75results about How to "Small loss over time" patented technology

The invention discloses a super early strength accelerator for portland cement concrete. The super early strength accelerator is prepared from the following constituents in percent by weight: 20-50% of an early strength constituent, 10-40% of quick setting constituent, and 20-45% of a water reducing constituent, wherein the early strength constituent is obtained by compounding at least two of hydramine, an organic salt and an inorganic salt; the quick setting constituent is one of sodium aluminate, aluminum sulfate and sodium silicate; the water reducing constituent is one of a polycarboxylate type high performance water reducer, a high-performance naphthalene-based superplasticizer, and a high-performance aliphatic superplasticizer. The super early strength accelerator disclosed by the invention is free of chlorine and alkali; the 16 h compressive strength of the portland cement concrete prepared by using the super early strength accelerator in a low temperature environment in winter is up to 20 MPa above, so that the portland cement concrete can meet the requirement on quick road repair, and achieves the excellent construction performance.

The invention discloses a modified steel slag composite admixture and a preparation method thereof. The modified steel slag composite admixture comprises 55-75wt% of micro mineral slag powder, 20-40wt% of micro steel slag powder, and 1-5wt% of sintering desulphurization slag. Concrete prepared by mixing the modified steel slag composite admixture of the invention with cement has the following characteristics: the seven day active index is greater than 75%, the twenty-eight day active index is greater than 100%, the specific surface area is equal to or greater than 400m<2>/kg, the sulfur trioxide content is equal to or less than 4.0%, the chloride ion content is equal to or less than 0.06%, the ignition loss amount is equal to or less than 3.0%, and the autoclaving stability is qualified. The modified steel slag composite admixture which allows a low early strength disadvantage of steel slag composite admixtures to be overcome, working performances of concrete to be effectively improved, the strength and the endurance of concrete to be improved, and energy consumption required by slag grinding to be effectively reduced and is in favor of the low carbon economy realization, is a resource use type concrete admixture.

The invention belongs to the field of building materials and particularly discloses a high-fluidity sleeve grouting slurry for rebar connection and a preparation method thereof. The grouting slurry isprepared from the following materials in parts by weight: 390-410 parts of cement, 90-110 parts of admixture, 460-500 parts of sand, 0.05-0.07 part of a water-retaining agent, 1.4-1.6 parts of a de-foaming agent, 6-8 parts of a compound water reducer, 40-50 parts of compound retarder, 35-40 parts of a compound expanding agent, 7-10 parts of a compound early strength agent and 135-145 parts of water. The preparation method for the grouting slurry comprises the steps of proportionally weighting the raw materials and uniformly stirring in a certain stirring manner. The sleeve grouting slurry forrebar connection prepared according to the invention is high in fluidity and can solve the problems of more insufficient initial fluidity or lower surplus initial fluidity and poorer fluidity holdingability than those of standard slurry of the present sleeve grouting slurry for rebar connection in practical engineering application.

High-performance cement, concrete and its production are disclosed. The cement consists of industrial fag end, activator, functional regulator and performance regulator, and Bosi specific surface is 300-550m2/kg. Its advantages include excellent fluidity and endurance, less loss and hydrated heat energy, better density and strength.

The invention relates to a preparation method of a naphthalene-series water reducing agent. The method comprises the following steps: (1) methylnaphthalene and phenol are separately sulfonated, such that a sulfonated methylnaphthalene material and a p-hydroxybenzenesulfonic acid material are obtained; (2) the sulfonated methylnaphthalene material is subjected to a hydrolysis reaction; un-reacted methylnaphthalene or homologs thereof are removed through zeotropy; the rest of the sulfonated methylnaphthalene material enters a reaction in the step (3); (3) the sulfonated methylnaphthalene material obtained in the step (2) and the p-hydroxybenzenesulfonic acid material obtained in the step (1) are subjected to a condensation reaction with formaldehyde acidified with concentrated sulfuric acid, such that a condensed material is obtained; and (4) alkali liquid is added into the condensed material obtained in the step (3), such that a neutralization reaction is carried out, until the pH value is 7.5-9; and the naphthalene-series water reducing agent is obtained when the reaction is finished. The naphthalene-series water reducing agent provided by the invention has the excellent performances of good adaptability to cement, good concrete workability, high plasticity-maintaining performance, low concrete gradual loss, high water reducing rate, and the like. The preparation method has the advantages of simple process and easy-to-control reaction conditions. With the method, naphthalene-series water reducing agent production cost can be reduced.

The present invention provides the recipe of chlorine ion penetration resisting reinforcer for concrete in harbor engineering. The chlorine ion penetration resisting reinforcer consists of superfine silica powder 15-20 wt%, washed and calcined kaolin 20-25 wt%, high grade fly ash 20-25 wt%, ground blast furnace slag 20-25 wt%, nanometer fiber 5-10 wt%, superplasticizer 6 wt%, slump keeping agent 0.09 wt%, air entraining agent 0.09 wt%, and organic active excitant 0.12 wt%. The chlorine ion penetration resisting reinforcer has inorganic components as main functional materials dispersed homogeneously in concrete cementing material, and can improve the micro structure and hydration product composition inside concrete, raise compactness, adsorb and fix chlorine ion and lower the penetration of chlorine ion in hardened concrete, so as to improve the chlorine ion penetration resisting capacity of hardened concrete.

The invention belongs to the technical field of concrete and proposes a mud-resistant polycarboxylate superplasticizer. The mud-resistant polycarboxylate superplasticizer is prepared from components in parts by weight as follows: 350-450 parts of isoamyl alcohol polyoxyethylene ether, 40-70 parts of acrylic acid, 18-36 parts of hydroxyethyl acrylate, 6-16 parts of an initiator, 1-5 parts of a chain transfer agent, 4-15 parts of a cationic monomer and 10-50 parts of a coagulation adjusting component. The preparation method of the mud-resistant polycarboxylate superplasticizer comprises steps asfollows: material preparation, preparation of materials A and B, dissolution, droplet adding of the materials A and B, thermal insulation ageing, neutralization and the like. The mud-resistant polycarboxylate superplasticizer is applied to preparation of concrete. With the adoption of the technical scheme, the problem that application of the polycarboxylate superplasticizer is affected due to massive adsorption by mud in the prior art is solved.

The invention discloses high-performance lithium slag pump concrete. The proportion of mixture of the concrete is cement:water:mineral powder:fly ash:lithium slag:sand:gravel:synergist: additive being (340-520):(165-200):(0-50):(0-50):(40-150):(700-850):(1,000-1,100):(2-3.5):(7-12) according to the component unit of kg/m<3>. By means of selection of the raw materials and design of proportioning, the high-performance lithium slag concrete which is good in working performance, mechanical performance and durability and can be used for pumping is obtained.

The invention discloses a slag powder-doped composition for preparing white facing as-cast finish concrete. The composition is characterized by consisting of the following components in parts by weight: 180-260 parts of cement, 85-110 parts of water, 330-390 parts of sand, 500-580 parts of stone, 2.0-4.0 parts of additive, 1 part of titanium dioxide and 20-60 parts of slag powder. In the composition disclosed by the invention, the proportion of the components is more scientific and reasonable, and the working performance meets the requirements on concrete pumping and pouring; and moreover, the bleeding and separation are avoided, the shrinkage is low, and the formed concrete is dense and has strong texture. With the formula, the large-flow regime white as-cast finish concrete has the advantages of good fluidity, good workability, good water-retaining property, low slump loss, strong pumpability and the like in concrete construction; and the strength of the formed concrete can be guaranteed, the surface gloss is good, and the chromatic aberration meets the requirement on the quality of the facing as-cast finish concrete.

The invention relates to the technical field of concrete preparation, and in particular, relates to a concrete glue reducing agent and a preparation method thereof. The glue reducing agent is composedof the preparation raw materials in parts by weight: 20-30 parts of substituted organic amine and 40-60 parts of water, wherein substituent groups of the substituted organic amine are selected from one or more of ester groups, sulfonic acid groups, carboxylic acid groups and hydroxyl groups. The invention provides the glue reducing agent. The glue reducing agent can be used in concrete, can obviously reduce the cement consumption, avoids the reduction of the concrete strength and slump, effectively reduces the time loss of the concrete, improves the harmony of the concrete, can act together with a water reducing agent and the like, saves the cost while ensuring the physical properties of the concrete, and conforms to JC/T2469-2018.

The invention discloses a recycled concrete, which is characterized in that the recycled concrete is prepared from the following components by weight: 60~95 parts of water, 40~64 parts of cement, 38~62 parts of ore powder, 22~34 parts of fly ash, 280~350 parts of natural sand, 210~260 parts of recycled coarse aggregate, 70~120 parts of recycled fine aggregate, 6~8 parts of silicon powder, and 1~2parts of modified polyacrylic acid high-efficiency water reducing agent. In conclusion, the recycled concrete has the advantages of improving the compressive property of concrete and improving the rheological property, mechanical property, volume stability and durability of concrete.

The invention discloses an ultrahigh-property cement-based material with low shrinkage and high toughness and a preparation method thereof. The ultrahigh-property cement-based material with low shrinkage and high toughness is prepared from the main components in parts by weight: 590-680 parts of ordinary Portland cement, 280-305 parts of fine sinking beads, 90-115 parts of silica fume, 1050-2000 parts of river sand, 29-67 parts of expanding agent, 180-240 parts of steel fiber, 18-23 parts of water reducing agent and 155-190 parts of water. The ultrahigh-property cement-based material and the preparation method disclosed by the invention have the beneficial effects that the preparation process is simple, and the ultrahigh-property cement-based material with excellent properties in all the aspects of fluidity, strength and the like can be prepared by adopting a conventional cement mortar planetary stirring machine; in addition, on the basis of meeting the basic specification requirementsof all admixtures and by common action of the raw materials, the use amount of cementitious materials can be obviously saved. The obtained ultrahigh-property cement-based material has the advantagesof low use amount of the cementitious materials, simple forming process, excellent working property, low comprehensive cost and less early shrinkage, so that the application prospect is wide.

The invention discloses a low slump loss modified naphthalene series water-reducing agent which is characterized in that: the water-reducing agent is formed by mixing 87-97 percent of naphthalene series water-reducing agents and 3-13 percent of oxidation-etherification starch by weight percentage; by adopting the invention, the water-reducing agent contains a great amount of hydroxyl, cement hydration can be prevented, so as to lead the cement hydration products to be uniform and improve the slump-blocking performance of the water-reducing agent; the water-reducing agent in the invention is applied to the cement, the reducing amount of the mobility is more than 6 percent after two hours, 28d intensity is improved by more than 12 percent, therefore, the invention not only can ensure the water-reducing effect and reduce the slump economic loss, but also can effectively improve the cement and concrete intensity.

The invention relates to the technical field of concrete preparation, in particular to concrete containing natural zeolite powder. The concrete is prepared from the following components in parts by mass: 54-81 parts of lightweight sand, 30-56 parts of lightweight aggregates, 38-60 parts of cement, 9-14 parts of zeolite powder, 0.5-2 parts of a water reducer, and 18-28 parts of water. A preparationmethod comprises the following steps: S1, adding lightweight sand, lightweight aggregates, cement and zeolite powder into a stirrer, starting the stirrer to obtain a material mixture; and S2, addingwater and water reducer into the material mixture, continuously stirring for a certain period of time to obtain the concrete containing the natural zeolite powder. The concrete provided by the invention can effectively improve water-retaining property of the concrete, improves viscosity of the concrete, reduces gradual loss of the concrete, and meanwhile guarantees good pumpability performance ofthe concrete, boosts production efficiency, and also effectively relieves dead load, and guarantees structure safety.

The invention provides a preparation method of a modified naphthalene water reducer, which comprises the following steps: adding naphthalene and naphthol to a reaction kettle in a ratio of 1:1, heating and adding concentrated sulfuric acid, and then performing sulfonation reaction; cooling the materials and adding polyethylene glycol 600 for further reaction; then adding cold water for hydrolysis,cooling and controlling the temperature between 100-110 DEG C, adding naphthylacetic acid and uniformly mixing, adding formaldehyde for condensation; preserving heat for 2.5h, neutralizing with alkaline, so as to obtain a modified naphthalene water reducer liquid product, and performing spray drying, thus obtaining a powdery product. According to the invention, by adding naphthol and naphthylacetic acid, hydroxyl and carboxyl are introduced to the water reducer; after sulfonation reaction, a monomer which has a polyoxyethylene ether long chain and can participate in condensation reaction canbe produced by further acid catalysis action; a water reducer obtained by copolycondensation has sulfonyl, hydroxyl, carboxyl and polyoxyethylene ether long chain in the molecular chain. Sulfonyl, hydroxyl and carboxyl have a synergistic water reducing effect.

The invention discloses a high-early-strength, freeze-proofing and high-performance polycarboxylate water reducer. The water reducer is prepared from the following components by weight in a preferred range: 10-14 percent of polycarboxylate water reducer, 1-3 percent of sodium gluconate,0.5-1.5 percent of calcium nitrate, 1-3 percent of polyethyleneglycol, 3-5 percent of polyethyleneglycol, 3-5 percent of cupric sulfate, 0.5-1.0 percent of air-entraining agent and the balance of water.

The invention relates to a polycarboxylic acid high-performance water reducer. The poly polycarboxylic acid high-performance water reducer is prepared from the following raw materials in parts by weight: 25-35 parts of acrylic acid, 10-20 parts of mercaptoacetic acid, 30-50 parts of isopentenol polyoxyethylene ether, 1-10 parts of hydrogen peroxide, 1-10 parts of vitamin C, 1-5 parts of white sugar, 0.5-2 parts of sodium dodecyl sulphate and 25-60 parts of water. The polycarboxylic acid high-performance water reducer has excellent performance, high water-reducing rate, low mixing amount, small slump gradual loss, good adaptability and good gel material adaptability, a production process is easy in operation, heating is not needed, purified water is not needed, energy consumption is low, and the polycarboxylic acid high-performance water reducer is green.

The invention provides a solid flaky polycarboxylate slump retaining agent prepared by surfactant-free emulsion polymerization and a method. The solid flaky polycarboxylate slump retaining agent is prepared from the following components in parts by weight: 18-27 parts of a surfactant-free emulsion ester-based hydrophobic monomer, 0.48-0.72 parts of an initiator a, 9-18 parts of a surfactant-free hydrophilic small monomer, 0.41-0.69 parts of a chain transfer agent a, 765-810 parts of a polyether macromonomer, 32-68 parts of unsaturated dicarboxylic acid, 12-28 parts of an unsaturated sulfonic small monomer, 50-74 parts of alkyl acrylate, 2.3-3.8 parts of a chain transfer agent b, 3.2-5.9 parts of an initiator b, 2.6-4.6 parts of an initiator c, 3.2-4.7 parts of a chain transfer agent c, and7.7-11.5 parts of a pH regulator. The method comprises the following operation steps: (1) preparing a surfactant-free polymer; (2) preparing solutions A, B and C; (3) dropwise adding the solutions A,B and C; and (4) preparing the solid flaky polycarboxylate slump retaining agent. The slump retaining agent can effectively slow down cement hydration, effectively keep concrete slump for a long time, slow down the time-dependent loss of the concrete slump and keep the fluidity and workability of concrete, and the properties in all aspects are more stable.

The invention discloses a synchronous shielding grouting material composite admixture which comprises the following raw materials in percentage by mass: 10-20% of a coagulant, 10-20% of a retarder, 40-50% of an efficient water reducer, 10-20% of a tackifier, 1-5% of a defoaming agent and 1-5% of a plasticity expander. The admixture has the effects that in a high-pressure water-enriched stratum environment, on premise that equipment and pipelines are not changed, the curing time can be adjusted, the working performance loss is small within the curing time, and good water dispersibility resistance, efficient filling and rapid curing can be achieved.