Problem in Rotational Hinge

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Prafullamalla
Posts: 160
Joined: Mon Feb 02, 2015 6:32 pm

Problem in Rotational Hinge

Post by Prafullamalla » Thu Oct 25, 2018 8:01 pm

I tried to modal considering the rotational Hinge but changing the parameter of rotational hinge, Fy and Es doesn't change. Is it due to 2 DOF, that I cant apply rotational hinge in quad element?I could not find the reason for it. Here, is the code.

# ################################
# create the modelbuilder
# #################################
wipe
model BasicBuilder -ndm 2 -ndf 2
# ################################
# build the model
# #################################
# y
# |
# 8-------7
# | slave |
# 5-------6
# 4-------3
# | master|
# 1-------2---->x
#
set L 1;
set H 0.5;
set Tol 0;
node 1 0 0
node 2 $L 0
node 3 $L [expr $H+$Tol]
node 4 0 [expr $H+$Tol]
node 5 0 [expr $H-$Tol]
node 6 $L [expr $H-$Tol]
node 7 $L [expr 2*$H]
node 8 0 [expr 2*$H]

fix 1 1 1
fix 2 1 1

#nDMaterial ElasticIsotropic 1 1e16 0.3 ### no mass density, dont use it
##nDMaterial J2Plasticity tag? rho? K? G? sig0? sigInf? delta? H? <eta?>
nDMaterial J2Plasticity 1 200 1e10 1e10 1e16 1e20 0 0

#element bbarQuad 1 1 2 4 3 PlaneStrain 1
element quad 1 1 2 3 4 1 PlaneStrain 1
element quad 2 5 6 7 8 1 PlaneStrain 1

# Create Rotational Hinge at4/5 and 3/6
# define material for Rotational Hinge
set matID_RH 44
set Fy 50.0
set Es 20000.0
set b 0.003; # strain hardening ratio
uniaxialMaterial Steel02 $matID_RH $Fy $Es $b 20 0.925 0.15 0.0005 0.01 0.0005 0.01
# command arguemnts: $eleTag $iNode $jNode -mat $matTag1 $matTag2 ... -dir $dir1 $dir2
element zeroLength 11 5 4 -mat $matID_RH -dir 6
element zeroLength 12 6 3 -mat $matID_RH -dir 6
# element zeroLengthContact2D $eleTag $sNode $mNode $Kn $Kt $mu -normal $Nx $Ny
#element zeroLengthContact2D 13 5 4 1.0e+5 0.5e+5 0.8 -normal 0 1;
#element zeroLengthContact2D 14 6 3 1.0e+5 0.5e+5 0.8 -normal 0 1;

set Vload -1000
set Hload 10000
#set Hload 0
# Constant point load
pattern Plain 1 Constant {
load 7 0.0 [expr $Vload/2]
load 8 0.0 [expr $Vload/2]
load 5 [expr $Hload/2] 0.0
load 6 [expr $Hload/2] 0.0
}
# recorde disp at node 3 and reactions at the bottom nodels
recorder Node -file "nodedisp.out" -time -node 7 -dof 1 disp
# ################################
# create the analysis
# displacement parameters
set IDctrlNode 7; # node where disp is read for disp control
set IDctrlDOF 1; # degree of freedom read for disp control (1 = x displacement)
set Dmax 5; # maximum displacement of pushover
set Dincr [expr $Dmax/1000.]; # displacement increment

# pushover analysis commands
constraints Plain;
numberer RCM;
system BandGeneral;
test NormUnbalance 1.0e-6 10;
algorithm Newton;
integrator DisplacementControl $IDctrlNode $IDctrlDOF $Dincr;
analysis Static;
set ok 0
set currentDisp 0.0
while {$ok == 0 && $currentDisp < $Dmax} {
set ok [analyze 1]
if {$ok != 0} {
test NormDispIncr 1.0e-6 1000 1
algorithm Newton –initial
set ok [analyze 1]
test NormDispIncr 1.0e-6 10
algorithm Newton
}
set currentDisp [nodeDisp $IDctrlNode 1]
}
puts "node7disp: [nodeDisp 7 1]"
wipe all;
Prafulla Malla, Nepal
Praf_malla@hotmail.com

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