Detailed Description

This class defines a linear saturation rate dependent swelling stress model for the materials that swell strongly when water content increases.

Clay materials like bentonite have a high swelling capacity in dry state, and their swelling property can be described by this model.

The original model was proposed in [34] (equations (39) and (40) on pages 758–759). With a simplification of the parameters of the original formula and introducing a constraint to avoid shrinkage stress when saturation is below the initial saturation, the model takes the form

\[ {\mathbf{\sigma}}^{\text{sw}} = {\alpha}_{\text{sw}} (S-S_0) \mathbf{I}, \, \forall S \in [S_0, S_\text{max}] \]

where \({\alpha}_{\text{sw}}\) is a coefficient, and \(S_0\) is the initial saturation, and \(S_{\text{max}}\) is the maximum saturation. The coefficient gives the swelling stress at full saturation, which can be computed as

\[ {\alpha}_{\text{sw}} = \frac{{{\sigma}}^{\text{sw}}_{\text{max}}}{(S_{\text{max}}-S_0)} \]

where \({{\sigma}}^{\text{sw}}_{\text{max}}\) represents the swelling stress at full saturation.

In the numerical analysis, the stress always takes the incremental form. Therefore the model becomes as

\[\Delta {\mathbf{\sigma}}^{\text{sw}} = {\alpha}_{\text{sw}} \Delta S \mathbf{I}, \, \forall S \in [S_0, S_\text{max}] \]

Note:

In the property, saturation means water saturation.
The upper limit of saturation is not guaranteed, but it is required to be less or equal to \(S_\text{max}\) when calling this property. Therefore it is not checked again in this class.Thus, this model only needs two input parameters: \({\alpha}_{\text{sw}}\) and \(S_0\).

Definition at line 63 of file LinearSaturationSwellingStress.h.

#include <LinearSaturationSwellingStress.h>

Inheritance diagram for MaterialPropertyLib::LinearSaturationSwellingStress:

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Collaboration diagram for MaterialPropertyLib::LinearSaturationSwellingStress:

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Public Member Functions
	LinearSaturationSwellingStress (std::string name, double const coefficient, double const reference_saturation)

void	checkScale () const override

PropertyDataType	value (VariableArray const &variable_array, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const override

PropertyDataType	value (VariableArray const &variable_array, VariableArray const &variable_array_prev, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const override

PropertyDataType	dValue (VariableArray const &variable_array, Variable const variable, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const override

Public Member Functions inherited from MaterialPropertyLib::Property
virtual	~Property ()

virtual PropertyDataType	initialValue (ParameterLib::SpatialPosition const &pos, double const t) const

virtual PropertyDataType	value () const

virtual PropertyDataType	dValue (VariableArray const &variable_array, VariableArray const &variable_array_prev, Variable const variable, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const

virtual PropertyDataType	d2Value (VariableArray const &variable_array, Variable const variable1, Variable const variable2, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const
	Default implementation: 2nd derivative of any constant property is zero.

virtual void	setProperties (std::vector< std::unique_ptr< Phase > > const &phases)
	Default implementation:

void	setScale (std::variant< Medium , Phase , Component * > scale)

template<typename T >
T	initialValue (ParameterLib::SpatialPosition const &pos, double const t) const

template<typename T >
T	value () const

template<typename T >
T	value (VariableArray const &variable_array, VariableArray const &variable_array_prev, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const

template<typename T >
T	value (VariableArray const &variable_array, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const

template<typename T >
T	dValue (VariableArray const &variable_array, VariableArray const &variable_array_prev, Variable const variable, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const

template<typename T >
T	dValue (VariableArray const &variable_array, Variable const variable, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const

template<typename T >
T	d2Value (VariableArray const &variable_array, Variable const &variable1, Variable const &variable2, ParameterLib::SpatialPosition const &pos, double const t, double const dt) const

Private Attributes
double const	coefficient_

double const	reference_saturation_

Additional Inherited Members
Protected Attributes inherited from MaterialPropertyLib::Property
std::string	name_

PropertyDataType	value_
	The single value of a property.

PropertyDataType	dvalue_

std::variant< Medium , Phase , Component * >	scale_

Constructor & Destructor Documentation

◆ LinearSaturationSwellingStress()

MaterialPropertyLib::LinearSaturationSwellingStress::LinearSaturationSwellingStress	(	std::string	name,
		double const	coefficient,
		double const	reference_saturation )

Definition at line 19 of file LinearSaturationSwellingStress.cpp.

    : coefficient_(coefficient), reference_saturation_(reference_saturation)
{
    name_ = std::move(name);
}

References MaterialPropertyLib::name, and MaterialPropertyLib::Property::name_.

Member Function Documentation

◆ checkScale()

void MaterialPropertyLib::LinearSaturationSwellingStress::checkScale ( ) const

inlineoverridevirtual

Reimplemented from MaterialPropertyLib::Property.

Definition at line 70 of file LinearSaturationSwellingStress.h.

    {
        if (!std::holds_alternative<Phase*>(scale_))
        {
            OGS_FATAL(
                "The property 'LinearSaturationSwellingStress' is "
                "implemented on the 'phase' scale only.");
        }
    }

References OGS_FATAL, and MaterialPropertyLib::Property::scale_.

◆ dValue()

PropertyDataType MaterialPropertyLib::LinearSaturationSwellingStress::dValue	(	VariableArray const &	variable_array,
		Variable const	variable,
		ParameterLib::SpatialPosition const &	pos,
		double const	t,
		double const	dt ) const

overridevirtual

Returns: \( \frac{ \partial \Delta {{\sigma}}^{\text{sw}}}{\partial S}\).

Reimplemented from MaterialPropertyLib::Property.

Definition at line 57 of file LinearSaturationSwellingStress.cpp.

{
    if (variable != Variable::liquid_saturation)
    {
        OGS_FATAL(
            "LinearSaturationSwellingStress::dValue is implemented for "
            "derivatives with respect to liquid saturation only.");
    }
 
    // Sl <= S_max is guaranteed by the saturation property or
    // the saturation calculation.
    const double Sl = variable_array.liquid_saturation;
 
    return Sl < reference_saturation_ ? 0.0 : coefficient_;
}

References coefficient_, MaterialPropertyLib::liquid_saturation, MaterialPropertyLib::VariableArray::liquid_saturation, OGS_FATAL, and reference_saturation_.

◆ value() [1/2]

PropertyDataType MaterialPropertyLib::LinearSaturationSwellingStress::value	(	VariableArray const &	variable_array,
		ParameterLib::SpatialPosition const &	pos,
		double const	t,
		double const	dt ) const

overridevirtual

This virtual method will compute the property value based on the variables that are passed as arguments with the default implementation using empty variables array for the previous time step.

Reimplemented from MaterialPropertyLib::Property.

Definition at line 27 of file LinearSaturationSwellingStress.cpp.

{
    OGS_FATAL(
        "LinearSaturationSwellingStress value call requires previous time step "
        "values.");
}

References OGS_FATAL.

◆ value() [2/2]

PropertyDataType MaterialPropertyLib::LinearSaturationSwellingStress::value	(	VariableArray const &	variable_array,
		VariableArray const &	variable_array_prev,
		ParameterLib::SpatialPosition const &	pos,
		double const	t,
		double const	dt ) const

overridevirtual

Returns: \(\Delta {{\sigma}}^{\text{sw}} \).

Reimplemented from MaterialPropertyLib::Property.

Definition at line 37 of file LinearSaturationSwellingStress.cpp.

{
    // Sl <= S_max is guaranteed by the saturation property or
    // the saturation calculation.
    const double Sl = variable_array.liquid_saturation;
 
    if (Sl < reference_saturation_)
    {
        return 0.0;
    }
 
    const double Sl_prev = variable_array_prev.liquid_saturation;
 
    return coefficient_ * (Sl - Sl_prev);
}

References coefficient_, MaterialPropertyLib::VariableArray::liquid_saturation, and reference_saturation_.

Member Data Documentation

◆ coefficient_

double const MaterialPropertyLib::LinearSaturationSwellingStress::coefficient_

private

The coefficient of the model, which gives the swelling stress at full saturation. The coefficient can be obtained by

\[ {\alpha}_{\text{sw}} = \frac{{{\sigma}}^{\text{sw}}_{\text{max}}}{(S_{\text{max}}-S_0)} \]

with \({{\sigma}}^{\text{sw}}_{\text{max}}\) the swelling stress at full saturation, and \(S_{\text{max}}\) the maximum saturation.

Definition at line 110 of file LinearSaturationSwellingStress.h.

Referenced by dValue(), and value().

◆ reference_saturation_

double const MaterialPropertyLib::LinearSaturationSwellingStress::reference_saturation_

private

The reference saturation, at which the swelling stress is zero.

Definition at line 114 of file LinearSaturationSwellingStress.h.

Referenced by dValue(), and value().

The documentation for this class was generated from the following files:

MaterialLib/MPL/Properties/SwellingStress/LinearSaturationSwellingStress.h
MaterialLib/MPL/Properties/SwellingStress/LinearSaturationSwellingStress.cpp

Detailed Description

Public Member Functions

Private Attributes

Additional Inherited Members

Constructor & Destructor Documentation

◆ LinearSaturationSwellingStress()

Member Function Documentation

◆ checkScale()

◆ dValue()

◆ value() [1/2]

◆ value() [2/2]

Member Data Documentation

◆ coefficient_

◆ reference_saturation_