5results about How to "Improve volume stability" patented technology

The application belongs to the technical field of refractory materials, and relates to a multi-metal composite magnesium-alumina spinel-containing refractory material and a preparation method thereof. The material of the magnesium-alumina spinel-containing refractory material is one of SiC-MgAl2O4, Al2O3-MgAl2O4 and MgO-MgAl2O4; the main body of components of the magnesium-alumina spinel-containing refractory material is granular SiC, Al2O3 and MgO as aggregate and a mixture of fine powder and micro powder composed of MgAl2O4 as matrix, and the components contain metal Al and Al-Mg alloy; the magnesium-alumina spinel-containing refractory material is prepared through hot air drying at 150-200 DEG C for 8-24 hours, and high-temperature sintering is not needed; the magnesium-alumina spinel-containing refractory material is a composite refractory material with alpha-SiC or corundum or periclase as main crystal phase and magnesium-alumina spinel as secondary crystal phase. The application realizes that the formed green body only needs to be treated at low temperature not higher than 200 DEG C, and can meet good mechanical properties, structural stability and corrosion resistance in a use temperature range of 25-1600 DEG C, and the built-in hot work thermal reserve can realize high mechanical strength and volume stability from normal temperature to the highest use environment through the waste heat in the oven heating process.

This application discloses a micro-expansion low-heat silicate cement-based concrete material, its preparation method, and its application, belonging to the field of concrete engineering technology. Each cubic meter of micro-expansion low-heat silicate cement-based concrete material comprises 78-92 kg of water, 82-161 kg of micro-expansion low-heat silicate cement, 28-105 kg of fly ash, 476-608 kg of sand, and 1286-1696 kg of aggregate. The dosage of naphthalene-based water-reducing agent is 0.4 wt%-0.6 wt%, and the dosage of air-entraining agent is 0.014 wt%-0.018 wt%. The air content of the concrete material in the mixed state is 4%-5%, and the slump is 35-50 mm. Through the synergistic proportioning of water, micro-expansion low-heat silicate cement, fly ash, sand, and aggregate, the low heat of hydration and micro-expansion characteristics of micro-expansion low-heat silicate cement are fully utilized.

This application relates to the field of building materials technology and discloses a low-cost micro-expansion ultra-high performance concrete and its preparation method. The raw materials of the concrete include water, cement, silica fume, limestone powder, fine aggregate, coarse aggregate, polycarboxylate superplasticizer, CaO-calcium sulfoaluminate-based composite expansion agent, and sodium polyacrylate-based internal curing agent. The fine aggregate is river sand, and the coarse aggregate is basalt crushed stone. During preparation, the powders are first mixed dry, then an aqueous solution of the superplasticizer is added and stirred into a uniform slurry. The aggregate is then added, stirred, and finally molded and cured. This invention utilizes the internal curing agent to desorb moisture when the internal humidity of the concrete matrix decreases, providing moisture compensation for the later hydration of the composite expansion agent, causing the dense matrix to undergo micro-expansion deformation and convert it into self-stress. This solution effectively compensates for the volume shrinkage caused by the low water-cement ratio, reducing the risk of cracking. Simultaneously, the use of conventional sand and gravel instead of pure quartz sand significantly reduces the cost of large-scale preparation.

This application discloses a steel pipe jacking core filling material and its preparation method. The raw materials of the steel pipe jacking core filling material in this application include gel material, coarse aggregate, fine aggregate, wetting and dispersing agent, and water. The weight of the wetting and dispersing agent is 1.0-1.5% of the total mass of the gel material. The wetting and dispersing agent is compounded from maleic anhydride copolymer and organic bisacrylic surfactant. The cementing material includes cement, mineral powder, and fly ash. The molecular structure of the maleic anhydride copolymer is comb-shaped. The molecular weight of the main chain of the maleic anhydride copolymer is 5000-100000 g / mol, and the molecular weight of the side chain of the maleic anhydride copolymer is 100-500 g / mol. The molecular structure of the organic bisacrylic surfactant is comb-shaped. The molecular weight of the main chain of the organic bisacrylic surfactant is 5000-100000 g / mol, and the molecular weight of the side chain of the organic bisacrylic surfactant is 2000-5000 g / mol. The filler material in this application has better fluidity and density properties, and better volume stability, which can meet the dual requirements of mechanical properties and durability of lifting filler materials.

The application relates to the technical field of cement materials, and particularly discloses a high ore fused stone ferrite aluminate cement material and a preparation method thereof. The cement material is prepared by jointly grinding and treating high belite ferrite aluminate cement clinker and a modifier. The modifier is composed of succinyl phosphonate, a quaternary ammonium salt and an aluminum source. The molecular formula of the succinyl phosphonate is HOOC-CH2-CH2-CO(PO3H2). The modifier composed of succinyl phosphonate, a quaternary ammonium salt and an aluminum source is used to perform mechanochemical coupling modification on the belite ferrite aluminate cement clinker, multi-level interface interaction occurs under the induction of mechanical force, directional poisoning and growth inhibition of calcium aluminate crystal nuclei are realized, the early strength of the cement is maintained, and the volume stability of the cement material is significantly improved.