A simple relationship between the compressive strength and porosity of hydrated portland cement

Previous work has shown that, for a series of experimental autoclaved aerated concretes with porosities ranging from 0.48 to 0.78, compressive strength is linearly related to the solid/pore volume ratio determined by helium pycnometry. In the work described here, this type of relationship has been applied to experimental data from hydrated Portland cement specimens, prepared using initial water/cement ratios of 0.35 to 0.50 and curing times of 2 to 28 days, with porosities ranging from 0.26 to 0.45. The relationship was found to provide a good fit using data obtained both by varying the water/cement ratio at constant curing times and by varying the curing time at constant water/cement ratios.