Triaxial Test Evaluation Tool

With this evaluation tool you can check and interpret the results of a modified geotechnical triaxial test. With this appliance it is possible to confine a probe, rise the axial stress and measure the permeability of the probe at all stages. The tool was developed as part of a joint project called MERID (Microstructural Influence on Reservoir Integrity at Variable Hydromechanical Conditions) funded by the German Federal Ministry of Education and Research as part of GEO:N Project (Geoforschung für Nachhaltigkeit) to evaluate the results of a special assembled large triaxial cell. This tool consists of a backend and a frontend both assembled in MathWorks Matlab. The backend creates a connection to a MySQL-Database where the results of all experiments stored.

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Features

Frontend (GUI)

• List and overview of all experiments in database
• Keep rock/soil parameters always in view
• Check experiment descriptions and additional comments
• Get an overview of important parameters and their connection
• Show experiment's time log related to experiments data
• Change integration time step for permeability calculation
• Plot graphs with variable x-axis and two possible y-axes
• Compare to different/independent experiments
• Export graphs easily as raster graphics (1200 DPI) or vector graphics

Backend

• Class oriented programming in Matlab
• Connection to MySQL database
• Interface between frontend (GUI) and MySQL database
• Separate classes for handling experiments metadata ExperimentsMetaData, measured values ExperimentsData, rock/soil related data ExperimentsSpecimenData, MySQL database connection MeridDB, interface to frontend (GUI) TriaxTestHandler
• Measured data cleansing like filtering NaN values
• Calculating permeability and permeability coefficient according to fluid (water) properties with help of isantosruiz' water-properties repository.

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Requirements

• Matlab Version 2020a or newer
• Matlab Curve Fitting Toolbox for permeability calculations
• JDBC MySQL Connector included in Matlab javaclasspath (dynamic or static)
• Configured MySQL database engine (a script creating the database skeleton is attached in this repository) which includes all triaxial test data sets

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Setup

• Have a running MathWorks Matlab 2019b or higher engine with installed curve fitting toolbox.
• Have a running MySQL engine with a database according to the needs of this tool. To create a valid database you can use the batch file in this repository.
• Download JDBC MySQL Connector (platform independent version) to your local machine.
• Add JDBC MySQL Connector to javaclasspath dynamic part

>> javaaddpath('/your_folder/mysql-connector-java-8.0.20.jar')

• Check if adding was successful

>> javaclasspath
  
  /some_other_folder/some_file.jar
  
      DYNAMIC JAVA PATH

  /your_folder/mysql-connector-java-8.0.20.jar

• Download the latest release of Triaxial Test Evaluation Tool to your local machine and include the submodule water-properties additionally. As an alternative you can clone the repository via git clone --recurse-submodules --remote-submodules https://github.com/froido/triaxial_test_evaluation_tool.git
• Run GUI.mlapp

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Usage

1. Adding triaxial test data sets to the database
2. Start the Triaxial Test Evaluation Tool via GUI.mlapp.
3. Select a main experiment from the shown list.
4. Evaluate your test results and enjoy.

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Additional Hints

• Matlab has often problems with the timezone set in Oracle MySQL database under Windows systems. CEST (German: MESZ) is unknown for Matlab, which leads to an error. Set the timezone manually to e.g. +02:00.

SET GLOBAL time_zone = '+02:00';

• Due to very big data sets the global buffer size shall be extended in MySQL database to e.g. 4 gigabyte

SET GLOBAL innodb_buffer_pool_size=4294967296;

• After a couple of changes were performed in the graphs, the GUI of Matlab lags sometimes for unknown reasons. You have two options: kill or wait.

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Support

Reach out to me at one of the following places!

• Website at www.geotechnik.rwth-aachen.de

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License

This project is licensed under the GNU General Public License v3.0 - see LICENSE.md file for details

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Thanks