4results about How to "Appropriate setting time" patented technology

This invention discloses an early-strength, high-stability road grouting repair material and its preparation, belonging to the field of solid waste utilization and road grouting reinforcement technology. The raw materials of the early-strength, high-stability road grouting repair material of this invention include multi-source solid waste aggregates and a water-reducing agent; the multi-source solid waste aggregates, by mass percentage, include: 6.6 wt% fly ash, 5-15 wt% rapid-hardening sulfoaluminate cement, 64-74 wt% mineral powder, 13.4 wt% desulfurized gypsum, and 1% carbide slag. This invention constructs a quaternary solid waste system of fly ash-desulfurized gypsum-mineral powder-carbide slag, synergistically forming a slurry composite system with rapid-hardening sulfoaluminate cement and a water-reducing agent, and precisely controls the concentration of raw materials. During hydration, this system can generate supporting crystals, which not only provide high early-stage stone strength for the road grouting material, but also, due to its good stability, ensure high stone strength stability in the later stages.

The invention discloses a composite activator, a titanium extraction tailing-based cementing material using the composite activator and a preparation method of the cementing material, and belongs to the technical field of constructional engineering materials. The composite exciting agent comprises the following components in percentage by mass: 19%-27% of calcium sulphoaluminate cement, 17%-38% of aluminum sulfate, 2%-16% of calcium formate, 0%-17% of sodium silicate and 16%-42% of copperas. The preparation method comprises the following steps: doping a composite activator into a standard gelling system consisting of titanium extraction tailings, titanium gypsum, cement and lime according to a proportion of 1-5%, and enabling the median particle diameter D50 of mixed powder to be less than 15 microns through a co-grinding process. In order to solve the problems of slow development of early strength and generally low performance of the titanium extraction tailing-based cementing material, the synergistic excitation effect among the components in the composite exciting agent is utilized to promote rapid formation of ettringite and acceleration of hydration reaction, so that efficient utilization of solid waste in the titanium extraction industry is realized, and the utilization rate of the titanium extraction tailing-based cementing material is improved. The technical bottleneck of low early strength of the existing titanium extraction tailing-based cementing material is effectively solved, and the titanium extraction tailing-based cementing material is suitable for occasions with higher requirements on early strength, such as mine filling, roadbed engineering and the like.

The application belongs to the technical field of brick and stone cultural relics protection, and particularly discloses a metakaolin-based calcium phosphate chemical bonding mortar, a preparation method and application thereof. The mortar is composed of the following raw materials in percentage by mass: 11.0-14.0% of high-activity coarse metakaolin, 3.0-5.0% of high-activity superfine metakaolin, 13.0-17.0% of calcium dihydrogen phosphate-hydrate powder, 52.0-56.0% of mullite sand, and the balance of mixing water. Compared with the prior art, the repair material can have compatibility, safety and certain weather resistance with the brick and stone cultural relics, the molar ratio of phosphorus and aluminum of the reactant is controlled, the particle size grading of the metakaolin is adjusted, the proportion of the product crystal and amorphous structure is regulated, and then the metakaolin-based calcium phosphate chemical bonding material with a strength gradient is prepared. The setting time of the prepared material is appropriate, the shrinkage rate is low, and there is no soluble salt, so the material has high applicability for the repair and reinforcement of the brick and stone cultural relics.

The application provides a quick-setting magnesium oxychloride bone cement as well as a preparation method and application thereof. The raw material composition of the quick-setting magnesium oxychloride bone cement comprises a solid phase and a liquid phase; the solid phase comprises magnesium oxide, magnesium chloride, zinc chloride and strontium hydrogen phosphate; and the liquid phase is water. The mass ratio of zinc chloride to magnesium chloride is (1-2):(9-8); the mass of strontium hydrogen phosphate is 3-5 wt.% of the total weight of magnesium oxide, magnesium chloride and zinc chloride. The ratio of the total mass of zinc chloride and magnesium chloride to the mass of water is 1:11-17; and the ratio of the total mass of zinc chloride and magnesium chloride to the mass of magnesium oxide is 1:6-9. The composite magnesium oxychloride bone cement prepared by the application has a suitable setting time, is convenient for clinical operation, has a high compressive strength, meets the strength requirement of dense bone, and can be used for bone repair of load-bearing parts.