# Scalar Material Damage

Scalar damage model for which the damage is prescribed by another material

## Description

ScalarMaterialDamage is a model to define the effect of damage on the stress and stiffness in a continuum damage mechanics setting. It does not directly compute the stress, but must be used in conjunction with ComputeDamageStress.

This model is a scalar damage model that does not compute the evolution of damage by itself, but relies on another material model to supply a scalar damage index, which can vary between 0 (undamaged) and 1 (fully damaged). This model is mostly intended for use in testing the continuum damage mecahnics system, but could be used for modeling physical behavior if that were included in the model supplying the damage index.

## Input Parameters

• damage_indexName of the material property containing the damage index, which goes from 0 (undamaged) to 1 (fully damaged)

C++ Type:MaterialPropertyName

Options:

Description:Name of the material property containing the damage index, which goes from 0 (undamaged) to 1 (fully damaged)

### Required Parameters

• base_nameOptional parameter that allows the user to define multiple mechanics material systems on the same block, i.e. for multiple phases

C++ Type:std::string

Options:

Description:Optional parameter that allows the user to define multiple mechanics material systems on the same block, i.e. for multiple phases

• damage_index_namedamage_indexname of the material property where the damage index is stored

Default:damage_index

C++ Type:std::string

Options:

Description:name of the material property where the damage index is stored

• use_old_damageFalseWhether to use the damage index from the previous step in the stress computation

Default:False

C++ Type:bool

Options:

Description:Whether to use the damage index from the previous step in the stress computation

• maximum_damage_increment0.1maximum damage increment allowed for simulations with adaptative time step

Default:0.1

C++ Type:double

Options:

Description:maximum damage increment allowed for simulations with adaptative time step

• boundaryThe list of boundary IDs from the mesh where this boundary condition applies

C++ Type:std::vector

Options:

Description:The list of boundary IDs from the mesh where this boundary condition applies

• blockThe list of block ids (SubdomainID) that this object will be applied

C++ Type:std::vector

Options:

Description:The list of block ids (SubdomainID) that this object will be applied

• residual_stiffness_fraction1e-08Minimum fraction of original material stiffness retained for fully damaged material (when damage_index=1)

Default:1e-08

C++ Type:double

Options:

Description:Minimum fraction of original material stiffness retained for fully damaged material (when damage_index=1)

### Optional Parameters

• enableTrueSet the enabled status of the MooseObject.

Default:True

C++ Type:bool

Options:

Description:Set the enabled status of the MooseObject.

• use_displaced_meshFalseWhether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.

Default:False

C++ Type:bool

Options:

Description:Whether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.

• control_tagsAdds user-defined labels for accessing object parameters via control logic.

C++ Type:std::vector

Options:

Description:Adds user-defined labels for accessing object parameters via control logic.

• seed0The seed for the master random number generator

Default:0

C++ Type:unsigned int

Options:

Description:The seed for the master random number generator

• implicitTrueDetermines whether this object is calculated using an implicit or explicit form

Default:True

C++ Type:bool

Options:

Description:Determines whether this object is calculated using an implicit or explicit form

• constant_onNONEWhen ELEMENT, MOOSE will only call computeQpProperties() for the 0th quadrature point, and then copy that value to the other qps.When SUBDOMAIN, MOOSE will only call computeSubdomainProperties() for the 0th quadrature point, and then copy that value to the other qps. Evaluations on element qps will be skipped

Default:NONE

C++ Type:MooseEnum

Options:NONE ELEMENT SUBDOMAIN

Description:When ELEMENT, MOOSE will only call computeQpProperties() for the 0th quadrature point, and then copy that value to the other qps.When SUBDOMAIN, MOOSE will only call computeSubdomainProperties() for the 0th quadrature point, and then copy that value to the other qps. Evaluations on element qps will be skipped

• output_propertiesList of material properties, from this material, to output (outputs must also be defined to an output type)

C++ Type:std::vector

Options:

Description:List of material properties, from this material, to output (outputs must also be defined to an output type)

• outputsnone Vector of output names were you would like to restrict the output of variables(s) associated with this object

Default:none

C++ Type:std::vector

Options:

Description:Vector of output names were you would like to restrict the output of variables(s) associated with this object