41results about How to "Prolonged initial setting" patented technology

The invention belongs to the technical field of environment rock-soil engineering and discloses a high-efficiency curing method for a soft soil site with high moisture content. The high-efficiency curing method comprises an in situ chemical curing step and a preloading drainage step; the in situ chemical curing step comprises investigating sites, determining physical and chemical indexes such as depth, area, moisture content, organic matter content, liquid plastic limit and salt content of the soft soil site; blending a curing agent, determining the types, adding ratio, and initial and final setting time of the curing agent based on the physical and chemical indexes; blocking the site, and building partition walls for site blocking in the soft soil site; carrying out chemical curing construction, and uniformly mixing the blended curing agent with to-be-cured soft soil; carrying out preloading drainage construction according to three construction modes of vacuum preloading or surchargepreloading or vacuum surcharge preloading; unloading and repairing the site; after preloading time reaches 28 days, swabbing off drained water from the upper surface layer of curing blocks, unloadingand injecting cement slurry into a drain board for secondary repair and reinforcement by adopting a high-pressure grouting pump.

The invention discloses a modified cement slurry for rapidly repairing concrete, comprising following components in weight ratio: 30-70% of cement, 15-55% of aggregates, 12-15% of fly ash, 2.5-7.5% of latex powder, 0.25-5.5% of early strength admixture, and 0.25-1% of antifoaming agent. The modified cement slurry also comprises an expanding agent by weight of 0-2.5% of total weight and a thickening agent by weight of 0-2.5% of total weight. The modified cement slurry for rapidly repairing concrete can quicken the initial set of the cement slurry, promote water reducing rate of mortar, reduce unit weight of the newly-stirred mortar, and obviously promote flexural compression ratio, binding intensity and chloride ion penetration resistance of slurry, and the durability of concrete after rapidly repairing.

The invention discloses a preparation method of a delayed coagulation type ester polycarboxylate water reducing agent. The preparation method comprises the following steps: (1) preparing an esterification monomer; (2) performing a copolymerization reaction; and (3) performing a neutralization reaction. The preparation method utilizes a saccharide compound and crotonic acid to prepare the esterification monomer, and has the advantages of low costs and simple and convenient operation; the prepared saccharide esterification product participates in the next step of the copolymerization reaction, so that the main chain of the polycarboxylate water reducing agent has a polyhydroxy structure, and the prepared polycarboxylate water reducing agent has a better delayed coagulation effect, effectively prolongs the initial setting and final setting time of cement, and can reduce negative effects caused by using a retarder; and the polyhydroxy structure of the saccharide compound enables the polycarboxylatewater reducing agent to have better slump loss resistance, so that the pumping construction of concrete in summer is facilitated.

The invention discloses a hydration heat inhibition type concrete expanding agent and a preparation method thereof. The hydration heat inhibition type concrete expanding agent is prepared by compounding hydration heat inhibition type expanding clinker and gypsum, wherein the hydration heat inhibition type expanding clinker is prepared from the following raw materials in parts by weight: 50 to 70 parts of limestone, 5 to 15 parts of the gypsum, 2 to 5 parts of iron slag, 10 to 20 parts of bauxite and 0.1 to 3.0 parts of metal ions or metal oxide; the raw materials are fired at high temperatureby adopting an ion doping technology to prepare the hydration heat inhibition type concrete expanding agent. The preparation method provided by the invention is simple and feasible and the calcinationtemperature of expanding agent clinker is effectively reduced.

The invention provides a foam concrete slab production line, and belongs to the technical field of concrete production equipment. The foam concrete slab production line comprises storage equipment, conveying equipment, foaming equipment, stirring equipment, slurry storing, transporting and pouring equipment, foam concrete slab shaping platforms, grid paving equipment and press flattening equipment, the storage equipment is connected with the conveying equipment through the stirring equipment, the foaming equipment is used for making foams and connected with the stirring equipment through pipelines, the slurry storing, transporting and pouring equipment is used for movably pouring foam concrete and is positioned above the foam concrete slab shaping platforms which are used for holding the foam concrete, the grid paving equipment is used for paving grids on the foam concrete, the grid paving equipment and the press flattening equipment are connected above the foam concrete slab shaping platforms, and foam concrete dies are arranged on the foam concrete slab shaping platforms. The foam concrete slab production line has the advantage that through arrangement of working processes and mutual matching of the equipment, continuous production of large-earthwork-volume foam concrete slabs is realized.

The invention discloses cement clinker and a production method thereof. The method comprises the steps of preheating copper-lead tailings, sulfuric acid residues, limestone and sandstone by a step-by-step preheater, then decomposing by a decomposing furnace to obtain CaCO3, and firing into cement clinker, wherein the fired clinker comprises chemical components and mineral components, wherein the chemical components of the fired clinker include SiO2, Al2O3, Fe2O3, CaO, MgO, R2O and SO3, and the mineral components include tricalcium silicate (C3S), dicalcium silicate (C2S), tricalcium aluminum (C3A) and tetracalcium aluminoferrite (C4AF). The method is simple, can remarkably reduce coal consumption, reduces the standard consistency of the clinker to 24.0%, increases the strength to 61-62MPa, and can be applied to large-scale industry and production.

The invention relates to the technical field of cement for home decoration, and specifically discloses masonry cement for home decoration. The masonry cement for home decoration is prepared from the following raw materials in percentage by mass: 60-64% of clinker, 5-6.5% of desulfurized gypsum, 28-30% of limestone and 3-4% of slag. A production method for the masonry cement comprises the followingsteps: rolling clinker, desulfurized gypsum, limestone, slag and a grinding aid by adopting a roller press so as to obtain powder A; selecting the powder A by adopting a V-shaped powder selecting machine to obtain fine powder B and coarse powder C; feeding the coarse powder C into a ball mill for ball milling so as to obtain powder D; repeating the step 2 and the step 3 for the powder D, whereinthe fine powder B obtained in the step 2 is a finished masonry cement product. The masonry cement provided by the invention has multiple use functions such as easiness in mixing, easiness in smearing,proper initial setting time, high early strength, no bleeding, no layering, no bottom grabbing, strong cohesiveness, good durability, no brick cracking and no sand returning, and produces obvious social benefits.

The invention discloses bare concrete. The bare concrete is characterized by being prepared from, by weight, 5-10 parts of surface modified nano-boron fiber, 5-10 parts of kaolin, 10-15 parts of illite powder, 20-30 parts of gravel, 5-10 parts of vermiculite sand, 20-30 parts of silver sand, 40-50 parts of Portland cement, 1-5 parts of a compound additive and 20-30 parts of water. The compound additive comprises, by weight, 20-25 parts of a phosphate borate copolymer, 2-5 parts of zinc citrate, 1-3 parts of pyrophyllite powder, 1-3 parts of wollastonite powder, 2-4 parts of porous magnesium silicate, 0.5-1 part of a defoaming agent, 0.8-1.5 parts of polyaminopropyl biguanide, 0.5-2 parts of hydroxypropyl cyclodextrin, 1-3 parts of an activator and 80-100 parts of water. The invention further discloses a preparation method of the bare concrete. The bare concrete is high in compressive strength, good in corrosion resistance, impermeability and crack resistance and excellent in comprehensive performance, and production and application are safe and environmentally friendly.

The invention discloses a modified cement mortar for concrete repair and a preparation method thereof. The preparation method comprises the following steps: a) weighing and mixing predetermined amounts of cement, aggregate and fly ash; b) adding predetermined amounts of a butylbenzene emulsion, an antifoaming agent and an early strength agent into tap water and mixing the obtained solution with the mixture prepared in the step a); and c) controlling the fluidity of mortar to be in a range of 140 + / - 5 mm, separately measuring flow-table fluidity and unit weight of the newly-mixed mortar and carrying out casting molding for repairing when the determined flow-table fluidity and unit weight of the newly-mixed mortar are substantially identical to to-be-repaired concrete. According to the modified cement mortar for concrete repair and the preparation method thereof, initial set of the cement mortar can be accelerated, the water-reducing rate of the mortar can be increased, the unit weight of the newly-mixed mortar can be decreased, the ratio of bending-compressive strength of the mortar can be obviously enhanced, and rapidly repaired concrete has better durability.

The invention discloses a preparation method of a retarding type ester polycarboxylate water reducer, which comprises the following steps: (1) preparation of esterified monomers; (2) copolymerization reaction; (3) neutralization reaction. The preparation method of the present invention utilizes sugar compounds and crotonic acid to carry out esterification to prepare esterification monomers, which has the advantages of low cost and easy operation, and the prepared sugar esterification products participate in the next step of copolymerization reaction, making polycarboxylic acid The main chain of the superplasticizer has a polyhydroxyl structure, so that the prepared polycarboxylate superplasticizer has a good retarding effect, effectively prolonging the initial setting and final setting time of cement, and reducing the use of retarders. negative impact. Moreover, the polyhydroxy structure of sugar compounds makes the polycarboxylate superplasticizer have better slump retention performance, which is beneficial to the summer pumping construction of concrete.

The invention discloses a fair-faced concrete, which is characterized in that it is made of the following raw materials in parts by weight: 5-10 parts of surface-modified nano-boron fibers, 5-10 parts of kaolin, 10-15 parts of illite powder, and 20 parts of gravel ‑30 parts, 5‑10 parts of vermiculite sand, 20‑30 parts of fine sand, 40‑50 parts of Portland cement, 1‑5 parts of composite additives, 20‑30 parts of water. The composite additive includes the following components by weight: 20-25 parts of phosphate-based boric acid-based copolymer, 2-5 parts of zinc citrate, 1-3 parts of pyrophyllite powder, 1-3 parts of wollastonite powder, porous silicon Magnesium acid 2-4 parts, defoamer 0.5-1 part, polyaminopropyl biguanide 0.8-1.5 parts, hydroxypropyl cyclodextrin 0.5-2 parts, activator 1-3 parts, water 80-100 parts. The invention also discloses a preparation method of the fair-faced concrete. The fair-faced concrete disclosed by the invention has high compressive strength, good corrosion resistance, impermeability and crack resistance, excellent comprehensive performance, and safe and environment-friendly production and use.

The invention discloses a preparation method of a retarded ether type polycarboxylate water reducer, which comprises the following steps: (1) preparation of esterification monomer; (2) copolymerization reaction; (3) neutralization reaction. The preparation method of the present invention utilizes the esterification of saccharide compounds and crotonic acid to prepare esterified monomers, which has the advantages of low cost and simple operation, and the obtained saccharide esterification products participate in the next step of copolymerization reaction, so that polycarboxylic acid is The main chain of the superplasticizer has a polyhydroxy structure, so that the prepared polycarboxylate superplasticizer has a good retarding effect, effectively prolonging the initial setting and final setting time of cement, and reducing the use of retarders. negative impact. Moreover, the polyhydroxy structure of sugar compounds makes the polycarboxylate water reducer have better slump retention performance, which is beneficial to the summer pumping construction of concrete.

The invention discloses retarder applicable to sulphate aluminum cement. The retarder is composed of, by weight, 7-60 parts of carbamide, 3-11 parts of sodium lignin sulfonate, 2-7 parts of dinaphthyl methane disulfonic acid sodium, 2-5 parts of water reducing agent and 30-70 parts of vermiculite. By means of the retarder, the coagulation speed of the sulphate aluminum cement can be effectively reduced, the flowability of sulphate aluminum cement slurry can be remarkably improved, and the water demand in the sulphate aluminum cement mixing process can be reduced. The carbamide is added into the retarder, the coagulation time of the sulphate aluminum cement can be prolonged, nitrogen nutrient elements required by the plant growth can be further released slowly after the cement slurry is hardened, and the nitrogen nutrient elements are supplied to plants in porous plant-growing concrete for meeting the plant growth requirements.

The invention discloses an automatic heating and opening-closing method for a pre-curing kiln, and relates to the technical field of precuring kilns. The automatic heating and opening-closing method comprises a feeding stage for a concrete-loaded trolley into a pre-curing kiln, a maintaining stage for the concrete-loaded trolley maintaining in the pre-curing kiln and a warehouse-out stage for loading the concrete-loaded trolley out of the pre-curing kiln. According to the automatic heating and opening-closing method, the problem that the initial setting time of the concrete in winter is lengthen can be solved.

The invention belongs to the field of cement, and particularly relates to a retarded clinker and a preparation method thereof. The raw material of the slow-setting clinker of the present invention is composed of the following components in mass fractions: limestone, 81.0-93.0%; clay, 3.0-15.0%; non-ferrous metal ash, 1.0-5.0%; fluorite tailings, 1.5‑3.5%. Wherein, the content of calcium fluoride in the fluorite tailings is 15-30%. By adding a certain amount of fluorite tailings, the invention prolongs the initial setting and final setting time of the clinker, and realizes the production of the retarded clinker, thereby meeting the performance requirements of the retarded cement for special projects; The performance is still maintained, so it can ensure the quality of concrete while meeting the requirements for the retarding characteristics of cement; at the same time, the effective use of fluorite tailings broadens the utilization of fluorite tailings, and reduces the stacking and external discharge of waste-producing enterprises. Meet the needs of green environmental protection.

The invention discloses a method for automatically heating and opening and closing a pre-curing kiln, and relates to the technical field of pre-curing kilns. Including the storage stage for the trolley loaded with concrete to enter the pre-curing kiln, the maintenance stage for the trolley loaded with concrete to be maintained in the pre-curing kiln, and the out-of-warehouse stage for the trolley loaded with concrete to leave the pre-curing kiln . The invention can solve the problem that the initial setting time of concrete becomes longer in winter.