Isotropic Plastic Softening Material - Revision history

Nairnj: /* Examples */

2026-03-29T17:36:58Z

Examples

← Older revision		Revision as of 17:36, 29 March 2026
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	Ep 200		Ep 200
	Done		Done

			== References ==

			<references>

			<ref name="dmGen">J. A. Nairn, "Generalization of Anisotropic Damage Mechanics Modeling in the Material Point Method," ''Int. J. for Numerical Methods in Engineering'', '''123''', 5072-5097 (2022). ([https://www.cof.orst.edu/cof/wse/faculty/Nairn/papers/GenDamage.pdf See PDF])</ref>

			</references>

Nairnj: /* Constitutive Law */

2026-03-29T17:36:37Z

Constitutive Law

← Older revision		Revision as of 17:36, 29 March 2026
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	== Constitutive Law ==		== Constitutive Law ==

	This [[Material Models#Softening Materials\|MPM softening material]] is an isotropic, elastic-plastic material that can also develop anisotropic damage.		This [[Material Models#Softening Materials\|MPM softening material]] is an isotropic, elastic-plastic material that can also develop anisotropic damage.<ref name="dmGen"/>

	In the absence of damage, this material is identical to an [[Isotropic, Elastic-Plastic Material]]. In the absence of plasticity, this material is identical to an [[Isotropic 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.		In the absence of damage, this material is identical to an [[Isotropic, Elastic-Plastic Material]]. In the absence of plasticity, this material is identical to an [[Isotropic 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.

Nairnj: /* Constitutive Law */

2023-11-18T17:48:31Z

Constitutive Law

← Older revision		Revision as of 17:48, 18 November 2023
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	== Constitutive Law ==		== Constitutive Law ==

	This [[Material Models\|MPM ~~Material~~]] is an isotropic, elastic-plastic material that can also develop anisotropic damage.		This [[Material Models#Softening Materials\|MPM softening material]] is an isotropic, elastic-plastic material that can also develop anisotropic damage.

	In the absence of damage, this material is identical to an [[Isotropic, Elastic-Plastic Material]]. In the absence of plasticity, this material is identical to an [[Isotropic 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.		In the absence of damage, this material is identical to an [[Isotropic, Elastic-Plastic Material]]. In the absence of plasticity, this material is identical to an [[Isotropic 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.

Nairnj: /* History Variables */

2023-09-21T21:19:46Z

History Variables

← Older revision		Revision as of 21:19, 21 September 2023
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	* 1 to P: Plastic law history variables		* 1 to P: Plastic law history variables
	* P+1 to P+S: [[Isotropic Softening Material]] history ~~variables~~		* P+1 to P+S: [[Isotropic 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		* P+S+1: 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		* P+S+2: γ<sub>c,xy</sub> or x-y direction shear cracking strain in the crack axis system

Nairnj: /* History Variables */

2023-09-21T21:16:21Z

History Variables

← Older revision		Revision as of 21:16, 21 September 2023
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	* 1 to P: Plastic law history variables		* 1 to P: Plastic law history variables
	* P+1 to P+S: [[Isotropic Softening Material]] history variables		* P+1 to P+S: [[Isotropic Softening Material]] history variables
	** P+10: In 2D has total dissipated energy by damage mechanics (in [[ConsistentUnits Command#Legacy and Consistent Units\|energy units]])
	* P+S+1: ε<sub>c,xx</sub> or x direction cracking strain normal to crack in the crack axis system		* P+S+1: 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		* P+S+2: γ<sub>c,xy</sub> or x-y direction shear cracking strain in the crack axis system

Nairnj: /* History Variables */

2023-09-15T06:57:06Z

History Variables

← Older revision		Revision as of 06:57, 15 September 2023
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	* 1 to P: Plastic law history variables		* 1 to P: Plastic law history variables
	* P+1 to P+S: [[Isotropic Softening Material]] history variables		* P+1 to P+S: [[Isotropic Softening Material]] history variables
	** P+10: In 2D has total dissipated energy by damage mechanics (in [[ConsistentUnits Command#Legacy and Consistent Units\|~~Energy~~ units]])		** P+10: In 2D has total dissipated energy by damage mechanics (in [[ConsistentUnits Command#Legacy and Consistent Units\|energy units]])
	* P+S+1: ε<sub>c,xx</sub> or x direction cracking strain normal to crack in the crack axis system		* P+S+1: 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		* P+S+2: γ<sub>c,xy</sub> or x-y direction shear cracking strain in the crack axis system

Nairnj: /* History Variables */

2023-09-15T06:53:30Z

History Variables

← Older revision		Revision as of 06:53, 15 September 2023
Line 30:		Line 30:
	* 1 to P: Plastic law history variables		* 1 to P: Plastic law history variables
	* P+1 to P+S: [[Isotropic Softening Material]] history variables		* P+1 to P+S: [[Isotropic Softening Material]] history variables
	** P+10: In 2D has total dissipated energy by damage mechanics (in [[ConsistentUnits Command#Legacy and Consistent Units\|Energy units]]))		** P+10: In 2D has total dissipated energy by damage mechanics (in [[ConsistentUnits Command#Legacy and Consistent Units\|Energy units]])
	* P+S+1: ε<sub>c,xx</sub> or x direction cracking strain normal to crack in the crack axis system		* P+S+1: 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		* P+S+2: γ<sub>c,xy</sub> or x-y direction shear cracking strain in the crack axis system

Nairnj: /* History Variables */

2023-09-15T06:53:15Z

History Variables

← Older revision		Revision as of 06:53, 15 September 2023
Line 30:		Line 30:
	* 1 to P: Plastic law history variables		* 1 to P: Plastic law history variables
	* P+1 to P+S: [[Isotropic Softening Material]] history variables		* P+1 to P+S: [[Isotropic Softening Material]] history variables
	** P+10: In 2D has total dissipated energy by damage mechanics (in )		** P+10: In 2D has total dissipated energy by damage mechanics (in [[ConsistentUnits Command#Legacy and Consistent Units\|Energy units]]))
	* P+S+1: ε<sub>c,xx</sub> or x direction cracking strain normal to crack in the crack axis system		* P+S+1: 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		* P+S+2: γ<sub>c,xy</sub> or x-y direction shear cracking strain in the crack axis system

Nairnj: /* History Variables */

2023-09-15T06:51:48Z

History Variables

← Older revision		Revision as of 06:51, 15 September 2023
Line 30:		Line 30:
	* 1 to P: Plastic law history variables		* 1 to P: Plastic law history variables
	* P+1 to P+S: [[Isotropic Softening Material]] history variables		* P+1 to P+S: [[Isotropic Softening Material]] history variables
			** P+10: In 2D has total dissipated energy by damage mechanics (in )
	* P+S+1: ε<sub>c,xx</sub> or x direction cracking strain normal to crack in the crack axis system		* P+S+1: 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		* P+S+2: γ<sub>c,xy</sub> or x-y direction shear cracking strain in the crack axis system

Nairnj: /* History Variables */

2022-02-02T22:24:20Z

History Variables

← Older revision		Revision as of 22:24, 2 February 2022
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	* P+S+3: γ<sub>c,xz</sub> or x-z 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

	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.		For example when P=1 and S=13, this material defines 17 history variables.
			This material also tracks plastic strain, which can be saved by using the [[MPM Archiving Options\|<tt>plasticstrain</tt> archiving option]]. The total plastic strain 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.