 <OpenGeoSysProject>

   <meshes>

     <mesh axially_symmetric="true">model.vtu</mesh>

     <mesh axially_symmetric="true">geometry_left.vtu</mesh>

     <mesh axially_symmetric="true">geometry_right.vtu</mesh>

     <mesh axially_symmetric="true">geometry_top.vtu</mesh>

     <mesh axially_symmetric="true">geometry_bottom.vtu</mesh>

   </meshes>

   <processes>

     <process>

       <name>SD</name>

       <type>SMALL_DEFORMATION</type>

       <integration_order>2</integration_order>

       <constitutive_relation>

         <type>MFront</type>

         <behaviour>GuentherSalzerDilatancy_semi_expl</behaviour>

         <material_properties>

           <material_property name="YoungModulus" parameter="YoungModulus" />

           <material_property name="PoissonRatio" parameter="PoissonRatio" />

         </material_properties>

       </constitutive_relation>

       <specific_body_force>0 0</specific_body_force>

       <process_variables>

         <process_variable>displacement</process_variable>

       </process_variables>

       <secondary_variables>

         <secondary_variable internal_name="sigma" output_name="sigma" />

         <secondary_variable internal_name="epsilon" output_name="epsilon" />

         <secondary_variable internal_name="ElasticStrain" output_name="ElasticStrain" />

         <secondary_variable internal_name="HardeningStrain" output_name="HardeningStrain" />

         <secondary_variable internal_name="DilatancyStrain" output_name="DilatancyStrain" />

         <secondary_variable internal_name="DilatancyWork" output_name="DilatancyWork" />

       </secondary_variables>

       <reference_temperature>T_ref</reference_temperature>

       <initial_stress>sig0</initial_stress>

     </process>

   </processes>

   <time_loop>

     <processes>

       <process ref="SD">

         <nonlinear_solver>basic_newton</nonlinear_solver>

         <convergence_criterion>

           <type>DeltaX</type>

           <norm_type>NORM2</norm_type>

           <abstol>1e-8</abstol>

         </convergence_criterion>

         <time_discretization>

           <type>BackwardEuler</type>

         </time_discretization>

         <time_stepping>

           <type>IterationNumberBasedTimeStepping</type>

           <t_initial>0</t_initial>

           <t_end>0.34</t_end>

           <initial_dt>1e-2</initial_dt>

           <minimum_dt>1.e-6</minimum_dt>

           <maximum_dt>1.e-2</maximum_dt>

           <number_iterations>1 5 10 15</number_iterations>

           <multiplier>1.2 1.05 0.8 0.6</multiplier>

         </time_stepping>

       </process>

     </processes>

     <output>

       <type>VTK</type>

       <prefix>triaxial_test_output</prefix>

       <suffix>t{:time}</suffix>

       <timesteps>

         <pair>

           <repeat>10000</repeat>

           <each_steps>100</each_steps>

         </pair>

       </timesteps>

       <variables>

         <variable>displacement</variable>

         <variable>sigma</variable>

         <variable>epsilon</variable>

       </variables>

     </output>

   </time_loop>

   <media>

     <medium>

       <phases>

         <phase>

           <type>Solid</type>

           <properties>

             <property>

               <name>density</name>

               <type>Constant</type>

               <value>0</value>

             </property>

           </properties>

         </phase>

       </phases>

     </medium>

   </media>

   <parameters>

     <parameter>

       <name>sig0</name>

       <type>Function</type>

       <expression>-1</expression>

       <expression>-1</expression>

       <expression>-1</expression>

       <expression>0</expression>

     </parameter>

     <parameter>

       <name>YoungModulus</name>

       <type>Constant</type>

       <value>25e4</value>

     </parameter>

     <parameter>

       <name>PoissonRatio</name>

       <type>Constant</type>

       <value>0.27</value>

     </parameter>

     <parameter>

       <name>T_ref</name>

       <type>Constant</type>

       <value>293.15</value>

     </parameter>

     <parameter>

       <name>displacement0</name>

       <type>Constant</type>

       <values>0 0</values>

     </parameter>

     <parameter>

       <name>zero</name>

       <type>Constant</type>

       <value>0.0</value>

     </parameter>

     <parameter>

       <name>sig_conf</name>

       <type>Constant</type>

       <value>-1.0</value>

     </parameter>

     <parameter>

       <name>axial_compression</name>

       <type>CurveScaled</type>

       <curve>ax_loading_curve</curve>

       <parameter>disp_top</parameter>

     </parameter>

     <parameter>

       <name>disp_top</name>

       <type>Constant</type>

       <value>-1</value>

     </parameter>

   </parameters>

   <curves>

     <curve>

       <name>ax_loading_curve</name>

       <coords>0.0 0.34</coords>

       <values>0.0 20.0</values>

     </curve>

   </curves>

   <process_variables>

     <process_variable>

       <name>displacement</name>

       <components>2</components>

       <order>1</order>

       <initial_condition>displacement0</initial_condition>

       <boundary_conditions>

         <boundary_condition>

           <mesh>geometry_left</mesh>

           <type>Dirichlet</type>

           <component>0</component>

           <parameter>zero</parameter>

         </boundary_condition>

         <boundary_condition>

           <mesh>geometry_bottom</mesh>

           <type>Dirichlet</type>

           <component>1</component>

           <parameter>zero</parameter>

         </boundary_condition>

         <boundary_condition>

           <mesh>geometry_top</mesh>

           <type>Dirichlet</type>

           <component>1</component>

           <parameter>axial_compression</parameter>

         </boundary_condition>

         <boundary_condition>

           <mesh>geometry_right</mesh>

           <type>Neumann</type>

           <component>0</component>

           <parameter>sig_conf</parameter>

         </boundary_condition>

       </boundary_conditions>

     </process_variable>

   </process_variables>

   <nonlinear_solvers>

     <nonlinear_solver>

       <name>basic_newton</name>

       <type>Newton</type>

       <max_iter>60</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>SparseLU</solver_type>

         <scaling>true</scaling>

       </eigen>

     </linear_solver>

   </linear_solvers>

   <test_definition>

     <vtkdiff>

       <file>triaxial_test_output_t_0.340000.vtu</file>

       <field>displacement</field>

       <absolute_tolerance>3e-8</absolute_tolerance>

       <relative_tolerance>0</relative_tolerance>

     </vtkdiff>

     <vtkdiff>

       <file>triaxial_test_output_t_0.340000.vtu</file>

       <field>sigma</field>

       <absolute_tolerance>9e-2</absolute_tolerance>

       <relative_tolerance>0</relative_tolerance>

     </vtkdiff>

   </test_definition>

 </OpenGeoSysProject>