Data from in situ X-ray CT imaging of transient water retention experiments with cyclic drainage and imbibition: ================================================================================================================ Metadata, describing the context of the experiments and the scientific data made available in this repository. 0. Context of the data: ----------------------- This data set contains research data related to the article "In situ X-ray CT imaging of transient water retention experiments with cyclic drainage and imbibition" in the journal Open Geomechanics. The research data include 3D CT images acquired during cyclic drainage and imbibition of a sand specimen in a transient in situ water retention experiment that was run in the X-ray tomograph at Laboratoire 3SR at Univ. Grenoble Alpes. Besides the CT images, also data from the multiphase image analysis as well as macroscopic water retention data, measured in parallel to the CT scans, are published. The experimental set-up used in the experiments is fully described in the following publication: Milatz, M. (2020): An automated testing device for continuous measurement of the hysteretic water retention curve of granular media. In: Acta Geotechnica 8 (15). DOI: 10.1007/s11440-020-00922-y. The data in this repository supplements the following main publication in the journal Open Geomechanics, focussing on the analysis of CT data: Milatz, M., Andò, E., Viggiani, G., and Mora, S. (2022): In situ X-ray CT imaging of transient water retention experiments with cyclic drainage and imbibition. In: Open Geomechanics 3(5). DOI: 10.5802/ogeo.13. 1. Water retention data (measured with Raspberry Pi set-up): ------------------------------------------------------------ The following data files contain the measured water retention data as well as information about the experimental settings: WRC_Test_HH_Sand_21_07_2019_002.csv -> Water retention data Test_info_WRC_Test_HH_Sand_21_07_2019_002.csv -> Test info file The macroscopic water retention curve can be visualised with the following Python script: Plot_WRC.py -> Script for visualising the macroscopic water retention curve The script creates the figures s_vs_t.pdf, Sr_vs_t.pdf, and WRC.pdf. 2. Measured interfacial areas and contact lines: ------------------------------------------------ The following data files contain the air-water and solid-water interfacial areas as well as specific contact line measured in a central cubic subvolume of 800x800x800 px in the reconstructed and segmented CT data: Interfacial_area_data.txt -> Measured interfacial areas and specific interfacial areas Contact_line_data.txt -> Measured contact lines and specific contact lines The interfacial areas and contact lines can be visualised with the following Python script: Plot_Interfacial_Areas_and_Contact_Line.py -> Script for visualising interfacial areas and contact lines The script creates the figures a_nw_vs_Sr_CT.pdf, a_sw_vs_Sr_CT.pdf, a_nw_vs_s_CT.pdf, a_sw_vs_s_CT.pdf, l_c_vs_Sr_CT.pdf, and l_c_vs_s_CT.pdf. 3. Measured contact angles and radii of curvature: -------------------------------------------------- The following data file contains the measured contact angles and radii of curvature: Contact_angle_and_radii_of_curvature_data.txt -> Measured contact angles and radii of curvature The contact angles and radii of curvature can be visualised with the following Python script: Plot_contact_angles_and_radii_of_curvature.py -> Script for visualising the contact angles and radii of curvature and for evaluation of capillary pressure by means of the Young-Laplace equation The script creates the figures contact_angles_vs_steps_CT.pdf, histogram_of_contact_angles_CT.pdf, capillary_pressure_vs_steps_CT.pdf, capillary_pressure_vs_contact_angle_regression_CT.pdf, radius_of_curvature_vs_steps_CT.pdf, and radius_of_curvature_vs_contact_angle_CT.pdf. 4. Image data: -------------- The following tiff-files represent the reconstructed greyscale images from the initial (00) and subsequent CT scans (01-19) during cyclic drainage and imbibition: CT_data_sand_00.tif -> Initial water-saturated state CT_data_sand_01.tif CT_data_sand_02.tif CT_data_sand_03.tif CT_data_sand_04.tif CT_data_sand_05.tif CT_data_sand_06.tif CT_data_sand_07.tif CT_data_sand_08.tif CT_data_sand_09.tif CT_data_sand_10.tif CT_data_sand_11.tif CT_data_sand_12.tif CT_data_sand_13.tif CT_data_sand_14.tif CT_data_sand_15.tif CT_data_sand_16.tif CT_data_sand_17.tif CT_data_sand_18.tif CT_data_sand_19.tif The following tiff-files represent the segmented images from the initial (00) and subsequent CT scans (01-19) during cyclic drainage and imbibition: CT_data_sand_segmented_00.tif -> Initial water-saturated state CT_data_sand_segmented_01.tif CT_data_sand_segmented_02.tif CT_data_sand_segmented_03.tif CT_data_sand_segmented_04.tif CT_data_sand_segmented_05.tif CT_data_sand_segmented_06.tif CT_data_sand_segmented_07.tif CT_data_sand_segmented_08.tif CT_data_sand_segmented_09.tif CT_data_sand_segmented_10.tif CT_data_sand_segmented_11.tif CT_data_sand_segmented_12.tif CT_data_sand_segmented_13.tif CT_data_sand_segmented_14.tif CT_data_sand_segmented_15.tif CT_data_sand_segmented_16.tif CT_data_sand_segmented_17.tif CT_data_sand_segmented_18.tif CT_data_sand_segmented_19.tif