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While Menu Selections 8 to 10 could possibly be used to distribute phases amongst fly ash particles as well as cement particles, Menu Selection 11 has been developed specifically for the distribution of phases amongst fly ash particles, under two simplifying cases. In the first case, the particles are assumed to be monophase and the particles are randomly assigned phases to achieve the desired phase volume fractions. In the second, the phases are simply randomly distributed amongst all of the pixels identified as fly ash in the 3-D particle microstructure. This would imply a very fine and relatively uniform distribution of the fly ash phases amongst the individual particles. Currently, the following phases are considered for distribution amongst the fly ash particles: aluminosilicate, calcium aluminodisilicate, silica, anhydrite, calcium chloride, tricalcium aluminate, and an inert phase. Reactions between these phases and the main components of cement have been incorporated into the current version of the cement hydration model [1, 10].
To execute Menu Selection 11, the user provides a random number seed, selects whether distribution is to be done on a random particle or a random pixel basis, and fills in the remainder of the form shown in Figure 13. The user must provide the original microstructure and particle microstructure filenames, the name of an output file to hold the processed microstructure, the number of fly ash pixels in the 3-D microstructure (can be determined using Menu Selection 9 above), the desired volume fractions for the various fly ash phases, and their e-mail address. The particle microstructure image is needed for the case where the phases are distributed randomly amongst the particles, one phase per particle. When fly ash particles are placed during the creation of a microstructure (Menu Selection 3), they are assigned a phase ID of 26. Thus, when using Menu Selection 9, the user must be sure to note the volume count for phase ID 26 and use it as the correct value for the fly ash count in the form shown in Figure 13.
Figure 13: Form to specify inputs to be used in distributing the phases amongst the fly ash particles.