CappedDruckerPragerStressUpdate

buildconstruction:Undocumented Class

The CappedDruckerPragerStressUpdate has not been documented. The content listed below should be used as a starting point for documenting the class, which includes the typical automatic documentation associated with a MooseObject; however, what is contained is ultimately determined by what is necessary to make the documentation clear for users.

Capped Drucker-Prager plasticity stress calculator

Overview

Example Input File Syntax

Input Parameters

  • DP_modelA SolidMechanicsPlasticDruckerPrager UserObject that defines the Drucker-Prager parameters (cohesion, friction angle and dilation angle)

    C++ Type:UserObjectName

    Controllable:No

    Description:A SolidMechanicsPlasticDruckerPrager UserObject that defines the Drucker-Prager parameters (cohesion, friction angle and dilation angle)

  • compressive_strengthA SolidMechanicsHardening UserObject that defines hardening of the compressive strength. In physical situations this is positive.

    C++ Type:UserObjectName

    Controllable:No

    Description:A SolidMechanicsHardening UserObject that defines hardening of the compressive strength. In physical situations this is positive.

  • smoothing_tolIntersections of the yield surfaces will be smoothed by this amount (this is measured in units of stress). Often this is related to other physical parameters (eg, 0.1*cohesion) but it is important to set this small enough so that the individual yield surfaces do not mix together in the smoothing process to produce a result where no stress is admissible (for example, mixing together tensile and compressive failure envelopes).

    C++ Type:double

    Controllable:No

    Description:Intersections of the yield surfaces will be smoothed by this amount (this is measured in units of stress). Often this is related to other physical parameters (eg, 0.1*cohesion) but it is important to set this small enough so that the individual yield surfaces do not mix together in the smoothing process to produce a result where no stress is admissible (for example, mixing together tensile and compressive failure envelopes).

  • tensile_strengthA SolidMechanicsHardening UserObject that defines hardening of the tensile strength. In physical situations this is positive (and always must be greater than negative compressive-strength.

    C++ Type:UserObjectName

    Controllable:No

    Description:A SolidMechanicsHardening UserObject that defines hardening of the tensile strength. In physical situations this is positive (and always must be greater than negative compressive-strength.

  • tip_smootherThe cone vertex at J2 = 0 will be smoothed by the given amount. Typical value is 0.1*cohesion

    C++ Type:double

    Controllable:No

    Description:The cone vertex at J2 = 0 will be smoothed by the given amount. Typical value is 0.1*cohesion

  • yield_function_tolThe return-map process will be deemed to have converged if all yield functions are within yield_function_tol of zero. If this is set very low then precision-loss might be encountered: if the code detects precision loss then it also deems the return-map process has converged.

    C++ Type:double

    Controllable:No

    Description:The return-map process will be deemed to have converged if all yield functions are within yield_function_tol of zero. If this is set very low then precision-loss might be encountered: if the code detects precision loss then it also deems the return-map process has converged.

Required Parameters

  • admissible_stressA single admissible value of the value of the stress parameters for internal parameters = 0. This is used to initialize the return-mapping algorithm during the first nonlinear iteration. If not given then it is assumed that stress parameters = 0 is admissible.

    C++ Type:std::vector<double>

    Controllable:No

    Description:A single admissible value of the value of the stress parameters for internal parameters = 0. This is used to initialize the return-mapping algorithm during the first nonlinear iteration. If not given then it is assumed that stress parameters = 0 is admissible.

  • base_nameOptional parameter that defines a prefix for all material properties related to this stress update model. This allows for multiple models of the same type to be used without naming conflicts.

    C++ Type:std::string

    Controllable:No

    Description:Optional parameter that defines a prefix for all material properties related to this stress update model. This allows for multiple models of the same type to be used without naming conflicts.

  • blockThe list of blocks (ids or names) that this object will be applied

    C++ Type:std::vector<SubdomainName>

    Controllable:No

    Description:The list of blocks (ids or names) that this object will be applied

  • boundaryThe list of boundaries (ids or names) from the mesh where this object applies

    C++ Type:std::vector<BoundaryName>

    Controllable:No

    Description:The list of boundaries (ids or names) from the mesh where this object applies

  • 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 computeQpProperties() 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

    Controllable:No

    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 computeQpProperties() for the 0th quadrature point, and then copy that value to the other qps. Evaluations on element qps will be skipped

  • declare_suffixAn optional suffix parameter that can be appended to any declared properties. The suffix will be prepended with a '_' character.

    C++ Type:MaterialPropertyName

    Controllable:No

    Description:An optional suffix parameter that can be appended to any declared properties. The suffix will be prepended with a '_' character.

  • max_NR_iterations20Maximum number of Newton-Raphson iterations allowed during the return-map algorithm

    Default:20

    C++ Type:unsigned int

    Controllable:No

    Description:Maximum number of Newton-Raphson iterations allowed during the return-map algorithm

  • min_step_size1In order to help the Newton-Raphson procedure, the applied strain increment may be applied in sub-increments of size greater than this value. Usually it is better for Moose's nonlinear convergence to increase max_NR_iterations rather than decrease this parameter.

    Default:1

    C++ Type:double

    Controllable:No

    Description:In order to help the Newton-Raphson procedure, the applied strain increment may be applied in sub-increments of size greater than this value. Usually it is better for Moose's nonlinear convergence to increase max_NR_iterations rather than decrease this parameter.

  • perfect_guessTrueProvide a guess to the Newton-Raphson procedure that is the result from perfect plasticity. With severe hardening/softening this may be suboptimal.

    Default:True

    C++ Type:bool

    Controllable:No

    Description:Provide a guess to the Newton-Raphson procedure that is the result from perfect plasticity. With severe hardening/softening this may be suboptimal.

  • perform_finite_strain_rotationsFalseTensors are correctly rotated in finite-strain simulations. For optimal performance you can set this to 'false' if you are only ever using small strains

    Default:False

    C++ Type:bool

    Controllable:No

    Description:Tensors are correctly rotated in finite-strain simulations. For optimal performance you can set this to 'false' if you are only ever using small strains

  • prop_getter_suffixAn optional suffix parameter that can be appended to any attempt to retrieve/get material properties. The suffix will be prepended with a '_' character.

    C++ Type:MaterialPropertyName

    Controllable:No

    Description:An optional suffix parameter that can be appended to any attempt to retrieve/get material properties. The suffix will be prepended with a '_' character.

  • small_dilationTrueIf true, and if the trial stress exceeds the tensile strength, then the user guarantees that the returned stress will be independent of the compressive strength.

    Default:True

    C++ Type:bool

    Controllable:No

    Description:If true, and if the trial stress exceeds the tensile strength, then the user guarantees that the returned stress will be independent of the compressive strength.

  • use_interpolated_stateFalseFor the old and older state use projected material properties interpolated at the quadrature points. To set up projection use the ProjectedStatefulMaterialStorageAction.

    Default:False

    C++ Type:bool

    Controllable:No

    Description:For the old and older state use projected material properties interpolated at the quadrature points. To set up projection use the ProjectedStatefulMaterialStorageAction.

  • warn_about_precision_lossFalseOutput a message to the console every time precision-loss is encountered during the Newton-Raphson process

    Default:False

    C++ Type:bool

    Controllable:No

    Description:Output a message to the console every time precision-loss is encountered during the Newton-Raphson process

Optional Parameters

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

    C++ Type:std::vector<std::string>

    Controllable:No

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

  • enableTrueSet the enabled status of the MooseObject.

    Default:True

    C++ Type:bool

    Controllable:Yes

    Description:Set the enabled status of the MooseObject.

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

    Default:True

    C++ Type:bool

    Controllable:No

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

  • seed0The seed for the master random number generator

    Default:0

    C++ Type:unsigned int

    Controllable:No

    Description:The seed for the master random number generator

  • smoother_function_typecosType of smoother function to use. 'cos' means (-a/pi)cos(pi x/2/a), 'polyN' means a polynomial of degree 2N+2

    Default:cos

    C++ Type:MooseEnum

    Options:cos, poly1, poly2, poly3

    Controllable:No

    Description:Type of smoother function to use. 'cos' means (-a/pi)cos(pi x/2/a), 'polyN' means a polynomial of degree 2N+2

  • 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

    Controllable:No

    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.

Advanced Parameters

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

    C++ Type:std::vector<std::string>

    Controllable:No

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

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

    Default:none

    C++ Type:std::vector<OutputName>

    Controllable:No

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

Outputs Parameters

Input Files

Child Objects