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Ye'elimite (Ca4Al6SO16) is a main mineral in calcium sulfoaluminate cements. Aluminum hydroxide is one of the products formed by hydration of ye'elimite. To characterize this phase, various aluminum hydroxides were synthesized from their chemical constituents using sol‐gel processing and compared with the aluminum hydroxide formed during the hydration of ye'elimite. The nanostructure of aluminum hydroxide formed during the hydration of ye'elimite was investigated in detail using X‐ray diffraction, thermogravimetric analysis, scanning electron microscopy, inductively coupled plasma optical emission spectroscopy, and 27Al magic angle spinning nuclear magnetic resonance spectroscopy. No evidence was observed that indicated the existence of amorphous aluminum hydroxide in the hydration of ye'elimite. The pH values, thermogravimetric analysis, particle morphology, and Al‐O coordination indicated that the aluminum hydroxide from the hydration of ye'elimite had a crystal‐like structure. The X‐ray diffraction analysis, particle sizes, and ion activity product showed that the aluminum hydroxide from the hydration of ye'elimite had a microcrystalline structure.

The demulsification process of asphalt emulsion in fresh cement asphalt emulsion (CA) paste was investigated by measuring the viscosity and the particle size distribution of CA paste. The morphology evolution of asphalt droplets was also observed by optical microscope. Superplasticizer was used to adjust different demulsifying speed of asphalt emulsion in CA paste. Results indicate that the viscosity development of CA paste can reflect the demulsification process of asphalt emulsion in CA paste. The demulsification process of asphalt emulsion in CA paste has two main stages under the continual induction effect of cement hydration. Asphalt droplets in CA paste are firstly coalesced to big droplets, and then recover their adhesive force. In the first stage, the viscosity of CA paste increases little with the changing particle size distribution. However, the viscosity of CA paste increases sharply in the second stage.

Ye'elimite-containing cements are of growing research interest owing to their characteristic properties. Strontium (barium) (Sr(Ba))-bearing ye'elimite is synthesised by the substitution of Sr2+(Ba2+) ions for Ca2+ ions in ye'elimite. Here, Rietveld refinement for Sr(Ba)-ye'elimite is reported. The effect of strontic and baric substitutions on the crystal system of ye'elimite is analysed. Additionally, the crystalline phases and potential ACn (amorphous and non-quantified crystalline phase) contents, in clinkers containing Sr(Ba)-ye'elimite, are determined. As substitutions increase, the crystal system of Sr-bearing ye'elimite transforms from an orthorhombic system to a cubic system, but Ba-bearing ye'elimite remains cubic throughout the process. In the clinkers, the Sr-bearing ye'elimite reaches 97% (wt%) and the Ba-bearing ye'elimite is greater than 94% (wt%), with insignificant amounts of amorphous and non-quantified crystalline phase (ACn) contents. With a higher degree of substitutions, the lattice parameters of Sr(Ba)-bearing ye'elimite exhibit linear growth trends.