Figure 3

The reconstructed attenuation coefficient μ (a–c) and scattering coefficient ε (d–f) of a slice through the center of the sample is shown after 2.3 (a,d), 6.9 (b,e) and 11.5 hours (c,f). A change of ε is observed in the cement and the limestone grains of type 1. The temporal evolution of μ and ε for the cement and each grain throughout the whole experiment is depicted in the three graphs. The scattering coefficient of the cement paste in the vicinity of each grain shows a clear logistic decline over time (pink and green curve in each individual graph) which has been reported before²². In contrast to K2T, K3T, K2B and K3B, ε increases for the two limestone grains K1T and K1B (light-blue and orange curve in each individual graph). The attenuation coefficient remains constant for the cement paste and each limestone grain (dashed curves in each individual graph). The small dip and bump in the signals between 20–25 hours is related to an instability in the high voltage generator of the tube.