I have modelled a rectangular column element with fiber section (column height is 2m) and 'forceBeamColumn' element (shown below). At the time of dynamic analysis it shows error mentioned below but i have analysed same model with 'elasticBeamColumn' element it runs smoothly without any error.
## Sample Code (creating column elements)
# Define materials for nonlinear columns
# ------------------------------------------
# CONCRETE tag f'c ec0 f'cu ecu
# Core concrete (confined)
uniaxialMaterial Concrete01 1 -40.0e6 -0.004 -30.0e6 -0.02
# Cover concrete (unconfined)
uniaxialMaterial Concrete01 2 -40.0e6 -0.004 0.0 -0.006
# STEEL
# Reinforcing steel
set fy [expr 1.25*415e6]; # Yield stress
set Es 200e9; # Young's modulus
set dia 25e-3; # Diameter of the Reinforcing bar
set steelTagCol 3;
# tag fy E0 b
uniaxialMaterial Steel01 $steelTagCol $fy $Es $dia
# Define cross-section for nonlinear columns
# set some paramaters
set colWidth 0.5;
set colDepth 0.5;
set pi [expr 2.0*asin(1.0)];
set cover 0.05;
set d 0.025;
set As [expr ($pi/4)*(pow($d,2))]; ; # area of no. 1 bars
## C/S properties
set Mu 0.15; # Poisson's Ratio of concrete
set Ec 30e9; # Modulus of elasticity of concrete
set A_Col [expr $colWidth*$colDepth]; # Area of the Girder section
set IzC [expr ($colWidth*pow($colDepth,3))/12]; # MOI of the Girder section w.r.t. local Z axis
set IyC [expr ($colDepth*pow($colWidth,3))/12]; # MOI of the Girder section w.r.t. local Y axis
set JC [expr $colDepth*pow($colWidth,3)*((1/3)-(0.21*($colWidth/$colDepth)*(1-(pow($colWidth,4)/(pow($colDepth,4)*12)))))]; # Torsional MOI of rectangular section
set GC [expr ($Ec/(2*(1+$Mu)))]; # Shear Modulas of the section
set secIDCol 1; # section tag for section fibre
# some variables derived from the parameters
set y1 [expr $colDepth/2.0]
set z1 [expr $colWidth/2.0]
section Fiber $secIDCol -GJ [expr $GC*$JC] {
# Create the concrete core fibers
patch rect 1 10 10 [expr $cover-$y1] [expr $cover-$z1] [expr $y1-$cover] [expr $z1-$cover]
# Create the concrete cover fibers (top, bottom, left, right)
patch rect 2 10 5 [expr -$y1] [expr $z1-$cover] $y1 $z1
patch rect 2 10 5 [expr -$y1] [expr -$z1] $y1 [expr $cover-$z1]
patch rect 2 5 1 [expr -$y1] [expr $cover-$z1] [expr $cover-$y1] [expr $z1-$cover]
patch rect 2 5 1 [expr $y1-$cover] [expr $cover-$z1] $y1 [expr $z1-$cover]
# Create the reinforcing fibers (left, middle, right)
layer straight 3 3 $As [expr $y1-$cover] [expr $z1-$cover] [expr $y1-$cover] [expr $cover-$z1]
layer straight 3 2 $As 0.0 [expr $z1-$cover] 0.0 [expr $cover-$z1]
layer straight 3 3 $As [expr $cover-$y1] [expr $z1-$cover] [expr $cover-$y1] [expr $cover-$z1]
}
# set up geometric transformation of element
#set LinTransf 1;
set ColTransfTag 1;
geomTransf PDelta $ColTransfTag 0 0 1; # PDelta Transformation
# Setup Plastic hinge Properties
set Lpi 0.35; # Length of plastic Hinge at 'ith' end.
set Lpj 0.35; # Length of plastic hinge at 'jth' end.
set intgrPts 6;
# Define Column elements
set iColumn ""
set N0col [expr 10000]; # column element numbers
set level 0
for {set frame 1} {$frame <=[expr $NFrame]} {incr frame 1} {
for {set level 1} {$level <= [expr $ReqdFloors-1]} {incr level 1} {
for {set pier 1} {$pier <= [expr $NBayZ+1]} {incr pier 1} {
set elemID [expr $N0col +$level*$Dlevel + $frame*$Dframe+$pier]
set NodeI [expr $level*$Dlevel + $frame*$Dframe+$pier]
set NodeJ [expr ($level+1)*$Dlevel + $frame*$Dframe+$pier]
#element nonlinearBeamColumn $elemID $NodeI $NodeJ $intgrPts $secIDCol $ColTransfTag -intregation Legendre; # columns
element forceBeamColumn $elemID $NodeI $NodeJ $ColTransfTag HingeRadau $secIDCol $Lpi $secIDCol $Lpj $secIDCol;
#element forceBeamColumn $elemID $NodeI $NodeJ $intgrPts $secIDCol $ColTransfTag;
#element elasticBeamColumn $elemID $NodeI $NodeJ $A_Col $Ec $GC $JC $IyC $IzC $ColTransfTag;
}
}
}
##########....................################..................###############
The above 4 types of elements I have tried for column element.
## warnings and errors
WARNING - ForceBeamColumn3d::update - failed to get compatible element forces & deformations for element: 20501(dW: << 0.0104173, dW0: 30936)
WARNING - ForceBeamColumn3d::update - failed to get compatible element forces & deformations for element: 20601(dW: << 0.0083161, dW0: 48321.2)
WARNING - ForceBeamColumn3d::update - failed to get compatible element forces & deformations for element: 20604(dW: << 0.000708733, dW0: 536217)
WARNING - ForceBeamColumn3d::update - failed to get compatible element forces & deformations for element: 30603(dW: << 0.000124699, dW0: 44481.4)
Domain::update - domain failed in update
Newmark::update() - failed to update the domain
WARNING AcceleratedNewton::solveCurrentStep() -the Integrator failed in update()
DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 2.915
OpenSees > analyze failed, returned: -3 error flag
WARNING - ForceBeamColumn3d::update - failed to get compatible element forces & deformations for element: 20603(dW: << -0.00284286, dW0: 1.84258e+06)
Domain::update - domain failed in update
Newmark::update() - failed to update the domain
WARNING ModifiedNewton::solveCurrentStep() -the Integrator failed in update()
DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 2.915
OpenSees > analyze failed, returned: -3 error flag
Trying Newton with Initial Tangent ..
WARNING: CTestNormDispIncr::test() - failed to converge
after: 10000 iterations current Norm: 0.0153696 (max: 1e-06, Norm deltaR: 220884)
NewtnRaphson::solveCurrentStep() -the ConvergenceTest object failed in test()
DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 2.915
OpenSees > analyze failed, returned: -3 error flag
Trying Broyden ..
WARNING: CTestEnergyIncr::test() - failed to converge
after: 10 iterations
current EnergyIncr: 152.941 (max: 1e-06) Norm deltaX: 0.00521755, Norm deltaR: 706612
WARNING - ForceBeamColumn3d::update - failed to get compatible element forces & deformations for element: 20601(dW: << 207490, dW0: -323156)
WARNING - ForceBeamColumn3d::update - failed to get compatible element forces & deformations for element: 20603(dW: << 3.22026e+06, dW0: -323007)
Domain::update - domain failed in update
Newmark::update() - failed to update the domain
WARNING ModifiedNewton::solveCurrentStep() -the Integrator failed in update()
DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 2.9175
OpenSees > analyze failed, returned: -3 error flag
####.......................#############......................########
and after few time steps analysis failed. please help with this issue why this is happening and how to rectify it??
Thank You