169results about How to "Reduce shrinkage cracks" patented technology

The invention discloses an environment-friendly colorful tile joint mixture. The environment-friendly colorful tile joint mixture is characterized by comprising the following components in percentage by weight: 35%-40% of white cement, 40.73%-47.75% of waste porcelain powder, 0-15% of quartz powder, 0-10% of titanium dioxide, 1%-1.5% of re-dispersible emulsion powder, 0.1% of water repellent, 0.15% of water-retaining agent, 0.4% of lignin fiber, 0.1%-0.25% of water reducing agent and 0-2% of pigment. The invention further discloses a preparation method of the environment-friendly colorful tile joint mixture. The consumption of quartz sand and heavy calcium powder is reduced by using the waste porcelain powder as the joint mixture filler; the early strength of the joint mixture is improved by virtue of early strength function of the white cement, so that the construction process requirements are satisfied. The waste porcelain powder is sintered at a high temperature, so that the physical and chemical performances are stable, the volume is stable, and the expansion-shrinkage coefficient is close to that of the tile; the material with the same expansion-shrinkage coefficient is used as the filler, so that the possibility that the tile joint mixture generates cracks can be further reduced.

The invention belongs to the technical field of building materials and particularly relates to low-shrinkage, low-viscosity and ultrahigh strength concrete. Based on a single formula proportional dosage, the low-shrinkage, low-viscosity and ultrahigh strength concrete comprises the following components by weight: 250-300kg of cement, 120-180kg of microspheres, 90-120kg of mineral powder, 820-860kg of machine-made sand, 950-1000kg of gravels, 7-11kg of a water reducer and 115-125kg of water. The components are mixed with stirring for 1.5-2 minutes to obtain a concrete mixture. The concrete provided by the invention is less in binding material use, the total shrinkage percentage is less than (0.03-0.04per mill), the emptying time of an inverted slump cone is 5-10 seconds, the viscosity of mortar in same proportion is 20-28 Mp.s, the 28d compressive strength is 110-130MPa, and the 56d compressive strength is 120-135MPa. The concrete has the characteristics of being low in bonding material use, short in stirring time, excellent in working performance and low in comprehensive cost, and can be produced on a large scale and has a broad application prospect.

The invention discloses a fluidized bed combustion ash and high titanium slag compounded stable pavement base material. The fluidized bed combustion ash and high titanium slag compounded stable pavement base material is formed by mixing 30-90wt% of fluidized bed combustion ash with 10-70wt% of high titanium slag. The fluidized bed combustion ash, the high titanium slag and water are stirred and mixed, and the obtained mixture is molded and maintained to make a fluidized bed combustion ash and high titanium slag compounded stable pavement base. The compounded stable pavement base material completely utilizes difficult-treatment and high-discharge-amount industrial wastes comprising the fluidized bed combustion ash and the high titanium slag, contains no lime or fly ash, and has better performances than traditional lime-fly ash stable pavement base material; and the compounded stable pavement base material has the advantages of low cost, no consumption of natural resources, simple and easy preparation method, suitableness for being used in areas short of traditional road engineering materials, substantial economic benefit, wide market prospect and strong practicality.

The invention relates to high-intensity low-crack cement-stabilized graded macadam and a preparation method thereof, belonging to the field of highway engineering design. The mineral aggregate gradation of the high-intensity low-crack cement-stabilized graded macadam is 5-6 grade, wherein the 4.75mm pass ratio is 35-40%, and the crushing value of large-particle macadam is lower than 22%. By adopting the above technical scheme, the invention has the following beneficial effects: (1) the 7d unconfined compressive strength of the cement-stabilized graded macadam is increased to 6-8MPa; and (2) the coefficient of shrinkage of the cement-stabilized graded macadam is decreased to 0.008-0.013. Therefore, the technical advantages of high intensity and low shrinkage crack of mixture are achieved; the macadam of the invention is applied to building the road surface with long service life, in this way, the bearing property of the road surface is improved, and the service life of the road surfaceis prolonged.

The invention discloses anti-permeating and anti-cracking concrete, which relates to the technical field of concrete. The technical scheme of the anti-permeating and anti-cracking concrete mainly comprises the following raw materials in parts by weight: 177-192 parts of water, 202-262 parts of portland cement, 734-830 parts of sand, 1,002-1,012 parts of stones, 51-65 parts of coal ash, 60-77 partsof mineral powder and 3.79-4.61 parts of an additive, wherein the additive comprises modified polypropylene fibers, a water-proofing agent and a water-reducing agent at a weight ratio of 3.2-4.7: 1.3-2.5: 1.7-2.3; the water-proofing agent comprises a triethanolamine water-proofing agent, an air-entraining water-reducing agent and a micro-expansion water-proofing agent at a weight ratio of 1.1-1.5: 1.3-1.7: 0.7-1.3. According to the anti-permeating and anti-cracking concrete, the problems that the concrete is cracked easily after hardening and is relatively poor in anti-permeating performanceare solved. By adding the modified polypropylene fibers and the water-proofing agent, the concrete can be prevented from being cracked when in hardening, so that the anti-permeating performance of theconcrete is improved.

The invention discloses foam concrete containing recycled inorganic lightweight aggregate. The foam concrete is prepared from 20-60 parts of cement, 20-60 parts of slag, 0-50 parts of sand, 0.5-3 parts of a water reducer, 0.1-3 parts of fibers, 25-60 parts of water, foam with the addition amount accounting for 1-80% of the total volume of the foam concrete and the recycled inorganic lightweight aggregate with the addition amount accounting for 1-80% of the total volume of the foam concrete, wherein the recycled inorganic lightweight aggregate is obtained by smashing, screening and grading one or more inorganic heat insulation building materials including but not limited to aerated concrete, foam concrete, foamed ceramic and foamed glass. The invention further discloses a preparation method of the foam concrete. The foam concrete containing the recycled inorganic lightweight aggregate has the advantages of being high in strength, small in shrink, free of formwork collapse, good in fluidity, homogeneous, low in cost and the like and is especially suitable for cast-in-situ lightweight walls, roofs, lightweight cement product elements and the like.

The full name of the invention is recycled concrete made of discarded fiber and a preparation method thereof. The technology supplies a novel concrete material formed by using the discarded fiber and discarded concrete as aggregates. After the discarded fiber and the discarded concrete are disposed according to a regulation, the discarded fiber and the discarded concrete with cement, sands, macadam and water are mixed evenly according to a certain ratio, and then a novel construction material with high intensity is formed. By means of the recycled concrete, the discarded concrete can be largely consumed, recycling rate of the discarded fiber is improved, and environmental pollution is reduced. Improvement of use ratio of discarded textile fiber, recycling of construction waste and management of solid waste are of great significance. Therefore, the current situation of resource shortage of the country can be effectively improved, resources can be conserved, resource utilization rate can be improved, and better development of the novel construction material of the country can be achieved.

The invention discloses high-performance corrosion-resistant dry-mixed waterproof mortar. The high-performance corrosion-resistant dry-mixed waterproof mortar is prepared from the following raw materials in parts by weight: 60-70 parts of cement, 35-45 parts of mineral powder, 10-30 parts of coal ash, 300-500 parts of regenerated fine aggregates and 5-10 parts of a compounded additive, wherein the compounded additive is prepared from the following raw materials in parts by weight: 40-60 parts of coal ash, 5-7 parts of a water repellent, 40-50 parts of an expanding agent, 2-5 parts of an air-entraining and water-reducing agent, 2-4 parts of anti-crack short fiber and 2-10 parts of a water-retaining thickening agent. By virtue of a dry-mixing form, the high-performance corrosion-resistant dry-mixed waterproof mortar is convenient to use, and the sulfate corrosion can be effectively prevented.

The invention discloses a seamless construction method of a multi-layer super large-area reinforced concrete ground. According to the method, no expansion joint or late poured band is arranged in the ground concrete construction; the ground is divided into a plurality of pieces by using construction joints according to a certain size; the adjacent pieces are poured at intervals; and the ground is connected and poured to an integer after the first-poured concrete is subjected to large shrinkage deformation. The seamless construction method of the multi-layer super large-area reinforced concrete ground, disclosed by the invention, has the advantages of greatly shortening the ground construction period, remarkably enhancing the structural integrity of the ground and improving the using performance of the ground.

The invention relates to a 3D printed solid waste concrete member and a preparation method. The concrete member comprises a 3D printed mortar template and a concrete inner core which is filled in thetemplate and can be implanted with reinforcing steel bars, the 3D printed mortar template is made of 3D printing mortar with low shrinkage and high durability, and the concrete filled in the 3D printed mortar template has good fluidity, can realize self-compaction and has small later shrinkage. The 3D printed mortar template can realize quick hardening, early strength and low shrinkage and can beused as a permanent template of a component; the use amount of common wood and steel templates is reduced; the construction speed is accelerated, the internally filled concrete can be matched with reinforcing steel bars for use; the problem that reinforcing steel bars cannot be implanted into a 3D printed component is solved, the concrete inner core and the 3D printed mortar template have good bonding strength, a large amount of glass fiber reinforced plastic solid waste is consumed, solid waste resource recycling and 3D printing intelligent construction are combined, and actual engineering application of 3D printing concrete is promoted.

The invention relates to a concrete pumping antifreezing agent with adjustable performances, belonging to the field of building materials. The concrete pumping antifreezing agent comprises the following materials by weight percent: 28% -42% of water reducing agent, 0.3%-0.7% of air entraining agent, 0.05%-0.07% of fluidizing reagent, 1.5%-2.5% of reinforcing agent and 2.0%-3.0% of antifreezing agent, 1.5%-5.0% of slump loss inhibitor and 45%-65% of water, and the concrete pumping antifreezing agent is a novel pumping antifreezing agent and does not contain any chloride. The concrete pumping antifreezing agent is simple in production process, does not contain alkali and chlorine, and cannot corrode a steel bar. The concrete pumping antifreezing agent has the advantages that the peaceability of concrete is improved substantially, the volume is stable, the water-reducing rate is high, the anti-freezing performance is high, the early-strength performance is obvious, the increasing value of the later-stage concrete strength is high, the adaptability is good, and the like, and has good pumpability in the construction. The concrete pumping antifreezing agent is low in cost, good in performance and has good economical benefits and social benefits.

The invention discloses a method for continuously preparing boron-doped SiO2 aerogel, belonging to the preparation field of novel porous materials. According to the method, by setting a preparation system with the functions of raw material feeding, sol preparation, gel preparation, solvent replacement, gel drying and waste material recycling, a large number of boron-doped SiO2 aerogel can be continuously produced. The method has the advantages that the occupied area of equipment is small, the preparation process is continuous and controllable, the production energy consumption is reduced, theequipment cost is lowered, and the labor cost is lowered. The prepared boron-doped SiO2 aerogel has good mechanical property, light transmittance performance and high-temperature stability.

The invention discloses a preparation method of environment-friendly phase-changed insulated anti-cracking fast-setting spraying mortar. The preparation method comprises the following steps: mixing and stirring common silicate cement and sulfate aluminum cement into mixed cement; modifying expanded perlite by using polystyrene emulsion; adsorbing paraffin into a pore of the expanded perlite by using a reduced pressure adsorption method; coating by using cement; preparing silica-coated polyphenyl particles; preparing silica sol-modified aluminum oxide ceramic powder; uniformly mixing and stirring the prepared remaining blended cement, gypsum, aggregate coated with the blended cement, the silica-coated polyphenyl particles and the ceramic powder, continuously adding sepiolite fibers, polypropylene fibers and a thickening agent, and continuously performing uniform stirring and mixing to obtain the spraying mortar. The spraying mortar is good in thermal insulation, strong in adhesion strength and excellent in mechanical performance.

The invention relates to reduced and reinforced type polycarboxylate having high water-reducing rate and a preparation method thereof. The preparation method comprises the following steps of: (1), carrying out free radical polymerization: adding methacrylic acid, allyl polyoxyethylene ether, acrylamide, maleic anhydride and deionized water into a synthesis reactor according to parts by weight, uniformly stirring and mixing under the protection of nitrogen, heating to 50-90 DEG C, respectively dropping ammonium persulfate aqueous solution and mercaptoacetic acid aqueous solution with the rate of 0.5-8 mL/min, continuously stirring for 2-8 h, and keeping the temperature at 40-80 DEG C for 0.5-5 h; and (2), cooling and neutralizing: adjusting pH to 6-8 after cooling to room temperature so as to obtain the reduced and reinforced type polycarboxylate having high water-reducing rate. The reduced and reinforced type polycarboxylate having high water-reducing rate prepared by the preparation method disclosed by the invention has high water-reducing rate; the surface tension of aqueous solution can be greatly reduced; the reduced and reinforced type polycarboxylate has the obvious function of reducing cement mortar; and, the early and later strength of the cement mortar can be increased with the same water cement ratio.

The invention discloses a preparation method of a fluorine-containing shrink-reduced polycarboxylate water reducing agent. The method particularly includes: 1) preparation of a polycarboxylate water reducing agent prepolymer: under effects of an initiator, a reducing agent and a chain transfer agent, performing a redox radical polymerization reaction to a carbonyl-containing monomer, an unsaturated acid monomer and an unsaturated macro-monomer to obtain a carbonyl-containing polycarboxylate water reducing agent prepolymer; 2) preparation of the fluorine-containing shrink-reduced polycarboxylate water reducing agent: performing a nucleophilic substitution reaction to the carbonyl-containing polycarboxylate water reducing agent prepolymer with a Prakash reagent (TMSCF3) to obtain the water reducing agent. The water reducing agent can significantly reduce surface tension and improve cement dispersibility, is high in shrinkage reducing performance on the basis of high water reduction, is good in compatibility with cement, is low in gas content when being applied to concrete, can effectively improve size stability of concrete and reduce shrinkage cracking and can improve the durabilityand service life of a concrete structure.

The invention provides biomass aggregate recycled concrete and a preparation method thereof, and the biomass aggregate recycled concrete is characterized by comprising cement, broken corncob particlesand a recycled fine aggregate and comprising the components in parts by weight: 8-10 parts of the cement, 1-4 parts of corncob particles, 20-40 parts of the recycled fine aggregate and 8-20 parts ofwater. The volume rate of the corncob particle aggregate in the biomass aggregate recycled concrete is 30%-50%, and the particle size of the corncob particles is 2-10 mm. The preparation method comprises the steps: weighing the cement, the corncob particles, the recycled fine aggregate and the water according to the raw material ratio for later use; uniformly mixing the cement with the recycled fine aggregate, adding water, and stirring to obtain a uniform mixture; adding the corncob particles into the mixture, then compacting while stirring, and making the concrete mixture uniformly; and putting the concrete mixture into a mold, slightly vibrating by a vibrating table, and maintaining at normal temperature for a required number of days. A novel green building material and products thereofare developed by corncobs and construction wastes, and the novel green building material is rich in raw materials, low in cost and suitable for large-scale production.

The invention belongs to the technical field of construction materials, and specifically relates to an inorganic thermal insulation mortar toughened by doping wheat straw fibers and an application method thereof. The inorganic thermal insulation mortar is composed of silicate cement, calcium hydroxide, high calcium fly ash, aluminate cement, wheat straw fiber, polyacrylonitrile fiber, vitrified beads, short-cut wheat straw, butyl benzene emulsion, an air-entrainer, starch ether, and water. The problems of common vitrified bead thermal insulation mortar such as high cost, easy shrinkage and cracking, and the like are solved. The provided inorganic thermal insulation mortar has the advantages of good workability and mechanical properties, small shrinkage, no cracking, excellent thermal insulation performance and fireproof property, safety, durability, and flameproof property, and the fireproof property can reach the A grade. Agricultural wastes such as wheat straw and other solid wastes are fully utilized, the production cost is low, the construction is simple and quick, good economic benefits and social benefits can be generated, and the mortar is suitable for thermal insulation and energy saving engineering of inner/outer walls.

The invention relates to a self-compacting concrete prefabricated hollow plate girder with hybrid fibres instead of reinforcing steel bars and a manufacturing method. The reinforcing steel bars comprise pre-stressed reinforcing steel bars, ribbed steel bars and plain round reinforcing steel bars; the pre-stressed reinforcing steel bars comprise pre-stressed tensile reinforcing steel bars; the ribbed steel bars comprise ribbed longitudinal tensile reinforcing steel bars, ribbed longitudinal compressive reinforcing steel bars, ribbed web plate longitudinal force bearing reinforcing steel bars, and ribbed anti-shear stirrups; the plain round reinforcing steel bars comprise top erecting reinforcing steel bars for fixing the stirrups; the concrete is high-performance self-compacting concrete with the compressive strength of not greater than 50 MPa; the fibres are reinforcing and toughening crude fibres which are mixed in the self-compacting concrete, and comprise end part bending hook-type steel fibres, steel wire-simulated synthetic crude fibres or basalt fibres; the lengths of the fibres are not smaller than 3 cm, and the diameters are not smaller than 0.4 cm. The self-compacting concrete prefabricated hollow plate girder with the hybrid fibres instead of the reinforcing steel bars has the advantages that the concrete shrinkage is small; cracks are reduced; the bonding stress of the concrete and the reinforcing steel bars is high; honeycombs, pitted surfaces and cavities are avoided; the distance between the stirrups is increased; the reinforcing steel bar arrangement precision is improved; the component durability is improved.