Issue 41

H. Šimonová et alii, Frattura ed Integrità Strutturale, 41 (2017) 211-219; DOI: 10.3221/IGF-ESIS.41.29 214 The measured values of distances between individual grains of aggregate are shown in Fig. 2. These distances, even though they don’t correspond to the idealized concept of a thickness and shape of the ITZ, come from real measurements. These measurements prove that the formation of the discrete zone (ITZ) with constant thickness around grain of aggregate is practically impossible. Therefore, the distances between these individual grains and the larger one, or more precisely their mean values, are considered as the thicknesses of the ITZ in following study [2, 18]. Figure 1 : Microstructure of fracture surface at aggregate–cement paste interface by detection of SE with magnification 5000×, specimens 04042016 (left) and 09052016. Figure 2 : Distances between grains of aggregate measured using SEM with detection of SE, specimens 04042016 (left, magnification 70×) and 09052016 (magnification 60×).