## Pinch of hysteresis curve

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### Pinch of hysteresis curve

I'm doing a numerical simulation of a two-story frame under low cyclic loading, but I don't know how to consider the pinch of hysteresis curves? Thanks for your advice.
xiaoyan

Posts: 1
Joined: Sat Jun 23, 2018 3:27 am
Location: ShandongUniversity

### Re: Pinch of hysteresis curve

uniaxialMaterial Hysteretic . you have posted in different group under reliability analysis. So that you might not get response. Post in Opensees.exe user

# reinforcing steel
set Fy [expr 51*\$ksi]; # STEEL yield stress
set Es [expr 30000.*\$ksi]; # modulus of steel
set epsY [expr \$Fy/\$Es]; # steel yield strain
set Fy1 [expr 95.*\$ksi]; # steel stress post-
set epsY1 0.03; # steel strain post-yield
set Fu [expr 95*\$ksi]; # ultimate stress of steel
set epsU 0.08; # ultimate strain of steel
set Bs [expr (\$Fu-\$Fy)/(\$epsU-\$epsY)/\$Es]; # post-yield stiffness ratio of steel
set Bs [expr (\$Fy1-\$Fy)/(\$epsY1-\$epsY)/\$Es]; # post-yield stiffness ratio of steel
set pinchX 1; # pinching parameter for hysteretic model
set pinchY 1; # pinching parameter for hysteretic model
set damage1 0.0; # damage parameter for hysteretic model
set damage2 0.1; # damage parameter for hysteretic model
set betaMUsteel 0.30; # degraded unloading stiffness for hysteretic material based on MU^(-beta)
u
uniaxialMaterial Hysteretic \$IDreinf \$Fy \$epsY \$Fy1 \$epsY1 \$Fu \$epsU -\$Fy -\$epsY -\$Fy1 -\$epsY1 -\$Fu -\$epsU \$pinchX \$pinchY \$damage1 \$damage2 \$betaMUsteel ; # hysteritic reinforcemnet model
Prafullamalla

Posts: 103
Joined: Mon Feb 02, 2015 6:32 pm