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Thank you for answer.

As you have mentioned, I have applied the 'displacementBeamColumn'.
But it continue to stop working on the opensees, can you tell us why?

Thank you

I received a cable bridge structure model built with Opensees, but the problem is that only the linear behavior is applied and the displacement is very small.

So I used the 'ForceBeamColumn' element to take into account the material nonlinearity only in the pylon, but only the part of the changed element is an error that failed to get compatible element forces&deformations for element.

I'd appreciate it if you could tell me why this error occurred.

Thank you.

hello

I have a problem when run FORM analysis in opensees.

I attach my code below.
I would like to know why running this code will cause opensees to stop working.
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puts "DonePushover"

reliability
randomVariable 1 lognormal -mean $Hload -stdv [expr 0.1*$Hload]

parameter 10 randomVariable 1 loadPattern 2 loadAtNode 2 1

performanceFunction 11 "7.0e-17 -\[nodeDisp 2 1\]"

gradPerformanceFunction 11 1 "-\[sensNodeDisp 2 1 11\]"


# FORM analysis option

sensitivityIntegrator -static
sensitivityAlgorithm -computeAtEachStep

randomNumberGenerator CStdLib

probabilityTransformation Nataf -print 3

reliabilityConvergenceCheck Standard -e1 1.0e-2 -e2 1.0e-2 -print 1

functionEvaluator Tcl -file "analyze 1"

gradientEvaluator OpenSees
searchDirection iHLRF
meritFunctionCheck AdkZhang -multi 2.0 -add 50 -factor 0.5
stepSizeRule Armijo -maxNum 10 -base 0.5 -initial 0.3 5
startPoint Mean
findDesignPoint StepSearch -maxNumIter 30
runFORMAnalysis matnonlinear_FOSM.txt
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Hi
I am looking for help on the code I have which include the reliability analysis.
The problem I have is gradient value of RV with tag 1 is zero.
Can you explain why the problem express?

model BasicBuilder -ndm 2 -ndf 2

# Create nodes
# ------------
set len [expr 100*sqrt(2)]
# Create nodes & add to Domain - command: node nodeId xCrd yCrd
node 1 0.0 0.0
node 2 110 0.0
node 3 220 0
node 4 330 0
node 5 440 0
node 6 110 110
node 7 220 110
node 8 330 110

# Set the boundary conditions - command: fix nodeID xResrnt? yRestrnt?
fix 1 1 1 0;
fix 2 0 0 0
fix 3 0 0 0
fix 4 0 0 0
fix 5 0 0 0
fix 6 1 0 0
fix 7 0 0 0
fix 8 0 0 0

# Define materials for truss elements
# -----------------------------------

# Create Elastic material prototype - command: uniaxialMaterial Elastic matID E
uniaxialMaterial Elastic 1 7063200

# Define elements
# ---------------

# Create truss elements - command: element truss trussID node1 node2 A matID


element Truss 1 1 2 250 1
element Truss 2 2 3 250 1
element Truss 3 3 4 250 1
element Truss 4 4 5 250 1
element Truss 5 6 7 250 1
element Truss 6 7 8 250 1
element Truss 7 1 6 250 1
element Truss 8 2 6 250 1
element Truss 9 3 6 260 1
element Truss 10 3 7 240 1
element Truss 11 3 8 240 1
element Truss 12 4 8 240 1
element Truss 13 5 8 240 1



# Define loads
# ------------

#create a Linear TimeSeries (load factor varies linearly with time): command timeSeries Linear $tag
timeSeries Linear 1

# Create a Plain load pattern with a linear TimeSeries: command pattern Plain $tag $timeSeriesTag { $loads }
pattern Plain 1 1 {

# Create the nodal load - command: load nodeID xForce yForce
load 7 0 -50
}

# ------------------------------
# Start of analysis generation
# ------------------------------

# Create the system of equation, a SPD using a band storage scheme
system BandSPD

# Create the DOF numberer, the reverse Cuthill-McKee algorithm
numberer RCM

# Create the constraint handler, a Plain handler is used as homo constraints
constraints Plain

# Create the integration scheme, the LoadControl scheme using steps of 1.0
integrator LoadControl 1.0

# Create the solution algorithm, a Linear algorithm is created
algorithm Linear

# create the analysis object
analysis Static

# ------------------------------
# Start of recorder generation
# ------------------------------

# create a Recorder object for the nodal displacements at node 7
recorder Node -file node7.txt -time -node 7 -dof 1 2 -precision 16 disp

# Create a recorder for element forces, one in global and the other local system
recorder Element -file eledisp.txt -time -ele 1 2 3 disp
recorder Element -file eleGlobalforce.txt -time -ele 1 2 3 forces
recorder Element -file eleLocal.txt -time -ele 1 2 3 basicForces

# ------------------------------
# Finally perform the analysis
# ------------------------------

# Perform the analysis
analyze 1

# ------------------------------
# Print Stuff to Screen
# ------------------------------

# Print the current state at node 4 and at all elements

puts "done"

reliability

set M 250

randomVariable 1 normal -mean $M -sdv [expr $M*0.1]
randomVariable 2 normal -mean $M -sdv [expr $M*0.1]
randomVariable 3 normal -mean $M -sdv [expr $M*0.1]
randomVariable 4 normal -mean $M -sdv [expr $M*0.1]

parameter 1 randomVariable 1 element 1 A
parameter 2 randomVariable 2 element 2 A
parameter 3 randomVariable 3 element 3 A
parameter 4 randomVariable 4 element 4 A


set Nsteps [expr int(1.0/0.01)]

performanceFunction 1 "3e-5-\[nodeDisp 7 2\]"

randomNumberGenerator CStdLib
probabilityTransformation Nataf -print 3
reliabilityConvergenceCheck Standard -e1 1.0e-2 -e2 1.0e-2 -print 1
functionEvaluator Tcl -file "analyze $Nsteps"
gradientEvaluator FiniteDifference
gradientEvaluator Implicit
searchDirection iHLRF
meritFunctionCheck AdkZhang -multi 2.0 -add 10.0 -factor 0.5
stepSizeRule Armijo -maxNum 10 -base 0.5 -initial 0.3 5
stepSizeRule Fixed -stepSize 1.0
startPoint Mean
findDesignPoint StepSearch -maxNumIter 15 -printDesignPointX designPointX.out

runFORMAnalysis industrialFrame.out

puts "done"

I want to know about FORM Analysis option.

hello

I need some static structural reliability example and FORM Analysis command.
please let me some example.

thanks

Hi
I have a question about reliability analysis used opensees.

I know it is possible to compute DDM(Direct differentiation method) based sensitivity.
But is it possible to compute FFD(Forward finite difference) based sensitivity?