Abstract: The invention discloses an ultra-high-toughness multifunctional self-assembly C-S-H gel material and preparation method thereof. The ultra-high-toughness multifunctional self-assembly C-S-H gel material includes several stacked core-shell structure layers, wherein the core-shell structural layer is composed of several core-shell structure particles; the core-shell structure particles are composed of calcium silicate hydrate nanoparticles as the core and poly(acrylamide-co-acrylic acid) as the shell. The obtained ultra-high-toughness multifunctional self-assembly C-S-H gel material has high toughness, good tensile performance and temperature sensitive effect.

Abstract: The invention discloses an in-situ high-strength gradient carbonized material and the preparation method thereof. The in-situ high-strength gradient carbonized material includes a core structure composed of partially calcined calcium carbonate and a shell structure; the shell structure comprises calcium hydroxide and calcium carbonate and covers the outer layer of partially calcined limestone. The invention utilizes an in-situ carbonization reaction to recycle a large amount of low-grade limestone stored or discarded in industry, providing a new technological route for solid waste disposal and resource utilization; this method not only has a green and low-carbon process but also can be widely applied in carbon dioxide capture/collection technology, as well as the preparation of new low-carbon gel materials and concrete.

Abstract: The invention discloses high-strength glass-ceramic-based lightweight aggregates and the preparation method thereof. The mass ratio of raw material components is 50-70 parts of engineering muck, 20-40 parts of glass, 3-7 parts of calcium carbonate, 3-7 parts of magnesium oxide, and 2-10 parts of a nucleating agent; the nucleating agent is at least one of calcium fluoride, titanium dioxide, and chromium oxide. After crushing, mixing, and granulating, spherical particles with a particle size of 10-12 mm are formed; and then the product can be obtained after drying, sintering, and cooling. The obtained lightweight aggregate from the invention has a diopside matrix which provides high strength and a low water absorption rate at low densities. Moreover, waste glass and engineering muck could be utilized with high value.

Abstract: The invention discloses high-strength glass-ceramic-based lightweight aggregates and the preparation method thereof. The mass ratio of raw material components is 50-70 parts of engineering muck, 20-40 parts of glass, 3-7 parts of calcium carbonate, 3-7 parts of magnesium oxide, and 2-10 parts of a nucleating agent; the nucleating agent is at least one of calcium fluoride, titanium dioxide, and chromium oxide. After crushing, mixing, and granulating, spherical particles with a particle size of 10-12 mm are formed; and then the product can be obtained after drying, sintering, and cooling. The obtained lightweight aggregate from the invention has a diopside matrix which provides high strength and a low water absorption rate at low densities. Moreover, waste glass and engineering muck could be utilized with high value.

Abstract: Disclosed is a magnesium-based cementitious material, preparation method and application thereof. The magnesium-based cementitious material, comprising magnesite, sandstone, and water, wherein: the magnesite is provided with CaO, SiO2, Al2O3, Fe2 O3, and MgO, a mass percentage of the CaO is less than 5%, a mass percentage of SiO2 is less than 5%, a mass percentage of Al2 O3 is less than 5%, a mass percentage of Fe2 O3 is less than 7%, a mass percentage of MgO is between 37% and 50%; the sandstone is provided with SiO2, CaO, Al2 O3, and Fe2O3, a mass percentage of SiO2 is greater than 70%. The beneficial effects of this disclosure are: the cementitious material does not contain MgCl2, which avoids the reduction of the strength of the cementitious material due to the dissolution of MgCl2 in water; the magnesium-based cementitious material of this disclosure is immiscible with water and has strong water resistance.

Abstract: Disclosed is a CO2 solidified fiber cement board and its preparation method. The matrix composition of the fiber cement board prepared in this disclosure is calcium carbonate, which has high compactness, and the crystal form of calcium carbonate is adjusted by adding shell powder to improve the toughness of the matrix, so that the fiber cement board has excellent mechanics and durability performance. In addition, the preparation process does not require high temperature maintenance, and has the characteristics of normal temperature preparation, which creates conditions for the introduction of organic synthetic fibers, so that the organic synthetic fibers can further improve the brittleness of cement fiberboard. While reducing energy consumption, the preparation process can also effectively solve the problem that excessive pressure is easily generated in the fiberboard under high temperature conditions in the existing high-temperature and high-pressure curing process.

Abstract: Disclosed is a magnesium-based cementitious material, preparation method and application thereof. The magnesium-based cementitious material, comprising magnesite, sandstone, and water, wherein: the magnesite is provided with CaO, SiO2, Al2O3, Fe2O3, and MgO, a mass percentage of the CaO is less than 5%, a mass percentage of SiO2 is less than 5%, a mass percentage of Al2O3 is less than 5%, a mass percentage of Fe2O3 is less than 7%, a mass percentage of MgO is between 37% and 50%; the sandstone is provided with SiO2, CaO, Al2O3, and Fe2O3, a mass percentage of SiO2 is greater than 70%. The beneficial effects of this disclosure are: the cementitious material does not contain MgCl2, which avoids the reduction of the strength of the cementitious material due to the dissolution of MgCl2 in water; the magnesium-based cementitious material of this disclosure is immiscible with water and has strong water resistance.

Abstract: Disclosed is a CO2 solidified fiber cement board and its preparation method. The matrix composition of the fiber cement board prepared in this disclosure is calcium carbonate, which has high compactness, and the crystal form of calcium carbonate is adjusted by adding shell powder to improve the toughness of the matrix, so that the fiber cement board has excellent mechanics and durability performance. In addition, the preparation process does not require high temperature maintenance, and has the characteristics of normal temperature preparation, which creates conditions for the introduction of organic synthetic fibers, so that the organic synthetic fibers can further improve the brittleness of cement fiberboard. While reducing energy consumption, the preparation process can also effectively solve the problem that excessive pressure is easily generated in the fiberboard under high temperature conditions in the existing high-temperature and high-pressure curing process.

Abstract: The present disclosure discloses a method and an article for improving the strength of carbonated calcium hydroxide compacts. The method includes the following steps: calcium hydroxide-rich materials, ordinary portland cement, magnesium hydroxide, pottery sand and water are mixed according to the mass ratio of 100:15-20:15-20:40-80:10-20, then the mixture was compressed, carbonated and naturally cured to obtain the carbonated compacts. The present disclosure utilizes cement hydration and magnesium hydroxide carbonation to consume the water produced by calcium hydroxide carbonation, the C-S-H gelation effect produced by cement hydration, the cementation effect of magnesium hydroxide carbonation products, the volume expansion effect of magnesium hydroxide carbonation and the gas transmission channel and internal curing effect of pottery sand further improve the carbonation degree, product gelation, thus greatly improving the strength of carbonated calcium hydroxide compacts.

Abstract: The invention discloses a calcium-alumino-silicate-hydrate nano-seeds suspension and preparation method thereof. The preparation method of calcium-alumino-silicate-hydrate nano-seeds suspension includes the following steps: dropwise adding the aqueous solution of calcium source, the aqueous solution of silicon source and the aqueous solution of aluminum source to the solution of polycarboxylate superplasticizer, and adjusting the pH value to 10.0˜13.5, and continuously stirring to obtain the calcium-alumino-silicate-hydrate nano-seeds suspension. The beneficial effect in the present invention is: the calcium-alumino-silicate-hydrate nano-seeds has small particle size, good dispersion stability, and it can effectively improve the early hydration and mechanical performance of cement-based materials, and has good application prospects; the preparation process is simple, without washing, drying, ultrasonic dispersion and other subsequent processes, suitable for large-scale production.

Abstract: The invention discloses an artificial nacre material with layered structure and preparation method thereof. The preparation method includes the following steps: uniformly mixing a carbonated cementitious material and water at a water-solid ratio of 0.3 to 1.2 to obtain a carbonated cementitious material suspension; treating the carbonated cementitious material suspension by a freeze-casting process to obtain a carbonated cementitious material coagulation with layered structure; treating the carbonated cementitious material coagulation with the layered structure by a freeze-drying process to obtain a carbonated cementitious material with layered structure; treating the carbonated cementitious material with layered structure by a carbonization process to obtain an artificial nacre material with layered structure.

Abstract: The invention discloses an artificial nacre material with layered structure and preparation method thereof. The preparation method includes the following steps: uniformly mixing a carbonated cementitious material and water at a water-solid ratio of 0.3 to 1.2 to obtain a carbonated cementitious material suspension; treating the carbonated cementitious material suspension by a freeze-casting process to obtain a carbonated cementitious material coagulation with layered structure; treating the carbonated cementitious material coagulation with the layered structure by a freeze-drying process to obtain a carbonated cementitious material with layered structure; treating the carbonated cementitious material with layered structure by a carbonization process to obtain an artificial nacre material with layered structure.

Abstract: The invention discloses a calcium-alumino-silicate-hydrate nano-seeds suspension and preparation method thereof. The preparation method of calcium-alumino-silicate-hydrate nano-seeds suspension includes the following steps: dropwise adding the aqueous solution of calcium source, the aqueous solution of silicon source and the aqueous solution of aluminum source to the solution of polycarboxylate superplasticizer, and adjusting the pH value to 10.0˜13.5, and continuously stirring to obtain the calcium-alumino-silicate-hydrate nano-seeds suspension. The beneficial effect in the present invention is: the calcium-alumino-silicate-hydrate nano-seeds has small particle size, good dispersion stability, and it can effectively improve the early hydration and mechanical performance of cement-based materials, and has good application prospects; the preparation process is simple, without washing, drying, ultrasonic dispersion and other subsequent processes, suitable for large-scale production.