12 results about "Initial strength" patented technology

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.

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 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 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.

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.

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 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 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.