Hysteretic Material
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Hysteretic Material
When using the Hysteretic Material, do the assigned values of the diagram correspond to normalised (to the yielding point) stresses and/or strains?
Re: Hysteretic Material
You assign the stress and strain (or force and deformation) directly for the hysteretic material. You could set up your code to assign the direct values based off of a normalization, if you desire to.
This is an example of how to define a hysteretic material based off of the yield moment and rotation of a concrete section.
Example:
set hystereticMatTag 1; # Material tag
set rotMy 2.e-4 ; # Yield rotation radians
set rotMu [expr 12.*$rotMy] ; # Ultimate rotation
set rotMcr [expr $rotMy/10.]; # Cracking Rotation
set My 4300. ; # Yield moment kip-inch
set Mu [expr 1.2*$My] ; # Ultimate moment
set Mcr [expr 0.2*$My] ; # Cracking moment
# Hysteresis Parameters
set pinchX 0.5
set pinchY 0.4
set damage1 0.
set damage2 0.
set beta 0.4
# Material Definition
uniaxialMaterial Hysteretic $hystereticMatTag $Mcr $rotMcr $My $rotMy $Mu $rotMu [expr -$Mcr] [expr -$rotMcr] [expr -$My] [expr -$rotMy] [expr -$Mu] [expr -$rotMu] $pinchX $pinchY $damage1 $damage2 $beta
This is an example of how to define a hysteretic material based off of the yield moment and rotation of a concrete section.
Example:
set hystereticMatTag 1; # Material tag
set rotMy 2.e-4 ; # Yield rotation radians
set rotMu [expr 12.*$rotMy] ; # Ultimate rotation
set rotMcr [expr $rotMy/10.]; # Cracking Rotation
set My 4300. ; # Yield moment kip-inch
set Mu [expr 1.2*$My] ; # Ultimate moment
set Mcr [expr 0.2*$My] ; # Cracking moment
# Hysteresis Parameters
set pinchX 0.5
set pinchY 0.4
set damage1 0.
set damage2 0.
set beta 0.4
# Material Definition
uniaxialMaterial Hysteretic $hystereticMatTag $Mcr $rotMcr $My $rotMy $Mu $rotMu [expr -$Mcr] [expr -$rotMcr] [expr -$My] [expr -$rotMy] [expr -$Mu] [expr -$rotMu] $pinchX $pinchY $damage1 $damage2 $beta
Re: Hysteretic Material
Thank you nskok...
So did i understand well that normaly i give direct values of rotations (rads) and moments (kNm) without making any kind of set up in the code?
(Actually, i didn't understand when you said "..based off of the yield moment and rotation..", i mean i didn't caught the phrase: "based off")
So did i understand well that normaly i give direct values of rotations (rads) and moments (kNm) without making any kind of set up in the code?
(Actually, i didn't understand when you said "..based off of the yield moment and rotation..", i mean i didn't caught the phrase: "based off")
Re: Hysteretic Material
Correct, the hysteretic material requires the direct values of stress and strain (or force and deformation).
Sorry for the confusion. In the example, I was demonstrating how to use the second point of the envelope to define the first and third points. In this case, I used the yield moment (point 2) to define the cracking moment (point 1) and the ultimate moment (point 3). If you want to generate the direct values from a normalization, this is a way it can be done.
Sorry for the confusion. In the example, I was demonstrating how to use the second point of the envelope to define the first and third points. In this case, I used the yield moment (point 2) to define the cracking moment (point 1) and the ultimate moment (point 3). If you want to generate the direct values from a normalization, this is a way it can be done.
Re: Hysteretic Material
O.k thanks a lot.
Re: Hysteretic Material
A question related to this: Is the hysteretic material more properly used with both positive and negative values instead of only positive? I ask this because i have seen that many users had some "complaints" when they used it like that.. Any experience on that?