dynamic analysis

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moshtagh
Posts: 18
Joined: Mon Oct 03, 2011 1:23 am
Location: urmia

dynamic analysis

Post by moshtagh »

Hi every body
I have an problem with dynamic analysis!!
I want to know, if I want to use analysis Transient for dynamic analysis, I should only use ground motion or accelerate on my structure? Because I have an 3D space structure, I define mass, damping, load and analysis as following. But the opensees failed and give me warning. Why? Please help me!

model BasicBuilder -ndm 3 -ndf 3
node 1 2 2 2.828
node 2 6 2 2.828
.
.
.
node 60 16 20 0
node 61 20 20 0

fix 26 1 1 1 0 0 0
fix 31 0 0 1 0 0 0
fix 56 0 0 1 0 0 0
fix 61 1 0 1 0 0 0

mass 1 0 0 -3600 0 0 0
mass 2 0 0 -3600 0 0 0
.
.
.
mass 24 0 0 -3600 0 0 0
mass 25 0 0 -3600 0 0 0

uniaxialMaterial Hysteretic 1 3.4e8 0.001619 34.84e7 0.002 35.26e7 0.003 -53394779.58 -0.000875 -37014269.14 -0.002625 -23138051.04 -0.006875 0 0 0 0
uniaxialMaterial Hysteretic 2 3.4e8 0.001619 34.84e7 0.002 35.26e7 0.003 -81305804 -0.000875 -44329911 -0.003375 -30897857 -0.006875 0 0 0 0
uniaxialMaterial Hysteretic 3 3.4e8 0.001619 34.84e7 0.002 35.26e7 0.003 -81280841 -0.000875 -50293458 -0.002625 -30899393 -0.006875 0 0 0 0
uniaxialMaterial Hysteretic 4 3.4e8 0.001619 34.84e7 0.002 35.26e7 0.003-110000000 -0.001125 -82178409 -0.001625 -39451515 -0.006875 0 0 0 0

element corotTruss 1 1 2 0.00214 3
element corotTruss 2 2 3 0.00264 4
.
.
.
element corotTruss 199 60 25 0.000862 1
element corotTruss 200 61 25 0.00264 4

set khati1 "Series -time {0.0 5 10 15 20} -values {0.0 5 10 10 10}"
set p 1
pattern Plain 2 $khati1 {
# node FX FY FZ
load 1 0 0 -36000 0 0 0
load 2 0 0 -36000 0 0 0
.
.
.
load 24 0 0 -36000 0 0 0
load 25 0 0 -36000 0 0 0

rayleigh 0.21543 0.001024 0.001024 0.001024
integrator Newmark 0.5 0.25
test NormUnbalance 10000 10
algorithm Newton
numberer RCM
constraints Plain
system ProfileSPD
analysis Transient
analyze 10 1 1

WARNING: CTestNormUnbalance::test<> - failed to converge
Aftar: 10 iterations
NewtnRaphson::solveCurrentStep<> -the ConvergenceTest object failed in test<>
DirectIntegrationAnalysisi::analyze<> - the Algorithm failed at time 1
OpenSees > analyze failed, returned: -3 error flag
-3


I think that my fault is my loading, because my loading doesn’t apply any accelerate on my structure! Is it correct?
Please help me
Thanks alot
mehrdadmaster
Posts: 3
Joined: Wed Sep 05, 2012 1:43 pm
Location: urmia

Re: dynamic analysis

Post by mehrdadmaster »

hi
you should apply the load in fy direction.
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