28 results about "Initial strength" patented technology

The microbial remediation ceramsite comprises microorganisms, nutrient substances, modified porous slow-release Ca < 2 + > ceramsite and a cement-based protective shell, the microorganisms and the nutrient substances are loaded in the modified porous slow-release Ca < 2 + > ceramsite, and the cement-based protective shell wraps the outer surface of the modified porous slow-release Ca < 2 + > ceramsite. The surface of the ceramsite is modified by an aggregation-crosslinking method, and the modified microbial ceramsite carrier has higher microbial loading capacity and better stability under the dual actions of physical adsorption and valence bond combination, so that the repair effect of the ceramsite on cracks is further ensured; the cement-based protective shell adopts epoxy resin, so that the cylinder compressive strength of the ceramsite is improved, and microorganisms and nutrient substances are protected from being damaged by a high-alkalinity environment; the cement-based mixed powder is selected to enhance the interface adhesive force between the ceramsite and cement concrete, the sulphoaluminate cement in the mixed powder ensures the strength of the ceramsite in the early stage, and the fly ash, the silica fume, the nano-silica and other materials enable the later strength of the ceramsite to be continuously increased.

A full solid-waste micro-expansive concrete and its preparation method are provided, and relate to the field of concrete material technologies. The full solid-waste micro-expansive concrete includes the following components in parts by weight: 920-1060 parts of a coarse aggregate, 460-582 parts of a fine aggregate, 11-19 parts of an expansive agent, 389-512 parts of a modified solid-waste-based cementitious material, and 231-268 parts of water. The coarse aggregate is coal gangue. The fine aggregate is waste ceramic. The modified solid-waste-based cementitious material includes a solid-waste-based clinker, modified polyvinyl alcohol, and a modified anion exchange resin. The solid-waste-based clinker is prepared from the coal gangue, carbide slag, and desulfurization gypsum. The expansive agent is obtained by calcining the carbide slag. The concrete prepared can ensure the initial strength of the concrete, and guarantee continuous micro-expansion in the later stage, compensating for shrinkage and thereby increasing the overall strength of the concrete.

The present invention provides a water-reactive asphalt cold patch material, a preparation method and an application, which comprises the following components, calculated by mass percentage: 97-98% of asphalt pavement milling material, 0.5-1% of old asphalt activator and 1.5-2.5% of cold patch agent; the strength of the water-reactive asphalt cold patch material of the present invention is mainly derived from the solidification reaction of the old asphalt activator and the active ingredients in the cold patch agent under the action of water. Therefore, compared with traditional asphalt cold patch material, the water-reactive asphalt cold patch material of the present invention has higher initial strength, and the repaired pavement has better durability after being opened to traffic.

To provide a low-carbon type concrete: capable of reducing CO2 (carbon dioxide) emissions; capable of securing initial strength required for application to general structures; having reduced shrinkage compared with conventional concrete; capable of further promoting carbon fixation after being put into service; and having high durability.SOLUTION: A low-carbon type concrete comprises cement, an admixture, aggregate, nitrite, urea, and water, wherein the admixture includes blast furnace slag fine powder and / or fly ash.SELECTED DRAWING: None

This invention relates to the field of refractory materials technology, and more particularly to a cementless magnesia castable and its application method. The castable consists of aggregate, matrix material, and a water-reducing agent; the aggregate is 60-80 parts of magnesia particles; the matrix material is: fine magnesia powder, active α-Al₂O₃ micro powder, sintered corundum powder, silica micro powder, and aluminum-based metal microcapsules. The application method of the cementless magnesia castable is as follows: the water-reducing agent and matrix material are mixed evenly to obtain a premixed matrix material; the aggregate and premixed matrix material are stirred evenly, water is added and wet-mixed to obtain a slurry; the evenly mixed slurry is poured into a mold, vibrated to form the slurry, and then cured. This cementless magnesia castable exhibits certain initial strength, excellent high-temperature performance, excellent resistance to slag erosion and thermal shock, and a long service life, making it widely applicable in tundishes and ladles.

The invention relates to the technical field of concrete detection equipment, in particular to a detection device for quickly detecting the initial strength of concrete by embedding a template system, which comprises independent steel templates which are used as detection pressure units and are separately arranged on the inner side of a slip form steel template, and the independent steel templates are in direct contact with a concrete surface; the unit contact area of the independent steel templates is defined as S; the limiting device is assembled between the slip form steel template and the independent steel template and is used for keeping the independent steel template in a non-working state flush with the inner side of the slip form steel template; and the electric press is in transmission connection with the independent steel template. According to the detection device for rapidly detecting the initial strength of the concrete by embedding the template system, the independent steel template is in direct contact with the concrete in the template, and the strength data of the concrete body is directly obtained in a detection mode of penetration at a specific depth in unit area; and the problem of deviation between the mortar strength and the concrete body strength is avoided.

The invention discloses a method, a device and equipment for analyzing the opening strength of a composite material plate and a medium. Comprising the steps that the safety margin of an unopened composite material plate is calculated, and when the safety margin is smaller than or equal to 0, the reinforcing offset amount is determined according to the safety margin; the reinforcing strain of the unopened composite material plate is calculated in combination with the reinforcing offset; calculating the unreinforced hole edge strain of the opened composite material plate according to the preset opening size, and analyzing the opening strength of the composite material plate according to the reinforced strain and the unreinforced hole edge strain. By means of the safety margin, whether the initial strength of the composite material plate meets the requirement or not can be judged, the strengthening offset amount is quantitatively determined based on the safety margin, and design blindness is avoided. By acquiring the strain state of the unopened plate after reinforcement, deviation of subsequent strength analysis caused by lack of strain data after reinforcement is avoided. By analyzing the reinforced strain and the unreinforced hole edge strain, the actual strength of the opening reinforced structure can be evaluated, the workload is reduced, and the analysis efficiency is improved.

To provide a hydraulic composition having good initial strength development and small dry shrinkage even when using a blast furnace cement with large content of a blast furnace slag fine powder, a hydraulic composition that can also be applied to a road concrete for pavement, and a technology for manufacturing concrete that can suppress a used amount of Portland cement and can reduce a discharge amount of carbon dioxide.SOLUTION: In a hydraulic composition containing a cement composition containing Portland cement and a blast furnace slag fine powder and a cement admixture containing calcium aluminate and anhydrous gypsum, a content of the blast furnace slag fine powder is 40-70 mass% in the cement composition, and a content of the cement admixture is 20-40 pts.mass to the sum total 100 pts.mass of the cement composition and the cement admixture.SELECTED DRAWING: None

The present application belongs to the technical field of geotechnical engineering support, and discloses a self-drilling anchor rod supporting system and method based on adjustable delayed expansion slurry and dynamic pressure splitting grouting cooperation. The present application forms a coated calcium oxide expanding agent by using a specific material, and delays the expansion burst time to after the slurry has initial strength and the orifice is locked. The limited expansion force not only compensates for the condensation of the cement base, but also is converted into a powerful radial compressive stress, which realizes "first extrusion and compaction, then cementation and solidification" for the broken surrounding rock, and greatly improves the overall stability of the composite bearing body. The dynamic pressure splitting grouting process of introducing a specific frequency pressure is used to open the crack tip and communicate other cracks by using alternating pressure. At the same time, the hydrophobic coating of the coated calcium oxide expanding agent physically isolates the core expansion component during the grouting stage, avoiding the viscosity surge and invalid expansion caused by the premature hydration of conventional expanding agents. The two cooperate to ensure the excellent permeability and uniform diffusion capacity of the slurry in the deep micro blind end cracks.

The purpose of the present invention is to provide an organic calcium acid that, when used with an amorphous aluminosilicate powder, is capable of improving initial strength and long-term strength. The organic calcium acid is used with a curable composition containing amorphous aluminosilicate powder having a BET specific surface area of 1.0 m2 / g or greater. The amorphous aluminosilicate preferably contains at least one of metakaolin and allophane.

The application discloses a manufacturing method of pre-hardening-free high manganese steel frog, and relates to the technical field of turnout rail pieces. The application processes the austenitic high manganese steel frog, so that the specific regions of the nose rail and the corresponding wing rail are higher than the working surface by 50-80 mm, and the transition slope gradient is less than 60 degrees. The above-mentioned high regions are forged by adopting three-stage forging at 1180-1200 DEG C, the reduction of the first and second forging is controlled, and the forging is kept warm. The third forging makes the high regions flush with the working surface, and finally, water cooling is performed to obtain the pre-hardening-free high manganese steel frog. The application does not need pre-hardening treatment, improves the frog performance through structural design and forging process, forms a heterogeneous structure on the surface, significantly improves the initial strength of the frog under the premise of maintaining the plasticity and toughness of the frog, prolongs the service life, and is suitable for harsh service environments such as high-speed heavy-load railways, plateau railways and the like.

The present invention provides a low-carbon mortar or concrete composition and a method for producing mortar or concrete that exhibits excellent initial strength development, durability, and productivity. [Solution] The composition contains a binder made of blast furnace slag fine powder and rapid-strength Portland cement, water, fine aggregate including blast furnace slag fine aggregate, and a nanoparticle-based rapid-strengthening agent made of calcium silicate hydrate nanoparticles. The mortar or concrete composition is mixed while it is still wet, then wrapped in an insulating material and cured without applying heat to produce mortar or concrete.

To provide a hydraulic composition excellent in initial and long-term strength development even when blast furnace cement including blast furnace slag fine powder is used, and to provide high-strength concrete, excellent in surface layer quality and durability.SOLUTION: There is provided a hydraulic composition including a cement composition containing Portland cement and blast furnace slag fine powder, and a cement admixture containing calcium aluminate and anhydrous gypsum, in which the content of the blast furnace slag fine powder is 5 mass% or more and less than 40 mass% in the cement composition, and the content of the cement admixture is 20 to 40 pts.mass relative to 100 pts.mass of the total of the cement composition and the cement admixture.SELECTED DRAWING: None

The invention belongs to the technical field of oil-gas well stability monitoring, and particularly relates to a simulation monitoring method for oil-gas well stability influenced by mining, which comprises the following steps: arranging a simulation oil-gas well shaft composite structure according to the relative position of an actual production oil-gas well and a coal face, and the structure comprises a protection casing, a production casing and well cementation cement; strain is monitored through a distributed optical fiber sensor, displacement is monitored through a GNSS telemetering station, air tightness is tested through a pressure gauge, and deformation is detected through a caliper. And comprehensively evaluating the stability of the oil and gas well based on comparison of monitoring data and initial strength parameters. According to the invention, the problems of incapability of real-time monitoring and poor early warning performance of a traditional method are solved, and the monitoring precision and the engineering safety are remarkably improved.

The invention discloses a bridge expansion joint low-carbon quick-hardening early-strength repairing material and a construction method thereof, and belongs to the technical field of engineering construction. The low-carbon quick-hardening early-strength repairing material for the bridge expansion joint is prepared from the following raw materials in parts by weight: sulphoaluminate cement, Portland cement, calcined shell powder, fly ash and silica fume. Reinforced modified fibers, modified shell powder and a water reducing agent. By treating the shell powder and the reinforced fibers, the setting time and the initial strength maturation period of the concrete can be shortened, so that the construction speed and efficiency are improved, the repairing and reinforcing process of the bridge expansion joint is accelerated, the construction period is shortened, and the engineering cost is reduced. The low-carbon quick-hardening early-strength repairing material for the bridge expansion joint can improve the strength and durability of a repairing layer and effectively guarantee safe operation of a bridge, and meanwhile, quick-hardening construction can shorten the traffic interruption time and guarantee quick and normal traffic of a road.

The utility model relates to a novel foundation reinforcement pile head regulator which comprises a pile foundation, a raft plate, a pile top design elevation position and a main rib arranged on the inner side of the pile foundation, a cushion layer is arranged on the periphery of the side of the pile foundation, and a high-strength grouting material layer is arranged on the top of the pile foundation. A base is placed in the center of the top face of the high-strength grouting material layer, structural adhesive adheres to the surface of the high-strength grouting material layer on the top of the pile foundation and the base, the base of the rigidity adjuster is fixed through the high-strength grouting material layer and the structural adhesive, the rigidity adjuster is arranged on the upper side of the base in a spot welding mode, and therefore the purposes of saving materials, shortening the construction period and reducing the engineering cost can be achieved; and the quality control is relatively easy because the traditional secondary pouring of the concrete anchoring base needs about 24 hours for demolding, and the high-strength grouting material only needs about 1 hour to have the initial strength, so that the construction efficiency is greatly improved.

To provide a hydraulic composition that is made to improve initial strength development when substituting blast furnace slag for a part of cement.SOLUTION: The present invention relates to a hydraulic composition that consists of Portland cement, blast furnace slag, crystalline layered sodium silicate, has the Portland cement of 30 pts.mass or more and less than 40 pts.mass, the blast furnace slag of over 60 pts.mass and 70 pts.mass or less (where, a total of the Portland cement and the blast furnace slag is 100 pts.mass), and the crystalline layered sodium silicate of over 0 mass% and 12 mass% or less per a whole composition.SELECTED DRAWING: None

The application discloses a kind of super high strength super high toughness concrete and its preparation method, the process of the preparation method is: based on the design of concrete slurry mix proportion of close packing theory, select the slurry formula of initial strength not less than 60MPa with fluidity not less than 180mm as benchmark mix proportion;Select steel fiber as end hook type steel fiber, utilize board or steel plate according to the size requirement of test piece to carry out formwork support, then end hook type steel fiber is laid in the range of support with steel fiber cage, steel fiber is staggered in the range of support to form macroscopic steel fiber space skeleton;According to benchmark mix proportion, slurry is prepared, then slurry is infiltrated into the steel fiber space skeleton built, after slurry completely infiltrates steel fiber space skeleton, vibration;After that, curing formwork is removed to obtain super high strength super high toughness concrete.Solve the problem of agglomeration effect caused by too high fiber content, meet the unified requirement of concrete material strength and toughness in engineering.

The invention belongs to the technical field of pavement paving materials of roads, and particularly relates to a cold patch material for cold paving, a paving method and application of the cold patch material. The cold patch material is characterized by being prepared from the following raw materials in parts by weight: 20 to 30 parts of matrix asphalt, 10 to 20 parts of waste rubber particles, 1 to 2 parts of 3MK520 primer, 10 to 15 parts of solvent oil, 20 to 30 parts of mineral powder, 50 to 60 parts of aggregate, 1 to 3 parts of quick setting agent and 5 to 8 parts of water. The invention also discloses an application of the 3MK520 primer in preparation of a cold patch material for cold paving. The solvent oil is petroleum ether or xylene; the quick-setting agent is an epoxy modified quick-setting agent; and 90 # matrix asphalt. The prepared cold patch material for cold paving has the characteristics of rapid forming strength, high initial strength, long service life and rapid traffic after paving, is suitable for paving in different seasons, and is free of excavation, base oil and edge sealing in the paving process, so that the paving process is greatly simplified, the paving labor intensity is reduced, and the cold patch material for cold paving greatly reduces exhaust emission.

Provided is a cement composition which contains a blast-furnace-slag fine powder and, despite this, is less apt to crack, does not have a large increase in temperature due to hydration reaction, and shows an excellent initial strength development.　The cement composition comprises portland cement, a blast-furnace-slag fine powder, and fly ash, wherein the blast-furnace-slag fine powder satisfies all of the following requirements (1) to (3) and the proportions of the portland cement, the blast-furnace-slag fine powder, and the fly ash are 25-45 mass%, 35-65 mass%, and 10-20 mass%, respectively, relative to a total of 100 mass% of the portland cement, blast-furnace-slag fine powder, and fly ash. Requirement (1): The blast-furnace-slag fine powder has a Blaine specific surface area of 4,100-4,500 cm2 / g. Requirement (2): The blast-furnace-slag fine powder has a basicity of 1.80-2.00. Requirement (3): The blast-furnace-slag fine powder has an MgO content of 3.0-6.0 mass% and an SO3 content of 1.5-2.5 mass%.

The application discloses a reinforcing method suitable for a large-diameter shield tunnel of a CT joint segment in a soft soil layer, which comprises the following steps: firstly, according to the stratum properties, anchoring and anti-floating needs, the setting range of a reserved grouting hole on a segment, the length of a grouting pipe and the expansion position of a grouting bag are planned; secondly, a high-performance engineering plastic pipe is pre-buried in the grouting hole, and a plain concrete protective layer is reserved between the outer end of the engineering plastic pipe and the segment outer skin; thirdly, a buried steel pipe with a grouting bag is chiseled and installed in the engineering plastic pipe, a grouting pipe is installed in the buried steel pipe, and the buried steel pipe and the grouting pipe are respectively sleeved with annular neoprene rubber plates as a mud-proof water-stopping device at the grouting hole; fourthly, the grouting pipe is used for "retreating type" grouting, and the grouting bag is filled from outside to inside; when the grouting slurry reaches the initial strength, the grouting pipe is pulled out and the port of the buried steel pipe is blocked; and finally, after the shield segment is assembled and the shield tail is moved out by a distance of at least the outer diameter of the shield tunnel, the stratum surrounding the shield tunnel is reinforced within 24 hours.

The invention relates to a manufacturing method of gear steel for cold forging machining, and belongs to the technical field of steel preparation. The embodiment of the invention provides a manufacturing method of gear steel for cold forging machining. The method comprises the steps that a preformed blank is obtained; and the preformed blank is subjected to reduction annealing, the gear steel for cold forging machining is obtained, and the hardness of the gear steel for cold forging machining ranges from 120 HB to 160 HB. Traditional spheroidizing annealing is replaced with three-stage coupling temperature control of reduction annealing, the temperature and time parameters in the reduction annealing process are controlled, a soft-hard phase composite structure of ferrite (30%-80%) and spheroidizing pearlite (50%-95%) is obtained, the ferrite serves as a plastic phase to absorb deformation energy, spherical carbide in the spheroidizing pearlite evenly disperses stress, and therefore the spheroidizing performance of the spheroidizing pearlite is improved. The hardness is precisely controlled within the range of 120 HB-160 HB through the synergistic effect of the two, the plasticity reserve (cracking prevention) needed by cold forging forming is met, the enough initial strength is kept, and the requirement of the cold forging technology for materials can be met.

To provide a spray method that enables spray construction with high initial strength development.SOLUTION: A spray method in which, after adding and mixing a quick-setting material into base concrete containing cement, spray application is performed on an object to be constructed, comprises a step of, prior to adding the quick-setting material, adding a quick-setting aid containing gypsum (however, excluding cases where it contains alkali metal aluminate, lime, and gypsum) to the base concrete.SELECTED DRAWING: None

The invention relates to the technical field of concrete supporting beam shell formworks, and discloses a fabricated concrete supporting beam shell formwork system and a construction method.The fabricated concrete supporting beam shell formwork system comprises a prefabricated shell formwork, the prefabricated shell formwork is of a U-shaped structure, a positioning groove is formed in one end of the prefabricated shell formwork, and a positioning strip is fixed to the other end of the prefabricated shell formwork; a fixing assembly is arranged at one end of each prefabricated shell mold, a locking assembly is arranged at the other end of each prefabricated shell mold, the fixing assemblies and the locking assemblies jointly play a role in connecting every two adjacent prefabricated shell molds, and each locking assembly is composed of a sliding structure, a locking structure and an unlocking structure. The U-shaped shell mold is prefabricated in a factory and directly assembled on a construction site, multiple links are omitted, the process is simplified, the period is shortened, efficiency is improved, and in the aspects of materials and cost, the prefabricated shell mold has high initial strength and can be used as a permanent protection layer and a part of a stress structure, and in the traditional mode, the loss of a mold plate is large, and repair cost is possibly increased.

The application discloses a kind of module self-locking embedded connection assembly methods, comprising the following steps: prefabricated structure module, the structure module with hole and end plate;Install connecting mechanism, make connecting mechanism and end plate fixed;Covering connecting plate on the end plate;Place new structure module on connecting plate.By adopting the way of knob embedding, it can be easily constructed, quickly installed, cost is simple, reliable connection, and can be compatible integrated on concrete or steel structure MIC module;Through self-locking embedding, it can be easily installed, the steps are greatly simplified than bolt installation, and there is no need to wait for initial strength formation like wet post-poured connection method, and there is no time-consuming and labor-consuming step of on-site binding reinforcement, and the quality is difficult to control.

The application provides a back-embedded device and method for supporting a water-rich stratum segment, relates to the field of tunnel engineering, and aims at the problem of poor adhesion of a support member arranged between a segment and surrounding rock. Under the action of a shear member, the initial strength is improved, under the stable action of a support layer, water seepage into the shell can be evenly diffused by the fiber cotton, the expansive cement is uniformly expanded, small gaps are filled, and thus the adhesion effect of the segment and the surrounding rock is ensured, and the support strength on the segment is improved.

The invention discloses a preparation method of sulphoaluminate cement-calcium carbide slurry autoclaved aerated concrete, which comprises the following steps: (1) adding weighed fly ash, waste aerated concrete material, calcium carbide slurry, desulfurized gypsum and foam stabilizer into water, and mixing and stirring to obtain slurry A; (2) adding sulphoaluminate cement into the slurry A, and quickly stirring to obtain slurry B; (3) adding the aluminum powder paste into the slurry B, and quickly stirring to obtain slurry C; (4) pouring the slurry C into a mold, and standing in a hot chamber to obtain a green body; and (5) cutting the green body, and performing autoclaved curing to obtain the autoclaved aerated concrete. According to the invention, the fly ash-calcium carbide slurry system is enabled to be fast in setting and hardening and fast in early strength increase in a manner of adding the sulphoaluminate cement, an alkali activator does not need to be added additionally, the problem of poor primary curing strength after calcium carbide slurry replaces quick lime in an aerated concrete process is solved, and the calcium carbide slurry completely replaces the lime, so that the cost is reduced. The emission of carbon dioxide is reduced.

To provide a concrete composition capable of obtaining a hardened body relatively excellent in development of initial strength without performing steam curing under a winter environment, a method for producing the concrete composition, and a precast concrete product.SOLUTION: The concrete composition includes cement, water, fine aggregate, coarse aggregate, glycerin and an accelerator, wherein the accelerator is one or more selected from calcium chloride, sodium carbonate, sodium thiosulfate, triethanolamine, diethanolisopropanolamine, triisopropanolamine and aluminum sulfate.SELECTED DRAWING: None