679 results about "Slump" patented technology

A cement dispersant having excellent ability to prevent slump loss and high water-reducing property which comprises a polycarboxylic acid type polymer having a specific molecular weight distribution, a method for the production thereof, and a cement composition using the dispersant are provided. The cement dispersant comprises as a main component thereof a polycarboxylic acid type polymer (A), having a weight average molecular weight in the range of 10,000 to 500,000 in terms of polyethylene glycol determined by gel permeation chromatography, and having a value determined by subtracting the peak top molecular weight from the weight average molecular weight in the range of 0 to 8,000.

The present invention discloses a low shrinkage anti-cracking C60 grade self-compacting bridge tower concrete based on internal curing, shrinkage compensating and toughening, wherein the low shrinkage anti-cracking C60 grade self-compacting bridge tower concrete is prepared from the following raw materials: cement, fly ash, mine powder, an expander, an AN-ICA internal curing agent, crushed stone, river sand, polyacrylonitrile fibers, micro-scale modified degreasing cotton cellulose, a cement slurry microstructure regulation agent, water and an ultra-dispersed water-reducing and shrinkage-reducing superplastic admixture. According to the present invention, the initial slump is more than or equal to 230 mm, the expansion degree is more than or equal to 630 mm, the 28 d compressive strength is more than or equal to 70 MPa, the 28 d splitting tensile strength is more than or equal to 5.8 MPa, the toughness index I5 is more than or equal to 3.0, the 28 d self-shrinkage is less than 100*10<-6>, the 28 d dry shrinkage rate is less than 150*10<-6>, the carbonization grade achieves T-IV, the anti-cracking grade achieves L-V, the product has characteristics of excellent mechanical property, excellent cracking resistance and excellent durability, and the difficult problems of high cement and cementing material material consumption, large shrinkage and easy cracking of the bridge tower concrete at the current stage can be solved.

A lightweight ready-mix concrete composition that contains 8-20 volume percent cement, 11-50 volume percent sand, 10-31 volume percent prepuff particles, 9-40 volume percent coarse aggregate, and 10-22 volume percent water, where the sum of components used does not exceed 100 volume percent. The prepuff particles have an average particle diameter of from 0.2 mm to 8 mm, a bulk density of from 0.02 g/cc to 0.64 g/cc, an aspect ratio of from 1 to 3. The slump value of the composition measured according to ASTM C 143 is from 2 to 8 inches. After the lightweight ready-mix concrete composition is set for 28 days, it has a compressive strength of at least 1400 psi as tested according to ASTM C39.

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.

A cement admixture object of the present invention can make slump-retaining ability excellent to retain fluidity and, at the same time, can realize a viscosity of cement compositions so that work becomes easy at a field handling them, can make the state of a cement composition better. The present invention relates to a cement admixture which comprises a polycarboxylic acid copolymer having a polyalkylene glycol side chain, said polycarboxylic acid copolymer being constituted of two or more species of copolymers with different acid values, and at least one of said two or more species of copolymers with different acid values having an oxyalkylene group containing 3 or more carbon atoms.

The invention discloses a micro-collapse concrete of rolled concrete dam and constructing method, which comprises the following parts: cement, coal ash, rough aggregate, fine aggregate, slow setting high-effective dehydragent, air-entrainer and water, wherein the slump of allocated concrete is less than 0. 5cm with consistency value VC at 1-3s; the allocation of the micro-collapse concrete is similar to internal rolling concrete of dam through adding some gelling material slightly, which saves cost with high quality obviously.

The invention discloses a method for reinforcing recycled aggregate concrete by changing a stirring technology, and belongs to the field of building materials. The method comprises the following steps that (1) solid waste is crushed via a jaw crusher, and then sieved and assembled into a recycled coarse aggregate meeting a 4.75-25mm continuous grading requirement; and (2) cement and water with 50% of the total water consumption are mixed and stirred for 30-60s; the recycled coarse aggregate is added and stirred for 30-60s; natural coarse and fine aggregates are added and stirred for 30-60s; the residual 50% of water is added and stirred for 30-60s; the slump of a discharged material is measured; and a test block is prepared. Compared with conventional stirring, the stirring technology adopted by the method can wrap and form low-water-cement-ratio cement mortar on the surface of the recycled coarse aggregate, exerts repair and reinforcing effects on a weak area on the surface of the recycled coarse aggregate, and reinforces interface transition areas among the recycled coarse aggregate, the natural aggregates and the cement mortar, so that the compressive strength of the recycled concrete is improved.

The invention discloses a sliding formwork parallel moving concrete lining machine and a construction method, a machinery of the invention comprises a walking mechanism, a trimming lifting device, a tamping device and a stretch main frame, wherein the main frame is hinged with a top frame and a bottom frame, the top frame is arranged on the upper portion of the main frame, the bottom frame is arranged on the lower portion of the main frame, a sliding orbit on the main frame is engaged with a sliding template, the sliding template is driven by a winding mechanism which is arranged on the top portion of the sliding template. The construction method using the invention comprises the processes of machinery installment and location, elevation adjustment, emptying, tamping, sliding template lifting and pressing surface and the like, which is construction by course, segmentation jolting and a segmentation pressing surface from upper to lower until a slope top and a slope shoulder. After an active section is completed, the lining of next working position is integrally moved. The width of the work surface of the invention is above 2m, the slope length is 3-30m, the slope degree is 1/0.1-1/1.99, the collapsed slump is smaller than 8, the inner portion of a concrete surface is tight, the surface is even and smooth, staggered platform and pockmark do not exist, the project progress is rapid, and the efficacy is 3-12 times of the sliding template.

The invention provides a composite antifreezing agent and an antifreezing pumping agent. The composite antifreezing agent is a mixture prepared from a salt component and an organic solvent component, wherein the salt component is a mixture of calcium nitrate, calcium formate and sodium thiosulfate; the organic solvent component is alcohol. The invention further discloses the antifreezing pumping agent with the antifreezing agent. The composite antifreezing agent is a liquid antifreezing agent compounded from organic and inorganic early strength components and antifreezing components, and is good in antifreezing effect, and moreover the later strength of concrete constructed in winter can be effectively improved. The antifreezing pumping agent with the antifreezing agent is good in antifreezing effect, good in adaptability with cement, low in slump time loss of concrete and good in antifreezing effect, and the anti-pressure strength of the composite antifreezing agent is far greater than the standard requirements under the condition of the provided temperature of minus 10 DEG C. The composite antifreezing agent is applicable to concrete pumping construction in northern areas in winter, can be applicable to commercial premixed pumping concrete, and can be also applied to on-site mixed pumping concrete.

The invention discloses a preparation method of a slow-release microcapsule concrete admixture. The method comprises the following processes: stirring and dispersing a porous carrier into a concrete admixture solution; fully soaking, centrifuging and filtering, and drying to obtain the slow-release microcapsule concrete admixture. When the porous carrier is fully soaked in the concrete admixture solution, one part of concrete admixture molecules enter the pores of the porous carrier and the other part of concrete admixture molecules are adsorbed on the surface of the carrier particle; the two parts of concrete admixture molecules are reserved in the porous carrier after being filtered an dried, so as to form the slow-release microcapsule concrete admixture. In addition, the invention also discloses a slow-release microcapsule concrete admixture. The concrete admixture can keep the flowing property of the concrete mixture, so that the slump of the concrete mixture is not lost within 5 hours, concrete segregation and bleeding are reduced, and the compactness, the strength and the durability of the concrete are improved.

This invention relates to the field of concrete super-retarding reagents that are compatible with all kinds of concrete water reducers. The super-retarding reagent in this invention has a mass-fraction composition as follows: 6~35% ethylene polyamine alkyl phosphonic acid or its salt, 5~15% phosphonobutane tricarboxylic acid and 50~90% water. The super-retarding reagent is compatible with different kinds of water reducers and cement, and can greatly reduce the loss of concrete mixture slump. The super-retarding reagent performs extraordinary retarding activities, and concrete solidification time can be adjusted to 3~150 hours by modulating product composition and dosage according to actual engineering demand.

The invention discloses a high-water-retaining-property shield construction premixed synchronous grout material which comprises cement, coal ash, admixture, bentonite, fine sand, additives and water. The additives mainly comprise non-ionic cellulose ether, carbohydrate, polycarboxylic acid slump retaining agents, starch ether and magnetic hydrotalcite. The high-water-retaining-property shield construction premixed synchronous grout material has the advantages that the optimized admixture, the bentonite, the fine sand with the fineness modulus being 1.6 and the additives special for mortar are jointly used in the shield construction premixed synchronous grout material, the fluidity loss of the adjusted grout material is less than or equal to 30mm in 6 hours, bleeding rate is reduced to be lower than or equal to 3.0%, and sedimentation after a vibration test is less than or equal to 20mm; due to the fact that the magnetic hydrotalcite is added, the grout material can reduce construction noise during stirring and absorb heavy metal ions to prevent heavy metal in the mortar from causing secondary pollution on the basis that the original physical properties are kept.

The invention discloses a device for testing slump of a concrete mixture. The device comprises a lower electrical push rod mechanism, a middle electrical push rod mechanism, an upper electrical push rod mechanism, a slump cylinder and a spiral movement mechanism, wherein the lower electrical push rod mechanism comprises a lower base, the lower base is arranged on ground, and a lower electrical push rod is arranged on the lower base; the middle electrical push rod mechanism comprises a middle base, and a middle electrical push rod is arranged on the middle base; an extending rod of the middle electrical push rod is upwards connected with an upper base, and the slump cylinder is connected with the upper base; the upper electrical push rod is positioned just above the slump cylinder, and an extending rod of the upper electrical push rod is vertically and downwards connected with the spiral movement mechanism; the spiral movement mechanism is connected with a vertical vibration bar. The invention also discloses a use method of the device for testing the slump of the concrete mixture. The device has the advantage that the artificial vibration is not needed, so that the error due to theartificial vibration is avoided, and the stability and accuracy in testing are improved.