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thanks for your care.It was great of you.

I want to model Triple Friction Pendulum Element in opensees. i have downloaded TPB examples from this link:
https://dl.dropboxusercontent.com/u/214 ... tation.rar
when I run it on opensees this error comes up:

OpenSees > source CheckingTripleFrictionPendulum_1DDynamics_ConstFriction.tcl
TripleFrictionPendulum element v2.0.0 - Written by Nhan@unr
OPS_GetIntInput -- error reading 5
WARNING invalid element dataTclElementCommand -- unable to create element of typ
e : TripleFrictionPendulum
expected integer but got "0.36"
I'm using the opensees 2.4.6 and make no change to the model.

Hi everybody.i have a very simple 3-d concrete frame.when i perform gravity analysis this message comes up.what is it and how can i solve it?
OpenSees > source 33.tcl
WARNING: CTestEnergyIncr::test() - failed to converge
after: 6 iterations
NewtnRaphson::solveCurrentStep() -the ConvergenceTest object failed in test()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 7 with domain at
load factor 0.8
OpenSees > analyze failed, returned: -3 error flag

here is the code:
wipe
model basicBuilder -ndm 3 -ndf 6


#Nodal coordinates:
node 1 0 0 0
node 2 0 3.2 0
node 3 5 0 0
node 4 5 3.2 0
node 5 0 0 5
node 6 0 3.2 5
node 7 5 0 5
node 8 5 3.2 5
node 9 2.5 3.2 2.5;

#Bondary condition:
fix 1 1 1 1 1 1 1
fix 3 1 1 1 1 1 1
fix 5 1 1 1 1 1 1
fix 7 1 1 1 1 1 1;


#Assgine rigid diaphragm:
rigidDiaphragm 2 9 2 4 6 8

#Coinstraint rigid diaphragm
fix 9 0 1 0 1 0 1

#assine masses:
mass 2 670 670 670 0 0 0
mass 4 670 670 670 0 0 0
mass 6 670 670 670 0 0 0
mass 8 670 670 670 0 0 0;

#Define materials:
# MATERIAL parameters -------------------------------------------------------------------
set IDconcU 1; # material ID tag -- unconfined cover concrete
set IDreinf 2; # material ID tag -- reinforcement
# nominal concrete compressive strength
set fc -2100000; # CONCRETE Compressive Strength, ksi (+Tension, -Compression)
set Ec 2.18e+09; # Concrete Elastic Modulus
# unconfined concrete
set fc1U $fc; # UNCONFINED concrete (todeschini parabolic model), maximum stress
set eps1U -0.003; # strain at maximum strength of unconfined concrete
set fc2U [expr 0.25*$fc1U]; # ultimate stress
set eps2U -0.0065; # strain at ultimate stress
set lambda 0.1; # ratio between unloading slope at $eps2 and initial slope $Ec
# tensile-strength properties
set ftU [expr -0.1*$fc1U]; # tensile strength +tension
set Ets [expr $ftU/0.002]; # tension softening stiffness
# -----------
set Fy 40000000; # STEEL yield stress
set Es 2.1e+10; # modulus of steel
set Bs 0.01; # strain-hardening ratio
set R0 18; # control the transition from elastic to plastic branches
set cR1 0.925; # control the transition from elastic to plastic branches
set cR2 0.15; # control the transition from elastic to plastic branches
#uniaxialMaterial Concrete01 $IDconcU $fc1U $eps1U $fc2U $eps2U ; # build cover concrete (unconfined)
uniaxialMaterial Concrete02 $IDconcU $fc1U $eps1U $fc2U $eps2U $lambda $ftU $Ets;
uniaxialMaterial Steel02 $IDreinf $Fy $Es $Bs $R0 $cR1 $cR2;


#Define sections:
set 50.50-8T20 1;
set B45.45-1 2;

section fiberSec 1 {
patch quadr $IDconcU 5 5 -0.25 -0.25 0.25 -0.25 0.25 0.25 -0.25 0.25
layer straight $IDreinf 3 0.00031416 -0.19 -0.19 0.19 -0.19 ; #Bot layer
layer straight $IDreinf 3 0.00031416 -0.19 0.19 0.19 0.19 ; #top layer
fiber 0.19 0 0.00031416 $IDreinf ; #right layer
fiber -0.19 0 0.00031416 $IDreinf ; #left layer
}; #end of definition of C50.50-8T20

section fiberSec 2 {
patch quadr $IDconcU 5 5 -0.225 -0.225 0.225 -0.225 0.225 0.225 -0.225 0.225
layer straight $IDreinf 3 0.00031416 -0.165 -0.165 0.165 -0.165 ; #Bot layer
layer straight $IDreinf 4 0.0003801 -0.164 0.164 0.164 0.164 ; #top layer
}; #end of definition of B45.45-1-TOP 4n22 & bot 3n20

#Assign torsional stiffness for 3D Model:
uniaxialMaterial Elastic 10 1000000000;
section Aggregator 20 10 T -section 1
section Aggregator 21 10 T -section 2

# Geometric transformation for columns

geomTransf Linear 1 0 0 1 ; #columns

geomTransf Linear 2 0 0 1 ; #XZ beams

geomTransf Linear 3 1 0 0 ; #YZ plane beams



#Define elements:
#columnSections:
element nonlinearBeamColumn 1 1 2 5 20 1
element nonlinearBeamColumn 2 3 4 5 20 1
element nonlinearBeamColumn 3 5 6 5 20 1
element nonlinearBeamColumn 4 7 8 5 20 1;

#Beamsections:
element nonlinearBeamColumn 5 2 4 5 21 2
element nonlinearBeamColumn 6 6 8 5 21 2
element nonlinearBeamColumn 7 2 6 5 21 3
element nonlinearBeamColumn 8 4 8 5 21 3;

#Define Gravity loads:
pattern Plain 1 Linear {
eleLoad -ele 5 6 7 8 -type -beamUniform 0 -5000

};

# Gravity-analysis parameters -- load-controlled static analysis
set Tol 1.0e-8; # convergence tolerance for test
constraints Lagrange; # 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
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
this is my first time that i model 3-d frame with opensees.Please help me with this one.
Regards

i use global and local force recorder in order to get element forces after pushover analysis, but the axial force of beams isn't zero.Does any body knows what goes wrong?

Hi.I have the same problem.I have a 7-story concrete frame(2D) and i want to do pushover analysis but whatever i do i face convergence problems . i've tested different analysis parameters and i have changed # of steps and it hasn't worked yet.and i have used FBE and DBE elements and both have convergence problems.Could you please help me with this one?

Hi everyone.
i want to model rebar by the use of hystertic material , but unfotunately i have little information about this kind of material.i don't know how to calculate pinchX or another parameters.can you help me and introduce an article about it?

vesna wrote:
> basicForces are forces at element ends (nodes i and j) that corresponds to
> basic degrees of freedom (e.g., if in 2D these are axial force at node j,
> moment at node i, and moment at node j).
>
> basicDermation are deformation that correspond to basic degrees of freedom
> (e.g., if in 2D these are axial displacement at node j, rotation at node i,
> and rotation at node j).
>
> plasticDermation are plastic deformation of an element (e.g., if in 2D
> these are plastic axial displacement at node j, plastic rotation at node i,
> and plastic rotation at node j).
what if i want to use recorder for another station in an element(for example basic deformation at L/4 of a column or beam)? shall i use another point (and element) there?
thanks

Thanks dear vesna.
The target displacement was too large for a 2-story frame and all models converged up to 27cm.
Now i have another problem.i modeled the frame using BeamwithHinges,nonlinearBeamcolumn and dispBeamColumn . when i plot their pushover there is a slight diffrence between the first and second one, but i faced a very big difference in latter(it overestimates the capacity of the frame).it's so different as if it's another structure!i've studied the difference between force-based and displacement-based elements,but i don't think that difference is reasonable.
could you please help me vesna? is it rational?

Hi everybody.I have the same problem.
I have a 2D model with fiber section and displacement-based element and I want perform a pushover analysis , but I face this error.Do you know what goes wrong?
OpenSees > source Untitled1.tcl
Model Built
WARNING: CTestEnergyIncr::test() - failed to converge
after: 6 iterations
NewtnRaphson::solveCurrentStep() -the ConvergenceTest object failed in test()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at
load factor 9.3315
OpenSees > analyze failed, returned: -3 error flag
WARNING: CTestEnergyIncr::test() - failed to converge
after: 6 iterations
NewtnRaphson::solveCurrentStep() -the ConvergenceTest object failed in test()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at
load factor 9.3315
OpenSees > analyze failed, returned: -3 error flag
Trying Newton with Initial Tangent ..
WARNING - ForceBeamColumn2d::update - failed to get compatible element forces &
deformations for element: 6(dW: << 1.00652e-011)
Domain::update - domain failed in update
DisplacementControl::update - model failed to update for new dU
WARNING NewtonRaphson::solveCurrentStep() -the Integrator failed in update()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at
load factor 781.173
OpenSees > analyze failed, returned: -3 error flag
Trying Broyden ..
WARNING: CTestEnergyIncr::test() - failed to converge
after: 10 iterations
WARNING: CTestEnergyIncr::test() - failed to converge
after: 10 iterations
WARNING: CTestEnergyIncr::test() - failed to converge
after: 10 iterations
WARNING: CTestEnergyIncr::test() - failed to converge
after: 10 iterations
WARNING: CTestEnergyIncr::test() - failed to converge
after: 10 iterations
WARNING: CTestEnergyIncr::test() - failed to converge
after: 10 iterations
WARNING: CTestEnergyIncr::test() - failed to converge
after: 6 iterations
Broyden::solveCurrentStep() -the ConvergenceTest object failed in test()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at
load factor 2.85113
OpenSees > analyze failed, returned: -3 error flag
Trying NewtonWithLineSearch ..
WARNING: CTestEnergyIncr::test() - failed to converge
after: 6 iterations
NewtonLineSearch::solveCurrentStep() -the ConvergenceTest object failed in test(
)
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at
load factor 9.3315
OpenSees > analyze failed, returned: -3 error flag
DonePushover