Eigen analysis of a 10-story 3-bay frame

[Rattan]

Dear users:
I create a 10-story 3-bay 3DOF model; when I run an eigen analysis ,the error is
"FullGenEigenSolver::solve() - the eigenvalue 1 is numerically undetermined or infinite
FullGenEigenSolver::solve() - the eigenvalue 2 is numerically undetermined or infinite
T1=4.686213860245912e-154 T2=4.686213860245912e-154"

I will appreciate any help or suggestions.

This is the tlc script related to the frame:（Because of the large amount of content, I omitted some unimportant code）


wipe
puts "System"
model basic -ndm 3 -ndf 6
puts "restraint"
set H1 4400;
set H2 3300;
set L1 6000;
set L2 2400;

#####Node of stirrup dense################
set HC1 675;
set HC2 600;
set HB 750;
#######################################


node 1 0 0 0
node 2 0 0 $H1
node 3 0 0 [expr $H1+$H2]
node 4 0 0 [expr $H1+2*$H2]
node 5 0 0 [expr $H1+3*$H2]
node 6 0 0 [expr $H1+4*$H2]
node 7 0 0 [expr $H1+5*$H2]
node 8 0 0 [expr $H1+6*$H2]
node 9 0 0 [expr $H1+7*$H2]
node 10 0 0 [expr $H1+8*$H2]
node 11 0 0 [expr $H1+9*$H2]

node 12 $L1 0 0
node 13 $L1 0 $H1
node 14 $L1 0 [expr $H1+$H2]
node 15 $L1 0 [expr $H1+2*$H2]
node 16 $L1 0 [expr $H1+3*$H2]
node 17 $L1 0 [expr $H1+4*$H2]
node 18 $L1 0 [expr $H1+5*$H2]
node 19 $L1 0 [expr $H1+6*$H2]
node 20 $L1 0 [expr $H1+7*$H2]
node 21 $L1 0 [expr $H1+8*$H2]
node 22 $L1 0 [expr $H1+9*$H2]

node 23 [expr $L1+$L2] 0 0
node 24 [expr $L1+$L2] 0 $H1
node 25 [expr $L1+$L2] 0 [expr $H1+$H2]
node 26 [expr $L1+$L2] 0 [expr $H1+2*$H2]
node 27 [expr $L1+$L2] 0 [expr $H1+3*$H2]
node 28 [expr $L1+$L2] 0 [expr $H1+4*$H2]
node 29 [expr $L1+$L2] 0 [expr $H1+5*$H2]
node 30 [expr $L1+$L2] 0 [expr $H1+6*$H2]
node 31 [expr $L1+$L2] 0 [expr $H1+7*$H2]
node 32 [expr $L1+$L2] 0 [expr $H1+8*$H2]
node 33 [expr $L1+$L2] 0 [expr $H1+9*$H2]

node 34 [expr 2*$L1+$L2] 0 0
node 35 [expr 2*$L1+$L2] 0 $H1
node 36 [expr 2*$L1+$L2] 0 [expr $H1+$H2]
node 37 [expr 2*$L1+$L2] 0 [expr $H1+2*$H2]
node 38 [expr 2*$L1+$L2] 0 [expr $H1+3*$H2]
node 39 [expr 2*$L1+$L2] 0 [expr $H1+4*$H2]
node 40 [expr 2*$L1+$L2] 0 [expr $H1+5*$H2]
node 41 [expr 2*$L1+$L2] 0 [expr $H1+6*$H2]
node 42 [expr 2*$L1+$L2] 0 [expr $H1+7*$H2]
node 43 [expr 2*$L1+$L2] 0 [expr $H1+8*$H2]
node 44 [expr 2*$L1+$L2] 0 [expr $H1+9*$H2]

############################Node of stirrup######################
node 45 0 0 $HC1
node 46 0 0 [expr $H1-$HC1]
node 47 0 0 [expr $H1+$HC2]
node 48 0 0 [expr $H1+$H2-$HC2]
node 49 0 0 [expr $H1+$H2+$HC2]
.................

node 161 $HB 0 [expr $H1+9*$H2]
node 162 [expr $L1-$HB] 0 [expr $H1+9*$H2]
node 163 [expr $L2+$L1+$HB] 0 [expr $H1+9*$H2]
node 164 [expr 2*$L2+$L1-$HB] 0 [expr $H1+9*$H2]



puts "mass"
mass 1 1.070E+000 0.000E+000 1.070E+000 0.000E+000 0.000E+000 0.000E+000
mass 2 7.604E+000 0.000E+000 7.604E+000 0.000E+000 0.000E+000 0.000E+000
mass 3 7.177E+000 0.000E+000 7.177E+000 0.000E+000 0.000E+000 0.000E+000
mass 4 7.177E+000 0.000E+000 7.177E+000 0.000E+000 0.000E+000 0.000E+000
mass 5 7.177E+000 0.000E+000 7.177E+000 0.000E+000 0.000E+000 0.000E+000
mass 6 7.177E+000 0.000E+000 7.177E+000 0.000E+000 0.000E+000 0.000E+000
mass 7 7.177E+000 0.000E+000 7.177E+000 0.000E+000 0.000E+000 0.000E+000
mass 8 7.177E+000 0.000E+000 7.177E+000 0.000E+000 0.000E+000 0.000E+000
mass 9 7.177E+000 0.000E+000 7.177E+000 0.000E+000 0.000E+000 0.000E+000
mass 10 7.177E+000 0.000E+000 7.177E+000 0.000E+000 0.000E+000 0.000E+000
mass 11 4.756E+000 0.000E+000 4.756E+000 0.000E+000 0.000E+000 0.000E+000
mass 12 1.070E+000 0.000E+000 1.070E+000 0.000E+000 0.000E+000 0.000E+000
mass 13 8.910E+000 0.000E+000 8.910E+000 0.000E+000 0.000E+000 0.000E+000
mass 14 8.492E+000 0.000E+000 8.492E+000 0.000E+000 0.000E+000 0.000E+000
mass 15 8.492E+000 0.000E+000 8.492E+000 0.000E+000 0.000E+000 0.000E+000
mass 16 8.492E+000 0.000E+000 8.492E+000 0.000E+000 0.000E+000 0.000E+000
mass 17 8.492E+000 0.000E+000 8.492E+000 0.000E+000 0.000E+000 0.000E+000
mass 18 8.492E+000 0.000E+000 8.492E+000 0.000E+000 0.000E+000 0.000E+000
mass 19 8.492E+000 0.000E+000 8.492E+000 0.000E+000 0.000E+000 0.000E+000
mass 20 8.492E+000 0.000E+000 8.492E+000 0.000E+000 0.000E+000 0.000E+000
mass 21 8.492E+000 0.000E+000 8.492E+000 0.000E+000 0.000E+000 0.000E+000
mass 22 6.163E+000 0.000E+000 6.163E+000 0.000E+000 0.000E+000 0.000E+000
mass 23 1.070E+000 0.000E+000 1.070E+000 0.000E+000 0.000E+000 0.000E+000
mass 24 8.910E+000 0.000E+000 8.910E+000 0.000E+000 0.000E+000 0.000E+000
mass 25 8.492E+000 0.000E+000 8.492E+000 0.000E+000 0.000E+000 0.000E+000
mass 26 8.492E+000 0.000E+000 8.492E+000 0.000E+000 0.000E+000 0.000E+000
mass 27 8.492E+000 0.000E+000 8.492E+000 0.000E+000 0.000E+000 0.000E+000
mass 28 8.492E+000 0.000E+000 8.492E+000 0.000E+000 0.000E+000 0.000E+000
mass 29 8.492E+000 0.000E+000 8.492E+000 0.000E+000 0.000E+000 0.000E+000
mass 30 8.492E+000 0.000E+000 8.492E+000 0.000E+000 0.000E+000 0.000E+000
mass 31 8.492E+000 0.000E+000 8.492E+000 0.000E+000 0.000E+000 0.000E+000
mass 32 8.492E+000 0.000E+000 8.492E+000 0.000E+000 0.000E+000 0.000E+000
mass 33 6.163E+000 0.000E+000 6.163E+000 0.000E+000 0.000E+000 0.000E+000
mass 34 1.070E+000 0.000E+000 1.070E+000 0.000E+000 0.000E+000 0.000E+000
mass 35 7.604E+000 0.000E+000 7.604E+000 0.000E+000 0.000E+000 0.000E+000
mass 36 7.177E+000 0.000E+000 7.177E+000 0.000E+000 0.000E+000 0.000E+000
mass 37 7.177E+000 0.000E+000 7.177E+000 0.000E+000 0.000E+000 0.000E+000
mass 38 7.177E+000 0.000E+000 7.177E+000 0.000E+000 0.000E+000 0.000E+000
mass 39 7.177E+000 0.000E+000 7.177E+000 0.000E+000 0.000E+000 0.000E+000
mass 40 7.177E+000 0.000E+000 7.177E+000 0.000E+000 0.000E+000 0.000E+000
mass 41 7.177E+000 0.000E+000 7.177E+000 0.000E+000 0.000E+000 0.000E+000
mass 42 7.177E+000 0.000E+000 7.177E+000 0.000E+000 0.000E+000 0.000E+000
mass 43 7.177E+000 0.000E+000 7.177E+000 0.000E+000 0.000E+000 0.000E+000
mass 44 4.756E+000 0.000E+000 4.756E+000 0.000E+000 0.000E+000 0.000E+000



puts "node"
fix 1 1 1 1 1 1 1;
fix 12 1 1 1 1 1 1;
fix 23 1 1 1 1 1 1;
fix 34 1 1 1 1 1 1;

puts "material"
>>>>>>>>>>>
puts "element"

element dispBeamColumn 1 1 45 3 10 1
element dispBeamColumn 2 45 46 3 11 1
element dispBeamColumn 3 46 2 3 10 1
>>>>>>>>>>>>
pattern Plain 1 Linear {
load 1 0 0 -$N1 0 0 0
load 12 0 0 -$N2 0 0 0
load 23 0 0 -$N2 0 0 0
load 34 0 0 -$N1 0 0 0
load 2 0 0 -$N3 0 0 0
load 13 0 0 -$N4 0 0 0
>>>>>>>>>>>>
}
#Eigenvalue analysis
set pi 3.14159265;
set nEigeni 1;
set nEigenj 2;
set lambdaN [eigen -fullGenLapack [expr $nEigenj]];
set lambda1 [lindex $lambdaN [expr $nEigeni-1]];
set lambda2 [lindex $lambdaN [expr $nEigenj-1]];

set w1 [expr pow($lambda1,0.5)];
set w2 [expr pow($lambda2,0.5)];
set T1 [expr 2.0*$pi/$w1];
set T2 [expr 2.0*$pi/$w2];

puts "$T1 $T2"

[mhscott]

Check the connectivity of the elements in your model. You likely have a mechanism.