Papers by Keyword: Moisture Loss

Abstract: The effects of wood fiber and polypropylene fiber on the mechanical performance, drying shrinkage and moisture loss of sulphoaluminate cement (SAC) mortar were studied. The experimental results show that wood fiber and polypropylene fiber can both improve the flexural strength of the mortar and reduce drying shrinkage ratio and moisture loss at different ages. Polypropylene fiber can also improve the late compressive strength of the mortar. Adding 0.3% mass fraction of wood fiber, the drying shrinkage ratio and moisture loss of the motar reach minimum values. The drying shrinkage ratio reduces to 0.029% at 28d. Moisture loss reduces to 0.4%. Adding 0.5% mass fraction of polypropylene fiber, the drying shrinkage ratio and moisture loss of the motar also reach minimum values. The drying shrinkage ratio reduces to 0.03% at 28d and moisture loss reduces to 0.39%.

Abstract: In this project, a process was developed to cure concrete masonry blocks using CO2. It was found that the strength of concrete mixtures for block manufacture after CO2 curing was close to that after conventional steam curing. A dry pre-conditioning before CO2 curing was very critical to achieve high degree of CO2 curing. The specimen pre-conditioned in the moist environment hydrates more than those pre-conditioned in the dry environment during the pre-conditioning period. However, much less CaCO3 formed in the former that that in the latter after the CO2 curing. Thus, the CO2 curing is mainly contributed by the reactions between CO2 gas and cement clink minerals.