PSI - Issue 43

Vlastimil Bílek et al. / Procedia Structural Integrity 43 (2023) 107–112 Author name / Structural Integrity Procedia 00 (2022) 000 – 000

111

5

0.5F

0.5W

0.4F

0.4W

0.3F

0.3W

Fig. 1. Examples of CT imaging of concretes with w/c =0.5, 0.4 and 0.3 stored 28 days in foil (F) or in water (W).

set to a level that allowed for the segmentation of tomographic volumes, especially the volume of bubble pores and major separation cracks; see Table 4 for the resulting porosity values. The second and third threshold values of voxels were set so that the part of the pore space belonging to the volume of less pronounced separation cracks in the concrete bodies was segmented. The values in Table 4 show three basic tendencies: - similarly cured concretes with lower w/c show lower porosity than those with a higher w/c ; - water-cured specimens show lower porosity than foil-cured specimens; - the higher the threshold value, the higher the porosity is.