osp - mode shape

[r-m]

hi silvia

how can i use the osp for mode shape?

please help me

thanks alot

[silvia]

contact the osp author

[kishor]

Hello

I use to see mode shape through this way on OSP.

Step 1: Source the file procModalAnalysis.tcl (find it below)
Step 2. Run model in OpenSees, It will creat .eig file for mode shape.
Step 3: Open model on the OSP
Step 4: Open modeshape file

This should make you able to view modeshape.

Good Luck!!

##Example only
#quad element connected with BeamColumn element

# Set parameters for overall model geometry
set width 3600
set height 4440

# Create ModelBuilder (with two-dimensions and 3 DOF/node):
model basic -ndm 2 -ndf 3

# nodal coordinates:

node 1 0.0 0.0
node 2 $width 0.0
node 3 0.0 $height
node 4 $width $height

#boundry condition
fix 1 1 1 1
fix 2 1 1 1

# transformation:

geomTransf Linear 1

# connectivity:

element elasticBeamColumn 1 1 3 660 200 11864 1
element elasticBeamColumn 2 2 4 660 200 11864 1
element elasticBeamColumn 3 3 4 660 200 11864 1

# Load
pattern Plain 1 "Linear" {
load 3 100.0 -20.0 100.0
load 4 100.0 -0.0 0.0
}


# Create another ModelBuilder (with two-dimensions and 2 DOF/node)
model basic -ndm 2 -ndf 2

node 11 0.0 0.0 -mass 0.00003 0.0
node 12 $width 0.0 -mass 0.00003 0.0
node 13 0.0 $height -mass 0.00003 0.0
node 14 $width $height -mass 0.00003 0.0

fix 11 1 1
fix 12 1 1



nDMaterial ElasticIsotropic 1 200 0.3

#element quad $eleTag $iNode $jNode $kNode $lNode $thick $type $matTag <$pressure $rho $b1 $b2>
element quad 4 11 12 14 13 .000076 PlaneStress 1

# now force nodes 13 and 14 to have same disp as 3 and 4 in 1st and 2nd DOF.
equalDOF 3 13 1 2
equalDOF 4 14 1 2

# for shear model (Series of constraint, the constraints Transformation is not suitable)
equalDOF 13 14 1

#Mode Shape for OSP

source procModalAnalysis.tcl; #Create eig file that can be viewed at OSP (OpenSees Post processor), Name of the file that will be created is given on this source file, i.e, Diaphragm_ModeShape.eig in this case.
set N 1
ModalAnalysis $N
wipeAnalysis


pattern Plain 3 "Linear" {

# Create the nodal load - command: load nodeID xForce yForce

load 13 5 1 0


}


#set g 9810; # Gravitational constant
#set FN "Path -filePath SS160.txt -dt 0.0025 -factor $g"; # Earthquake Excitation file
# Define the excitation using the FN ground motion records
#pattern UniformExcitation 2 1 -accel $FN ; # create uniform excitation with IDtag 2 in direction 2


#Start of analysis:
test EnergyIncr 1.0e-8 10 3
# Create the solution algorithm
algorithm Newton
## Create the system of equation storage and solver (SPD solver can not be used if the constraints Lagrange is used as constraint handler)
system SparseGeneral -piv
# Create the constraint handler
constraints Lagrange
integrator Newmark 0.5 0.25

## Create the DOF numberer
numberer RCM
analysis Transient


recorder Node -file node11.out -time -node 11 -dof 1 disp
analyze 1000 0.01
print node 11 12 13 14
print node 1 2 3 4

wipeAnalysis

set lambda [eigen 1]
set omega [expr pow($lambda,0.5)]
set PI 3.142857
set Tperiod [expr 2*$PI/$omega]; # period (sec.)
puts $Tperiod

############################
###Source file procModalAnalysis.tcl
##############################
proc ModalAnalysis { nModes } {

#Wipe the analysis
wipeAnalysis

#Perform Eigen Value analysis
set eigenvalues [eigen $nModes ]

#Set up recorders for eigen vectors
set jjj 0
for {set jjj 0} {$jjj < $nModes} {incr jjj 1} {
recorder Node -file tempFile[expr {$jjj}].tmp -node all -dof 1 2 "eigen [expr $jjj + 1]"
###recorder Node tempFile[expr {$jjj}].tmp "eigen [expr $jjj + 1]" -node all -dof 1 2 ## this commond is not working
}

#Run a one step gravity load with no loading.
test EnergyIncr 1e-6 20 0
algorithm Newton
system SparseGeneral
integrator LoadControl 0 ;#1 .0000001 1
numberer Plain
constraints Transformation
analysis Static
analyze 1

#Wipe the analysis
wipeAnalysis

#Remove the recorders
remove recorders

#Create .eig file to view mode shape on OSP
set _fID [open Diaphragm_ModeShape.eig w]

#Open the temp files
for {set jjj 0} {$jjj < $nModes} {incr jjj 1} {
set _fIDt [open tempFile[expr {$jjj}].tmp]
set tempPeriod [expr 2*3.1416/sqrt([lindex $eigenvalues $jjj])]
set tempValues [read -nonewline $_fIDt]
puts $_fID "$tempPeriod $tempValues"
close $_fIDt
file delete tempFile[expr {$jjj}].tmp
}

#Close the .eig File
close $_fID
}

[dinochen1983]

in order to solve this problem, i will try my method, after i finish the new modal display method, i will show it on the forum, please wait

[r-m]

Dear Kishor

thank you very very much

[kishor]

we can view and record the time history analysis as well.