45 results about "Pozzolanic reaction" patented technology

The invention discloses solid waste-based fiber reinforced sprayed concrete and a preparation method thereof, and belongs to the technical field of concrete. The sprayed concrete is prepared from the solid waste-based cementing material, the fine aggregate, the basalt fiber, the water reducing agent, the accelerator and the water, the slag, the carbide slag, the fly ash and the cement serve as the solid waste-based cementing material, part of the cement is replaced by the fly ash and the slag, the slag can make up for the deficiency of the activity of the fly ash in the early stage, the early strength is rapidly improved, and the early strength is improved. The rebound rate is reduced; the fly ash further densifies the matrix in the later period by means of continuous pozzolanic reaction, so that the durability is enhanced; the basalt fibers, the accelerator and the water reducing agent are mixed, the hydration process is optimized, and the synergistic enhancement effect of the fibers and a matrix is achieved, so that the generation of early cracks and the development of later cracks are inhibited, and finally the sprayed concrete with high strength, high toughness and low shrinkage is obtained.

The invention discloses marine concrete resistant to chlorine salt erosion and a preparation method thereof, and belongs to the technical field of building materials. The marine concrete is prepared from the following components in parts by mass: 280 to 350 parts of cementing material, 1100 to 1200 parts of aggregate, 150 to 180 parts of mixing water and 2.5 to 4.0 parts of high-efficiency water reducing agent, and the cementing material is prepared from 210 to 270 parts of ordinary Portland cement, 50 to 70 parts of superfine slag powder and 10 to 20 parts of modifier on the basis of the cementing material; on the basis of the modifier, the modifier is prepared from 30 to 45 parts of hexacalcium aluminoferrite, 25 to 35 parts of metaettringite, 20 to 35 parts of tobermorite, 3 to 6 parts of nano attapulgite and 2 to 4 parts of a nano composite material. The components can accelerate the early hydration of cement and the volcanic ash reaction process in the concrete hardening process, so that the concrete can form a compact microstructure in the curing period and cooperate with the curing effect of a hydration product on chloride ions, thereby remarkably improving the chloride ion penetration resistance of the concrete, prolonging the service life of the structure and improving the concrete quality. The method is suitable for port engineering, maritime work structures and buildings in salinized soil areas.

The invention relates to the technical field of reinforced concrete, in particular to a preparation technology of a reinforced concrete telegraph pole, the performance of the concrete telegraph pole is improved through a multi-scale fiber synergistic toughening method, when the telegraph pole bears a bending load, steel fibers firstly play a role to restrain large cracks, and when micro cracks appear, the steel fibers play a role to restrain the large cracks. The denser composite fiber network bears stress to realize multi-stage crack resistance, which is combined with the high early strength characteristic of the sulphoaluminate cement, so that the telegraph pole has excellent impact resistance and fatigue resistance while obtaining extremely high early strength; the surface of the aggregate modified by the silicon dioxide aerogel is covered with a high-activity and high-specific-surface-area nano silicon dioxide layer, and in an alkali-rich and calcium-rich environment provided by sulfo-aluminate water cement hydration, the nano silicon dioxide and a cement hydration product are subjected to a violent pozzolanic reaction, so that the surface of the aggregate is modified by the sulfo-aluminate water cement; therefore, the compressive strength and the flexural tensile strength of the concrete are remarkably improved.

A method of preparing an enhanced reactivity pozzolan may include: contacting a starting pozzolan with a catalyst material to form a mixture of the starting pozzolan and the catalyst material; reacting the mixture of starting pozzolan and catalyst material during an induction period to form reaction products; and recovering the enhanced reactivity pozzolan.

A method of preparing an acid modified pozzolan may include: contacting a starting pozzolan with an acid to form a mixture of the starting pozzolan and the acid; reacting the mixture of starting pozzolan and the acid during an induction period to form reaction products; and recovering the acid modified pozzolan.

The invention belongs to the technical field of concrete, and provides ecological concrete and a preparation method thereof, the ecological concrete comprises 25-35 parts of steel slag, 10-20 parts of slag powder, 5-10 parts of desulfurized gypsum, 30-35 parts of recycled aggregate, 5-8 parts of charcoal, 1-2 parts of fiber, 1-1.5 parts of a water reducing agent, 0.5-1 part of an air entraining agent, 1-2 parts of an antifreezing agent, and 15-20 parts of water. The steel slag serving as an early strength and alkaline component of the concrete not only provides strength, but also can release calcium hydroxide in the hydration process due to the calcium oxide active component contained in the steel slag, so that an alkaline environment is provided for the system; the superfine slag powder is rich in active silicon dioxide, aluminum oxide and other components and can be subjected to a pozzolanic reaction with calcium hydroxide in an alkaline environment, so that the later strength of the ecological concrete is remarkably enhanced, and the defect that the later strength of the steel slag is slowly increased is overcome; according to the invention, volcanic ash reaction is taken as a core mechanism, and the strength and durability are improved by recycling wastes.

The invention relates to the field of high-performance anti-cracking and anti-seepage concrete, in particular to high-performance anti-cracking and anti-seepage concrete for hydraulic structures and a preparation method thereof. The high-performance anti-cracking and anti-seepage concrete for the hydraulic structure comprises the following substances in parts by weight: 25-30 parts of cement; 80 to 100 parts of coarse aggregate; 70 to 80 parts of fine aggregate; 10 to 15 parts of water; 3-5 parts of an anti-crack and anti-permeability modifier; the anti-crack and anti-permeability modifier comprises a silicon-aluminum base material, and the silicon-aluminum base material comprises fly ash, slag and metakaolin which are mixed according to the mass ratio of (4-5): (2.5-3.5): (2-3). The anti-cracking and anti-seepage performance is synergistically improved through the silicon-aluminum base material composite modifier. Compared with a single mineral admixture, the composite system can more efficiently refine the pore size distribution and reduce the permeability coefficient of the concrete; meanwhile, Ca (OH) 2 crystals are consumed through a volcanic ash reaction, interface stress concentration caused by crystal oriented growth is reduced, microcrack initiation is inhibited from the source, and crack resistance and permeability resistance are improved.

The invention discloses a performance improvement mechanism and a preparation method of a modified Aga soil material, a silane coupling agent and hydraulic lime are added into traditional Aga soil (Aga soil, water, elm bark juice and clear oil), and the modified Aga soil material is formed by combining a Tibetan ramming process. The modification principle is as follows: a silane coupling agent is dissolved in water to form a silanol solution, the silanol solution permeates into Aga soil along with ramming after being sprayed, and the hydraulic lime and the Aga soil are subjected to a pozzolanic reaction to generate a gelling product mainly comprising hydrated calcium silicate, so that the bonding and overall mechanical properties among particles of the Aga soil are improved; silanol and hydroxyl groups on the surface of the gelling product are subjected to dehydration condensation to form siloxane covalent bonds and enhance the structural stability; then, the silanol molecules are subjected to cross-linking polymerization, an organosilane polymer hydrophobic membrane is formed on the surfaces of the Aga soil and the gelling product, moisture is effectively blocked, and the water resistance and the impermeability of the Aga soil material are improved. The preparation method disclosed by the invention is simple, convenient, green and environment-friendly, can obviously improve the mechanical and durability of Aga soil, and has a good engineering application prospect.

The invention discloses a modified material for earthen archaeological site disease repair and a repair effect evaluation method thereof, and relates to the technical field of earthen archaeological site repair, the modified material comprises a silicon-calcium-based modified material based on metakaolin (A), calcium hydroxide (C) and silica fume (S) and an optimal ratio thereof, a comprehensive engineering performance test proves the feasibility of the silicon-calcium-based modified material in earthen ruins disease repair, the optimal ratio of A to C to S of the finally obtained ACS modified soil is 1: 2: 4, the added ACS modified material can generate a remarkable pozzolanic reaction with the ruins soil, and the denudation resistance and long-term durability of the original ruins soil are improved.

The invention provides high-strength light-weight thermal insulation mortar based on synergistic activation of bulk solid waste and a preparation method thereof.The preparation method comprises the steps that carbide slag, fly ash and a composite exciting agent are mixed and subjected to ball milling treatment, so that the volcanic ash reaction activity of Ca (OH) 2 in the carbide slag mixed material and the fly ash mixed material is activated, and pretreated powder is obtained; uniformly mixing the mixed material pretreatment powder with cement, cellulose ether, latex powder and glass beads to obtain a mixed material; adding water into the mixed material, and stirring to form mixed material thermal insulation mortar; through synergistic activation of the composite activator, the total mixing amount of solid waste is greater than or equal to 55%, and the mortar is free of cracking after being formed. The carbide slag, the fly ash and the composite activator are subjected to ball milling together, so that the composite activator fully activates the volcanic ash activity of the fly ash, a large amount of C-S-H gel is generated, and the multi-graded vitrified microbeads are matched, so that the mortar keeps the light condition under the dry density, still has good compressive strength and low heat conductivity coefficient, and realizes the synergy of high strength and light heat preservation.

Concrete composition system with nanosilica, RGO and industrial waste, comprising: an ordinary Portland cement (OPC) that serves as the primary binder in the mixture, with part of the OPC partially replaced by a combination of industrial waste and nanomaterials, including: Copper waste, which is contained in a proportion of 5 to 60 wt% of the cement content and serves as additional cement material from mining waste; Nanosilica, which is present in a proportion of 2 to 6 wt% of the cement and has a high pozzolanic reactivity to improve hydration and microstructural compaction; and reduced graphene oxide (rGO), which is present in trace amounts of 0.03 to 0.08% by weight of the cement and serves as a nano-reinforcing agent to improve crack resistance and tensile behavior; Granite powder, added as a filler in a proportion of 5 to 30 percent by weight of the total mixture, contributing to improved particle packing and reduced porosity; Fine and coarse aggregates in standardized proportions that form the granular structure of the concrete; Water added in a controlled water-binder ratio suitable to initiate cement hydration and maintain the workability of the fresh mix; a superplasticizer additive included in appropriate dosage to reduce water requirements and maintain fluidity without compromising mechanical performance.

The application provides an organic-geopolymer inorganic gel composite coated long-afterglow self-luminous paint and a preparation method thereof, raw materials of the paint include calcined metakaolin, a silicone-acrylate emulsion, an ethylene-vinyl acetate copolymer emulsion and a luminescent powder, and the luminescent powder is an aluminate type long-afterglow luminescent powder. The application adopts an organic-inorganic composite coating design, the calcined metakaolin geopolymer forms an amorphous silicate aluminate gel network through a pozzolanic reaction, the EVA, the silicone-acrylate emulsion and the silane coupling agent are used as the organic phase to effectively fill the internal pores of the geopolymer gel, meanwhile, the flexibility and the anti-cracking performance of the coating are improved, the consumption of natural resources is reduced, and energy saving and environmental protection are realized in the whole cycle of material preparation and application.

The invention discloses a soft soil curing material with synergistic effect of waste concrete recycled micro powder and lime and a preparation method of the soft soil curing material, and belongs to the technical field of soft soil curing. The soft soil curing agent provided by the invention comprises calcium hydroxide and waste concrete recycled micro powder in a mass ratio of 3: 7, wherein the particle size of the waste concrete recycled micro powder is less than 0.16 mm. According to the invention, unhydrated cement particles and active SiO2, Al2O3 and other components contained in the waste concrete recycled micro powder are utilized, and a pozzolanic reaction is carried out under the alkaline excitation action of calcium hydroxide, so that a hydrate (such as C-S-H gel) with gelling property is generated in the solidified soft soil. Gelling substances generated in the curing process of the calcium hydroxide and the waste concrete recycled micro powder can effectively bond soil particles in the soft soil to fill pores and consume free water in the soft soil at the same time, so that the mechanical property of the cured soil is greatly improved.

The invention belongs to the technical field of shield under-pressure bin opening, and particularly provides a composite clay mixed solution and application thereof, and the composite clay mixed solution is prepared from bentonite slurry, methyl cellulose and slaked lime; the bentonite slurry is obtained by mixing a bentonite solution and a sodium silicate solution, and the bentonite solution is obtained by mixing water and sodium bentonite. According to the composite clay mixed solution provided by the invention, methyl cellulose and slaked lime are introduced to synergistically enhance a system; specifically, methyl cellulose (MC) is used as a non-ionic thickening agent, and methoxyl (-OCH3) on a molecular chain of the methyl cellulose (MC) improves the consistency of a system through hydrogen-bond interaction. MC with the viscosity of 4000 mPa.s is selected in an experiment, and the addition amount of the MC is 0.3%-0.5% of the mass of the bentonite; the slaked lime and SiO2 in the bentonite are subjected to a pozzolanic reaction, and the shear strength of the system can be increased to 2.8 kPa within 6 h through the reaction.

The invention belongs to the technical field of ultra-high performance concrete, and discloses a high-activity composite mineral admixture and application in UHPC, the admixture is prepared from 700-900 parts of S95 mineral powder, 50-100 parts of fly ash, 100-200 parts of steel slag powder, 5-10 parts of quartz powder, 3-5 parts of desulfurized gypsum, 1-3 parts of a grinding aid and 1-5 parts of a microencapsulated polycarboxylic acid water reducer; the spherical glassy particles in the admixture realize microscopic filling, unsaturated Si-O bonds and hydroxyl groups promote secondary pozzolanic reaction to generate a composite colloid, and the multistage particle size gradient design and the slow-release polycarboxylic acid water reducer synergistically optimize rheology; after part of traditional silica fume is replaced by the admixture, the workability and mechanical property of UHPC can be remarkably improved, resource utilization of industrial waste residues is facilitated, and the admixture has high performance, is green and environment-friendly and has process feasibility.

The invention discloses a copper smelting slag recleaning tailing road material and a preparation method thereof. The material comprises the following components: 2.5-3.5% of ordinary Portland cement; 8-12% of modified copper smelting slag recleaning tailings; the modified copper smelting slag recleaning tailings are obtained through mechanical activation and chemical excitation treatment; 70%-75% of graded broken stone (4.75 mm to 19 mm); sand (the fineness modulus is 2.6 to 2.8): 10 to 15 percent; 0.8%-1.2% of a composite additive; and the optimal water content is 6-8%. According to the method, the modified copper smelting slag recleaning tailings are subjected to mechanical activation, potential gelling activity of the tailings can be fully released, then chemical excitation is carried out, added aluminum sulfate can react with active ingredients in the tailings in an alkaline environment to generate substances such as aluminate with gelling property, the volcanic ash reaction efficiency is remarkably improved, and the utilization rate of the copper smelting slag recleaning tailings is increased. The binding capacity of the tailings and other raw materials is greatly enhanced, the overall performance of the road material is improved, resource utilization of a large amount of tailings is achieved, and the environmental burden is relieved.

The invention discloses a cement-loaded multi-scale silicon source composite anti-seepage grouting material and a preparation method thereof, and belongs to the field of geotechnical engineering anti-seepage grouting materials. The grouting material is prepared from ordinary Portland cement, micron-scale rice hull ash, nano-scale nano silicon dioxide and sodium bentonite. The rice hull ash reacts with the volcanic ash through physical filling to optimize micron-sized pores; nano-scale pores are filled with nano-silicon dioxide, cement hydration is accelerated, and the nano-silicon dioxide and the nano-silicon dioxide synergistically optimize the pore structure and promote densification of C-S-H gel. The sodium bentonite can retain water, thicken and improve the stability of the slurry. The cross-scale synergistic effect of the multi-scale silicon sources constructs a multi-level compact filling structure from nanometer to micrometer and a multi-level hydration reaction enhancing system in the grouting material, the compactness and anti-seepage performance of the material are remarkably improved, and the grouting material is suitable for engineering fields such as water conservancy dams, tunnels, deep mines, landfills and the like with extremely high anti-seepage performance requirements.

The present invention discloses a method for preparing high-strength unfired ceramsite using phosphogypsum and coal gangue. The preparation method of the present invention comprises: drying, grinding, and screening phosphogypsum cementitious material powder and coal gangue, and then uniformly mixing them, adding distilled water while stirring until a sticky mud mass is formed to obtain a mixture containing a ball core; transferring the mixture into a ball-forming device, adjusting and preparing the amount of water for ball-forming, and screening after ball-forming to obtain wet raw material balls; aging and drying the wet raw material balls in sequence to obtain dry raw material balls, and evenly laying the dry raw material balls and naturally curing them to obtain a formed ceramsite product. The present invention creates an alkaline hydration environment by adding phosphogypsum-based all-solid waste cementitious material and coal gangue to promote the volcanic ash reaction of mineral powder, silicon-rich material and coal gangue to generate gel substances such as hydrated calcium silicate, thereby forming a denser structure, promoting the growth of ceramsite strength, and obtaining unfired ceramics with good performance.

The invention discloses a method for electric heating curing of a steel fiber-containing ultra-high performance concrete test piece, and relates to ultra-high performance concrete.The method comprises the steps that an electrode is installed in the steel fiber-containing ultra-high performance concrete test piece, and the electrifying voltage is set according to the age of the steel fiber-containing ultra-high performance concrete test piece; and electrifying an electrode mounted on the steel fiber-containing ultra-high performance concrete test piece with alternating current according to the electrifying voltage until a set target time period is reached. Alternating current is applied to the test piece within 1-24 hours after pouring, and the internal temperature of the test piece is raised to the target temperature and maintained by electrifying for 3 hours, so that cement hydration and silica fume pozzolanic reaction are efficiently promoted, rapid densification of a microstructure is realized, and early strength development is remarkably accelerated; the core problems of power-on lag, high polarization risk, process parameter stiffness, dependence on factory precuring and the like of the existing method are solved.

The invention mainly relates to the technical field of building materials, in particular to a rapid repairing material and a preparation method thereof. The concrete is prepared from the following components in parts by weight: 5-10 parts of a cementing material, 30-40 parts of Portland cement, 2-5 parts of a mineral admixture, 40-50 parts of standard sand, 0.2-0.3 part of a polycarboxylate superplasticizer, 0.2-0.3 part of a defoaming agent, 0.2-0.3 part of an early strength agent, 0.1-0.2 part of a retarder and 12-16 parts of water. According to the technical scheme, the microstructure is optimized by means of micro aggregate filling and secondary pozzolanic reaction of industrial solid waste, durability is improved, meanwhile, cement is replaced, carbon emission and material cost are reduced, and collaborative optimization of performance, environmental protection and cost is achieved.

The invention provides a superfine basalt composite admixture, and belongs to the technical field of building materials. The composite material is prepared from superfine basalt powder, active silicon powder and active calcium carbonate according to the mass ratio of (55-65): (25-35): 10. The particle size of the superfine basalt powder is smaller than or equal to 45 microns, and the specific surface area is larger than or equal to 400 m < 2 > / kg; the particle size of the active silicon powder is less than or equal to 0.3 mu m; wherein the content of amorphous SiO2 is greater than or equal to 93%. According to the composite admixture composed of the superfine basalt powder, the active silicon powder and the active calcium carbonate, through a triple synergistic mechanism of physical filling, pozzolanic reaction and crystal nucleus effect, the mechanical strength (the breaking strength is improved by 43.99%, and the compressive strength is improved by 15.85%) and the durability (the chloride ion diffusion coefficient is reduced by 1-2 orders of magnitude) of the concrete are remarkably improved. Meanwhile, by utilizing the characteristics of industrial solid waste, the cement consumption can be reduced by 30-50%, the CO2 emission can be reduced by more than 200kg / m < 3 >, and remarkable environmental protection benefits are achieved.

The application discloses a kind of based on whole solid waste carbon reduction utilization's goaf stable filling system and filling method, the system includes biological preparation culture system, solid waste prefabrication system, gas injection system and goaf, the biological preparation culture system includes two incubators, and solid waste prefabrication system includes two prefabricators.Acid bacillus, arthrobacter are respectively added into two incubators and are respectively entered into two prefabricators after cultivation, steel slag is added into the prefabricator of acid bacillus bacterial solution, calcium carbide slag, granulated blast furnace slag are added into the prefabricator of arthrobacter bacterial solution, obtain two kinds of solid waste-biological bacterial solution mixture injection mineral resources goaf, pass in carbon dioxide-air mixed gas reaction, complete the stable filling of goaf.The present application is glued into the filling body with certain strength by microorganism carbon fixation mineralization reaction and solid waste pozzolanic reaction, not only effectively utilizes greenhouse gas carbon dioxide and industrial waste, but also realizes the safe treatment of mineral resources goaf.

The application discloses a cement-based anticorrosion and antifreezing material and a preparation method thereof, and belongs to the technical field of building materials. The cement-based anticorrosion and antifreezing material comprises the following components in parts by weight: 250-350 parts of cement, 80-150 parts of modified fly ash, 50-100 parts of mineral powder, 20-40 parts of silica fume, 10-25 parts of glue powder, 3-8 parts of water reducing agent, 10-30 parts of acrylic emulsion, 1-3 parts of hydroxypropyl methyl cellulose ether, 2-5 parts of fumed silica and 400-500 parts of fine aggregate. The modified fly ash is used in combination with various auxiliary cementitious materials such as the mineral powder and the silica fume, thereby forming an efficient pozzolanic reaction system. Meanwhile, polymers such as the acrylic emulsion and the glue powder are introduced, a flexible network is constructed in the inorganic hard skeleton, rigidity and flexibility are achieved in combination, and auxiliary agents such as the efficient water reducing agent and the cellulose ether are used, so that the material not only has good anticorrosion and antifreezing performance after hardening, but also has excellent workability, water retention and adhesion in the construction process, and is suitable for various construction process requirements, and has good engineering application value.

The present application relates to the technical field of building materials, and particularly relates to an organic-inorganic composite ternary microsphere capable of realizing self-riveting in a cement matrix, and a preparation and application thereof, the microsphere comprising: a microcapsule body with a repairing agent as a core and a semi-interpenetrating network hydrogel material as a shell; the shell surface is inlaid with a pozzolanic material, and the pozzolanic material is used for pozzolanic reaction with the cement matrix to realize riveting of the two. The preparation method comprises the following steps: pre-mixing the pozzolanic material and water to obtain a suspension; adding semi-interpenetrating network hydrogel prepolymers into the suspension to obtain a first mixture; mixing the first mixture, the repairing agent and an emulsifier to obtain a second mixture; and crosslinking and solidifying the second mixture by using a sharp hole-coagulation bath method to form the microsphere. The microsphere of the present application can successfully construct a self-riveting structure with the cement matrix, and solves the problems of poor interface bonding and low self-repairing efficiency caused by the water-absorbing microcapsule as the shell of the hydrogel.

A method of preparing an enhanced reactivity pozzolan may include: contacting a starting pozzolan with a catalyst material to form a mixture of the starting pozzolan and the catalyst material; reacting the mixture of starting pozzolan and catalyst material during an induction period to form reaction products; and recovering the enhanced reactivity pozzolan.

A carbon-sequestering concrete composition and method of production are disclosed. The composition comprises geopolymer binder components, aggregates, and alginate beads formed from brown algae powder through ionic gelation. The alginate beads significantly increase CO2 absorption surface area compared to algae powder, creating a matrix across the concrete surface that enhances long-term sequestration and improves durability. The beads interact synergistically with other concrete components, including geopolymers, fly ash, and ground granulated blast furnace slag, to enhance pozzolanic reactions and create additional sites for carbon dioxide capture. The alginate beads also facilitate the dissolution of minerals like olivine, further enhancing carbon capture. The composition demonstrates superior carbon sequestration capabilities, enabling sustained CO2 absorption throughout its service life. The method includes forming alginate beads, incorporating them into the concrete mixture, and allowing for initial hardening and drying processes that promote carbon dioxide absorption directly from the air.

The invention discloses application of silica fume in a ceramic tile adhesive. The mixing amount of the silica fume is 5-10% of the total mass of a cementing material. Through filling and pozzolanic reaction, the ceramic tile glue and the interface on the back surface of the ceramic tile are firmly combined, and hollowing and falling are effectively avoided. The tile adhesive has extremely low water absorption and excellent anti-permeability, and the dense structure blocks the permeation of water, so that the tile adhesive has excellent waterproof and anti-permeability performances. The method is crucial to wet areas such as toilets and swimming pools, and can also effectively resist freeze-thaw damage. Excellent durability and chemical stability are achieved, reduction of the Ca (OH) content means that corrosion by media such as acid and salt is not prone to occurring, the carbonization resistance is higher, and the service life is longer. Shrinkage is reduced, cracking resistance is achieved, the denser structure and reduced free water can reduce drying shrinkage, and the cracking risk is reduced.

The application provides a basalt powder and a basalt fiber reinforced anti-cracking mortar and a preparation method thereof, and belongs to the technical field of cement, concrete and other building materials. The application comprises components of Portland cement, basalt powder, graded sand, basalt fiber, latex powder, cellulose ether and water reducing agent. The application optimizes the compactness of the matrix by filling and reacting with the basalt powder and the pozzolanic ash, and forms a three-dimensional reinforcing network with strong interfacial bonding by using the basalt fiber which is subjected to surface etching and silane coupling treatment. The two components synergistically improve the crack resistance and toughness of the mortar, and the mortar shows a high ductility failure mode with multiple crackings. Meanwhile, the tensile strength, the bending strength and the compressive strength of the mortar are comprehensively enhanced, and the fracture energy is significantly improved. In addition, the high-density matrix and the corrosion-resistant fiber together endow the mortar with excellent impermeability, freeze-thaw resistance and corrosion resistance, and greatly prolong the service life.

The weathering resistance of concrete bricks is enhanced by using glass powder in a concrete composition. The glass powder can reduce the cement content and also produce a pozzolanic reaction, converting free calcium ions in calcium hydroxide into calcium silicate, thereby fixing the calcium ions within the concrete. The composition includes 20 to 25 weight percent (wt.%) of a cement binder material comprising ordinary Portland cement, fly ash, calcium sulfoaluminate cement, and ground granulated blast furnace slag; 10 to 15 weight percent (wt.%) of coarse aggregate; and 32 to 39 weight percent (wt.%) of fine aggregate. The composition further includes 17 to 23 weight percent (wt.%) of glass powder, with a diameter of less than about 75 microns. The water content is 6 to 9 weight percent (wt.%). The resulting paving brick has a dry density of 1800-2200 kg / m 3 .

The embodiment of the invention provides a lightweight aggregate with a multi-layer core-shell structure and a preparation method thereof, the lightweight aggregate with the multi-layer core-shell structure comprises: an inner core, the preparation raw materials of the inner core comprise water-storage lightweight particles and a functional ion solution; the inner shell covers the inner core, and the preparation raw materials of the inner shell comprise cement, a volcanic ash material, solid waste, lime, a water reducing agent and water; the inner shell is coated with the outer shell, and preparation raw materials of the outer shell comprise cement, a volcanic ash material, a water reducing agent, nanofibers and water. According to the lightweight aggregate with the multi-layer core-shell structure and the preparation method of the lightweight aggregate, through internal curing of the inner core, pozzolanic reaction in the inner shell and the toughening effect of the nanofibers in the outer shell, the mechanical property of the lightweight aggregate with the multi-layer core-shell structure is improved, and the filling and bridging effects of the nanofibers are fully exerted; the mechanical property of an interface transition area is improved, and the lightweight aggregate with the multi-layer core-shell structure, which is low in density, high in strength and high in elastic modulus, is obtained.