Difference between revisions of "Orthotropic Plastic Softening Material"

From OSUPDOCS
Jump to navigation Jump to search
(9 intermediate revisions by the same user not shown)
Line 1: Line 1:
== Constitutive Law ==
== Constitutive Law ==


This [[Material Models|MPM Material]] is an orthotropic, elastic-plastic material that can also develop anisotropic damage. The material is available only in [[OSParticulas]].
(This material is available only in [[OSParticulas]] because it is still in development)


In the absence of damage, this material is identical to a [[Anisotropic, Elastic-Plastic Material]]. In the absence of plasticity, this material is identical to an [[Orthotropic Softening Material]]. If conditions allow, the material can develop both plasticity and damage with softening. Note that if plastic yield properties are below damage initiation stress, the material may never reach stress to cause damage. But, if the plastic properties allow hardening, the material can yield first and then start damage after hardening allowing stresses to reach stress for initiation of damage.
This [[Material Models#Softening Materials|MPM softening material]] is an orthotropic, elastic-plastic material that can also develop anisotropic damage. In the absence of damage, this material is identical to a [[Anisotropic, Elastic-Plastic Material]]. In the absence of plasticity, this material is identical to an [[Orthotropic Softening Material]]. If conditions allow, the material can develop both plasticity and damage with softening. Note that if plastic yield properties are below damage initiation stress, the material may never reach stress to cause damage. But, if the plastic properties allow hardening, the material can yield first and then start damage after hardening allows stresses to reach stress for initiation of damage.


== Material Properties ==
== Material Properties ==
Line 15: Line 15:
| ([[Orthotropic Material#Material Properties|Orthotropic Properties]]) || Enter all properties needed to define the underlying orthotropic material response || varies || varies
| ([[Orthotropic Material#Material Properties|Orthotropic Properties]]) || Enter all properties needed to define the underlying orthotropic material response || varies || varies
|-
|-
| ([[[[Anisotropic, Elastic-Plastic Material]]#Material Properties|Isotropic, Plastic Properties]]) || Enter orthotropic yield properties || varies || varies
| ([[Anisotropic, Elastic-Plastic Material#Material Properties|Orthotropic, Plastic Properties]]) || Enter orthotropic yield properties || varies || varies
|-
|-
| ([[Orthotropic Softening Material#Material Properties|Isotropic Softening Properties]]) || Enter properties for initiation of damage and for two softening laws  || varies || varies
| ([[Orthotropic Softening Material#Material Properties|Orthotropic Softening Properties]]) || Enter properties for initiation of damage and for two softening laws  || varies || varies
|-
|-
| ([[Common Material Properties|other]]) || Properties common to all materials and must use the large rotation option || varies || varies
| ([[Common Material Properties|other]]) || Properties common to all materials and must use the large rotation option || varies || varies
Line 24: Line 24:
== History Variables ==
== History Variables ==


The chosen [[Hardening Laws|hardening law]] will have at least one history variable and will start with history variable number 1. After the  [[Hardening Laws|hardening law]] history variables, the remaining variables will be for the [[Isotropic Softening Material]] material. The softening history variable will be offset by the number of  [[Hardening Laws|hardening law]] history variables. Because plastic strain tracks sum of plastic and cracking strain, three additional history variables (compared to [[Isotropic Softening Material]]) track the three components of cracking strains in the crack axis system corresponding to normal and shear crack opening displacements.
The plasticity modeling for this material uses one history variable and will start with history variable number 1. After that variable, the remaining variables will be for the [[Orthotropic Softening Material]] material. Because plastic strain is used for plasticity, three additional history variables (compared to [[Orthotropic Softening Material]]) track the three components of cracking strains in the crack axis system corresponding to normal and shear crack opening displacements.


Let P and S be number of history variables for the plastic law in use and for damage needed by an [[Isotropic Softening Material]], respectively. The history variables for this material are then:
Let S be number of history variables for damage needed by an [[Orthotropic Softening Material]], respectively. The history variables for this material are then:


* 1 to P: Plastic law history variables
* 1: Plastic law history variable
* P+1 to P+S: [[Isotropic Softening Material]] history variables
* 2 to 1+S: [[Orthotropic Softening Material]] history variable <tt>S</tt>
* P+S+1: ε<sub>c,xx</sub> or x direction cracking strain normal to crack in the crack axis system
* 2+S: ε<sub>c,xx</sub> or x direction cracking strain normal to crack in the crack axis system
* P+S+2: γ<sub>c,xy</sub> or x-y direction shear cracking strain in the crack axis system
* 3+S: γ<sub>c,xy</sub> or x-y direction shear cracking strain in the crack axis system
* P+S+3: γ<sub>c,xz</sub> or x-z direction shear cracking strain in the crack axis system
* 4+S: γ<sub>c,xz</sub> or x-z direction shear cracking strain in the crack axis system


This material also tracks sum of plastic strain and cracking strain which can be saved by using the [[MPM Archiving Options|<tt>plasticstrain</tt> archiving option]]. The total plastic plus cracking strain is archived in the global axis system.
This material also tracks plastic strain which can be saved by using the [[MPM Archiving Options|<tt>plasticstrain</tt> archiving option]]. The total plastic is archived in the global axis system.


If you also [[MPM Archiving Options|archive the <tt>damagenormal</tt>]], you will be able to plot a vector along the crack-opening displacement vector.
If you also [[MPM Archiving Options|archive the <tt>damagenormal</tt>]], you will be able to plot a vector along the crack-opening displacement vector in the crack axis system.

Revision as of 10:49, 18 November 2023

Constitutive Law

(This material is available only in OSParticulas because it is still in development)

This MPM softening material is an orthotropic, elastic-plastic material that can also develop anisotropic damage. In the absence of damage, this material is identical to a Anisotropic, Elastic-Plastic Material. In the absence of plasticity, this material is identical to an Orthotropic Softening Material. If conditions allow, the material can develop both plasticity and damage with softening. Note that if plastic yield properties are below damage initiation stress, the material may never reach stress to cause damage. But, if the plastic properties allow hardening, the material can yield first and then start damage after hardening allows stresses to reach stress for initiation of damage.

Material Properties

For material properties, combine all options available for an Anisotropic, Elastic-Plastic Material and for an Orthotropic Softening Material. This material must, however, use large rotation mode.

Property Description Units Default
(Orthotropic Properties) Enter all properties needed to define the underlying orthotropic material response varies varies
(Orthotropic, Plastic Properties) Enter orthotropic yield properties varies varies
(Orthotropic Softening Properties) Enter properties for initiation of damage and for two softening laws varies varies
(other) Properties common to all materials and must use the large rotation option varies varies

History Variables

The plasticity modeling for this material uses one history variable and will start with history variable number 1. After that variable, the remaining variables will be for the Orthotropic Softening Material material. Because plastic strain is used for plasticity, three additional history variables (compared to Orthotropic Softening Material) track the three components of cracking strains in the crack axis system corresponding to normal and shear crack opening displacements.

Let S be number of history variables for damage needed by an Orthotropic Softening Material, respectively. The history variables for this material are then:

  • 1: Plastic law history variable
  • 2 to 1+S: Orthotropic Softening Material history variable S
  • 2+S: εc,xx or x direction cracking strain normal to crack in the crack axis system
  • 3+S: γc,xy or x-y direction shear cracking strain in the crack axis system
  • 4+S: γc,xz or x-z direction shear cracking strain in the crack axis system

This material also tracks plastic strain which can be saved by using the plasticstrain archiving option. The total plastic is archived in the global axis system.

If you also archive the damagenormal, you will be able to plot a vector along the crack-opening displacement vector in the crack axis system.