I'm tring to make spring model using zerolength.
so I worte the script and model is builted.
But I have some questions about model
1. natural frequency.
I want to make natural frequency 1 model.
so I used "set lamda [eigen 1]" command. but error coms out.
what is problem?
This is error
"ArpackSolver::Error with _saupd info = -9999
Could not build an Arnoldi factorization.IPARAM(5) the size of the current Arnoldi factorization: is 1factorization. The user is advised to check thatenough workspace and array storage has been allocated.
WARNING DirectIntegrationAnalysis::eigen() - EigenSOE failed in solve()"
2.damping
I tried to make 0.05 damping ratio model.
but I dont have any idea about that.
so can you guys give me some tips?
Thanks for answer.
This is my script.
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wipe all;
model BasicBuilder -ndm 2 -ndf 3;
set mass 5.908;
# variable
set L 3500;
set A [expr 200*200];
set I [expr 1./12.*200*pow(200,3)];
set E 30000;
# nodal coordinates:
node 1 0 0; # node#, X, Y
node 2 0 0;
node 3 0 $L
fix 1 1 1 1; # node DX DY RZ
fix 3 0 1 1; # node DX DY RZ
mass 3 $mass $mass 0.;
equalDOF 1 2 1 2 3
set Es 29000.0; # steel Young's modulus
set Fy 7.5; # Section's yielding stress
set b 0.05; # strain-hardening ratio (ratio between post-yield tangent and initial elastic tangent)
set steel01matID 1
uniaxialMaterial Steel01 $steel01matID $Es $Fy $b
element zeroLength 1 1 2 -mat $steel01matID -dir 2
geomTransf Linear 1
element elasticBeamColumn 2 2 3 $A $E $I 1
# Define Time Series
set GMfile "eq(test).acc"; # load tag
set dt 0.01; # time step for input ground motion
set AccelSeries "Series -dt $dt -filePath $GMfile -factor 9.81"; # time series information
pattern UniformExcitation 1 1 -accel $AccelSeries ; # create Unifform excitation
timeSeries Path 1001 -dt 0.02 -filePath simqke_test1_dt0.01.acc -factor 9.81
# records
#recorder Node -file disp.txt -time -node 2 -dof 1 2 disp;
recorder Node -file disp.out -time -node 3 -dof 1 2 disp;
recorder Node -file Aabs.out -timeSeries 1001 -time -node 3 -dof 1 accel; # absolute acceleration
recorder Element -file force2.out -time -ele 2 globalForce;
integrator Newmark 0.5 0.25
test EnergyIncr 1.0e-8 10 0
algorithm ModifiedNewton
numberer Plain
constraints Transformation
system SparseGeneral -piv
analysis Transient
analyze 2100 0.01
puts "Done"