653results about How to "Reduce heat of hydration" patented technology

The invention discloses a construction method of a large-volume concrete bearing platform with one-time pouring in winter, comprising the following steps of: step 1, binding steel reinforcement cages; step 2, laying cooling water pipelines and temperature measuring elements; step 3, constructing formed templates, wherein the construction process comprises delimiting template lines and constructing formed brick dies; step 4, pouring concrete; and step 5, conserving and finishing surface: finishing surface in time when completing the pouring of the concrete, carrying out the surface finishing twice, carrying out the first surface finishing when pouring the concrete to the top, carrying out the second surface finishing when the concrete is initially congealed, and adopting a mode that external stores water for conserving when the concrete is initially congealed. The invention has the advantages of reasonable design, simple construction method step, convenient operation, short construction period, one-time pouring molding and strong maneuverability, the large-volume concrete bearing platform constructed for molding in winter has good quality, the poured concrete is not frozen, and the surface of the bearing platform can not have temperature cracks.

The invention relates to sea sand powder concrete. The sea sand powder concrete comprises, by weight, 450-750 parts of cement, 250-450 parts of active mineral admixture, 50-150 parts of inert admixture, 850-1400 parts of sea sand, 24-32 parts of high efficiency slushing agents, 145-220 parts of seawater, 2-4 parts of organic fiber and 78-250 parts of copper-bearing steel fiber with the thickness ranging from 0.08 mm to 0.35 mm. According to the sea sand powder concrete, a compact stacking structure principle is adopted, the interior of the concrete is almost seamless in communication channel through optimization of particle size gradation, and a channel of internal ion medium migration is further eliminated through secondary hydration of the active mineral additive, so that the powder concrete obtained by stirring the raw materials through the seawater and the sea sand is ultra-high performance concrete with high durability, corrosion resistance and high mechanic property.

The invention relates to concrete with ultra-large volume, high strength and low hydration heat. The concrete comprises the following components in parts by weight (cube dosage kg / m3): 200-260 parts of cement, 100-160 parts of mineral powder, 80-100 parts of fly ash, 740-800 parts of fine aggregate, 1010-1050 parts of coarse aggregate, 4.0-5.0 parts of additive and 155-165 parts of water. The concrete with ultra-large volume, high strength and low hydration heat can be used to effectively reduce the hydration heat, greatly reduce the cracking risk of the large-volume concrete from the source and increase the engineering quality.

Belonging to the field of cement production and also relating to the field of building materials, the invention provides a high early strength and high corrosion resistant Portland cement and a preparation method thereof. The high early strength and high corrosion resistant Portland cement is mainly applied to engineering projects in complex marine environments and the west harsh environments. The high early strength and high corrosion resistant Portland cement is characterized by containing, by weight percentage, 60%-90% of a high iron and low calcium cement clinker mineral component, 2%-10% of an auxiliary functional component, 5%-25% of an auxiliary cementitious component, and 3%-7% of industrial gypsum. The high iron and low calcium cement clinker mineral component is mainly prepared from high iron and low calcium Portland cement clinker and high iron and low calcium Q phase cement clinker in a mass ratio of 5-15:1. The cement not only has strong seawater erosion resistance and high early strength, but also has the characteristics of low shrinkage and low hydration heat.

The invention discloses a preparation method of a low-hydration-heat polycarboxylate water reducing agent. Unsaturated carboxylic acid or unsaturated carboxylic acid anhydride performs acidylation andesterification with alcohol amine and a compound A to simultaneously prepare unsaturated monomers with acidamide groups, unsaturated monomers with amino groups and unsaturated monomers with benzene rings and phosphate groups; then, co-polymerization is performed by excessive unsaturated carboxylic acid or unsaturated carboxylic acid anhydride, unsaturated sulphonate and polyether big monomers during acidylation and esterification; acylamide groups, amino groups, phosphate groups, carboxylate groups, sulphonate groups, polyether lateral chains and benzene rings are introduced into molecular structures, so that the product has a high initial water reducing rate. The molecular structures of the water reducing agent prepared by the preparation method comprise ester groups, phenyls and phosphate groups; the ester groups hydrolyze under the basic condition of the concrete; carboxyls with the water reducing function and hydroxy phenyl phosphate groups with the hydration heat reducing function are gradually released; the concrete hydration heat can be effectively reduced.

The invention discloses self-compacting powder concrete for ocean engineering as well as preparation method and an application. According to the concrete, coal ash and limestone flour are simultaneously added, the precipitation amount of calcium hydroxide is reduced, and the problem in the prior art that the concrete is poor in corrosion resistance can be solved; moreover, the concrete is doped with nano-scale calcium carbonate and silica fume, so that the self-compacting property of the concrete structure is improved. The comprehensive cost of the concrete is low, the material source is wide, and a great amount of industrial wastes can be doped; the seawater corrosion resistance is good, the self-compacting property is good, the expandability is high, hydration heat is low, the adjusting range of the working expandability is large, the early strength is high, the strength of the concrete is greater than 50Mpa at the first day and greater than 130Mpa at the 28th day, and the self-compacting powder concrete is suitable for different types of ocean engineering.

The phosphorous slag activating modifier is precipitant comprising one or several kinds of oxide, hydroxide, chloride and nitrate of Ca, Mg and Ba, and prepared through crushing. It is added into phosphorous slag to convert the slowly coagulating components in phosphorous slag into insoluble precipitate as stuffing component. The present invention makes it possible to utilize phosphorous slag to produce high-quality and low-cost cement and other building material.

The invention discloses low-dosage steel fiber modified powder concrete which comprises the following raw materials in parts by weight: 600-1000 parts of cement, 150-300 parts of active mineral admixture, 60-100 parts of inert admixture, 900-1300 parts of sand, 26-35 parts of a water reducing agent, 135-160 parts of water, 30-100 parts of extra-fine steel fibers and 7-12 parts of a corrosion inhibitor. According to the low-dosage steel fiber modified powder concrete, provided by the technical scheme of the invention, the extra-fine steel fibers with the diameters being smaller than 0.13 mm and the lengths being 6-12 mm are adopted for replacing common steel fibers, therefore on the one hand, the mechanical property of the concrete is improved, on the other hand, the additive amount of steel fibers in the concrete is further reduced, and the production cost of the low-dosage steel fiber modified powder concrete is reduced; besides, the low-dosage steel fiber modified powder concrete is relatively low in the wholesale cost, good in the fiber distribution uniformity, high in fracture resistance and shock resistance and is suitable for popularization and application in the constructional engineering industry.

The invention discloses a low-carbon high-performance tunnel shotcrete composite cementing material. The low-carbon high-performance tunnel shotcrete composite cementing material is used for shotcreting construction of roads, railway tunnels and urban underground engineering. The low-carbon high-performance tunnel shotcrete composite cementing material comprises 40% of cement clinker, 25% of slag powder, 15% of coal ash, 8% of silicon ash and 12% of a mixed material. A preparation method of the low-carbon high-performance tunnel shotcrete composite cementing material comprises the following steps of preparing the above materials of which performances satisfy requirements, respectively grinding cement clinker, a mineral mixture and the mixed material into powder having different specific surface areas, and homogenizing the powder according to a formula ratio by a homogenizer to obtain a target product. Compared with the common portland cement, the low-carbon high-performance tunnel shotcrete composite cementing material has the advantages that a mineral mixture amount is greatly improved; cementing material components are changed; and performances are greatly improved. A clinker doping ratio is reduced and thus carbon emission is reduced; environmental protection is realized; and resources and energy are saved.

The invention relates to steel slag concrete comprising the following components: cement, water, barite sand, stones, sintered pellets, a naphthalene high-efficiency water reducing agent, an expanding agent, and fly ash. The steel slag concrete has the advantages that the steel slag concrete is prepared by mixing the cement, water, the barite sand, the stones, the sintered pellets, the naphthalene high-efficiency water reducing agent, the expanding agent and the fly ash; the sintered pellets and the barite sand enable the density of the concrete to be effectively improved; with the use of the barite sand, the sintered pellets can be prevented from sinking, the separation resistance of the concrete is improved, and the amount of the cement is reduced; the fly ash effectively reduces the hydration heat of the concrete; with adulteration of the naphthalene high-efficiency water reducing agent, the work degree of the concrete is improved, the setting time of the concrete is delayed, the construction difficulty is effectively reduced, and the construction period is greatly shortened; and with reasonable utilization of the industrial waste residue sintered pellets, the energy is effectively saved, the environment is effectively protected, and the production cost is reduced.

The invention discloses a high efficiency cement composite grinding additive, comprising the following raw materials by weight percent: 10-25% of calcined gypsum, 10-30% of calcined aluminite, 20-40% of sodium metasilicate, 2-4% of triethanolamine, 0.5-2% of polyacrylate, 0.5-3% of dispersant and 20-30% of zeolite powder. The preparation method of the high efficiency cement composite grinding additive comprises the following steps: first selecting raw materials, then dripping liquid raw materials-triethanolamine and polyacrylate TH-1100 with a liquid pump in zeolite powder, then preparing reinforced grinding component with a dry powder mixer, finally adding the reinforced grinding component, calcined gypsum, calcined aluminite, sodium metasilicate and dispersant in a kneader to mix for 20-30min and obtaining the product. The product has prominent grinding aid, and can increase the hourly output of mills by 10-15%, reduce the consumption of electricity, and increase the cement 3-day compression strength and the cement 7-day compression strength by more than 20% and the cement 28-day compression strength by 10-15%.