254 results about "Cement based composites" patented technology

The invention provides an ultrahigh-ductility cement-based composite material for ocean engineering and a preparation method of the ultrahigh-ductility cement-based composite material for ocean engineering. The concrete is prepared from the following raw materials in parts by weight: 250 to 500 parts of cement clinker, 400 to 600 parts of fly ash, 200 to 300 parts of mineral powder, 100 to 150 parts of silica fume, 160 to 240 parts of metakaolin, 600 to 900 parts of quartz sand, 10 to 20 parts of organic synthetic fiber, 20 to 30 parts of organic corrosion inhibitor, 180 to 240 parts of water and 1 to 8 parts of water reducing agent. The organic corrosion inhibitor provided by the invention can be combined with chloride ions to form a passive film, so that the corrosion of reinforcing steel bars and the invasion of the chloride ions into concrete are inhibited, and the durability of the concrete is improved; by regulating and controlling the mixing ratio of the four mineral admixtures and the mixing amount of the synthetic fiber component, the concrete can well consider high strength, high ductility, high durability, high flow state and excellent deformation resistance. The ultrahigh-ductility concrete for ocean engineering, which can meet the toughness requirements of high compression resistance, fracture resistance and impact resistance and the requirements of high chloride ion permeation resistance and steel bar corrosion resistance, can be obtained.

The invention relates to a building material, and particularly discloses a high-ductility cement-based composite material and a preparation method thereof.The cement-based composite material is prepared from, by weight, cement, water, an additive, PE fibers, modified PVA fibers, sand, hollow glass beads, silica fume, calcium silicate and expanded perlite; wherein the modified PVA fiber is prepared by compounding and modifying polyimide aerogel with acrylate resin and epoxy resin; the preparation method comprises the following steps: mixing the cement, the silica fume, the sand, the calcium silicate and the expanded perlite, and then adding the PE fibers to prepare a dry-mixed mixture; and mixing an additive with water to obtain a mixture, then adding the modified PVA fibers, uniformly stirring, then adding the dry-stirred mixture, and uniformly stirring to obtain the high-ductility cement-based composite material. According to the present invention, the fly ash is not added, such that the product quality stability is ensured, the good mechanical property and the good ductility are provided, and the energy saving and thermal insulation functions are provided.

The invention belongs to the technical field of cement-based materials, and particularly relates to a self-sensing engineering cement-based composite material and a preparation method and application thereof. The self-sensing engineering cement-based composite material provided by the invention comprises an engineering cement-based composite material and a conductive carbon material, the engineering cement-based composite material is prepared from the following raw materials: a cementing material, aggregate, organic fibers, a water reducing agent, a dispersing agent and water, the cementing material comprises cement, mineral powder, silica fume and limestone powder; the conductive carbon material comprises one or more of carbon black, carbon nanotubes and graphene. The conductive carbon material can form a conductive network in the self-sensing engineering cement-based composite material, so that the conductivity is improved, a self-sensing function is given to the self-sensing engineering cement-based composite material, the relationship between stress or strain and the resistivity change rate is established, and real-time monitoring of stress and strain of building materials and structures can be realized without an external sensor.

The invention provides a high-ductility cement-based composite material freeze-thaw damage prediction method and system fused with surface multi-scale structure recognition. The method comprises the following steps: S1, obtaining ECC surface damage information after a freeze-thaw cycle effect; s2, constructing an optimized ECC freeze-thaw damage strength prediction model based on a machine learning method; s3, according to the parameters obtained in the step S1, the surface damage coefficient of the ECC is determined through the prediction model in the step S2; and S4, predicting the damage strength of the ECC after freezing and thawing according to the surface damage coefficient. The invention provides an ECC freeze-thaw damage prediction model based on surface recognition, and the damage strength of a material can be speculated by analyzing surface damage picture information. According to the model, image information such as fiber exposure and surface peeling is directly associated with damage strength by using an image feature extraction and machine learning algorithm, and efficient and accurate prediction of the performance of the ECC material after freeze-thaw damage is realized.

The invention relates to an ionic redox couple thermoelectric cement-based composite material, the composite material comprises a cement matrix and redox couples, and the redox couples exist in pores of the cement matrix; wherein the redox pairs are K4 [Fe (CN) 6] and K3 [Fe (CN) 6], and the porosity of the cement matrix is 25%-50%. According to the invention, the migration of ions in a cement matrix is regulated and controlled by introducing the redox couple, so that a relatively high Seebeck coefficient, conductivity and power factor are achieved while good mechanical properties are maintained, and the thermoelectric conversion efficiency is remarkably improved. Besides, the composite material can drive electrode reaction through temperature difference to generate a closed current loop, stable current output is achieved, and the problem of current output of a traditional ionic thermoelectric material is solved.

The invention relates to the field of cement-based composite materials, and particularly discloses a high-performance self-compacting high-crack-resistance fiber-reinforced cement-based composite material and a preparation method thereof.The cement-based composite material is prepared from cement, fly ash microspheres, silica fume, a modified geopolymer, sand, fine stone, polypropylene fibers, an expanding agent, an additive and water; wherein the additive at least comprises welan gum; the preparation method comprises the following steps: mixing and stirring the cement, the fly ash beads, the silica fume, the sand, the fine stone and the modified geopolymer, and adding the expanding agent to prepare a primary mixture; and mixing the admixture with water, adding the primary mixture, then adding the polypropylene fiber, stirring and mixing, then adding the rest admixture, and stirring to obtain the product. The cement-based composite material has the characteristics that the prepared cement-based composite material has better fluidity and better segregation resistance and crack resistance, and the cement-based composite material can be applied to the fields of non-dismantling bottom die floor support plate bottom plates, foundation support grouting reinforcement, section increasing method reinforcement, quick pavement repair and the like.

The invention relates to a marine environment mass concrete construction and crack repairing method, which comprises the following steps: in a mass concrete construction stage, carrying out aggregate precooling, carrying out layered intermittent pouring by using the precooled aggregate, and carrying out cooling treatment at the same time, so that the internal and external temperature difference is controlled within 20 DEG C; if cracks appear on the mass concrete, a polymer modified cement-based composite material is prepared for repairing, the polymer modified cement-based composite material comprises composite gel, a macromolecular tackifier and aggregate, the composite gel is based on 60%-70% of Portland cement, and 5%-8% of nano silicon powder and 10%-15% of fly ash are doped; the macromolecular adhesive comprises 0.5%-1.2% of polyacrylamide or 2%-3% of epoxy resin emulsion. When the scheme is used for repairing marine mass buildings, the overall viscosity of concrete can be improved, the internal and external temperature difference of the concrete is reduced, and the overall impermeability of the concrete repairing material is improved.

The invention relates to the technical field of building materials, and provides a high-durability modified cement-based composite material and a preparation method thereof.The high-durability modified cement-based composite material comprises a carbon dot polymer, mixing water and Portland cement, and the specific preparation steps are as follows: adding citric acid and urea into water to be dissolved, and then putting into a high-pressure reaction kettle to be heated to obtain an initial product; adding the initial product into water, and carrying out centrifugation, filtration, rotary evaporation and drying to obtain the carbon dots; the preparation method comprises the following steps: dissolving carbon dots in water, preparing an initial carbon dot polymer product by adopting a hydrothermal method or a microwave method, adding the initial carbon dot polymer product into water, centrifuging, filtering, rotationally evaporating and drying to obtain a carbon dot polymer; and mixing the carbon dot polymer with mixing water and Portland cement to obtain the high-durability modified cement-based composite material. The modified cement-based composite material prepared by the invention is simple to prepare, low in cost, green and low-carbon; the rust can be efficiently inhibited, and concrete reinforcements are effectively protected from being corroded; the method can be widely applied to reinforced concrete and has wide application prospects.

The invention relates to the technical field of building materials, in particular to a phase change energy storage type cement-based composite material PCM-UHPC, which comprises an ultra-high performance cement-based material (UHPC) matrix and a microencapsulated phase change energy storage material (PCM microcapsule), a microcapsule wall material of the microencapsulated phase change energy storage material (PCM microcapsule) is compounded by a polymer and a nano inorganic material, and the polymer and the nano inorganic material are compounded to form the phase change energy storage type cement-based composite material PCM-UHPC. Wherein the ultra-high performance cement-based material (UHPC) matrix is composed of Portland cement, silica fume, fly ash, quartz powder, quartz sand and a water reducing agent. The material has the energy storage and heat preservation performance and the ultrahigh mechanical property, temperature regulation and energy balance can be achieved in the environment with large temperature difference changes, heating and refrigerating energy consumption of buildings is reduced, and the material has high thermal stability and long service life and is suitable for engineering structures such as building energy saving and temperature control bridges and tunnels.

The invention relates to a photovoltaic heat dissipation enhanced radiation refrigeration cement-based composite material as well as a preparation method and application thereof. The composite material comprises white Portland cement, radiation refrigeration particles and water, the radiation refrigeration particles comprise alpha aluminum oxide and barium sulfate, the mass fraction of the radiation refrigeration particles relative to the total solid content in the composite material is 30%-60%, and the mass ratio of the alpha aluminum oxide to the barium sulfate is 1: 1-2: 1; the average particle size of the radiation refrigeration particles is 0.3-10 [mu] m; the mass fraction of the white Portland cement relative to the total solid content in the composite material is 40-70%. Compared with the prior art, the reflectivity and emissivity of the material are improved, efficient photovoltaic thermal management is achieved, meanwhile, the material has the advantages of being low in cost, simple in process, high in stability and the like, development of the building photovoltaic integrated technology is expected to be promoted, and the energy utilization efficiency is improved.

The invention belongs to the technical field of building materials, and provides a cement-based composite material with an organic-inorganic interpenetrating structure and a preparation method of the cement-based composite material. According to the preparation method disclosed by the invention, the monomer and the polymer containing the active group are introduced, the in-situ polymer formed by the monomer through in-situ polymerization and the polymer containing the active group form a double-network polymer, a single-network structure is refined, and the single-network structure and a cement hydration reaction product which is synchronously performed form an organic-inorganic interpenetrating structure; the interaction between double networks and the cement-based material is enhanced, meanwhile, the microstructure is optimized, the mechanical property of the single polymer modified cement-based material can be improved, the compressive strength is improved, and the breaking strength is further enhanced; the prepared cement-based composite material with the organic-inorganic interpenetrating structure has excellent breaking strength and compressive strength.

The invention discloses a design method of a high-ductility cement-based composite material, which comprises the following steps: S1, carrying out mix proportion design by using Box-Behnken in a response surface method, and designing a three-factor three-response test, the three factors being a water-binder ratio, a sand-binder ratio and a fiber mixing amount; s2, mixing and proportioning the materials according to the three factors in S1, and preparing to obtain the high-ductility cement-based composite material, s3, maintaining the high-ductility cement-based composite material obtained in the S2, and testing the three-response mechanical properties in the S1, wherein the three responses are compressive strength Y1, breaking strength Y2 and equivalent bending toughness Y3; and S4, analyzing the influence of the interaction of the three factors in the S1 on the three responses in the S3, establishing a response surface model equation through variance analysis verification, and verifying and optimizing a result to obtain an optimal mix proportion. A Box-Behnke method in RSM is adopted to establish a regression model with the water-binder ratio, the sand-binder ratio and the fiber mixing amount as influence factors and the compressive strength, the breaking strength and the equivalent bending toughness as response values.

The invention discloses an interface enhanced composite shear wall based on a high-ductility cement-based material. The high-ductility cement-based composite materials are formed in edge constraint areas on the two sides of the shear wall, and the common concrete is formed in a core area in the middle of the shear wall. The interface separation net is a high-strength ribbed non-dismantling formwork net and is vertically arranged at the junction of the edge constraint area and the core area, the section of the interface separation net is in a periodic concave-convex wave shape or a stepped shape, and a macroscopic mechanical meshing interface is formed. The interface seaming ribs are U-shaped ribs and are horizontally arranged at the positions of the inter-rib slurry penetrating nets of the interface separation net in a penetrating mode, one ends of the interface seaming ribs are anchored to the edge constraint area common steel bars, and the other ends of the interface seaming ribs extend into the core area and are connected with longitudinal and transverse rib cross joints of the composite material grid ribs in a hooked mode; the problems of rigidity mutation and slippage of the heterogeneous material interface are solved by utilizing the geometric occlusion effect of the interface separation net and the anchoring effect of the deep bolt pins and joints of the interface sewing ribs, cooperative work of a high-ductility material and common concrete is achieved, and good anti-seismic performance is achieved.

The invention relates to a high-strength and high-ductility cement-based composite material as well as a preparation method and application thereof. The high-strength and high-ductility cement-based composite material comprises the following components in parts by weight: 60-90 parts of cement, 10-40 parts of industrial solid waste, 20-40 parts of fine aggregate, 1-2 parts of a water reducing agent, 1-10 parts of fibers and 14-22 parts of water, the industrial solid waste comprises one or more of fly ash, silica fume, slag, steel slag and red mud; the fibers comprise one or more of polyethylene fibers, polyvinyl alcohol fibers, steel fibers, polypropylene fibers, carbon fibers, glass fibers, basalt fibers and the like; the tensile strain of the cement-based composite material is not less than 8%. Compared with the prior art, the cement-based composite material prepared by the invention has relatively high compressive strength and relatively strong deformability, and can effectively solve the problems of high brittleness, easiness in cracking, low impermeability and the like of cement concrete in a tunnel engineering lining structure.

The present invention relates to the technical field of cement-based building materials, and in particular to a high-performance cement-based composite material for repair and reinforcement engineering and a preparation method thereof. The present invention, on the one hand, starts from a glue system to solve the problems of low mechanical strength and slow hardening time of cement-based composite materials; on the other hand, starts from a fiber system, selects a method of modifying a variety of fibers to make the fibers easier and more uniformly dispersed in mortar, ensuring that the slurry can have relatively good working performance, and optimizes admixtures to prepare a high-ductility concrete with large fluidity, fast hardening and high strength, so that it can meet the needs of rail transit and road rapid repair and reinforcement engineering.

The invention discloses a preparation method of a cement-based artificial lawn blanket, and belongs to the technical field of greening engineering. According to the preparation method, the cement-based artificial lawn blanket comprises three-dimensional mesh cloth, simulated green plants, a cement-based composite material and a packaging layer; the simulated green plant comprises a green leaf part and a grass root part; the preparation method comprises the following steps: S01, preparing the three-dimensional mesh cloth; s02, preparing simulated green plants from low-density polyethylene flame retardant resin, and arranging the simulated green plants in the three-dimensional mesh cloth; s03, pouring a cement-based composite material into the three-dimensional mesh cloth; s04, spraying a packaging layer on the bottom of the three-dimensional mesh cloth; wherein in the step S02, linear low-density polyethylene is used as a matrix for preparing the low-density polyethylene flame retardant resin, and the low-density polyethylene flame retardant resin comprises a composite flame-retardant material composed of an electrodeless flame-retardant material and an organic flame-retardant material. According to the cement-based artificial lawn carpet obtained through the preparation method of the cement-based artificial lawn carpet, simulated green plants are good in flame retardance, and the outdoor color is stable.

The invention discloses a microcapsule phase change cement material, which is prepared by compounding a microcapsule with phase change performance and a cement matrix, the microcapsule is of a core-shell structure, the raw materials of the shell are melamine, urea and formaldehyde, the raw material of the core material is octadecane, and Tween 80 and lauryl sodium sulfate are used as emulsifiers. The preparation method comprises the following steps: 1, preparing an MUF resin prepolymer; 2, preparing a core material O / W emulsion; 3, polymerization reaction of the microcapsules; and 4, preparing the microcapsule phase change cement material. When the composite material is used as a cement-based composite material, the melting temperature ranges from 25 DEG C to 29 DEG C, the crystallization temperature ranges from 19 DEG C to 23 DEG C, the melting enthalpy ranges from 13.47 J / g to 29.78 J / g when the mixing amount is 10%-30%, the crystallization enthalpy ranges from 12.94 J / g to 28.41 J / g, and the coating efficiency is 67.5%. The initial decomposition temperature ranges from 386.13 DEG C to 390.96 DEG C, the finishing temperature ranges from 399.49 DEG C to 406.42 DEG C, and the maximum degradation temperature ranges from 438.78 DEG C to 443.64 DEG C; the heat conductivity coefficient is 0.3216 to 0.3949, and is improved by 39.4 percent compared with that of standard cement.

The invention discloses a lightweight heat-insulation cement-based composite material, and relates to the technical field of cement-based composite materials, the lightweight heat-insulation cement-based composite material comprises the following material components by weight: 40-60 parts of a cement matrix, 20-35 parts of a lightweight aggregate, 5-12 parts of a polymer modifier, and 0.5-0.3 part of a functional additive, the cement matrix is sulphoaluminate cement or Portland cement, and the functional additive is a water-based composite material. The lightweight aggregate comprises hollow glass beads with the particle size of 0.1-0.5 mm, expanded perlite with the particle size of 0.5-2 mm and surface modified aerogel particles, the aerogel particles are silicon dioxide aerogel or silicon carbide aerogel, the surface area of the aerogel particles is 700-600 m / g, the pore diameter of the aerogel particles is 40-50 nm, the polymer modifier is acrylate-styrene copolymer emulsion, and the particle size of the polymer modifier is 1-10 m / g. The solid content of the acrylate-styrene copolymer emulsion is 50-45%, the glass transition temperature of the acrylate-styrene copolymer emulsion is-10 DEG C to 15 DEG C, and the functional additive comprises a cellulose ether thickener, a polycarboxylate superplasticizer and a nano aluminum oxide dispersion liquid.

The invention provides a cement-based composite material based on a bionic structure and a preparation method thereof, and belongs to the field of building materials.The cement-based composite material comprises a plurality of cement slurry layers and a plurality of non-metal continuous fiber layers which are alternately stacked layer by layer; steel fibers are mixed in the cement slurry layers, and the steel fibers in the same cement slurry layer are arranged in the same direction; the non-metal continuous fibers in each non-metal continuous fiber layer are arranged in the same direction; and the projection included angle theta between the steel fibers in any cement slurry layer and the nonmetal continuous fibers in the adjacent nonmetal continuous fiber layer meets the following condition: 5 degrees is greater than or equal to theta. A discontinuous fiber stacking structure is improved, a rigid discontinuous steel fiber and flexible non-metal continuous fiber alternate stacking structure is adopted, and a bionic structure is formed through precise pouring forming, so that the cement-based composite material has ultrahigh tensile strength and strain performance.

The invention discloses a high-elastic-modulus and high-ductility cement-based composite material for assembly type component joint connection and a preparation method thereof.According to the scheme, the composite material is prepared from, by mass, 500-700 parts of cement, 360-504 parts of granulated blast furnace slag, 120-168 parts of fly ash, 120-168 parts of silica fume, 323-462 parts of quartz sand and 377-539 parts of iron ore sand. The concrete is prepared from the following components in parts by weight: 176 to 246 parts of water, 14 to 18 parts of composite fiber, 5.5 to 7.5 parts of a water reducing agent, 30 to 42 parts of an expanding agent, 5 to 7 parts of a binder, 0.5 to 0.7 part of a retarder, 1 to 1.4 parts of a deflocculating agent, 0.15 to 0.21 part of a defoaming agent and 0.5 to 0.7 part of a rheological agent. Furthermore, a corresponding step-by-step stirring preparation process is matched, so that the accurate regulation and control of the material performance are effectively realized. According to the invention, the problems of poor working performance, low tensile strength, insufficient elastic modulus and the like of the traditional high-ductility concrete (ECC) in assembly type component node connection can be solved, and the strict requirements of assembly type nodes on strength, construction and deformation performance can be met.

The invention discloses a microorganism-nano synergistically reinforced cement-based composite material for self-repairing concrete cracks, which realizes the self-repairing and performance improvement of the cracks through the synergistic effect of bacillus pseudofirmus, carbon nanotubes, nano magnesium oxide and red mud. The material has the following characteristics: bacillus pseudofirmus is used as a microbial remediation agent, and dormant spores are activated when meeting water and oxygen and then are subjected to a series of biochemical reactions to induce calcium carbonate precipitation products so as to effectively fill microcracks; the carbon nano tube network structure not only enhances the mechanical property of the concrete, but also can provide a channel for directional deposition of a repairing substance; the nano magnesium oxide compensates shrinkage stress through hydration reaction, and meanwhile, a proper alkaline environment is maintained to guarantee microbial activity; the industrial waste red mud is used for replacing part of cement, so that carbon emission is reduced, and microorganisms are fixed by utilizing the porous characteristic of the red mud.

The invention discloses a high-strength and high-conductivity cement-based composite material and a preparation method thereof. The cement-based composite material is characterized by being prepared from the following raw materials in parts by weight: 300 to 550 parts of calcium aluminate cement powder, 600 to 1600 parts of silica sand, 45 to 160 parts of oyster shell particles, 45 to 160 parts of iron-based amorphous alloy powder, 5 to 15 parts of conductive basalt fiber and 120 to 80 parts of water. Wherein the combined action of the oyster shell particles and the iron-based amorphous alloy inhibits the alkali efflorescence phenomenon of the cement-based composite material, and the synergistic action of the iron-based amorphous alloy and the conductive basalt fiber greatly improves the electrical and thermal conductivity of the cement-based composite material; the silica sand, the oyster shell particles and the iron-based amorphous alloy particles are used as the continuous grading fine aggregate to synergistically improve the compactness and compressive strength of the cement-based composite material, and the prepared cement-based composite material is good in thermal conductivity and electrical conductivity, high in strength and free of the alkali efflorescence phenomenon.

The invention discloses a lightweight high-strength high-toughness cement-based composite material and a preparation method thereof. The composite material is prepared from the following components in parts by mass: 1000 parts of a cementing material, 200-400 parts of fine aggregate, 150-250 parts of water, 10-30 parts of a water reducing agent, 14-23 parts of synthetic fiber and 10-30 parts of silicon dioxide aerogel. The preparation method comprises the following steps: mixing and stirring 1000 parts of the cementing material, 200-400 parts of the fine aggregate and 10-30 parts of the silicon dioxide aerogel to obtain a dry material, then adding 10-30 parts of the water reducing agent and 150-250 parts of the water into the dry material, mixing and stirring to obtain neat paste, and finally adding 14-23 parts of the synthetic fiber into the neat paste while stirring, and mixing and stirring to obtain slurry. The light-weight, high-strength and high-toughness cement-based composite material is few in component variety, simple in preparation method, low in volume weight, high in strength and large in ultimate tensile strain, and the problems that a traditional light-weight and high-toughness cement-based material is large in light-weight aggregate mixing amount, low in strength, poor in ductility and stability and the like are solved; and the method has a wide application prospect in infrastructures such as high-rise building structure facades and large-span bridge structure pavement layers.

The invention discloses an artificial biological reef for naturally repairing coral, a system and a preparation method. The artificial biological reef body comprises a main body structure made of a cement-based composite material, and at least one hollow cavity is formed in the main body structure; the ecological through holes penetrate through the wall thickness of the main body structure and are used for promoting water flow exchange and marine organism channels; the biological affinity surface layer is arranged on the surface of the main body structure, is made of cement-based materials mixed with seaweed extracts and has rough textures so as to promote attachment of coral larvae; and a reinforcing framework formed by a corrosion-resistant fiber reinforced material embedded in the main body structure improves the overall structural strength and impact resistance. The system comprises a plurality of reefs, special connecting pieces and a foundation stabilizing platform, and can be combined into an array for simulating a natural reef space structure. The preparation method comprises the steps of seaweed extract preparation, bioactive slurry preparation, assembly prefabrication, integrated pouring forming, maintenance and function integration, and preparation of the eco-friendly, stable-structure and multifunctional artificial reef is achieved.

The invention provides a high-strength and high-ductility damage self-repairing cement-based composite material based on spiral memory alloy fibers and a preparation method of the high-strength and high-ductility damage self-repairing cement-based composite material, and belongs to the technical field of underwater engineering concrete structures. According to the invention, the matrix mix proportion of the cement-based composite material and the hybrid reinforcement effect of the three fibers on the matrix are redesigned, so that the tensile strain capacity is also remarkably improved while the strength of the UHPSC is improved, and the deformation ductility and the cumulative energy dissipation capacity of the cement-based composite material are further remarkably enhanced; as the spiral superelastic SMA fibers have self-resetting capacity, restoring force can be provided for the unloaded cement-based composite material, tensile cracks of the cement-based composite material are promoted to be automatically closed or the width of residual cracks of the cement-based composite material is obviously reduced, and on the basis, the self-healing capacity of an incompletely hydrated cementing material in the cement-based composite material is matched, so that the self-healing performance of the cement-based composite material is improved. And the UHPSC material can present a good damage self-repairing effect.

The invention discloses low-carbon concrete using steel slag as aggregate and a cementing material and a preparation method of the low-carbon concrete, and relates to the fields of cement-based composite materials, solid waste resource utilization and low-carbon green development. The cement-based composite material is prepared from 400 to 700 parts of steel slag particles, 300 to 600 parts of steel slag micro powder, 120 to 240 parts of an exciting agent, 4 to 10 parts of a water reducing agent, 70 to 200 parts of CO2 gas and 100 to 250 parts of water. The preparation method comprises the following steps: mixing the steel slag particles, the steel slag micro powder and the exciting agent, adding part of water, introducing CO2 gas, stirring, adding the rest water and the water reducing agent, and stirring. The mixing amount of the steel slag in the concrete is increased, the activity of the steel slag is enhanced through carbonization treatment, the use of cement and gravel aggregate is reduced, carbon emission is reduced, the carbonization depth, early strength and porosity of the concrete are improved, and remarkable environmental protection benefits and practical application value are achieved.

The present invention provides a high-ductility cement-based composite material, which comprises, by weight, 20-30 parts of Portland cement, 25-45 parts of fly ash, 10-20 parts of mineral powder, 1-2 parts of PP fiber, 0.5-1 part of a polycarboxylic acid high-performance water reducer, 1-10 parts of 40-70 mesh quartz sand, 5-10 parts of 70-100 mesh quartz sand, 0.1-0.5 parts of polyacrylamide, and 15-20 parts of water. The modified PP fiber is PP fiber modified by nano-calcium carbonate, nano-silicon dioxide, and a coupling agent. The preparation method comprises the following steps: respectively weighing Portland cement, fly ash, mineral powder, quartz sand, and polyacrylamide, dry-mixing them in proportion to obtain a dry mix; then adding the polycarboxylic acid high-performance water reducer and water to the dry mix in at least two portions and stirring them; and finally adding the modified PP fiber and continuing to stir to obtain the cement-based composite material. The cement-based composite material has excellent mechanical properties, can improve the strength and durability of the structure, and has high ductility and high strength.

The invention relates to a nanofiber cement-based composite material suitable for 3D printing. The nanofiber cement-based composite material comprises the following raw materials in parts by weight: 45-50 parts of cement, 8-12 parts of silica fume, 6-10 parts of fly ash, 5-8 parts of sand, 3-5 parts of PVA, 3-5 parts of a polycarboxylate superplasticizer, 3-5 parts of floating beads and 30-35 parts of water. According to the cement-based composite material disclosed by the invention, the cement, the silica fume, the fly ash and other raw materials are matched with the modifier doped with the crystal whiskers and the effect supplement based on nano SiO modification, and the prepared cement-based composite material has excellent mechanical properties and coordinated improvement of fluidity through blending, coordination and common synergism of the raw materials.

The application provides a cement-based composite material and a preparation method thereof, and belongs to the technical field of composite material preparation.The application comprises the following steps: step one, preparing heat-conducting and enhanced phase change energy storage microcapsules with uniform and controllable particle sizes; step two, preparing heat-conducting and enhanced phase change energy storage microcapsules with controllable wall thicknesses; and step three, preparing a phase change energy storage cement-based composite material test piece.The application prepares heat-conducting and enhanced phase change energy storage microcapsules with uniform and controllable particle sizes through a microfluidic chip, controls the wall thicknesses of the microcapsules through a layer-by-layer self-assembly method, and finally adds the heat-conducting and enhanced phase change energy storage microcapsules with controllable wall thicknesses into a cement paste, so that the microcapsules are dispersed in the cement paste, and a phase change energy storage cement-based composite material with good heat regulation capacity is prepared.

This invention relates to the field of cement technology, specifically to a fiber-reinforced high-strength cement pole and its preparation method. The pole comprises a steel wire skeleton and a conical annular pole body covering its outer circumference. The pole body is formed by centrifugal molding and curing of a cement-based composite material containing interfacially pre-complexed basalt chopped fibers. The interfacially pre-complexed basalt chopped fibers are obtained sequentially through alkaline activation, silane-nano silica treatment, polycarboxylate segment grafting, and calcium ion pre-complexation, and are added to the slurry after the cementitious material is initially moistened and before the aggregate is added. This method improves the dispersibility and interfacial bonding stability of the basalt chopped fibers in a low water-cement ratio cement matrix, thereby enhancing the pole's compressive, tensile, crack, shrinkage, and freeze-thaw resistance.