gut-aachen / triaxial_test_evaluation_tool

Evaluate results of a modified geotechnical triaxial test with permeability measurement

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.
• Using BrewerMap from DrosteEffect which provides all ColorBrewer colorschemes (designed by Cynthia A. Brewer) for MATLAB.

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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.gut.rwth-aachen.de
• ORCID
• XING

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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

triaxial_test_evaluation_tool's Issues

Loading (multiple) experiments in background

Adding an option to load (multiple) experiments in the background, while GUI is still online and usable.

"Export all graphs button" not working

"Export all graphs" button does

1. not export all graphs: merge is missing
2. overwrites some graphs if they are showing equal axes, i.e. permeability-runtime

Data time interval for both y-axes equal

If a graph is displayed with two y-axes, of which one axis represents the permeability, display problems occur.

Example:

y1: Permeability (5 min) and y2: Compaction Pressure

Desired: On the y1 axis, permeability should be calculated and displayed at 5-minute intervals, and on the y2 axis, all available data should be displayed at the minimum interval (1 sec).

Is: As soon as a permeability is assigned to a y-axis, the specified time interval is used for both y-axes (y1/y2).