The inter-connectivity of the capillary pores is controlled by pore necks with dimensions between 1nm and 1000nm, while the size of air voids ranges from micrometers to millimeters. Hence, their examination requires microscopic imaging at different scales. Since, moreover, the three dimensional context for the percolation of the pores is decisive, 3D microscopy is required.
3D microscopy of cement pastes, cements and mortars is achieved by means of focused ion beam nanotomography (FIB-nt, [Holzer et.al., 2004]) in the 10 - 1000nm range, by synchrotron radiation micro computer tomography (SRmCT) in the 100nm - 10mm range, .and by conventional micro computer tomography (mCT) in the 10mm 1mm range. Internal water transport process (such as internal curing) within cementitious materials can be observed with relatively coarse time- and lengthscale resolutions using neutron microtomgoraphy.