pattern UniformExcitation

[peyman1358]

Hi all,

I have got the same response from my bridge model when I am applying my ground motion in both longitudinal (dir. 1) and Transverse (dir. 2) by "pattern UniformExcitation" command.
Can you give me some guidance?

Thanks

[fmk]

check your input.
here's the result for the simplest 3d model i could think of with a motion applied to each dirn individually and then to both simultaneously:

[code]
DIRECTION: 1 DISP: -0.00003939050463397046 0.00000000000000000000
DIRECTION: 2 DISP: 0.00000000000000000000 -0.00031094105626236214
DIRECTION: 3 DISP: -0.00003939050463397046 -0.00031094105626236214
[/code]


[CODE]
foreach dirn {1 2 3} {

model basic -ndm 3 -ndf 6

node 1 0 0 0
node 2 0 0 100 -mass 10.0 10.0 10.0 0.0 0.0 0.0
node 3 200 0 0
node 4 200 0 100 -mass 20.0 20.0 20.0 0.0 0.0 0.0

fix 1 1 1 1 1 1 1
fix 3 1 1 1 1 1 1

set A 10.0; set E 29000; set G [expr $E/(2+0.6)]; set J 30.0; set Iy 100000; set Iz 50000;
section Elastic 1 $E $A $Iz $Iy $G $J

set beamT 1; set colT 2;
geomTransf Linear $beamT 0 0 -1;
geomTransf Linear $colT -1 0 0;

element elasticBeamColumn 1 1 2 $A $E $G $J $Iy $Iz $colT
element elasticBeamColumn 2 3 4 $A $E $G $J $Iy $Iz $colT
element elasticBeamColumn 3 2 4 $A $E $G $J $Iy $Iz $beamT

timeSeries Sine 1 0.0 20.0 2.0

if {$dirn == 1 || $dirn == 3} {
pattern UniformExcitation 1 1 -accel 1
}
if {$dirn == 2 || $dirn == 3} {
pattern UniformExcitation 2 2 -accel 1
}

numberer Plain
constraints Plain
test NormDispIncr 1.0e-12 3 0
algorithm Newton
integrator HHT 1.0
system ProfileSPD
analysis Transient
analyze 100 0.1

set node2 [nodeDisp 2]
puts "DIRN: $dirn DISP: [lindex $node2 0] [lindex $node2 1]"

wipe
}
[/CODE]