simply supported beam for pushover analysis

[aahashib]

Hi!

I have tried to model a simply supported beam for pushover analysis. I am facing 3 problems. If anyone could help me solve these 3 problems, I would be really grateful. Thanks.

1. in actual test they applied loads in two points. how can i apply pushover loads in two nodes?

# Pushover Analysis for a Single-Column
# RC Circular Columns
# Abdullah Al Hashib
# Dec. 20, 2015
#
# ^Y
# |------------------------- -> X
# 1 (1) LBeam 2
#
# SET UP ----------------------------------------------------------------------------
# Units: kips, inches, seconds
wipe; # Clear memory of all past model definitions
file mkdir Response3D; # Create data directory
model basic -ndm 2 -ndf 3; # Define the model builder, ndm=#dimension, ndf=#dofs

# Define GEOMETRY ----------------------------------
set LBeam 98.421; # Column length between two rigid links.
set HBeam 11.8; # beam Depth
set BBeam 11.8; # beam Width

# Define ELEMENTS & SECTIONS -----------------------
set BeamSecTag 1; # assign a tag number to the column section
set BeamMidSecTag 2; # without stirrup
set BeamCenterSecTag 3; # coupler region
set ZeroLengthSecTag 4; # assign a tag number to the zerolength element for Bond-Slip
set ZeroLengthSecAggTag 5; # assign a tag number to the zerolength element w/ Bond-Slip but shear stiffness is added

# Define Section Geometry---------------------------
set CovBeam 1.969;
set numBarsBeam 2; # number of longitudinal-reinforcement bars in each side of beam section. (symmetric top & bot)
set barAreaBeam 0.44;
#set barDiaBeam 0.75;
set ABeam [expr $BBeam*$HBeam];

# nodal coordinates----------------------------------
# Node Label X Y Z --->> Height of Structure should be in Y direction <<---
node 1 0. 0. ;
node 2 33.46 0. ;
node 3 46.255 0.;
node 4 52.161 0.;
node 5 64.956 0.;
node 6 98.421 0.;

# Nodal constraints -- Boundary Conditions ----
fix 1 1 1 0;
fix 6 0 1 0;

# MATERIAL parameters -------------------------------
set IDconC 1; # material ID tag -- confined core concrete
set IDconcU 2; # material ID tag -- unconfined cover concrete
set IDreinf 3; # material ID tag -- reinforcement
set IDreinfcoupler 4; # material ID tag -- reinforcement with coupler

set IDTotalSlip 9; # material ID tag -- for a bar Bond-Slip effect

# Beam Weight
set Beamweight [expr 0.15*$ABeam*$LBeam/1728]; # Column Self-weight

set g 386.0892; # acceleration of gravity
set mass [expr ($Beamweight*0.4*2)/$g]; # Mass of superstructure
mass 2 $mass $mass $mass; # node#, Mx My Mz, Mass=Weight/g, Consider rotational inertia at nodes
#mass 5 $mass $mass $mass [expr 100*$Weight/$g] [expr 100*$Weight/$g] [expr 100*$Weight/$g]; # node#, Mx My Mz, Mass=Weight/g, Consider rotational inertia at nodes


################################# Concrete ######################################

# nominal concrete compressive strength (by Mander's Model)
set fcu [expr -5.07] ; # CONCRETE Compressive Strength (+Tension, -Compression) for unconfined concrete. Average of Two-Day of Test
set fcc [expr -6.39]; # CONCRETE Compressive Strength (+Tension, -Compression) for confined concrete

# Confined Concrete for core---------------(Combination of Mander's Model and Jeong's Suggested Model)
set fc1UC $fcc; # CONFINED concrete
set eps1UC -0.0046; # strain at maximum strength of confined concrete ccording to mander's model that should be -0.00733
set fc2UC -4.02; # ultimate stress for confined concrete [ Based on mander's model that should be 6.649 ksi (0.85fc1uc)]
set eps2UC -0.023; # strain at ultimate stress according to mander's model that should be -0.025795

# unconfined concrete----------------------(Combination of Mander's Model and Jeong's Suggested Model)
set fc1U $fcu; # UNCONFINED concrete, maximum stress
set eps1U -0.002; # strain at maximum strength of unconfined concrete ccording to the test that should be -0.002805
set fc2U 0.0;
set eps2U -0.005; # strain at ultimate stress; There is an error in concrete02 that I have to increase 0.005 to 0.01

################################ Reinforcement proprety########################
# Mild rebars------------
set Fy 66.5; # STEEL yield stress based AASHTO Guide Spec
set Es 29000.0; # modulus of steel- Average of points
set Fu 95.0;
set Esh [expr 0.043*$Es]; # According to AASHTO Guide Spec
set esh 0.015; # According to AASHTO Guide Spec
set eult 0.1; # According to AASHTO Guide Spec


# Mild Steel Rebars (coupler region)
set Fyc 54.7; # STEEL yield stress of the test specimen
set Esc 60209.69; # modulus of steel
set Fuc 81.2;
set Eshc [expr 2589.02];
set eshc [expr 0.0024];
set eultc 0.043;

uniaxialMaterial Concrete01 $IDconC $fc1UC $eps1UC $fc2UC $eps2UC; # build core concrete (confined)
uniaxialMaterial Concrete01 $IDconcU $fc1U $eps1U $fc2U $eps2U ; # build cover concrete (unconfined)
uniaxialMaterial ReinforcingSteel $IDreinf $Fy $Fu $Es $Esh $esh $eult -GABuck 2. 2. 1. 0.5 -MPCurveParams 0.38 18 4;
#-GABuck 5.92 1. 0.5 0.5 -DMBuck 5.92 1. -CMFatigue 0.26 0.506 0.389 -IsoHard 4.3 0.01 -MPCurveParams 0.333 18 4;

uniaxialMaterial ReinforcingSteel $IDreinfcoupler $Fyc $Fuc $Esc $Eshc $eshc $eultc -GABuck 2. 2. 1. 0.5 -MPCurveParams 0.38 18 4; # build reinforcement with coupler

########################## Reinforcement including Total Slip ############################
### Total bar slip is a series of duct slip, bar slip, and bar elongation
### See Excel file called "Bond-Slip Effect on Reinforcement Stress-Strain" for updated properties
set Fyb $Fy; # Updated STEEL yield stress including bond-slip effect
set Esb 14756.31; # Updated modulus of steel including bond-slip effect, 24881
set Fub $Fu; # Updated Ultimate Strength including bond-slip effect
set Eshb 1239.; # Updated Strain Hardening Stiffness including bond-slip effect
set eshb 0.017; # Updated Strain @ Strain Hardening including bond-slip effect, for convergancy, I had to reduce it
set eultb 0.103; # Updated Ultimate Strain including bond-slip effect

#uniaxialMaterial Steel02 $IDTotalSlip $Fyb $Esb $Bsb $R0b $cR1b $cR2b 0.0 0.05 0. 1.0 0.; # build mild reinforcement material
uniaxialMaterial ReinforcingSteel $IDTotalSlip $Fyb $Fub $Esb $Eshb $eshb $eultb -GABuck 2. 2. 1. 0.5 -MPCurveParams 0.38 18 4;
#-GABuck 2.0 2. 1. 0.5 -DMBuck 5.92 1. -CMFatigue 0.26 0.506 0.389 -IsoHard 4.3 0.01 -MPCurveParams 0.38 18 4;

# FIBER SECTION properties -------------------------------------------------------------
# symmetric section
# y
# ^
# |
# --------------------- -- --
# | o o o | | -- cover
# | | |
# | | |
# z <--- | + | H
# | | |
# | | |
# | o o o | | -- cover
# --------------------- -- --
# |-------- B --------|
#
# Rectangular Fiber RC section for Beam------------------

set numBarsIntBeam 0; # TOTAL number of reinforcing bars on the intermediate layers
set barAreaIntBeam $barAreaBeam; # longitudinal-reinforcement bar area
set nfCoreY 50; # number of fibers in the core patch in the y direction
set nfCoreZ 50; # number of fibers in the core patch in the z direction
set nfCoverY 50; # number of fibers in the cover patches with long sides in the y direction
set nfCoverZ 50; # number of fibers in the cover patches with long sides in the z direction
# rectangular section with one layer of steel at top and bottom and a confined core.
source BuildRCrectSection.tcl; # procedure for definining RC fiber section
# BuildRCrectSection $RecColSecTag $HBeam $BBeam $CoverH $CoverB $coreID $coverID $steelID $numBarsTopBeam $barAreaTopBeam $numBarsBotBeam $barAreaBotBeam $numBarsIntBeam $barAreaIntBeam $nfCoreY $nfCoreZ $nfCoverY $nfCoverZ;
BuildRCrectSection $BeamSecTag $HBeam $BBeam $CovBeam $CovBeam $IDconC $IDconcU $IDreinf $numBarsBeam $barAreaBeam $numBarsBeam $barAreaBeam $numBarsIntBeam $barAreaIntBeam $nfCoreY $nfCoreZ $nfCoverY $nfCoverZ;

source BuildRCrectSection.tcl; # procedure for definining RC fiber section
# BuildRCrectSection $RecColSecTag $HBeam $BBeam $CoverH $CoverB $coreID $coverID $steelID $numBarsTopBeam $barAreaTopBeam $numBarsBotBeam $barAreaBotBeam $numBarsIntBeam $barAreaIntBeam $nfCoreY $nfCoreZ $nfCoverY $nfCoverZ;
BuildRCrectSection $BeamMidSecTag $HBeam $BBeam $CovBeam $CovBeam $IDconcU $IDconcU $IDreinf $numBarsBeam $barAreaBeam $numBarsBeam $barAreaBeam $numBarsIntBeam $barAreaIntBeam $nfCoreY $nfCoreZ $nfCoverY $nfCoverZ;

source BuildRCrectSection.tcl; # procedure for definining RC fiber section
# BuildRCrectSection $RecColSecTag $HBeam $BBeam $CoverH $CoverB $coreID $coverID $steelID $numBarsTopBeam $barAreaTopBeam $numBarsBotBeam $barAreaBotBeam $numBarsIntBeam $barAreaIntBeam $nfCoreY $nfCoreZ $nfCoverY $nfCoverZ;
BuildRCrectSection $BeamCenterSecTag $HBeam $BBeam $CovBeam $CovBeam $IDconcU $IDconcU $IDreinfcoupler $numBarsBeam $barAreaBeam $numBarsBeam $barAreaBeam $numBarsIntBeam $barAreaIntBeam $nfCoreY $nfCoreZ $nfCoverY $nfCoverZ;

source BuildRCrectSection.tcl; # procedure for definining RC fiber section
# BuildRCrectSection $RecColSecTag $HBeam $BBeam $CoverH $CoverB $coreID $coverID $steelID $numBarsTopBeam $barAreaTopBeam $numBarsBotBeam $barAreaBotBeam $numBarsIntBeam $barAreaIntBeam $nfCoreY $nfCoreZ $nfCoverY $nfCoverZ;
BuildRCrectSection $ZeroLengthSecTag $HBeam $BBeam $CovBeam $CovBeam $IDconC $IDconcU $IDTotalSlip $numBarsBeam $barAreaBeam $numBarsBeam $barAreaBeam $numBarsIntBeam $barAreaIntBeam $nfCoreY $nfCoreZ $nfCoverY $nfCoverZ;

#section fiberSec $BeamSecTag {;
# # end of fibersection definition

# define geometric transformation: performs a linear geometric transformation of beam stiffness and resisting force from the basic system to the global-coordinate system
set BeamTransfTag 1; # associate a tag to column transformation
set BeamMidTransfTag 2; # associate a tag to column transformation
set BeamCenterTransfTag 3; # associate a tag to column transformation

set BeamTransfType Linear; # options, Linear PDelta Corotational
#geomTransf $BeamTransfType $BeamTransfTag 0 0 1 -jntOffset 1 0 0 1 0 0
geomTransf $BeamTransfType $BeamTransfTag;
geomTransf $BeamTransfType $BeamMidTransfTag;
geomTransf $BeamTransfType $BeamCenterTransfTag;


# calculated geometry parameters---------------------
#set ABeam [expr $DCol*$DCol*3.14*.25]; # cross-sectional area of Column
set IzBeam [expr 1.0/12.0*$BBeam*pow($HBeam,3.0)]; # Column moment of inertia
set Ec [expr 0.47*1802.5*pow( -$fcu ,0.5)]; # 0.2 of Concrete Elastic Modulus----->>> Take 0.1, 0.2 and 0.47
set G [expr $Ec/(2.*(1.+0.2))];
set J [expr $IzBeam*2];
#set lpi [expr 1.0*20.04]; # Plastic hinge Length based on Priestley et al. (Primary Lp=18.66 in)

# Linear elastic properties of column which should be used in zeroLength element
uniaxialMaterial Elastic 50 [expr $Ec*$ABeam]; # EA: Axial Regidity
uniaxialMaterial Elastic 60 [expr $G*$ABeam]; # GA: Shear Rigidity
uniaxialMaterial Elastic 80 [expr $G*$J]; # GJ: Torsional Rigidity

#section Aggregator $ZeroLengthSecAggTag 60 Vy 60 Vz 80 T -section $ZeroLengthSecTag; # To aggregate Section with modified reinforcement to incude bond-slip

section Aggregator $ZeroLengthSecAggTag 50 P 60 Vy 80 T -section $ZeroLengthSecTag; # To aggregate Section with modified reinforcement to incude bond-slip

# element connectivity:
set numIntgrPts 5; # number of integration points for force-based element
element forceBeamColumn 1 1 2 $numIntgrPts -sections $ZeroLengthSecAggTag $BeamSecTag $BeamSecTag $BeamSecTag $BeamSecTag $BeamTransfTag;
element forceBeamColumn 2 2 3 $numIntgrPts -sections $BeamMidSecTag $BeamMidSecTag $BeamMidSecTag $BeamMidSecTag $BeamMidSecTag $BeamMidTransfTag;
element forceBeamColumn 3 3 4 $numIntgrPts -sections $BeamCenterSecTag $BeamCenterSecTag $BeamCenterSecTag $BeamCenterSecTag $BeamCenterSecTag $BeamCenterTransfTag;
element forceBeamColumn 4 4 5 $numIntgrPts -sections $BeamMidSecTag $BeamMidSecTag $BeamMidSecTag $BeamMidSecTag $BeamMidSecTag $BeamMidTransfTag;
element forceBeamColumn 5 5 6 $numIntgrPts -sections $BeamSecTag $BeamSecTag $BeamSecTag $BeamSecTag $ZeroLengthSecAggTag $BeamTransfTag;

# Define RECORDERS -------------------------------------------------------------
#recorder Node -file Response3D/DFree.out -time -node 2 -dof 1 2 3 disp; # displacements of free nodes
recorder Node -file Response3D/DNode3.out -time -node 3 -dof 1 2 3 disp; # displacements of free nodes
recorder Node -file Response3D/DNode4.out -time -node 4 -dof 1 2 3 disp; # displacements of free nodes
recorder Node -file Response3D/RNode1.out -time -node 1 -dof 1 2 3 reaction; # support reaction
recorder Node -file Response3D/RNode6.out -time -node 6 -dof 1 2 3 reaction; # support reaction


# define GRAVITY -------------------------------------------------------------
puts " Total Dead Load= $Beamweight"
set Wy [expr $Beamweight/$LBeam];
pattern Plain 1 Linear {;
eleLoad -ele 1 -type -beamUniform -$Wy; # distributed self-weight on beam
eleLoad -ele 2 -type -beamUniform -$Wy; # distributed self-weight on beam
eleLoad -ele 3 -type -beamUniform -$Wy; # distributed self-weight on beam
eleLoad -ele 4 -type -beamUniform -$Wy; # distributed self-weight on beam
eleLoad -ele 5 -type -beamUniform -$Wy; # distributed self-weight on beam
# load 3 0. -0.001 0.
#
};

# Gravity-analysis parameters -- load-controlled static analysis
set Tol 1.0e-8; # convergence tolerance for test
constraints Plain; # how it handles boundary conditions
numberer Plain; # 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 NormDispIncr $Tol 15; # determine if convergence has been achieved at the end of an iteration step
algorithm Newton; # use Newton's solution algorithm: updates tangent stiffness at every iteration
set NstepGravity 10; # apply gravity in 10 steps
set DGravity [expr 1./$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
puts " Gravity Analysis is done!"

set omega2 [eigen 1];
set omega1 [expr pow($omega2 ,0.5)];
set period1 [expr 2*3.1415/$omega1];
puts " OpenSees Calculated Period of First mode= $period1"

# we need to set up parameters that are particular to the model.
set IDctrlNode 3; # node where displacement is read for displacement control
set IDctrlDOF 2; # degree of freedom of displacement read for displacement contro

#set iDmax "0.01 0.017 0.03 0.045";
set iDmax 0.02; # Only for Push <<<<<------ Consider + - to have pushover in the both side. Run it with one then use Matlab file to plot one side, Run it again with other sign and add new graph in Matlab

set Dincr [expr 0.00001*$LBeam]; # displacement increment for pushover. you want this to be very small, but not too small to slow down the analysis
set Fact [expr $LBeam]; # scale drift ratio by storey height for displacement cycles
set CycleType Push; # <<<<<----- you can do Full / Push / HalfCycle with the proc
set Ncycles 1; # specify the number of cycles at each peak

# create load pattern for lateral pushover load
set Hload [expr $Beamweight/20.]; # define the lateral load as a proportion of the weight so that the pseudo time equals the lateral-load coefficient when using linear load pattern
set iPushNode 2; # define nodes where lateral load is applied in static lateral analysis

pattern Plain 200 Linear {; # define load pattern -- generalized
foreach PushNode $iPushNode {
load $PushNode 0.0 -$Hload 0.0
}
}
variable constraintsTypeStatic Plain; # default;
if { [info exists RigidDiaphragm] == 1} {
if {$RigidDiaphragm=="ON"} {
variable constraintsTypeStatic Lagrange; # for large model, try Transformation
}; # if rigid diaphragm is on
}; # if rigid diaphragm exists
constraints $constraintsTypeStatic

set numbererTypeStatic RCM
numberer $numbererTypeStatic

set systemTypeStatic BandGeneral; # try UmfPack for large model
system $systemTypeStatic

variable TolStatic 1.e-8; # Convergence Test: tolerance
variable maxNumIterStatic 6; # Convergence Test: maximum number of iterations that will be performed before "failure to converge" is returned
variable printFlagStatic 0; # Convergence Test: flag used to print information on convergence (optional) # 1: print information on each step;
variable testTypeStatic EnergyIncr ; # Convergence-test type
test $testTypeStatic $TolStatic $maxNumIterStatic $printFlagStatic;
# for improved-convergence procedure:
variable maxNumIterConvergeStatic 2000;
variable printFlagConvergeStatic 0;

variable algorithmTypeStatic Newton
algorithm $algorithmTypeStatic;

integrator DisplacementControl $IDctrlNode $IDctrlDOF $Dincr

set analysisTypeStatic Static
analysis $analysisTypeStatic

# --------------------------------- perform Static Cyclic Displacements Analysis

proc GeneratePeaks {Dmax {DincrStatic 0.001} {CycleType "Full"} {Fact 1} } {; # generate incremental disps for Dmax
###########################################################################
## GeneratePeaks $Dmax $DincrStatic $CycleType $Fact
###########################################################################
# generate incremental disps for Dmax
# this proc creates a file which defines a vector then executes the file to return the vector of disp. increments
# by Silvia Mazzoni, 2006
# input variables
# $Dmax : peak displacement (can be + or negative)
# $DincrStatic : displacement increment (optional, default=0.01, independently of units)
# $CycleType : Full (0->+peak), Half (0->+peak->0), Full (0->+peak->0->-peak->0) (optional, def=Full)
# $Fact : scaling factor (optional, default=1)
# $iDstepFileName : file name where displacement history is stored temporarily, until next disp. peak
# output variable
# $iDstep : vector of displacement increments
file mkdir data
set outFileID [open data/tmpDsteps.tcl w]
set Disp 0.
puts $outFileID "set iDstep { ";puts $outFileID $Disp;puts $outFileID $Disp; # open vector definition and some 0
set Dmax [expr $Dmax*$Fact]; # scale value
if {$Dmax<0} {; # avoid the divide by zero
set dx [expr -$DincrStatic]
} else {
set dx $DincrStatic;
}
set NstepsPeak [expr int(abs($Dmax)/$DincrStatic)]
for {set i 1} {$i <= $NstepsPeak} {incr i 1} {; # zero to one
set Disp [expr $Disp + $dx]
puts $outFileID $Disp; # write to file
}
if {$CycleType !="Push"} {
for {set i 1} {$i <= $NstepsPeak} {incr i 1} {; # one to zero
set Disp [expr $Disp - $dx]
puts $outFileID $Disp; # write to file
}
if {$CycleType !="HalfCycles"} {
for {set i 1} {$i <= $NstepsPeak} {incr i 1} {; # zero to minus one
set Disp [expr $Disp - $dx]
puts $outFileID $Disp; # write to file
}
for {set i 1} {$i <= $NstepsPeak} {incr i 1} {; # minus one to zero
set Disp [expr $Disp + $dx]
puts $outFileID $Disp; # write to file
}
}
}
#puts "i=$i"; puts "Dips=$Disp"
puts $outFileID " }"; # close vector definition
close $outFileID
source data/tmpDsteps.tcl; # source tcl file to define entire vector
return $iDstep
}

set fmt1 "%s Cyclic analysis: CtrlNode %.3i, dof %.1i, Disp=%.4f %s"; # format for screen/file output of DONE/PROBLEM analysis
foreach Dmax $iDmax {
set iDstep [GeneratePeaks $Dmax $Dincr $CycleType $Fact]; # this proc is defined above
for {set i 1} {$i <= $Ncycles} {incr i 1} {
set zeroD 0
set D0 0.0
foreach Dstep $iDstep {
set D1 $Dstep
set Dincr [expr $D1 - $D0]
integrator DisplacementControl $IDctrlNode $IDctrlDOF $Dincr
analysis Static
# ----------------------------------------------first analyze command------------------------
set ok [analyze 1]
# ----------------------------------------------if convergence failure-------------------------
if {$ok != 0} {
# if analysis fails, we try some other stuff
# performance is slower inside this loop global maxNumIterStatic; # max no. of iterations performed before "failure to converge" is ret'd
if {$ok != 0} {
puts "Trying Newton with Initial Tangent .."
test NormDispIncr $Tol 2000 0
algorithm Newton -initial
set ok [analyze 1]
test $testTypeStatic $TolStatic $maxNumIterStatic 0
algorithm $algorithmTypeStatic
}
if {$ok != 0} {
puts "Trying Broyden .."
algorithm Broyden 8
set ok [analyze 1 ]
algorithm $algorithmTypeStatic
}
if {$ok != 0} {
puts "Trying NewtonWithLineSearch .."
algorithm NewtonLineSearch 0.8
set ok [analyze 1]
algorithm $algorithmTypeStatic
}
if {$ok != 0} {
set putout [format $fmt1 "PROBLEM" $IDctrlNode $IDctrlDOF [nodeDisp $IDctrlNode $IDctrlDOF] $LunitTXT]
puts $putout
return -1
}; # end if
}; # end if
# -----------------------------------------------------------------------------------------------------
set D0 $D1; # move to next step
}; # end Dstep
}; # end i
}; # end of iDmaxCycl
# -----------------------------------------------------------------------------------------------------
set LunitTXT inch
if {$ok != 0 } {
puts [format $fmt1 "PROBLEM" $IDctrlNode $IDctrlDOF [nodeDisp $IDctrlNode $IDctrlDOF] $LunitTXT]
} else {
puts [format $fmt1 "DONE" $IDctrlNode $IDctrlDOF [nodeDisp $IDctrlNode $IDctrlDOF] $LunitTXT]
}






2. in actual test, it seems like they used roller in two end supports. But i used hing in one end and roller in other. will that affect pushover analysis? because if i use two rollers, then it shows error.

3. there are some warnings like below. are they big issue in getting the result?

Starting OpenSees..


OpenSees -- Open System For Earthquake Engineering Simulation
Pacific Earthquake Engineering Research Center -- 2.4.6 (rev 6062)

(c) Copyright 1999-2013 The Regents of the University of California
All Rights Reserved
(Copyright and Disclaimer @ http://www.berkeley.edu/OpenSees/copyright.html)


Total Dead Load= 1.1895954895833332
Gravity Analysis is done!
OpenSees Calculated Period of First mode= 0.029832388967723427
WARNING: CTestEnergyIncr::test() - failed to converge
after: 6 iterations
current EnergyIncr: 0.00808116 (max: 1e-008) Norm deltaX: 0.00158634, Norm deltaR: 51.7678
NewtnRaphson::solveCurrentStep() -the ConvergenceTest object failed in test()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at load factor -445.181
OpenSees > analyze failed, returned: -3 error flag
Trying Newton with Initial Tangent ..
WARNING: CTestEnergyIncr::test() - failed to converge
after: 6 iterations
current EnergyIncr: 5.18211e-007 (max: 1e-008) Norm deltaX: 7.78288e-005, Norm deltaR: 0.170979
NewtnRaphson::solveCurrentStep() -the ConvergenceTest object failed in test()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at load factor -480.409
OpenSees > analyze failed, returned: -3 error flag
Trying Newton with Initial Tangent ..
WARNING: CTestEnergyIncr::test() - failed to converge
after: 6 iterations
current EnergyIncr: 1.38689e-007 (max: 1e-008) Norm deltaX: 2.08136e-005, Norm deltaR: 0.137969
NewtnRaphson::solveCurrentStep() -the ConvergenceTest object failed in test()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at load factor -490.697
OpenSees > analyze failed, returned: -3 error flag
Trying Newton with Initial Tangent ..
WARNING: CTestEnergyIncr::test() - failed to converge
after: 6 iterations
current EnergyIncr: 3.18775e-007 (max: 1e-008) Norm deltaX: 9.21161e-005, Norm deltaR: 0.0721009
NewtnRaphson::solveCurrentStep() -the ConvergenceTest object failed in test()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at load factor -491.158
OpenSees > analyze failed, returned: -3 error flag
Trying Newton with Initial Tangent ..
WARNING: CTestNormDispIncr::test() - failed to converge
after: 2000 iterations current Norm: 2.29329e-008 (max: 1e-008, Norm deltaR: 0.00500837)
NewtnRaphson::solveCurrentStep() -the ConvergenceTest object failed in test()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at load factor -469.409
OpenSees > analyze failed, returned: -3 error flag
Trying Broyden ..
Large trial compressive strain
UniaxialMaterial::setTrial() - material failed in setTrialStrain()
Large trial compressive strain
UniaxialMaterial::setTrial() - material failed in setTrialStrain()
Large trial compressive strain
UniaxialMaterial::setTrial() - material failed in setTrialStrain()
Large trial compressive strain
UniaxialMaterial::setTrial() - material failed in setTrialStrain()
ForceBeamColumn2d::update() - section failed in setTrial
Domain::update - domain failed in update
DisplacementControl::update - model failed to update for new dU
WARNING Broyden::solveCurrentStep() -the Integrator failed in update()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at load factor -491.148
OpenSees > analyze failed, returned: -3 error flag
Trying NewtonWithLineSearch ..
WARNING: CTestEnergyIncr::setEquiSolnAlgo - no SOE
WARNING: CTestEnergyIncr::test() - failed to converge
after: 6 iterations
current EnergyIncr: 2.54379e-005 (max: 1e-008) Norm deltaX: 0.000202774, Norm deltaR: 2.57629
NewtnRaphson::solveCurrentStep() -the ConvergenceTest object failed in test()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at load factor -491.229
OpenSees > analyze failed, returned: -3 error flag
Trying Newton with Initial Tangent ..
WARNING: CTestEnergyIncr::test() - failed to converge
after: 6 iterations
current EnergyIncr: 1.57172e-005 (max: 1e-008) Norm deltaX: 0.000416978, Norm deltaR: 0.765064
NewtnRaphson::solveCurrentStep() -the ConvergenceTest object failed in test()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at load factor -472.099
OpenSees > analyze failed, returned: -3 error flag
Trying Newton with Initial Tangent ..
WARNING: CTestEnergyIncr::test() - failed to converge
after: 6 iterations
current EnergyIncr: 3.36019e-007 (max: 1e-008) Norm deltaX: 2.72089e-005, Norm deltaR: 0.242704
NewtnRaphson::solveCurrentStep() -the ConvergenceTest object failed in test()
StaticAnalysis::analyze() - the Algorithm failed at iteration: 0 with domain at load factor -491.774
OpenSees > analyze failed, returned: -3 error flag
Trying Newton with Initial Tangent ..
DONE Cyclic analysis: CtrlNode 003, dof 2, Disp=1.9602 inch
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End of script <D:\Research\OpenSees\Phuong> reached, Press any key to continue

[kovacsma]

Aahashib, as per your code:
# create load pattern for lateral pushover load
set Hload [expr $Beamweight/20.]; # define the lateral load as a proportion of the weight so that the pseudo time equals the lateral-load coefficient when using linear load pattern
set iPushNode 2; # define nodes where lateral load is applied in static lateral analysis

I think these lines of your code answer your first question.

Regarding the second question:
I think you need to step back and look at the fundamentals of the situation: 2 rollers for a simply supported structure would not be sufficiently constrained to do an analysis. I think this should answer your second question.

Regarding the third question: I will let a more experienced user respond, but in a brief look at the code, I see that the end of the "if convergence failure" code is reached, in your outputs... It seems to have gone all the way to:
if {$ok != 0} {
set putout [format $fmt1 "PROBLEM" $IDctrlNode $IDctrlDOF [nodeDisp $IDctrlNode $IDctrlDOF] $LunitTXT]
puts $putout

I hope this helps.

[aahashib]

It would be a great help if you would kindly write me those extra commands or the modification I need to do to apply loads in two nodes.

Thank you so much for your cooperation.