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Thank you very much

I will try what you said.

thanks


Aizen

Thanks Carlos for your help

I will try to check it

Dear Fmk

Several days have passed waiting for a kind reply.

Can you help me please?


I am sorry to bother you but I need of help



thanks

Dear Fmk

I have posted my files as you have requested.

I am sorry for my previous error of sending you the files.

Please, Can you help me?


thanks so much


Aizen

Dear fmk

I have sent you the files only due to the lenght of the inputs file. I am sorry If I have given you problems.

I post here my model file. The file LibAnalysisDynamicParameters.tcl is the original one.

My questions are the same:

1.I have to simulate a top hinge release.
Continuous girder is supported by 3d top hinge pier connection.
equalDOF does not work in my case (block1). Why is it? Why i can not use very small stifness for the rotation when I use zerolenght element (block 2)?

2.I have not changed any parameter in the LibAnalysisDynamicParameters.tcl
also if I am now studing a bridge with different support displacement hystory. Is it correct?

3.To use RAYLEIGH damping I have to use the modal analysis in opensees. I have only three DOF along the y direction but for having three modes in opensees, I have to use other three masses (6 DOF) along the x direction.
Is it sure that using small masses along the x direction, I have not changed the response of the bridge for different support displacements hystory analysis?


wipe;
model BasicBuilder -ndm 3 -ndf 6;
file mkdir Data;

set RIGIDFACTOR 10000000;

set L_pier 6;
set L_deck 22;
set A_pier [expr 16*$RIGIDFACTOR];
set A_deck [expr 11*$RIGIDFACTOR];
set Iz_pier 21;
set Iz_deck 100;
set J_pier [expr 41*$RIGIDFACTOR];
set J_deck [expr 10*$RIGIDFACTOR];
set Iy_pier 21;
set Iy_deck 3;
set Ec_pier 34000000;
set Ec_deck 32000000;
set Gc_pier 14000000;
set Gc_deck 13000000;

node 1 0 0 $L_pier;
node 2 $L_deck 0 $L_pier;
node 3 [expr 2*$L_deck ] 0 $L_pier;
node 4 0 0 $L_pier;
node 5 $L_deck 0 $L_pier;
node 6 [expr 2*$L_deck ] 0 $L_pier;
node 7 0 0 0;
node 8 $L_deck 0 0;
node 9 [expr 2*$L_deck] 0 0;

set MINFACTOR 10e-12;
set Mc 600;
set Ml 300;

mass 1 [expr $Ml*$MINFACTOR] $Ml 0 0 0 0;
mass 2 [expr $Mc*$MINFACTOR] $Mc 0 0 0 0;
mass 3 [expr $Ml*$MINFACTOR] $Ml 0 0 0 0;

fix 7 1 1 1 1 1 1;
fix 8 1 1 1 1 1 1;
fix 9 1 1 1 1 1 1;

# block 1
equalDOF 1 4 1 2 3;
equalDOF 2 5 1 2 3;
equalDOF 3 6 1 2 3;
# block 1

set pierTransfTag 1;
set deckTransfTag 2;

geomTransf Linear $pierTransfTag -1 0 0;
geomTransf Linear $deckTransfTag 0 0 1 ;

element elasticBeamColumn 1 1 2 $A_deck $Ec_deck $Gc_deck $J_deck $Iy_deck $Iz_deck $deckTransfTag;
element elasticBeamColumn 2 2 3 $A_deck $Ec_deck $Gc_deck $J_deck $Iy_deck $Iz_deck $deckTransfTag;

element elasticBeamColumn 3 4 7 $A_pier $Ec_pier $Gc_pier $J_pier $Iy_pier $Iz_pier $pierTransfTag;
element elasticBeamColumn 4 5 8 $A_pier $Ec_pier $Gc_pier $J_pier $Iy_pier $Iz_pier $pierTransfTag;
element elasticBeamColumn 5 6 9 $A_pier $Ec_pier $Gc_pier $J_pier $Iy_pier $Iz_pier $pierTransfTag;

# block 2
# uniaxialMaterial Elastic 1 1000000000000;
# uniaxialMaterial Elastic 2 0.01; # if I use value less than 0.01 it does not work. for example if I use 0.001

# element zeroLength 14 1 4 -mat 1 1 1 2 2 2 -dir 1 2 3 4 5 6;
# element zeroLength 25 2 5 -mat 1 1 1 2 2 2 -dir 1 2 3 4 5 6;
# element zeroLength 36 3 6 -mat 1 1 1 2 2 2 -dir 1 2 3 4 5 6;
# block 2

recorder Node -file Data/nodes.out -time -node 9 8 7 3 2 1 -dof 2 disp;

set Pz_deck 300;
pattern Plain 1 Linear {
eleLoad -ele 1 -type -beamUniform 0. -$Pz_deck 0.;
eleLoad -ele 2 -type -beamUniform 0. -$Pz_deck 0.;
eleLoad -ele 3 -type -beamUniform 0. -$Pz_deck 0.;
}

# Gravity-analysis parameters -- load-controlled static analysis
set Tol 1.0e-8;# convergence tolerance for test
variable constraintsTypeGravity Plain;# default;
constraints $constraintsTypeGravity ;# how it handles boundary conditions
numberer RCM;# renumber dof's to minimize band-width (optimization), if you want to
system BandGeneral ;# how to store and solve the system of equations in the analysis (large model: try UmfPack)
test EnergyIncr $Tol 6 ;# determine if convergence has been achieved at the end of an iteration step
algorithm Newton;# use Newton's solution algorithm: updates tangent stiffness at every iteration
set NstepGravity 10;# apply gravity in 10 steps
set DGravity [expr 1./$NstepGravity];# first load increment;
integrator LoadControl $DGravity;# determine the next time step for an analysis
analysis Static;# define type of analysis static or transient
analyze $NstepGravity;# apply gravity
# ------------------------------------------------- maintain constant gravity loads and reset time to zero
loadConst -time 0.0

# ------------ define & apply damping
# RAYLEIGH damping parameters, Where to put M/K-prop damping, switches
# D=$alphaM*M + $betaKcurr*Kcurrent + $betaKcomm*KlastCommit + $beatKinit*$Kinitial
set xDamp 0.02; # damping ratio FOR BRIDGE
set MpropSwitch 1.0;
set KcurrSwitch 0.0;
set KcommSwitch 1.0;
set KinitSwitch 0.0;

set N_modes 3;
set nEigenI 1;
set nEigenJ 2;
set lambdaN [eigen [expr $N_modes]]; # eigenvalue analysis for nEigenJ modes
set lambdaI [lindex $lambdaN [expr $nEigenI-1]]; # eigenvalue mode i
set lambdaJ [lindex $lambdaN [expr $nEigenJ-1]]; # eigenvalue mode j
set omegaI [expr pow($lambdaI,0.5)];
set omegaJ [expr pow($lambdaJ,0.5)];
set alphaM [expr $MpropSwitch*$xDamp*(2*$omegaI*$omegaJ)/($omegaI+$omegaJ)]; # M-prop. damping; D = alphaM*M
set betaKcurr [expr $KcurrSwitch*2.*$xDamp/($omegaI+$omegaJ)]; # current-K; +beatKcurr*KCurrent
set betaKcomm [expr $KcommSwitch*2.*$xDamp/($omegaI+$omegaJ)]; # last-committed K; +betaKcomm*KlastCommitt
set betaKinit [expr $KinitSwitch*2.*$xDamp/($omegaI+$omegaJ)]; # initial-K; +beatKinit*Kini
rayleigh $alphaM $betaKcurr $betaKinit $betaKcomm;

# MultipleSupport Earthquake ground motion (different displacement input at spec'd support nodes) -- two nodes here
# ground-motion input:
set iSupportNode "7 8 9" ;# support nodes where ground motions are input, for multiple-support excitation
set iGMdirection "2 2 2"; #ground-motion direction -- for each support node
set iGMfact "1 1 1"; # ground-motion scaling factor -- for each support node
set iGMfile "uy1 uy2 uy3";
set dt 0.01
# set up ground-motion-analysis parameters
set DtAnalysis 0.01; # time-step Dt
set TmaxAnalysis 20.; # maximum duration of ground-motion analysis

# ----------- set up analysis parameters
source LibAnalysisDynamicParameters.tcl; # constraintsHandler,DOFnumberer,system-ofequations,convergenceTest,solutionAlgorithm,integrator

# --------------------------------- perform Dynamic Ground-Motion Analysis
# the following commands are unique to the Multiple-Support Earthquake excitation
set IDloadTag 700;
set IDgmSeries 1; # for multipleSupport Excitation
set GMdir INPUT
# multiple-support excitation: displacement input at individual nodes
pattern MultipleSupport $IDloadTag {
foreach SupportNode $iSupportNode GMfile $iGMfile GMfact $iGMfact GMdirection $iGMdirection {
set IDgmSeries [expr $IDgmSeries +1]
set outFile $GMdir/$GMfile.TCL;
set DispSeries "Series -dt $dt -filePath $outFile -factor $GMfact"; # time series information
groundMotion $IDgmSeries Plain -disp $DispSeries
imposedMotion $SupportNode $GMdirection $IDgmSeries
}; # end foreach
}; # end pattern

set Nsteps [expr int($TmaxAnalysis/$DtAnalysis)];
set ok [analyze $Nsteps $DtAnalysis];
# exit

Best Regards

Aizen

Dear fmk


I have received a email with alink for a private message but it is not possible to read it.

Private messaging has been disabled on this board.

Can you help me?


aizen

Dear fmk


should I post my file here to have an answer?

can you help me?


thanks


Aizen

Dear Fmk

I am sorry if I post again my request.

Thank you very much for all the help thus far.

I just wanted to know if I was wrong to send files via email.

Now you can see my files I would want confirmation on:

Why does not equalDOF work?

Why I can not use a very low stiffness to simulate rotational release?

is it correct to use that small masses
to have the number of modes that I need or I alter the analysis?

Can I use parameter file (LibAnalysisDynamicParameters.tcl) for my problem without change it?

Can you help me?

Thanks

cordially

Aizen

Dear Fmk

Thank you very much for your help

I have sent my files:

model file

parameter analisys file

ground motion inputs


Cordially


Aizen

Thanks fmk


I have used two nodes (1 and 2) with the same coordinates at the top of the column and the command :

equalDOF 1 2 1 2 3;

to create a 3D hinge (tghe two nodes have to be restrained only to have the same translation).


1) What do you mean?

2) I have to run the same type of analysis used in the example:

Dynamic Multiple-Support Earthquake Ground Motion

I have not change the file:

LibAnalysisDynamicParameters.tcl

and my structure is very simple:


a bridge with 8 piers and a continuous beam deck. A the top of the piers i have to use hinges to support the deck.

The problem is elastic and I use elasticBeamColumn element.

What should I change?

thanks

however I have controlled the results in the case in which I use the zerolenght element with a hight stiffness for the x y z direction and a low (0.01) stifness for the rotation and the results are similar to the ones given by other program.

I would only understand is the low stiffness can be reduced and if the model is correct or if in other analysis or in some cases the model can give error or wrong results


aizen

Dear all

I have to simulate an end release (3D hinge at the top of the column ) at one extreme of a element.

I have read that the solutions are two:

use equalDOF (In my case it does not work; error BandLinLapcksolver::solve()-LAPACK routine returned 52...static analysis...the algoritm failed at iteration:0 with domain at load factor 0.1 )

use a zerolenght element with a low stiffness for the rotation around x,y,z and a high stiffness for the traslation displacement along x, y, z.


If I use:

uniaxialMaterial Elastic 1 1000000000000;
uniaxialMaterial Elastic 2 0.001;
element zeroLength 1 1 2 -mat 1 1 1 2 2 2 -dir 1 2 3 4 5 6;

Opensees shows an error message :
domain error: argument not in valid range

If I use for Elastic 2 a value greater than 0.01 Opensees works.

What is the problem?

thanks

Dear FMK

thank you a lot.

thanks for your kind answers.

I will try to use this element.

is it possible to have a reference of the author of this element (author of the theory and the author of the implementation in opensees) to study carefully the use and the geometrical limits?

thanks

aizen

Can someone help me?

Dear all

Can someone help me?

I thank FMk for his help but my problem for now it is not the shear deformation that I have to consider later.

I am not sure about the type of element implemented in noninearbeamcolumn element and so I have not reference about the limits geometrical in the use of this element (ration between diameter of the fiber section and the height of the element)


My problem is simple.

I have to model one r.c. column with a particular base section where deformation are concentrated.

At the base I have greater rotation concentrated (hinge at the base).

I have to apply a vertical load and a cyclic horizzontal displacements history at the top of the column

In my first test I have used one nonlinearbeamcolumn element with fiber section for the column and one zerolenght fiber section element (steel and concrete unconfined and confined). The model does not run.


In my second test I have used a nonlinearbeamcolumn element for the column and a nonlinear beam column element very short (500mm diametr of section and 50mm height of the element) with only two integration section at the base.

In my third test I have used a nonlinear beam column element for the column and two short nonlinearbeamcolumn element with only two integration section for element.

The third case shows a better distribution of the deformations


The model runs but I have a doubt about the reliability and accuracy of the results.


Thanks

Aizen

Dear fmk

Thanks for the help.

My problem is particular.

I have to simulate a concentrated damage at the base of a r.c. column. The damage is concentrated at one section.
This section has rebars less resistent than ones of the upper portion of the element (in this section some connections have been placed, the rebars of the anchorages are weaker than the longitudinal bars used in the upper part of the element ).

I have applied a horizontal cyclic load at the top of the column. The section less resistent at the base of the element, has greater demands (trend of moment for the particular load patter) and being less resistant, it will be deformed more (greater rotations).

The fiber model has been built using one element at the base (short element 0.1m - 0.2m) and one element (long element 1.5m) for the upper part of the column.

The base section is "like a hinge" and so the upper part of the model must rotate as a rigid body and so there are minor deformations of the longitudinal rebars of the upper sections.

So I want to simulate a fiber section at the base where deformations of the longitudinal rebars concentrate. I want simulate that deformations of the longitudinal bar at the base section are greater than ones of the section of the upper element.

So is it correct using a such short element at the base?

Why does not a zerolenght fiber element work in this case?

If i use a zerolenght fiber element in this case (section at the base less resistent of the upper section) the analysis does not run correctly and stops at first (after a few short cycles)

thanks

aizen

Is it possible to remove a patch ( for ex. circular ring )of section fiber using the remove command at the end of a analysis and then continue with another analisys?