Deformation analysis in civil engineering material testing

Doctoral candidate: Frank Liebold

This project is part of a Research Training Group (GRK 2250/1, part C1) and it is funded by the German Research Council (DFG). The project deals with photogrammetric deformation analysis. The focus is on the detection and description of cracks. In addition to the analysis of monocular image sequences with high resolution, a high speed stereo system is available in order to observe dynamic processes with high temporal resolution.

For the analysis of image sequences, first, a displacement field is computed by tracking surface points using matching methods for each epoch. As reference, an image or stereo pair of the specimen under zero-load is used. Deformations including cracks are detected by the geometrical analysis a of triangle mesh (the vertices are the matching points).

In addition, the analysis of stereo image sequences are done. The following video shows the analysis of a torsion test. The computations is done with the help of a trianglular network. In the upper part, there is a color-coded visualisation of the norm of the 2D relative translation vector. In the middle, the 3D relative translation vectors are depicted in magenta for the deformed triangles. The lower part shows the components of the 3D crack opening vectors.

 Link to project webpage: https://www.grk2250.de/

Link to the GRK webpage of IfB

Publications 2021

• Hering, M., Scheerer, S., Curbach, M., Vo, D., M., P., Sennewald, C., Cherif, C., Liebold, F., Maas, H.-G., Qinami, A., Steinke, C., Fuchs, A., Kaliske, M., Curosu, I., Mechtcherine, V. (2021):
  Impaktsicherheit von Baukonstruktionen durch mineralisch‐gebundene Komposite: Bauteilebene. Beton- und Stahlbau, 116(1), 58-67, https://doi.org/10.1002/best.202000067

Publications 2020

• Gong, T., Curosu, I., Liebold, F., Vo, D., M., P., Zierold, K., Maas, H.-G., Cherif, C., Mechtcherine, V. (2020):
  Tensile Behavior of High-Strength, Strain-Hardening Cement-Based Composites (HS-SHCC) Reinforced with Continuous Textile Made of Ultra-High-Molecular-Weight Polyethylene. Materials, 13(24), https://doi.org/10.3390/ma13245628.
• Liebold, F., Heravi, A., A., Mosig, O., Curbach, M., Mechtcherine, V., Maas, H.-G. (2020):
  Crack Propagation Velocity Determination by High-speed Camera Image Sequence Processing. Materials, 13(19), https://doi.org/10.3390/ma13194415.
• Liebold, F., Maas, H.-G., Deutsch, J. (2020):
  Photogrammetric determination of 3D crack opening vectors from 3D displacement fields. ISPRS Journal of Photogrammetry and Remote Sensing, 164, 1-10, https://doi.org/10.1016/j.isprsjprs.2020.03.019.
• Liebold, F., Maas, H.-G. (2020):
  Strategy for Crack Width Measurement of Multiple Crack Patterns in Civil Engineering Material Testing Using a Monocular Image Sequence Analysis. PFG -

  Journal of Photogrammetry, Remote Sensing and Geoin­formation Science, 88(3), 219-238, https://doi.org/10.1007/s41064-020-00103-2.

Publications 2019

• Liebold, F., Maas, H.-G., Heravi, A., A. (2019):
  Crack Width Measurement for Non-planar Surfaces by Triangle Mesh Analysis in Civil Engineering Material Testing. ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, XLII-2/W18, 107–113, https://doi.org/10.5194/isprs-archives-XLII-2-W18-107-2019.
  (Link)

Publications 2018

• Liebold, F., Maas, H.-G. (2018):
  Sub-pixel accuracy crack width determination on concrete beams in load tests by triangle mesh geometry analysis. ISPRS Ann. Photogramm. Remote Sens. Spatial Inf. Sci., IV-2, 193-200, https://doi.org/10.5194/isprs-annals-IV-2-193-2018.

Publications 2016

• Liebold, F., Maas, H.-G. (2016):
  Advanced spatio-temporal filtering techniques for photogrammetric image sequence analysis in civil engineering material testing. ISPRS Journal of Photogrammetry and Remote Sensing, 111,13-21, https://doi.org/10.1016/j.isprsjprs.2015.10.013.