To compile version 2.0 of CEMHYD3D a typical command line on a UNIX
workstation might be:
cc disrealnew.c -o disrealnew -lm -O2.
Here, the -lm instructs the compiler to include the math libraries and the -O2 (with a capital letter O) specifies the optimization level to be used by the compiler.
The 3-D cement hydration and microstructure development model is described in detail elsewhere [1, 2]. Once the initial 3-D microstructure and particle ID structures are read in, hydration is executed as a series of dissolution/diffusion/reaction cycles. In dissolution, any pixels of a soluble phase that are in contact with water-filled capillary pore space may dissolve and enter solution as one or more diffusing species. These diffusing species then undergo random walks within the pore space until a reaction occurs. After a specified number (typically 500) of diffusion steps have been taken, phase counts are tabulated, empty porosity created to account for the chemical shrinkage (if hydration is under sealed conditions), and another cycle of dissolution is executed. All diffusing species IDs and locations are stored in a dynamically allocated doubly linked list, so that the diffusing species may remain in solution from one dissolution cycle to the next. However, during the last diffusion step of the last cycle of the hydration, all diffusing species are converted into either the phase from which they dissolved or the appropriate hydration products.
In addition, after each dissolution cycle, the heat released by the reactions (as described in the next section) and the degree of hydration that has occurred are used to update the heat capacity and temperature of the system (if the hydration is being executed under adiabatic conditions). The heat capacity is a function of degree of hydration, and undergoes about a 10 % decrease during the course of hydration due to changes in the state of the water present in the cement paste [26]. Dividing the incremental heat release by the current heat capacity determines the incremental temperature rise of the system under adiabatic conditions. In this way, the adiabatic response of a concrete system may be predicted by estimating temperature as a function of equivalent real time, calculated based on the application of the principles of the maturity method [27].