73results about How to "Low early strength" patented technology

The invention belongs to the field of building materials and concretely relates to modified phosphogypsum and a preparation method thereof. The modified phosphogypsum is characterized by being formed by mixing, wetly grinding and then aging phosphogypsum, general-purpose silicate cement and water, wherein the accounted dry-basis mass percentages of the phosphogypsum and the general-purpose silicate cement are as follows: 95-99 percent of phosphogypsum and 1-5 percent of general-purpose silicate cement, and the sum of the accounted dry-basis mass percentages of the phosphogypsum and the general-purpose silicate cement is 100 percent; and the addition quantity of the water is 50-70 percent of the total mass of the phosphogypsum and the general-purpose silicate cement, and the addition quantity of the water includes the quantity of free water in the phosphogypsum. The method has the advantages of simple process, no need of high-temperature curing, less admixture dosage and low cost, and the coagulating time of phosphogypsum-based cement concrete can be shortened by the modified phosphogypsum which is prepared by the method.

The invention provides a low-viscosity high-strength environmentally friendly double-component glue solution and a preparation method thereof and relates to a sodium silicate-polyurethane double-component adhesive which can be used in the industries of construction and building materials and the like. The low-viscosity high-strength environmentally friendly double-component glue solution is prepared from sodium silicate and/or potassium silicate and polyisocyanate and their derivatives and further at least contains a coupling agent and/or coupling agent and polyol ester and/or alcohol ether suitable for being matched with the sodium silicate, the polyurethane component is prepared from polyisocyanate and an end-NCO prepolymer of polyether polyol and/or polyether glycol of the polyisocyanate, the mixture contains NCO 10-26%, and the matching ratio of the two components is in positive correlation with the specific gravity of the sodium silicate and is in negative correlation with the modulus of the sodium silicate within a certain range and is 1 to 0.7-2.5. The silane coupling agent is firstly added during preparation, and then the polyol ester and/or the alcohol ether is added after uniform stirring. The low-viscosity high-strength environmentally friendly double-component glue solution has low viscosity, excellent wettability and adhesion and good bonding strength and waterproof and weather-resisting properties, is adjustable in adaptation period, is naturally cured, makes the surface tough, bright and clean and is low-carbon, environmentally friendly, flame-retardant, rustproof, simple in process and low in cost.

The invention relates to an active mineral waste residue powder production system and a technological process of the system. In the mineral waste residue powder production process, the speed of a conveyed material is adjusted, the air quantity is controlled, and a powder concentrator is optimized and reformed, so that the fineness and the specific surface area of the superfine slag powder are greatly improved; a preparation method of the active mineral waste residue powder is simple; empty grinding and full grinding are prevented, so that running and labor intensity can be lightened, the maintenance cost is reduced, the work environment is improved, the whole grinding process is automatically controlled, and the whole grinding process is optimized; the active mineral waste residue powder production system has the advantages of being reasonable in structure and convenient to operate.

The invention discloses a cement clinker and belongs to the technical field of cement clinker production. The clinker is prepared from the following raw materials in percentage by mass: 30 to 60 percent of calcareous materials, 0 to 25 percent of siliceous materials, 10 to 40 percent of aluminum materials, 0 to 10 percent of ferrous materials and 5 to 20 percent of gypsum materials; a mineral composition of the clinker is prepared from 10 to 40 percent of C4AS, 25 to 40 percent of C2S and 10 to 30 percent of C4AF. According to the clinker disclosed by the invention, the iron content of the cement clinker is low, and the seawater erosion resisting ability of the clinker is improved; the cement clinker is especially suitable for marine engineering.

The invention provides a fly ash surface modifying material and a using method thereof. The fly ash surface modifying material is prepared with a surfactant commonly used as a concrete admixture and an air entraining agent. The fly ash surface modifying material is prepared by dissolving the surfactant and the air entraining agent in water to prepare a modifying material water solution, forming a modifying material atomized agent through an atomizer, utilizing compressed air to feed the modifying material atomized agent into a fly ash bin from the bottom of the fly ash bin to be fully mixed with fly ash so as to enable carbon particles in the fly ash to pre-adsorb the surface modifying material. Microporous surfaces of the carbon particles are blocked, so that adsorption effect, on a water reducing agent, of the fly ash surface modifying material when the fly ash is used for concrete is reduced, and fluidity of the concrete is improved; the modifying material adhered on the surfaces of other spherical particles of the fly ash can play a role in lubricating, so that fluidity of fly ash concrete is further improved; the surface modifying material is extremely low in consumption, and a gas arch breaking device originally in the fly ash bin can be utilized to complete surface modification of the fly ash, so that the fly ash surface modifying material and the using method are low in cost.

The invention belongs to the field of buildings, in particular to a cement clinker, hydraulic engineering cement for an impervious wall of a dam and application thereof. The invention provides a cement clinker with optimized mixture ratio, wherein the cement clinker is prepared into cement which is applied to the hydraulic engineering cement for the impervious wall of the dam and has the characteristics of low strength at early stage and high strength at late stage. The cement clink comprises the following minerals in percentage by weight: 25-40 percent of C3S, 42-63 percent of C2S, 1-3.5 percent of C3A, 11-16 percent of C4AF and 0-2 percent of inevitable impurities. The concrete prepared from the cement clinker and the cement as raw materials has the characteristics of low hydration heat, low strength at early stage, high strength at late stage, non-hanging strength and the like, is suitable for hydraulic engineering of the impervious wall of the dam and can replace special hydraulic engineering cement for the concrete prepared from the traditional moderate-heat cement, low-heat cement or general purpose portland cement.

The present invention is aimed at providing a technological process for producing pipe pile by adopting fine-ground metallurgical slag and fine-ground high-silicon sand reblending method. When said invented technique is used to produce pipe pile, the fine-ground metallurgical slag and fine-ground high-silicon sand can be mixed according to a certain proportion, and said mixture can be substitutedfor 30%-60% of high-grade Portland cement or general Portlant cement with above 42.5-level to produce pipe ile. Said method not only can utilize furnace slag, but also reduce addition quantity of cement, and raise early-strength and after-strength of pipe pile concrete.

The invention discloses a complete set of tunnel mechanical equipment, which specifically refers to an excavation trolley (or an excavation gantry), a drainage and steel bar binding trolley, a liningtrolley, a spray maintenance trolley, a ditch cable trough trolley, an inverted arch self-propelled hydraulic trestle and a wet spray manipulator, referred to as five trolleys, one trestle and one wetspray machine. A construction organization method matched with the complete set of mechanical equipment comprises the following construction organization steps: S1, hole excavation; S2, initial support; S3, inverted arch lining; S4, arched wall lining; S5, ditch cable troughs and the complete set of mechanical equipment. The construction organization method is reasonable, effectively improves tunnel management effect, improves construction operation environment, ensures construction safety and quality, improves construction progress and is worthy of promotion.

The invention provides a low-heat Portland cement with high early strength and a preparation method and application thereof. The cement comprises, by mass, 80-95 parts of low-heat Portland cement clinker, 0-15 parts of mineral slag, 0-15 parts of silica fume, 0.03-0.05 part of graphene oxide and 5 parts of gypsum; the low-heat Portland cement clinker comprises, by mass, 30-45 parts of C3S, 37-47 parts of C2S, 1-5 parts of C3A and 10-15 parts C4AF. Through the addition of the mineral slag and the silica fume as admixtures of the low-heat cement and through the addition of graphene oxide as a modifier, the intrusion of erosive media can be effectively suppressed and the occurrence of initial erosion damage can be delayed, so that the early strength performance of the low-heat cement is improved while low hydration heat and high crack resistance are maintained; the low-heat Portland cement has the advantages of good crack resistance, good resistance to chloride ion and sulfate erosion andthe like, and therefore is more suitable for practical use.

The invention discloses a method for improving the hydration activity of waste glass powder. The method comprises the following steps: carrying out cleaning, airing, preliminary crushing and jaw crushing on waste glass having different colors and kinds, collected from salvage stations, and carrying out ball milling by a ball mill for 60-120 min to obtain the waste glass powder; carrying out dry screening, wet screening and a settlement process on the waste glass powder to obtain waste glass powder with the particle size range of 10-75 [mu]m and the particle specific surface area being greater than 400 m<2>/kg; and adding cement and a composite exciter to the waste glass powder, carrying out mixing milling treatment for 30 min, adding water, pouring the obtained mixture into a cement neat paste stirrer, and stirring the mixture for 2-3 min to obtain a composite gelling material. The composite gelling material prepared in the invention is a waste glass recycled product, waste glass has a high utilization rate, wide sources and easiness in obtaining, and the composite gelling material has the advantages of quickness in setting, quickness in hardening, high early stage strength, and great increase of the later strength.

The invention discloses a method for preparing a low-clinker and high-phosphorus-slag cement composite cementitious material. The method comprises the following steps: weighing 15-25% by mass of clinker, 40% by mass of phosphorus slag, 5-15% by mass of metakaolin, and 30% by mass of compound admixture consisting of steel slag, fly ash, limestone and gypsum according to a mass ratio of 5 to 10 to 10 to 5; and mechanically mixing, adding water according to a water cement ratio of 0.5 after uniformly mixing, and stirring for 2min to obtain the low-clinker and high-phosphorus-slag cement composite cementitious material. By adding the metakaolin, the problems that the low-clinker and high-phosphorus-slag cement composite cementitious material has lower early strength and longer setting time are solved, and the optimum added quantity of the metakaolin is obtained and is between 5% and 15%. The preparation method provided by the invention is simple, the clinker quantity can be reduced, other industrial wastes such as phosphorus slag can be more fully utilized, the environmental pollution is reduced and the energy saving and emission reduction are realized.

The invention discloses a grinding aid for improving the adaptability of a high-alumina clinker cement admixture, and solves the technical problems that a grinding aid in the prior art causes lowadaptability of high-alumina clinker cement to the admixture and reduces the early strength of the high-alumina clinker cement. The grinding aid comprises: 3%-20% of dimer glycerol; 10%-27% of monoethanol diisopropanolamine; 2%-7% of hydroxyethylidene diphosphonic acid; 0.1%-0.25% of polyacrylamide; and the balance of water. Compared with a traditional grinding aid, the grinding aid for improving the adaptability of the high-aluminum clinker cement admixture has higher admixture adaptability, the fluidity of neat paste is improved by 20 mm or above, the slump of C30 and C25 concrete is improved by 15 mm or above, and the expansion degree is improved by 15 mm or above; and the formula of the grinding aid is optimized to improve the 28-day strength of the high-alumina clinker cement concrete.

The invention discloses a concrete water-reducing agent and the application of the concrete water-reducing agent. The concrete water-reducing agent comprises the components by weight ratio: 58-80 parts of polycarboxylate high-performance water-reducing agent and 20-42 parts of compound containing hydroxyl and carboxyl. According to the concrete water-reducing agent, the advantages of the polycarboxylate high-performance water-reducing agent can be developed and the adaptability of the polycarboxylate high-performance water-reducing agent can be improved, in addition, the dosage is reduced, resources are saved, energy consumption is reduced and the comprehensive application cost of the polycarboxylate high-performance water-reducing agent can be lowered.

The invention discloses a supersulfide phosphogypsum phosphorus slag cement concrete product and a preparation method thereof. The supersulfide phosphogypsum phosphorus slag cement concrete product comprises the following raw material components: phosphogypsum, phosphorus slag, silicate cement, sand, stones, a water reducing agent and water. Through early-stage wet grinding of the phosphogypsum and the phosphorus slag, the strength of the material in each stage is greatly improved, the production process is simple, the cost is low, a large amount of industrial solid waste can be used, and environmental protection is facilitated.

The invention relates to the field of precast concrete components, in particular to full-automatic steam curing equipment and method for a precast concrete component. The full-automatic steam curing equipment comprises a steam curing cover, an automatic steam curing temperature controller and an electric heating boiler, wherein four steam curing stages are arranged in the automatic steam curing temperature controller and include the static stopping stage, the temperature rising stage, the constant temperature stage and the temperature lowering stage. During steam curing, parameters in the four steam curing stages are set respectively. By means of the full-automatic steam curing equipment and method for the precast concrete component, the steam-cured precast concrete component can smoothly reach the strength required by form removal, corner cracks are obviously reduced, the quality of the small precast component is improved, remarkable technical achievements and economic benefits are obtained, and the equipment and method are well accepted by owners.

The invention provides a downward parallel middle-deep hole sublevel fill stoping mining method for a steep and medium-thick hard-to-mine ore body, and belongs to the technical field of mining. The ore body is divided into a plurality of sublevels according to the middle sublevel, stope rooms and stope pillars are divided in the ore body direction, the middle sublevel is divided in the inclined direction of the ore body, sublevel rock drilling roadways are arranged along veins, artificial false roofs and false bottoms are constructed in the sublevel rock drilling roadways in advance, and middle-deep hole stoping ore blocks are adopted from top to bottom. After the stope rooms are mined, the stope rooms are filled with filling materials. After the stope pillars are mined, the stope pillarsare filled with full tailings and/or barren rock powder. The content of particles with the particle size being less than or equal to 30[mu]m in the full tailings for the filling materials accounts for75-77%; the content of the particles with the particle size being less than or equal to 35[mu]m in slag accounts for 86-88%; and an activator is prepared from glauberite and green vitriol with a weight ratio of 1 to (0.5-0.7). According to the downward parallel middle-deep hole sublevel fill stoping mining method, safe, efficient and low-cost mining of the ore body can be realized, continuous mining in an area can be realized, and the sublevel fill stoping mining method is mainly suitable for a gold mine with an inclination of 50-90 degrees and a horizontal thickness of 4-10 m.

The invention discloses a concrete of strength grade C55 for a profile steel reinforced concrete structure. The concrete contains the ingredients: cement, fine aggregates, coarse aggregates, water, an efficient water reducing agent, an antifoamer, silica fume, fly ash and a composite excitant, wherein the ratio (kg/m<3>) of the cement to the fine aggregates to the coarse aggregates to the water to the efficient water reducing agent to the antifoamer to the silica fume to the fly ash to the composite excitant is 330: 713: 1186: 160: 6: 1: 30: 80: 2.5. A preparation method of the concrete comprises the steps of firstly, uniformly mixing the polycarboxylic acid efficient water reducing agent and the composite excitant with the weighed water so as to obtain a mixture, sequentially adding the fine aggregates and 1/3 the total weight of the mixture into a stirrer according to a weight ratio, carrying out stirring, adding the coarse aggregates and 1/3 the total weight of the mixture into the stirrer, carrying out stirring, adding the cement, the silica fume and the fly ash into the stirrer, carrying out stirring, adding the antifoamer and the remaining mixture into the stirrer, carrying out stirring, and carrying out discharging. The concrete can be used for remarkably improving the bonding property between profile steel and the concrete in a state of nature, and respective mechanical properties and mutual cooperated working performance of two kinds of materials, i.e., the steel and the concrete are effectively exerted, so that the bearing capacity and use performance of structural elements are substantially improved, and the durability of structures is improved.

The invention discloses a method for applying electrolytic-aluminium waste cathode carbon blocks in combined production of sulfuric acid and cement from phosphogypsum. The method comprises the following steps: smashing the phosphogypsum, carrying out drying and dehydrating so as to obtain hemihydrate gypsum, crushing the electrolytic-aluminium waste cathode carbon blocks into a powder material, mixing the powder material with the hemihydrate gypsum, clay and bauxite, carrying out on-line drying, after completion of drying, carrying out integrated grinding so as to obtain a phosphogypsum cementraw material, preheating the raw material, delivering the preheated raw material into a hollow rotary kiln for decomposition and calcination, subjecting generated SO2-containing gas to gas-solid separation, carrying out dedusting and purifying, then delivering obtained gas into a sulfuric acid system so as to prepare a finished sulfuric acid product, subjecting the raw material to high-temperature calcination so as to obtain a cement clinker, blending the cement clinker with certain amounts of coal cinder and fly ash, and carrying out grinding with a ball mill so as to obtain the cement. Themethod provided by the invention realizes reutilization of the electrolytic-aluminium waste cathode carbon blocks and the phosphogypsum, eliminates the influence of wastes on the environment, saves the cost of occupied land, seepage prevention treatment and the like for waste residue storage at the same time, and has significant economic and environmental benefits.

The invention discloses concrete with a strength grade C30 for a steel reinforced concrete composite structure. The mixture ratio of cement to fine aggregate to coarse aggregate to water to an efficient slushing agent to an antifoaming agent to silica fume to coal ash to a composite catalyst (kg/m<3>) is 270:742:1124:140:4:1:20:60:2. A preparation method of the concrete comprises the steps that the polycarboxylate-type efficient slushing agent and the composite catalyst are firstly stirred into the weighed water evenly to obtain a mixture, 1/3 of the total quantity of the fine aggregate and the mixture is sequentially added to a stirrer according to the weight ratio, stirring is carried out, 1/3 of the total quantity of the coarse aggregate and the mixture is added, and stirring is carried out; the cement, the silica fume and the coal ash are added, and stirring is carried out; the antifoaming agent and the residual mixture are added, and stirring and discharging are carried out. By means of the concrete, the bonding performance between profile steel and the concrete can be remarkably improved in a natural state, the respective mechanical properties and the cooperative working property of the steel and the concrete can be effectively achieved, and therefore the bearing capacity and use performance of a structural member are greatly improved, and the durability of the structure is improved.

The invention relates to the technical field of concrete admixtures, in particular to a composite antifreezing agent of concrete for rush-repair engineering. The composite antifreezing agent is prepared from, by weight, 10-20 parts of diatomite, 3-10 parts of tributyl phosphate, 2-8 parts of sodium hexametaphosphate, 3-6 parts of sodium sulfate, 2-10 parts of oxidized graphene, 5-12 parts of dicyclohexyl carbodiimide, 1-5 parts of alkyl organic amine, 0.2-1 part of triterpenoid saponis, 2-5 parts of initiator, 6-12 parts of acrylamide, 0.2-1 part of surfactant, 2-8 parts of calcium lignosulfonate, 3-8 parts of aminosulfonate, 8-10 parts of sodium gluconate, 0.2-2 parts of silane coupling agent, 0.1-1 part of formic acid and 20-30 parts of alcohol. The composite antifreezing agent can accelerate setting speed of the concrete at minus 20 DEG C and improve strength and durability of the concrete.

The invention discloses a construction method of a conjoined mortar piling wall which is used for retaining and protecting for foundation excavation in the field of buildings. The construction method comprises the following steps of: sinking a steel sleeve to a designed elevation at a first piling position by using high-frequency hydraulic vibratory piling hammering machine along a central line of a conjoined piling wall; taking out soil in the steel sleeve; after a formed pore is qualified, putting sand soil taken out from the steel sleeve mixed with water, cement or lime into a stirrer for uniformly stirring; pouring the stirred mortar into the steel sleeve; pulling out the steel sleeve in a high frequency way to form a first mortar piling; then sinking a pipe to the designed elevation at a second piling position which is engaged with the first piling position; and repeating piling-forming construction steps to form the conjoined mortar piling wall. The construction method is applicable to constructions of water seepage prevention and earth-supporting-pile wall structure under any geological conditions, except rock strata; the close-grained mortar body pilings are formed in the frequency vibration way while pulling the steel sleeve by a piling machine; and by utilizing local materials, not only spoil and freight of construction materials can be reduced, but also construction cost can be reduced under the premise of ensuring the water seepage prevention effect.

The invention discloses a preparation method of an autoclaved aerated concrete block. The preparation method comprises the following steps: S1, preparing an additive A from aluminum powder paste, sodium sulfate and sodium abietate; and preparing fly ash, bagasse, juncus roemerianus powder, lime powder, gypsum powder and the additive A into ball billets, and curing to obtain lightweight aggregate; s2,preparing fly ash, ceramic tile waste, glass waste, quicklime and gypsum powder into a mixture; s3, preparing sodium hydroxide, rosin powder, triethanolamine and sodium silicate into an additive B; and S4, preparing a brick blank from the lightweight aggregate, the mixture, cement and the additive B, and maintaining the brick blank to obtain the autoclaved aerated concrete block. The invention further discloses the autoclaved aerated concrete block which is prepared by the preparation method of the autoclaved aerated concrete block. According to the autoclaved aerated concrete block, the construction waste, the household waste and the industrial waste are reasonably utilized, waste is turned into wealth, resource waste and environmental pollution are reduced, and the autoclaved aerated concrete block which is high in compressive strength and breaking strength and light in weight is prepared.