There are many factors affecting the characteristics of cement-fly ash slurry in practical engineering. Thus, this paper studies the influence of multifactors on the fluid properties of cement-fly ash slurry based on water-cement ratio ( w / c ) (0.75, 1, 1.25, and 1.5), fly ash content (0%, 10%, 20%, 30%, 40%, and 50%) and temperature (20°C, 40°C, 60°C, and 80°C). The bleeding ratio, initial setting time, final setting time, and viscosity were analyzed under coupling conditions. It is found that the water-cement ratio ( w / c ) is the main factor that affects the rheological properties and bleeding rate of slurry. The temperature affects the stability of the slurry in terms that the bleeding ratio of the slurry decreases as the temperature increases. The addition of fly ash enhances the stability of the slurry under different temperature conditions.

It is studied the influence of triethanolamine (TEA), diethylenetriamine (DEA), Triisopropanolamine (TIPA), aminoethyl ethanolamine (AE), and polyvinyl alcohol ammonium phosphate (PAAP) at different dosages on the properties of fresh and hardened cement pastes and mortars prepared by Portland cement, including standard consistency water, setting time, the cement paste fluidity, and compressive and flexural strength. It is showed that the high polarity alcohol amine molecules exhibit strong chemical interactions with cement matrix, which are reflected in modified macroscopic properties of the cement system. All alcohol amine admixtures increased the standard consistency water and decreased cement paste fluidity of Portland cement. TEA significantly shortened the initial setting time and final setting time of Portland cement. On the other hand, TIPA, DEA, AE and PAAP extended the initial setting time of cement but shortened the cement final setting time. All alcohol amine admixtures except TIPA at 0.2 and 0.5 dosage increased the compressive and flexural strength of the Portland cement mortars at 3 days. Especially when the dosage of PAAP is 1, the compressive strength of the Portland cement mortars at 3 days is increased 10.5MPa. All alcohol amine admixtures except AE at 0.2 and 0.5 dosage increase the compressive and flexural strength of the Portland cement mortars at 28 days, Especially when the dosage of TIPA is 1, the compressive strength of the Portland cement mortars at 28 days is increased 8.8MPa.

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Hydration mechanism and performance of tri-cementitious material, which contains clinker, limestone powder and fly ash, are studied. It is showed that when mixed materials ratio increases from 20% to 40%, the water amount for standard consistency will increase remarkably, and when dosage of limestone powder is 50% in mixed material, the water amount for standard consistency will reach minimum, i.e. 26%; but when limestone powder ratio reaches 40%, the fluidity of slurry reaches maximum, and then it drops with increasing of limestone powder ratio. It is also found that increasing of dosages of mixed materials will decrease flexural strength and compressive strength, and increasing of ratio of limestone powders can result in decreasing of compressive strength at 28 days curing time, especially when ratio of mixed material is 20%. In order to explain the rules that above-mentioned, the particles size distribution is studied, and the hydration mechanism is analyzed.

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