y1 ..."
(procedure "Wsection" line 32)
invoked from within
"Wsection $ColSecTagFiber $matIDhard $d $bf $tf $tw $nfdw $nftw $nfbf $nftf"
invoked from within
"if {$SectionType == "Elastic"} {
# material properties:
set Es [expr 29000*$ksi]; # Steel Young's Modulus
set nu 0.3; # Poisson's ratio
set Gs ..."
(file "Ex8.genericFrame3D.build.Wsec.tcl" line 98)
invoked from within
"source Ex8.genericFrame3D.build.Wsec.tcl"
(file "test.tcl" line 3)

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To find an answer to dealing with errors like this.

https://portwooddigital.com/2019/10/06 ... sections/

I visited this site. This reason seems to occur for the same reason as what is said on this site. However, the descriptive method of the code is different, so I don't know how to fix it.

The code for the Wsection where the problem appears is as follows.

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proc Wsection { secID matID d bf tf tw nfdw nftw nfbf nftf} {
# ###################################################################
# Wsection $secID $matID $d $bf $tf $tw $nfdw $nftw $nfbf $nftf
# ###################################################################
# create a standard W section given the nominal section properties
# written: Remo M. de Souza
# date: 06/99
# modified: 08/99 (according to the new general modelbuilder)
# input parameters
# secID - section ID number
# matID - material ID number
# d = nominal depth
# tw = web thickness
# bf = flange width
# tf = flange thickness
# nfdw = number of fibers along web depth
# nftw = number of fibers along web thickness
# nfbf = number of fibers along flange width
# nftf = number of fibers along flange thickness

set dw [expr $d - 2 * $tf]
set y1 [expr -$d/2]
set y2 [expr -$dw/2]
set y3 [expr $dw/2]
set y4 [expr $d/2]

set z1 [expr -$bf/2]
set z2 [expr -$tw/2]
set z3 [expr $tw/2]
set z4 [expr $bf/2]

section fiberSec $secID {
# nfIJ nfJK yI zI yJ zJ yK zK yL zL
patch quadr $matID $nfbf $nftf $y1 $z4 $y1 $z1 $y2 $z1 $y2 $z4
patch quadr $matID $nftw $nfdw $y2 $z3 $y2 $z2 $y3 $z2 $y3 $z3
patch quadr $matID $nfbf $nftf $y3 $z4 $y3 $z1 $y4 $z1 $y4 $z4
}
}


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How can I overcome this warning?

[mhscott]

Code: Select all

section fiberSec $secID -GJ $GJ {
  patch ...
}