Hysteresis Material

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soorour
Posts: 1
Joined: Sat Nov 11, 2017 8:51 am

Hysteresis Material

Post by soorour » Sat Nov 11, 2017 10:52 am

Hi everyone
I have used a truss element assigned with “pinched hysteresis” material which can only resist “tension” but its cyclic behavior is kind of weird because during unloading process, the element does not completely go back to zero load. Would you please tell me how I can fix this problem?

wipe
model basic -ndm 2 -ndf 3

node 1 0. 0.
node 2 2.296 0.

fix 1 1 1 1
fix 2 0 1 1

uniaxialMaterial Hysteretic 8 202.e6 0.001 270.e6 0.068 285.e6 0.15 -1. -0.001 -2. -0.068 -3. -0.15 0.00001 1.0 0.0 0.0
element truss 41 1 2 1.8e-4 8

recorder Node -file node2disp.out -time -node 2 -dof 1 2 3 disp
recorder plot node2disp.out Displacement 800 100 500 500 -columns 2 1

recorder display Frame 100 100 500 500 -wipe
vup 0 1 0
vpn 0 0 1
prp 1 1 1
viewWindow -3 3 -3 3
display 1 5 1
pattern Plain 1 Linear {
load 2 1000. 0. 0.
}
constraints Plain
numberer Plain
system BandGeneral
test NormDispIncr 1.e-6 25
algorithm KrylovNewton

set disloop [list 0.4 0.4 -0.4 -0.4]
for {set i 1} {$i<= [llength $disloop]} {incr i 1} {
set dispincr [expr 1.0*pow((-1), [expr $i-1])*[lindex $disloop [expr $i-1]]/300]
integrator DisplacementControl 2 1 $dispincr
analysis Static
analyze 300
}

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