question about recorder a free node

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2015James
Posts: 31
Joined: Wed Dec 29, 2010 2:57 am
Location: hit

question about recorder a free node

Post by 2015James »

hi vesna, the folowing is model you built before could you tell me what is the reaction of node 2 ? if I recorder the reaction of node 1, i know the reaction of node 1is the support reaction,but what the reaction of node 2(a free node ) stand for? Thanks

# Canilever column from Chopra's book (Example 5.1)

wipe

model BasicBuilder -ndm 2 -ndf 3
set A1 1.0
set E [expr 10./3.]
set mass1 0.2533
set H 1.0
#set mass1 0.00001
set I1 1.0
set pi 3.14
set k [expr 3.*$I1*$E/$H**3]
puts "K: $k"
node 1 0.0 0.0
node 2 0.0 $H -mass $mass1 0.0 0.0

fix 1 1 1 1

geomTransf Linear 10
element elasticBeamColumn 1 1 2 $A1 $E $I1 10

set G 386.
timeSeries Path 2 -dt 0.005 -filePath A10000.acc -factor $G; # define acceleration vector from file (dt=0.005 is associated with the input file gm)
pattern UniformExcitation 2 1 -accel 2;


recorder Node -file point_2_ResistingForce.out -time -node 2 -dof 1 reaction


set lambda [eigen -fullGenLapack 1]
set T [expr (2*$pi)/sqrt($lambda)]
puts "T = $T"
set freq [expr sqrt($lambda)]
set dampRatio 0.05
rayleigh [expr 2.*$dampRatio*$freq] 0. 0. 0.


#integrator Newmark 0.5 [expr 1./6.]
integrator Newmark 0.5 0.25
test EnergyIncr 1.0e-6 20 1
algorithm Linear
numberer Plain
constraints Plain
system BandGeneral

analysis Transient
analyze 3995 0.01; # apply 3995 0.01-sec time steps in analysis

print -node 2

what is the reaction of node 2 ?
vesna
Posts: 3033
Joined: Tue May 23, 2006 11:23 am
Location: UC Berkeley

Re: question about recorder a free node

Post by vesna »

It is the unbalanced load.
2015James
Posts: 31
Joined: Wed Dec 29, 2010 2:57 am
Location: hit

Re: question about recorder a free node

Post by 2015James »

vesna wrote:
> It is the unbalanced load.
Thanks for your prompt reply vesna.
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