diff --git a/ProcessLib/RichardsMechanics/Tests.cmake b/ProcessLib/RichardsMechanics/Tests.cmake
index a3947b88ba673f92c3a5425e623ddbc7d6b2a330..5a9888aba7a862e55f32822281bdd151760faa6b 100644
--- a/ProcessLib/RichardsMechanics/Tests.cmake
+++ b/ProcessLib/RichardsMechanics/Tests.cmake
@@ -182,7 +182,24 @@ AddTest(
GLOB RichardsFlow_2d_richardsflow_pcs_0_ts_*.vtu pressure pressure 5e-11 1e-15
GLOB RichardsFlow_2d_richardsflow_pcs_0_ts_*.vtu saturation saturation 1e-14 1e-15
)
-
+AddTest(
+ NAME RichardsMechanics_deformation_dependent_porosity
+ PATH RichardsMechanics
+ EXECUTABLE ogs
+ EXECUTABLE_ARGS deformation_dependent_porosity.prj
+ WRAPPER time
+ TESTER vtkdiff
+ REQUIREMENTS NOT OGS_USE_MPI
+ DIFF_DATA
+ GLOB deformation_dependent_porosity_pcs_0_ts_*.vtu pressure pressure 5e-11 1e-15
+ GLOB deformation_dependent_porosity_pcs_0_ts_*.vtu saturation saturation 1e-14 0
+ GLOB deformation_dependent_porosity_pcs_0_ts_*.vtu displacement displacement 5e-11 0
+ GLOB deformation_dependent_porosity_pcs_0_ts_*.vtu sigma sigma 1e-14 0
+ GLOB deformation_dependent_porosity_pcs_0_ts_*.vtu epsilon epsilon 1e-14 0
+ GLOB deformation_dependent_porosity_pcs_0_ts_*.vtu velocity velocity 5e-14 0
+ GLOB deformation_dependent_porosity_pcs_0_ts_*.vtu porosity porosity 5e-14 1e-15
+ GLOB deformation_dependent_porosity_pcs_0_ts_*.vtu porosity_avg porosity_avg 1e-14 1e-15
+)
#PETSc
AddTest(
NAME Parallel_RichardsMechanics_RichardsFlow_2d_richardsflow
diff --git a/Tests/Data/RichardsMechanics/deformation_dependent_porosity.prj b/Tests/Data/RichardsMechanics/deformation_dependent_porosity.prj
new file mode 100644
index 0000000000000000000000000000000000000000..6810b7220c6de8d96bc6b06020c0886b1e7ea60b
--- /dev/null
+++ b/Tests/Data/RichardsMechanics/deformation_dependent_porosity.prj
@@ -0,0 +1,340 @@
+<?xml version="1.0" encoding="ISO-8859-1"?>
+<OpenGeoSysProject>
+ <mesh>square_1x1_quad8_1e2.vtu</mesh>
+ <geometry>square_1x1.gml</geometry>
+ <processes>
+ <process>
+ <name>RM</name>
+ <type>RICHARDS_MECHANICS</type>
+ <integration_order>3</integration_order>
+ <dimension>2</dimension>
+ <!-- Keep for testing
+ <jacobian_assembler>
+ <type>CentralDifferences</type>
+ <component_magnitudes>1e5 1e5 1e5 1e5 1e-5 1e-5 1e-5 1e-5 1e-5 1e-5 1e-5 1e-5 1e-5 1e-5 1e-5 1e-5 1e-5 1e-5 1e-5 1e-5</component_magnitudes>
+ <relative_epsilons>1e-8 1e-8 1e-8 1e-8 1e-8 1e-8 1e-8 1e-8 1e-8 1e-8 1e-8 1e-8 1e-8 1e-8 1e-8 1e-8 1e-8 1e-8 1e-8 1e-8</relative_epsilons>
+ </jacobian_assembler>
+ -->
+ <constitutive_relation>
+ <type>LinearElasticIsotropic</type>
+ <youngs_modulus>E</youngs_modulus>
+ <poissons_ratio>nu</poissons_ratio>
+ </constitutive_relation>
+ <process_variables>
+ <displacement>displacement</displacement>
+ <pressure>pressure</pressure>
+ </process_variables>
+ <secondary_variables>
+ <secondary_variable internal_name="sigma" output_name="sigma"/>
+ <secondary_variable internal_name="epsilon" output_name="epsilon"/>
+ <secondary_variable internal_name="velocity" output_name="velocity"/>
+ <secondary_variable internal_name="saturation" output_name="saturation"/>
+ <secondary_variable internal_name="porosity" output_name="porosity"/>
+ </secondary_variables>
+ <specific_body_force>0 0</specific_body_force>
+ </process>
+ </processes>
+ <media>
+ <medium>
+ <phases>
+ <phase>
+ <type>AqueousLiquid</type>
+ <properties>
+ <property>
+ <name>bulk_modulus</name>
+ <type>Constant</type>
+ <value>1</value>
+ </property>
+ <property>
+ <name>viscosity</name>
+ <type>Constant</type>
+ <value>1</value>
+ </property>
+ <property>
+ <name>density</name>
+ <type>Constant</type>
+ <value>1</value>
+ </property>
+ </properties>
+ </phase>
+ <phase>
+ <type>Solid</type>
+ <properties>
+ <property>
+ <name>bulk_modulus</name>
+ <type>Constant</type>
+ <value>10</value>
+ </property>
+ <property>
+ <name>biot_coefficient</name>
+ <type>Constant</type>
+ <value>1</value>
+ </property>
+ <property>
+ <name>density</name>
+ <type>Constant</type>
+ <value>1</value>
+ </property>
+ <property>
+ <name>porosity</name>
+ <type>PorosityFromMassBalance</type>
+ <initial_porosity>phi0</initial_porosity>
+ </property>
+ <property>
+ <name>permeability</name>
+ <type>Constant</type>
+ <value>1</value>
+ </property>
+ </properties>
+ </phase>
+ </phases>
+ <properties>
+ <property>
+ <name>reference_temperature</name>
+ <type>Constant</type>
+ <value>293.15</value>
+ </property>
+ <property>
+ <name>saturation</name>
+ <type>Constant</type>
+ <value>1</value>
+ </property>
+ <property>
+ <name>relative_permeability</name>
+ <type>Constant</type>
+ <value>1</value>
+ </property>
+ </properties>
+ </medium>
+ </media>
+ <time_loop>
+ <processes>
+ <process ref="RM">
+ <nonlinear_solver>nonlinear_solver</nonlinear_solver>
+ <convergence_criterion>
+ <type>PerComponentDeltaX</type>
+ <norm_type>NORM2</norm_type>
+ <abstols>1e-14 1e-14 1e-14</abstols>
+ </convergence_criterion>
+ <time_discretization>
+ <type>BackwardEuler</type>
+ </time_discretization>
+ <time_stepping>
+ <type>FixedTimeStepping</type>
+ <t_initial>0</t_initial>
+ <t_end>4</t_end>
+ <timesteps>
+ <pair>
+ <repeat>20</repeat>
+ <delta_t>.01</delta_t>
+ </pair>
+ <pair>
+ <repeat>8</repeat>
+ <delta_t>.1</delta_t>
+ </pair>
+ <pair>
+ <repeat>20</repeat>
+ <delta_t>.01</delta_t>
+ </pair>
+ <pair>
+ <repeat>8</repeat>
+ <delta_t>.1</delta_t>
+ </pair>
+ <pair>
+ <repeat>20</repeat>
+ <delta_t>.01</delta_t>
+ </pair>
+ <pair>
+ <repeat>8</repeat>
+ <delta_t>.1</delta_t>
+ </pair>
+ <pair>
+ <repeat>20</repeat>
+ <delta_t>.01</delta_t>
+ </pair>
+ <pair>
+ <repeat>8</repeat>
+ <delta_t>.1</delta_t>
+ </pair>
+ </timesteps>
+ </time_stepping>
+ </process>
+ </processes>
+ <output>
+ <type>VTK</type>
+ <prefix>deformation_dependent_porosity</prefix>
+ <timesteps>
+ <pair>
+ <repeat>1000</repeat>
+ <each_steps>1</each_steps>
+ </pair>
+ </timesteps>
+ <variables>
+ <variable>displacement</variable>
+ <variable>pressure</variable>
+ <variable>sigma</variable>
+ <variable>epsilon</variable>
+ <variable>velocity</variable>
+ <variable>saturation</variable>
+ <variable>porosity</variable>
+ </variables>
+ </output>
+ </time_loop>
+ <parameters>
+ <!-- Mechanics -->
+ <parameter>
+ <name>E</name>
+ <type>Constant</type>
+ <value>1</value>
+ </parameter>
+ <parameter>
+ <name>nu</name>
+ <type>Constant</type>
+ <value>.3</value>
+ </parameter>
+ <parameter>
+ <name>phi0</name>
+ <type>Constant</type>
+ <value>0.5</value>
+ </parameter>
+ <!-- Model parameters -->
+ <parameter>
+ <name>displacement0</name>
+ <type>Constant</type>
+ <values>0 0</values>
+ </parameter>
+ <parameter>
+ <name>p0</name>
+ <type>Constant</type>
+ <value>0</value>
+ </parameter>
+ <parameter>
+ <name>dirichlet0</name>
+ <type>Constant</type>
+ <values>0</values>
+ </parameter>
+ <parameter>
+ <name>maximum_pressure</name>
+ <type>Constant</type>
+ <value>0.1</value>
+ </parameter>
+ <parameter>
+ <name>maximum_displacement</name>
+ <type>Constant</type>
+ <value>-0.1</value>
+ </parameter>
+ <parameter>
+ <name>pressureRamp</name>
+ <type>CurveScaled</type>
+ <curve>pressure</curve>
+ <parameter>maximum_pressure</parameter>
+ </parameter>
+ <parameter>
+ <name>displacementRamp</name>
+ <type>CurveScaled</type>
+ <curve>displacement</curve>
+ <parameter>maximum_displacement</parameter>
+ </parameter>
+ </parameters>
+ <curves>
+ <curve>
+ <name>displacement</name>
+ <coords>0 1 2 3 4</coords>
+ <values>0 1 1 1 1</values>
+ </curve>
+ <curve>
+ <name>pressure</name>
+ <coords>0 1 2 3 4</coords>
+ <values>0 0 0 1 1</values>
+ </curve>
+ </curves>
+ <process_variables>
+ <process_variable>
+ <name>displacement</name>
+ <components>2</components>
+ <order>2</order>
+ <initial_condition>displacement0</initial_condition>
+ <boundary_conditions>
+ <boundary_condition>
+ <geometrical_set>square_1x1_geometry</geometrical_set>
+ <geometry>left</geometry>
+ <type>Dirichlet</type>
+ <component>0</component>
+ <parameter>dirichlet0</parameter>
+ </boundary_condition>
+ <boundary_condition>
+ <geometrical_set>square_1x1_geometry</geometrical_set>
+ <geometry>bottom</geometry>
+ <type>Dirichlet</type>
+ <component>1</component>
+ <parameter>dirichlet0</parameter>
+ </boundary_condition>
+ <boundary_condition>
+ <geometrical_set>square_1x1_geometry</geometrical_set>
+ <geometry>top</geometry>
+ <type>Dirichlet</type>
+ <component>1</component>
+ <parameter>displacementRamp</parameter>
+ </boundary_condition>
+ <boundary_condition>
+ <geometrical_set>square_1x1_geometry</geometrical_set>
+ <geometry>right</geometry>
+ <type>Dirichlet</type>
+ <component>0</component>
+ <parameter>displacementRamp</parameter>
+ </boundary_condition>
+ </boundary_conditions>
+ </process_variable>
+ <process_variable>
+ <name>pressure</name>
+ <components>1</components>
+ <order>1</order>
+ <initial_condition>p0</initial_condition>
+ <boundary_conditions>
+ <boundary_condition>
+ <geometrical_set>square_1x1_geometry</geometrical_set>
+ <geometry>top</geometry>
+ <type>Dirichlet</type>
+ <parameter>pressureRamp</parameter>
+ </boundary_condition>
+ <boundary_condition>
+ <geometrical_set>square_1x1_geometry</geometrical_set>
+ <geometry>right</geometry>
+ <type>Dirichlet</type>
+ <parameter>pressureRamp</parameter>
+ </boundary_condition>
+ <boundary_condition>
+ <geometrical_set>square_1x1_geometry</geometrical_set>
+ <geometry>bottom</geometry>
+ <type>Dirichlet</type>
+ <parameter>pressureRamp</parameter>
+ </boundary_condition>
+ <boundary_condition>
+ <geometrical_set>square_1x1_geometry</geometrical_set>
+ <geometry>left</geometry>
+ <type>Dirichlet</type>
+ <parameter>pressureRamp</parameter>
+ </boundary_condition>
+ </boundary_conditions>
+ </process_variable>
+ </process_variables>
+ <nonlinear_solvers>
+ <nonlinear_solver>
+ <name>nonlinear_solver</name>
+ <type>Newton</type>
+ <max_iter>100</max_iter>
+ <linear_solver>general_linear_solver</linear_solver>
+ </nonlinear_solver>
+ </nonlinear_solvers>
+ <linear_solvers>
+ <linear_solver>
+ <name>general_linear_solver</name>
+ <eigen>
+ <solver_type>BiCGSTAB</solver_type>
+ <precon_type>DIAGONAL</precon_type>
+ <max_iteration_step>10000</max_iteration_step>
+ <error_tolerance>1e-16</error_tolerance>
+ </eigen>
+ </linear_solver>
+ </linear_solvers>
+</OpenGeoSysProject>
diff --git a/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_107_t_3.500000.vtu b/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_107_t_3.500000.vtu
new file mode 100644
index 0000000000000000000000000000000000000000..dd01912f080470c7c700ae351b72eb0798044de8
--- /dev/null
+++ b/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_107_t_3.500000.vtu
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:709f8e22fb7554d0256cc95fd405b53eb15fa7747fc1becd235ca31de743dd69
+size 36135
diff --git a/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_112_t_4.000000.vtu b/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_112_t_4.000000.vtu
new file mode 100644
index 0000000000000000000000000000000000000000..e76337a19fe432db03aa57f7882f3a8243de5888
--- /dev/null
+++ b/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_112_t_4.000000.vtu
@@ -0,0 +1,3 @@
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diff --git a/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_23_t_0.500000.vtu b/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_23_t_0.500000.vtu
new file mode 100644
index 0000000000000000000000000000000000000000..344013f70515d9c928f5a1095025dbc53d9edbbf
--- /dev/null
+++ b/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_23_t_0.500000.vtu
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
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diff --git a/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_28_t_1.000000.vtu b/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_28_t_1.000000.vtu
new file mode 100644
index 0000000000000000000000000000000000000000..6c8f924b7a6202cdd4c0719888f7910ead97c662
--- /dev/null
+++ b/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_28_t_1.000000.vtu
@@ -0,0 +1,3 @@
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+size 34055
diff --git a/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_51_t_1.500000.vtu b/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_51_t_1.500000.vtu
new file mode 100644
index 0000000000000000000000000000000000000000..1396e73c8a158a5cb3e0ee2760b5d5921a95da64
--- /dev/null
+++ b/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_51_t_1.500000.vtu
@@ -0,0 +1,3 @@
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diff --git a/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_56_t_2.000000.vtu b/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_56_t_2.000000.vtu
new file mode 100644
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--- /dev/null
+++ b/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_56_t_2.000000.vtu
@@ -0,0 +1,3 @@
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diff --git a/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_79_t_2.500000.vtu b/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_79_t_2.500000.vtu
new file mode 100644
index 0000000000000000000000000000000000000000..8e01971158e0dcac79991a0d04715ead5429cbfa
--- /dev/null
+++ b/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_79_t_2.500000.vtu
@@ -0,0 +1,3 @@
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diff --git a/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_84_t_3.000000.vtu b/Tests/Data/RichardsMechanics/deformation_dependent_porosity_pcs_0_ts_84_t_3.000000.vtu
new file mode 100644
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