43results about How to "Reduce adiabatic temperature rise" patented technology

The invention relates to a ready-mixed concrete with phosphorus slag powder, which is characterized in that the composition ratio and the weight ratio comprise the following parts: 120-150 parts of cement, 100-250 parts of phosphorus slag powder, 0-120 part(s) of fly ash, 0.5-20 part(s) of water reducing agent, 0-0.5 part of air entraining agent, 0-0.02 part of water retention agent, 50-17000 parts of coarse aggregate, 20-9000 parts of fine aggregate and 100-300 parts of water. The invention takes the industrial waste residue i.e. the phosphorus slag powder as the admixture part of the concrete to replace the cement to dope in the ready-mixed concrete, thereby reducing the use amount of the cement, uses the retarding characteristic of the phosphorus slag to reduce the gelled material cost of the concrete and the manufacture cost the of concrete pumping aid, simultaneously gives full play to the characteristic of the phosphorus slag so as to reduce the hydration heat and the adiabatic temperature rise of the concrete, decreases the elasticity modulus and improves the ultimate tensile strain capacity of the concrete, the strength growth rate is high, and the durability is significantly improved; and the invention can changes the waste into the valuable and turns the harmful into the beneficial.

The invention discloses low cementitious material self-compacting concrete. Cement is a main raw material in a cementitious material of the self-compacting concrete; and if the cement consumption is high, overhigh concrete shrinkage is easily caused due to overhigh hydration heat of the cement, which is unfavorable for concrete crack control and concrete durability improvement, and problems such as disintegration, bleeding and the like easily occur. An additive XAMC is added into the concrete formula and can adsorb onto surfaces of particles to form a close adsorption layer so as to prevent the particles from flocculating and aggregating to realize the dispersion and stabilization function. Water-washing superfine sand which is rich in resources replaces partial mineral admixture, the low cementitious material self-compacting concrete can meet the basic requirement of high strength concrete by adding the XAMC under the condition of reducing cement consumption, and has obvious thickening and water retaining functions; concrete mixtures do not bleed or disintegrate, the homogenization and workability of the concrete are improved, and the concrete has important significance for saving energy and reducing emission.

A high-activity superfine additive for concrete is prepared from at least two of steel slag, flyash, granular slag of blast furnace and phosphur slag, and gypsum through grinding, proportional mixing and further pulverizing. Its advantages are high specific surface area (more than 400 sq.m/kg), high activity, and low heat release.

The invention discloses high strength silica powder concrete and a construction technology thereof. The optimal selection of raw materials and the optimal design of mixing proportion are used as footholds, the measure of mixing pulverized fuel ash and silica powder with selected moderate-heat or low heat cement replaces other measures of mixing composite high efficiency water reducing agent, fibers, and the like with parts of cement, so as to reduce the use level of the cement as much as possible and to reduce the adiabatic temperature rise of the cement, thereby greatly overcoming the disadvantages of the silica powder, improving the early-age cracking-resistance property of the cement, and giving full play to the gap filling efficacy and the pozzolanic reaction property of the silica powder. While strengthening the intensity of the concrete, the invention effectively avoids the technical problem of early-age cracking during the silica powder construction.

The invention relates to a mineral admixture concrete. Mineral admixtures are used as concrete cementitous materials, common concrete and a complex of gypsum and sodium sulfate are added and used as activity excitants so as to coordinate the combined action of naphthalenesulfonate formaldehyde condensate and a crude anthracene sulfonate superplasticizer, and the high-efficiency concrete is prepared. Compared with the prior art, the excitants in the invention has the advantages that early excitation effect is good, mixing amount is less, the early or later strength and durance of the concrete can be greatly improved, the concrete dosage is reduced by 5-20% under the condition of maintaining the strength and workability of the concrete not to be changed, and the gypsum and sodium sylfate are both industrial byproducts with low costs. In the invention, concrete plaster is mixed in advance by using a secondary feeding method, residual materials are added in the mixed concrete plaster, and the strength of the concrete is improved while reducing the abrasion of coarse aggregates on equipment. The concrete has the advantages of good workability and less bleeding, is convenient for construction, and can be applied to large-volume concrete engineering, underground engineering, seaport engineering and the like.

The invention relates to a concrete additive and discloses a concrete composite additive capable of optimizing a hydration heat release process of cement, which is prepared from the following raw materials in percentage by mass: 65 to 75 percent of naphthalene sulfonate-formaldehyde condensation product, 9 to 15 percent of lignosulfonic acid calcium salt, 8 to 10 percent of sodium gluconate and 8 to 10 percent of sucrose. When the additive is used, the hydration heat release of cement has the characteristic of two peaks and equal peak values. When other conditions are the same, the hydration heat half age of the cement mixed with the additive is three times longer than cement mixed with a naphthalene sulfonate water reducer and a concrete thermal-insulation temperature rise at a 7d age is reduced by about 7 DEG C; and the additive allows a cooling measure of introducing water to concrete to play a better cooling role, reduces the temperature rise peak value of the concrete by about 4 DEG C, ensures a remarkable cooling effect and has a great significance for the temperature control and cracking prevention of concrete. In addition, when the product provided by the invention is added, the pressure strength, working performance, durability and the like of concrete are all improved obviously.

Shrinkage-reducing anti-cracking pavement cement concrete and a preparing method thereof are disclosed. The cement concrete is prepared from water, cement, fly ash, basalt fibers, light aggregate, broken stone, sand and a water reducing agent in a mass ratio of (180-200):(400-410):(40-50):(2.65-5.3):(229-286):(465-559):(830-850):(4.1-4.5). The light aggregate is uniformly dispersed in the concrete, the concrete is not liable to crack, adhesive force between the fibers and cement slurry is high, microcrack development is slow, and the concrete has high fatigue resistance and tension resistance.

The invention provides a modified phosphorous slag powder, a concrete prepared from the modified phosphorous slag powder and a preparation method of the concrete, and belongs to the technical field of concrete preparation. The modified phosphorous slag powder comprises a phosphorous slag powder, an organic salt and cationic starch. The organic salt and the cationic starch are used for modifying the phosphorous slag powder in stead of common chemical excitation carried out on the phosphorous slag by using an inorganic alkali activator in the prior art; when the modified phosphorous slag powder is used for preparing the concrete, the dosage of the modified phosphorous slag powder accounts for 38-70wt% of the total amount of the cementing material; the 3d compressive strength of the concrete ranges from 14.5 to 33.5MPa, and the 28d compressive strength of the concrete ranges from 30.6 to 77.3MPa, and the stability of the concrete is good; the utilization rate of the phosphorous slag powder is greatly reduced while the cost of the concrete is reduced, and therefore, the environmental pollution problem caused by the phosphorous slag can be reduced.

The invention relates to the field of civil engineering, in particular to a gradient type concrete water pipe control system and control method. According to the gradient type concrete water pipe control system and control method, in the temperature rising period of concrete, the center temperature of the concrete can be reduced as quick as possible with the highest efficiency, the temperature can be reduced by 20-25 DEG C at maximum, adiabatic temperature rising of the concrete is equivalently reduced, and the cracking risk is reduced; in the temperature decreasing period of the concrete, the temperature decreasing speed of the concrete can be reduced by adjusting the water temperatures of water pipes in different positions of the concrete, the temperature decreasing speed of the concrete is smaller than or equal to 3.0 DEG/day, impact of contraction deformation is reduced, and the cracking risk is reduced; and meanwhile the concrete water pipe control system can automatically read the temperatures of temperature measuring points inside the concrete and adjust the water inlet temperatures of the water pipes according to the actual temperatures of the parts inside the concrete, the temperature gradient among the interior, middle and exterior of the concrete and air is reduced to the maximum extent, and the cracking risk is reduced.

The invention relates to a prefabricated duplex block concrete construction mixing ratio which is prepared by uniformly stirring the following raw materials according to the following ratio through a concrete stirring machine, wherein the bulk density is 2300-2500kg/m<3>, and the specific mixing ratio is as follows: 350-370kg/m<3> of cement, 770-790kg/m<3> of sand, 620-650kg/m<3> of broken stones 1, 415-435kg/m<3> of broken stones 2, 8.80-9.20kg/m<3> of a polycarboxylic high-performance water reducer, 60-80kg/m<3> of fly ash and 160-170kg/m<3> of water. A manufacturing technology comprises the following steps: sequentially adding the broken stones 1, the broken stones 2, the cement, the fly ash, the sand and the water in a stirring tank, and finally adding the polycarboxylic high-performance water reducer; and stirring for 90-120s after addition is finished, and finally forming a mixture with the 28d strength greater than or equal to 40MPa, the collapsing degree being 140-160mm and the out-of-machine temperature of a mixture lower than 30 DEG C. The prefabricated duplex block concrete construction mixing ratio can solve the problem of concrete quality such as concrete bubbles, cracking, cracks or the like and is suitable for regions with the temperature being 30-40 DEG C.

The present invention discloses a preparation process of special external-adding hydraulic light burning magnesium oxide dam concrete having an adjustable expanding process, wherein the adding amount, the fineness compostion, the active index, the calcining temperature and the calcining thermal insulation time of the special hydraulic light burning magnesium oxide expanding agent are adjusted so as to adjust and control the expanding-age process of the external-adding hydraulic light burning magnesium oxide dam concrete. The invention further discloses a construction method of the special external-adding hydraulic light burning magnesium oxide dam concrete having the adjustable expanding process. According to the present invention, the expanding process of the special external-adding hydraulic light burning magnesium oxide dam concrete can be adjusted, such that the expanding amount can be compensated according to the requirement of the dam concrete so as to achieve the accurate control, significantly improve the quality of the project, reduce the temperature control measures, save the temperature control cost, save the investment, and improve the benefits of the project.

The invention belongs to the field of concrete and particularly discloses low thermal micro-expansive cement based radiation shielding concrete and a preparation method thereof. The low thermal micro-expansive cement based radiation shielding concrete is prepared from the following materials in parts by weight: 280-320 parts of cement, 900-1200 parts of fine aggregates, 1200-1500 parts of coarse aggregates, 10-20 parts of a neutron absorber, 0.4-0.6 part of a water reducer and 140-160 parts of water. The concrete accords with the strength requirements for C30 concrete without the segregation phenomenon, is good in slump and divergence, has the bulk density ranging from 2800 kg.m<3> to 2900 kg.m<3>, has the 28d restrained expansion rate ranging from 0.004 percent to 0.007 percent under thewater cultivation condition, has the characteristics of excellent working performance, good radiation shielding performance, low cost and the like at the same time, solves the problems of easiness insegregation, poor homogeneity, poor construction performance and the like of the traditional radiation shielding concrete, is further beneficial to meeting the requirements for the special performanceincluding non shrinkage, micro expansion, low hydration heat and the like of the radiation shielding concrete and is very suitable for large-size radiation shielding concrete engineering.

The invention relates to the technical field of buildings, and provides a large-span prestressed bealock beam, a bealock structure, a maritime work pool and a construction method. The large-span pre-stress bealock beam comprises a pre-stress supporting structure which is arranged in the first direction and connected with an environment structure, and the pre-stress supporting structure is a pre-stress beam; the coping beam is connected with the prestress supporting structure, and at least one plane of the coping beam is arranged to be an assembling face of the bealock beam. The large-span pre-stress bealock beam has the beneficial effects that the large-span pre-stress bealock beam is divided into the pre-stress supporting structure and the coping beam, so that the influence of deformation of the pre-stress supporting structure on the coping beam is reduced to the greatest extent, and the flatness of the assembly surface of the coping beam is improved; therefore, the high-precision requirement of the maritime work pool large-span bealock beam is met.

The invention discloses a special grinding aid for maritime work cement and a preparation method of the special grinding aid. The special grinding aid for maritime work cement is prepared from the following raw materials: 5-9% of grinding aid mother liquor, 13-18% of an industrial salt, 3-9% of a superplasticizer, 7-15% of slag powder, 3-5% of limestone powder, 3-8% of silica fume and 36-66% of fly ash; specifically, the percentages are mass percentages. By using the superplasticizer with high dispersion performance, cement particles can be highly dispersed, and in addition, through dispersionpermeation, charges carried by the cement particles are neutralized, so that the agglomeration phenomenon is reduced. Slag powder, limestone powder and fly ash are used, so that hydration heat of marine cement can be remarkably reduced, adiabatic temperature rise in concrete is reduced, temperature stress caused by internal and external temperature difference is reduced, generation of concrete temperature cracks is prevented, the overall integrity of a concrete structure is guaranteed, therefore, the corrosion resistance and the durability of the concrete structure are effectively improved.