148 results about "Shrinkage cracking" patented technology

The invention discloses an anti-cracking reverse design method for early-age concrete. Comprising the following steps: acquiring material performance parameters; constructing a chemical-thermal-force-phase field damage model of the early-age concrete; constructing a constitutive relationship between early-age behaviors and stress-strain of the concrete; carrying out shrinkage cracking simulation calculation on the early-age concrete, and quantitatively evaluating the damage cracking risk of the early-age concrete by using a damage development index Idd. And performing crack resistance optimization design on the early-age performance of the concrete by using an orthogonal design method to obtain a crack resistance optimization result in the performance combination and development process of the concrete. According to the method, the damage development index peak value is taken as a control target, the shrinkage cracking risk of the early-age concrete structure under different material properties, development processes, constraints and curing temperatures can be quantitatively evaluated, the optimal design of the concrete mix proportion is guided, a large amount of test exploration is avoided, the manpower and material resource cost is reduced, and the method is suitable for large-scale popularization and application. The method has important significance on early crack control of a concrete structure and has remarkable progress.

The invention provides solid-waste-based fluid-state solidified soil and a preparation method of the solid-waste-based fluid-state solidified soil. The solid waste-based flow state solidified soil comprises a filling material, a framework material and a reinforcing material, the filling material comprises the following components in parts by weight: 60-95 parts of engineering residue soil, 5-40 parts of alkaline waste residues, 5-30 parts of a cementing material, 1-10 parts of a polymer emulsion, 0.5-3 parts of silica fume, 0.1-1 part of cellulose ether, 0.1-1 part of a compound water reducing agent and 0.5-2 parts of an exciting agent. The framework material comprises waste concrete blocks and / or waste brick blocks; the reinforcing material comprises a waste safety net and / or fiber gridding cloth. The flow-state solidified soil can achieve rapid backfilling in a narrow space, is excellent in shrinkage cracking resistance and impermeability, simple in preparation method and convenient to apply and construct, effectively solves the problems that the flow-state solidified soil is large in shrinkage, prone to cracking and the like, improves the quality of a backfilling project, achieves in-situ resource utilization of construction waste, and reduces the construction cost. And the construction cost of engineering can be reduced, and the problems of land occupation, environment pollution and the like caused by solid waste stacking are reduced.

The invention provides a capillary crystalline waterproof agent, a preparation method and application, and the capillary crystalline waterproof agent comprises the following raw materials in parts by weight: 80-100 parts of a non-cement-based cementing material, 15-25 parts of an alkali activator, 1.5-2.5 parts of a thickener, 12.5-22.5 parts of a flexibilizer, 0.1-0.3 part of a dispersant and 5-10 parts of a water reducer, the flexibilizer is formed by mixing carboxyl-terminated liquid rubber modified epoxy resin and inorganic ceramic particles according to the mass ratio of 7: (3-5), and the dispersing agent is alkylphenol polyoxyethylene ether. Under the action of the dispersing agent, the toughening agent can be uniformly dispersed in the concrete, so that the overall toughness of the concrete is improved. The improvement of the overall toughness not only can bear deformation or shrinkage cracking of the concrete caused by evaporation of moisture, temperature difference and external stress, but also can better resist cracking from the source, reduce cracks and pores, prevent moisture from permeating and improve the impermeability of the concrete; and the bending resistance of the concrete after complete water permeability and self-healing can also be improved.

The invention discloses modified slag fiber reinforced cement mortar and a preparation method thereof. According to the invention, the modified slag fiber is adopted as a reinforcement body, and the method has the advantages of reasonable utilization of solid wastes, low energy consumption, low cost, environmental protection, high mechanical properties of a mortar test piece, small shrinkage cracking and the like. The nano silica sol is adopted to modify the slag fibers, so that the durability of the slag fibers in a cement material can be better improved, hydration products on the surfaces of the fibers can be distributed more uniformly and densely, and an interface transition area between the fibers and a matrix material is reinforced, so that the strength of the mortar is remarkably improved; the used slag fiber is a fibrous material prepared by taking blast furnace slag and fly ash as raw materials through a blowing or centrifugal thread throwing process, so that the solid waste utilization rate can be increased, and environmental governance and protection are facilitated. According to the implementation of the invention, on one hand, the practical application of the slag fiber in the cement matrix material is explored; on the other hand, solid waste utilization can be promoted.

The invention discloses a special fluidizing agent for covering C70 concrete outside an arch ring as well as a preparation method and application of the special fluidizing agent. The fluidizing agent is formed by compounding nano silicon wafers, superfine limestone powder, floating beads and superfine talcum powder, all the components have a synergistic effect, and the flowability of the concrete is improved through different mechanisms. The nanometer silicon wafer provides high specific surface area and active surface groups, lubrication among particles is promoted through electric coupling and ion excitation effects, internal friction resistance of the concrete is reduced, and the later strength of the concrete is improved through a volcanic ash reaction after hardening. The superfine limestone powder releases free water by destroying a flocculation structure, and plays a filling role. The floating beads serve as micron-sized spherical particles, and friction force among the particles is reduced. The superfine talcum powder has a sheet structure, and plays a role in dispersing and lubricating the cementing material. The fluidizing agent can be applied to large-flow-state and high-crack-resistance C70 concrete wrapped outside an arch ring, the problems that high-strength concrete is insufficient in fluidity and high in shrinkage cracking risk are effectively solved, and the construction performance and the engineering quality are improved.

The invention discloses an all-solid-waste cementing material stabilized macadam base mixture which is prepared from the following raw materials in parts by weight: 4-6 parts of an all-solid-waste cementing material, 0-6 parts of wet-discharged fly ash, 0-20 parts of silicon-manganese slag, 10-20 parts of steel slag, 52-65 parts of macadam and 4-6 parts of water. The moisture content of the wet discharged fly ash is 8-12%. According to the all-solid waste cementing material stabilized macadam base mixture provided by the invention, the characteristics of low heat, micro-expansion and relatively high water demand of the all-solid waste cementing material can be utilized, agglomeration of wet-discharged fly ash is reduced, and the uniformity of the water stabilized base mixture is improved, so that the hydration heat is reduced, the risk of quick setting and shrinkage cracking is reduced, meanwhile, the solid waste utilization rate is increased, and the production cost is reduced. And the production cost and the carbon emission are reduced.

The slope slide-resistant pile comprises a slope protection assembly, the slope protection assembly is composed of anchor rods, a slope body, reinforcing ribs, a reinforcing mesh, a transverse #-shaped frame and a vertical #-shaped frame, and the anchor rods are symmetrically and fixedly connected to the slope body; according to the slope protection device, a good stabilizing effect is provided for a slope body through the slope protection assembly, the structure is simple, and the construction efficiency is improved; the drainage assembly is prepared in advance, the installation groove is dug, rapid installation and use can be achieved, a good drainage function is provided, auxiliary drainage can be conducted through a redundant channel after the filter screen is blocked, and the use stability of the equipment is improved; by adding the accelerator into the concrete and curing for a specified long time, the concrete setting can be obviously accelerated, the early strength can be improved, the normal increase of the strength can be ensured to a certain extent, the shrinkage cracking can be reduced and prevented, and meanwhile, the stability of the slope surface is further improved by a method and a spraying process of spraying the concrete twice, so that the slope surface quality is improved. And slope landslide is effectively avoided.

According to the low-temperature high-durability magnesium phosphate cement and the preparation method thereof, dead burned magnesia powder serves as a core gelling base material and can provide a large amount of active Mg < 2 + >, ammonium dihydrogen phosphate can provide an acid environment and PO4 < 3->, the dead burned magnesia powder and the ammonium dihydrogen phosphate are subjected to an acid-base neutralization reaction in the presence of water to generate ammonium magnesium phosphate hydration products, and the magnesium phosphate hydration products are subjected to a low-temperature high-durability magnesium phosphate cement. The products are interwoven to form a hardened body framework, and a strength foundation is laid for cement; borax is adopted as a key retarder, borate ions generated after the borax is dissolved in water can be adsorbed on the surfaces of dead burned magnesia powder particles, a magnesium borate complex film is formed, the dissolution of Mg < 2 + > and the reaction of PO4 < 3-> are hindered, the cement setting time is effectively delayed, and the construction requirements are met; and the borax can also refine the crystal structure of a hydration product, reduce the porosity, improve the impermeability and the volume stability of a hardened body, and avoid shrinkage cracking.

The invention belongs to the technical field of high-speed railway ballastless track construction, and particularly discloses an anti-crack functional material for ballastless track roadbed slab concrete and a preparation method of the anti-crack functional material. The anti-cracking functional material provides a whole-course expansion effect and delays early expansion by means of a mode of coating calcium oxide with calcium carbonate and compounding magnesium oxide; the protein modified starch is used as a hydration heat regulation and control layer, so that the regulation and control effect of single starch on cement hydration heat is improved, and a compound expanding agent is slowly released; carbonized and expanded rice husks are used as a biomass water-absorbing and anti-releasing material, so that the self-shrinkage and drying shrinkage of the concrete are reduced; the temperature-sensitive microgel material is used as the outermost layer component, the highest temperature value of the roadbed slab concrete is reduced, the temperature drop shrinkage stress of the concrete is improved, and the temperature shrinkage cracking risk of the roadbed slab concrete is inhibited. Various shrinkage stresses of the roadbed slab are accurately regulated and controlled, the limiting and restraining stress of the prefabricated sleeper and the base on the concrete of the roadbed slab is effectively compensated and improved, and the anti-cracking performance of the concrete of the ballastless track roadbed slab is fundamentally improved.

According to the low-shrinkage 3D printing zirconia ceramic and the preparation process thereof, photosensitive polyimide is selected, the photosensitive polyimide has an imine ring and a photosensitive group on a macromolecular chain and has the advantages of excellent photosensitivity, thermal stability, low volume shrinkage and the like, a photoinitiator does not need to be added into a product system, and the preparation process is simple. Curing can be directly completed under ultraviolet irradiation, and the problems of ceramic shrinkage, cracking and the like caused by volatilization or decomposition of a photoinitiator in a workpiece during degreasing are avoided; the ratio of the dispersing agent to the plasticizer in the product system is optimized, the viscosity of the slurry is reduced, the solid content is increased, the shrinkage rate after sintering is reduced, and the flowability and the printing precision of the slurry are ensured. Besides, by combining a flash sintering treatment process, grain growth coarsening is inhibited, a nanoscale compact structure is realized, and internal defects are reduced, so that the zirconia ceramic prepared by the method has the advantages of no defect, compact structure, smaller grain size (smaller than 1 mu m), excellent fracture toughness and higher relative density.

The present invention provides a multi-scale toughening and shrinkage-compensating C80 high-crack-resistant self-compacting concrete and a preparation method thereof. The present invention uses low-shrinkage and crack-resistant composite cement to compensate for the shrinkage of C80 concrete, avoiding the disadvantage that general expansive agents are difficult to function due to the low water-cement ratio design of ordinary C80 concrete, and solving the problem that C80 concrete is prone to shrinkage and cracking. The present invention uses multi-scale hybrid fibers to strengthen toughness and crack resistance, and uses high-strength fine steel fibers, multi-anchor steel fibers, and temperature-shrinkage-induced organic fibers to improve the toughness of C80 concrete and its crack resistance in the heating / cooling stages on a macro scale; and uses CaCO3 and CaSO4 composite whiskers and nano-silica-modified water-based polyurethane to form a uniform three-dimensional toughening network inside the cementitious slurry, thereby improving the tensile strength and toughness of C80 concrete on a micron scale. This allows C80 concrete to have the characteristics of low shrinkage, high toughness, and high crack resistance.

The invention relates to the technical field of building materials, and discloses low-temperature anti-cracking mass concrete and a preparation method thereof.The low-temperature anti-cracking mass concrete is prepared from, by weight, 50%-70% of low-heat Portland cement or low-heat Portland slag cement, 0.5%-1.5% of a retarder, 0.8%-2% of an expanding agent, 0.8%-2% of a water reducing agent, 0.1%-0.5% of reinforced fibers, 20%-40% of a mineral admixture and 3%-5% of an anti-freezing agent. And the balance of aggregate and water. By selecting low-heat Portland cement or low-heat slag Portland cement, the hydration heat is reduced; the fluidity, the strength and the durability are improved by utilizing the water reducing agent; and the freeze-thaw cycle resistance is improved by adding the antifreeze agent. The rising speed of the internal temperature of the concrete is reduced, the strength and durability are improved, and long-term stable performance in cold regions is ensured. The problem that mass concrete is prone to early shrinkage cracking in a low-temperature environment is solved.

The method comprises the following steps: preparing an aluminum oxide nanowire precursor with a certain length-diameter ratio by a hydrothermal method, mixing the aluminum oxide nanowire precursor with silicon dioxide nano powder and ceramic fibers, filling the mixture into a honeycomb, and carrying out compression molding, curing, ethanol solvent replacement, subcritical drying and other process steps to obtain the honeycomb filled aerogel thermal insulation material. The honeycomb filled aerogel heat insulation material is successfully prepared. According to the preparation method disclosed by the invention, efficient preparation of the aerogel-filled honeycomb material with controllable filling density and excellent mechanical strength is realized by regulating and controlling a micro-nano hierarchical structure and mixed components. The aerogel is combined with the honeycomb, and the aluminum oxide nanowire cluster and the ceramic fiber are introduced as inorganic components, so that the shrinkage cracking of the aerogel at high temperature is inhibited, and the structural stability and the mechanical property of the material at high temperature are remarkably improved.

The invention discloses a concrete internal and external synergistic curing material, a preparation method and a curing method. The internal curing material comprises the following components in parts by weight: 5-20 parts of microbial flora, 20-50 parts of a carbon source, 5-50 parts of a calcium source, 5-20 parts of a nitrogen source and 1-10 parts of inorganic salt. The external curing material comprises the following components in parts by weight: 10-30 parts of water-soluble polyvinyl alcohol, 5-15 parts of a cross-linking agent, 5-30 parts of a phase change material, 5-20 parts of a barrier material, 10-30 parts of a water retention material and 50-300 parts of water. The internal curing material is doped inside the concrete, and the external curing material is impregnated or sprayed outside the concrete, so that the internal curing material and the external curing material have a synergistic effect on the concrete, and the concrete has the advantages of obvious curing effect, good compressive strength, permeability resistance, temperature control performance and water retention performance, avoidance of shrinkage cracking caused by humidity or temperature difference, and good comprehensive performance. And the mechanical and durability of the concrete are enhanced.

This invention provides a highly protective cement safe resistant to drilling impact, comprising an outer shell, an inner liner within the outer shell, a filling cavity formed between the outer shell and the inner liner, a concrete protective layer within the filling cavity, and a sealing cap on the top of the outer shell. The concrete protective layer, used in the safe, comprises the following components: 4200-4800 parts of hydraulic cementitious material, 1600-2200 parts of pozzolanic mineral admixture, 450-650 parts of active mineral admixture, 450-650 parts of fine inert filler, 4200-5200 parts of graded high-hardness fine aggregate, 850-900 parts of water, 70-85 parts of high-efficiency water-reducing agent, 12-20 parts of defoamer, and 1100-1300 parts of end-hooked steel fiber. The components of this invention work synergistically to effectively improve the bonding performance between concrete and the steel plate matrix, inhibit shrinkage and cracking during curing, and enhance product lifespan and structural stability.

The invention discloses a soil shrinkage cracking analysis method and device based on near-field dynamics. The analysis method comprises the following steps: establishing near-field dynamic models of a soil body, wherein the near-field dynamic models comprise a heat conduction model, a moisture diffusion model and a motion model; setting initial parameters and boundary conditions of the model; solving the heat conduction model and the moisture diffusion model through an explicit algorithm, solving the motion model through an implicit algorithm, and obtaining a displacement field variable value under the current time step; and based on the variable value, updating a scalar value function to obtain local damage and strain energy density, and obtaining a stress field variable value under the current time step through a near-field dynamics differential operator. According to the method, complex behaviors of the soil body under the heat-water-force coupling effect are considered, the explicit-implicit hybrid algorithm is adopted, and the dry shrinkage cracking process of the soil body can be accurately simulated.

The invention relates to the technical field of cement-based material preparation, and particularly discloses a process for modifying blast furnace slag aggregate and an early-strength low-shrinkage cement stabilized macadam mixture. The process comprises the following steps: (1) quenching slag particles discharged from a smelting furnace to room temperature to obtain pretreated slag particles; and (2) reheating the pretreated slag particles for temperature return treatment, then quickly cooling to a set temperature, and then slowly cooling to room temperature to obtain the modified blast furnace slag aggregate. The cement stabilized macadam mixture comprises ordinary Portland cement, sulphoaluminate cement, modified blast furnace slag aggregate, granulated blast furnace slag powder, fluorgypsum powder, carbide slag powder, river sand, a water reducing agent, fibers, nano MgO and mixing water. According to the invention, not only are the strength, hardness and stability of the blast furnace slag improved, but also the problem of mechanical property degradation caused by internal shrinkage and cracking of the cement stabilized macadam mixture is effectively relieved.

The invention relates to construction waste recycled aggregate concrete and a preparation method thereof, relates to the technical field of concrete, and improves the workability and durability of the concrete by reasonably proportioning a modified water reducing agent with other raw materials. Wherein the modified water reducing agent is prepared by carrying out primary esterification on maleated rosin and a monomer containing hydroxyl, then carrying out dicarboxylation on the modified water reducing agent and sulfonating the modified water reducing agent through sulfite, has a hydrophobic skeleton and carboxyl and sulfonic acid double hydrophilic groups, and can strongly adsorb cement particles, form a static electricity and steric hindrance double effect, disperse a cement binding material and release water; and workability loss and shrinkage cracking caused by high water absorption of the recycled aggregate are inhibited. The concrete prepared by the invention has the advantages of good water reducing property, good strength and difficulty in collapsing.

A solid waste-based nano-hydrated calcium silicate nucleating agent, its preparation method, and its application in low-heat cement are disclosed. This invention belongs to the field of building materials technology. By weight, it comprises the following components: 10-30 parts of carbide slag, 20-45 parts of yellow phosphorus slag, and 400-2000 parts of sodium hydroxide solution. The calcium hydroxide content in the carbide slag is ≥80%. The silicon dioxide content in the yellow phosphorus slag is ≥35%, and the calcium oxide content is ≥40%. The pH value of the sodium hydroxide solution is 11-12. This invention uses carbide slag, yellow phosphorus slag, and sodium hydroxide solution as raw materials to synthesize a solid waste-based nano-hydrated calcium silicate nucleating agent. Utilizing its nano-sized hydrated calcium silicate as a seed crystal in the early stage of hydration in low-heat cement, it can provide nucleation sites for the hydrated calcium silicate gel, a product of low-heat cement hydration, reducing the nucleation barrier of the hydrated calcium silicate gel, promoting the hydration rate and early strength development of low-heat cement, and providing strong support for the later strength development of low-heat cement, effectively improving the problem of drying shrinkage cracking in low-heat cement.

The application discloses low-shrinkage light-weight high-strength alkali-activated foam concrete and a preparation method and application thereof. The raw material composition of the foam concrete comprises 30-80 parts by weight of slag powder, 40-120 parts by weight of mineral admixture, 2-15 parts by weight of porous filler, 5-20 parts by weight of sodium-potassium water glass, 0.5-10 parts by weight of foaming agent and 0.5-5 parts by weight of anti-shrinkage agent. The anti-shrinkage agent is prepared by the following method: placing water-absorbing resin in a saturated shrinkage reducing agent solution, keeping under heating conditions, making the water-absorbing resin reach a saturated water state, and then separating the water-absorbing resin and draining the liquid to obtain the anti-shrinkage agent. The application not only reduces the self-shrinkage degree of the alkali-activated foam concrete, overcomes the shrinkage and cracking problem of the foam concrete during service, but also increases the compressive strength of the alkali-activated foam concrete.

The invention discloses a series green and environment-friendly mortar formula suitable for northwest climate, and particularly relates to the technical field of mortar, the series green and environment-friendly mortar formula comprises the following components: 100-250 parts of cement, 20-30 parts of attapulgite powder, 20-30 parts of boric sludge, 150-250 parts of natural sand, 10-20 parts of reinforcement powder, 5-10 parts of polysiloxane elastomer, and 2-4 parts of itaconic acid. The prepared mortar is better in breaking strength, corrosion resistance and water resistance, meanwhile, the mortar can be toughened and enhanced, the shrinkage resistance of the mortar is improved, early-stage shrinkage cracking is reduced, then the prepared mortar can effectively slow down the evaporation speed of water, the wettability of the mortar is kept, and the water resistance of the mortar is improved. The mortar prepared by the invention has better weather resistance, can resist strong sunlight, high temperature, low temperature and other extreme weather conditions in northwest regions, keeps the long-term stability and durability of the mortar, and can prevent the mortar from being frozen and damaged under the severe cold weather condition in winter in northwest regions.

This invention belongs to the field of industrial solid waste resource utilization technology, and relates to a circulating fluidized bed ash-based cementitious material for road base courses and its preparation method. The raw materials for the road base course cementitious material are composed of the following mass parts: 29-43 parts of circulating fluidized bed ash, 16-27 parts of ground blast furnace slag, 3-6 parts of silica fume, 7-15 parts of P.O42.5 silicate cement, 0.1-0.4 parts of activator, and 27-30 parts of water. The circulating fluidized bed ash is prepared by mixing circulating fluidized bed fly ash and slag in a mass ratio of (2-5):(5-10). This invention effectively alleviates the problems of fast setting time and shrinkage cracking of traditional road base course cementitious materials by utilizing the characteristics of micro-expansion and long hydration time of circulating fluidized bed ash. The advantage of this invention is that it promotes the large-scale utilization of circulating fluidized bed ash and contributes to carbon emission reduction in the road sector.

The present invention discloses a rapid soil salinity measurement method, belonging to the field of soil measurement. The invention involves extracting the fractal dimension characteristics of cracks on the surface of viscous salinized soil using digital image processing. By establishing a mathematical quantitative relationship model between the fractal dimension and soil salinity, crack characteristic parameters extracted from photos of soil surface shrinkage cracking obtained through a standardized field process are incorporated into the prediction model, ultimately achieving rapid, efficient, and non-destructive online measurement of the salt content of cracked salinized soil. The present invention has the advantages of a simple measurement process, low cost, low loss, low cost, strong stability, and real-time and quasi-real-time performance.

The invention relates to the technical field of solid waste material recycling, in particular to a solid waste-based geopolymer and a preparation method thereof. The solid waste-based geopolymer comprises the following components in parts by mass: 400-500 parts of fly ash; 400 to 500 parts of mineral powder; 40-60 parts of a sodium hydroxide aqueous solution; 200 to 400 parts of water; the solid content of the nano waterborne epoxy emulsion is 30-62%, the particle size of the nano waterborne epoxy emulsion is 100-900 nm, and the nano waterborne epoxy emulsion accounts for 3-9% of the total mass. According to the invention, the compactness of a matrix is enhanced, shrinkage cracking caused by water evaporation is reduced, the toughness and anti-permeability of the material are improved, the compactness of an interface is enhanced, the saltpetering condition of the matrix is inhibited, and wide application in the field of building materials is facilitated.

The invention discloses a roller compacted concrete composition adaptive to a high altitude environment and a preparation method thereof, and the roller compacted concrete composition comprises the following components in parts by mass: 60-100 parts of cement, 65-75 parts of fine aggregate, 100-120 parts of coarse aggregate, 10-20 parts of zeolite powder, 1-5 parts of dopamine hydrochloride, 5-15 parts of activated fiber, 0.2-0.4 part of aminated polystyrene microspheres, and 0.1-0.5 part of a carbodiimide cross-linking agent. And 1-2 parts of a water reducing agent. The problems of insufficient early strength, later shrinkage cracking and poor freezing resistance of concrete in a high-altitude environment are solved, a composite system of polydopamine modified zeolite and activated fibers optimizes pore distribution and a stress transfer path, the balance of early strength, crack resistance and durability is realized, and the early strength, crack resistance and durability of the concrete are improved. And a reliable concrete solution is provided for high-cold and high-altitude engineering.

The utility model discloses a seam filling and leveling anti-cracking structure for a window frame with a large rabbet and a window frame structure, and relates to the field of doors and windows. The seam filling and leveling anti-cracking structure for the window frame with the large rabbet comprises a concrete wall body with a hole and the window frame connected to the inner wall of the hole, the concrete wall body protrudes to form an inner side wall pier, and a seam with an L-shaped cross section is defined by the end face and the side face of the window frame, the concrete wall body and the inner side wall pier; the gap is filled with a light cement-based mortar leveling layer, and a waterproof layer and an outer sealing layer which extend to the side face of the window frame are sequentially arranged at the end, away from the inner side wall pier, of the light cement-based mortar leveling layer. The seam filling and leveling anti-cracking structure for the window frame with the large rabbet and the window frame structure have the advantages of being convenient to construct, high in construction efficiency and low in construction cost, and shrinkage, cracking and leakage of the seam filling position of the window frame can be avoided.

The invention discloses a curing method for inhibiting drying shrinkage cracking of cured sludge, and belongs to the technical field of crack prevention of cured sludge in geotechnical engineering. The artificial fine aggregate for inhibiting the cured sludge from drying shrinkage cracking is prepared from the following raw materials in parts by mass: 60 to 70 parts of gypsum powder, 20 to 30 parts of blast furnace slag, 2 to 10 parts of calcium carbide dust, 4 to 8 parts of cement and 0.5 to 1 part of sodium dodecyl benzene sulfonate. After the artificial fine aggregate disclosed by the invention is mixed into sludge, not only can the grading of the sludge be improved, but also the curing hydration reaction can be promoted to be continuously carried out by adsorbing free water through the porous structure, so that the dry shrinkage deformation of the cured sludge is compensated, and the dry shrinkage cracking resistance and the anti-seepage performance of the cured sludge can be improved. According to the invention, the artificial fine aggregate is prepared from a large mixing amount of industrial waste residue, and is mixed into the sludge to be cured, and the dry shrinkage deformation of the cured sludge is inhibited through grading improvement, free water adsorption, self volume expansibility and strength increase.

The invention discloses high-water-retention and anti-cracking all-solid waste sludge-based foam light-weight fluid-state soil and a preparation method thereof, and belongs to the technical field of solid waste resource utilization and civil engineering filling materials, the high-water-retention and anti-cracking all-solid waste sludge-based foam light-weight fluid-state soil comprises aggregate, an alkali-activated gelling system, a water-retention and anti-cracking agent and light-weight filler, the aggregate comprises high-water-content sludge, and the alkali-activated gelling system comprises water-retaining and anti-cracking the alkali-activated gelling system comprises fly ash, red mud, steel slag and an alkali activator, the water-retaining anti-cracking agent comprises xanthan gum, the light filler comprises foam, layered pouring is performed during construction, a foam-stabilizing anti-collapse layer is arranged between two layers of fluid-state soil, and a water-retaining anti-cracking layer is sprayed on each layer. According to the invention, the problems of large cement consumption, high carbon emission and easy dry shrinkage and cracking in the traditional foam light fluid soil are effectively solved, and the water-retaining property and the crack resistance of the material are obviously improved; meanwhile, a cement-like gel structure is formed through solid waste synergistic excitation, efficient resource utilization of the waste sludge is achieved, and the engineering cost and the environmental burden are reduced.

This invention discloses a method for improving the crack resistance of ultra-high performance concrete structures, relating to the field of concrete materials. The invention involves bonding polylactic acid (PLA) fibers and metal fibers with polyurethane adhesive to form a composite fiber. After treatment with polyurethane adhesive, the composite fiber forms a three-dimensional support network, which is alternately laid with a fine slag layer to form a gradient structure, effectively inhibiting the initiation and propagation of microcracks. The cementitious system, combined with composite admixtures, reduces the heat of hydration, and the micropores of the fine slag buffer shrinkage stress, significantly reducing shrinkage cracking. The self-healing microcapsules loaded with fine slag are uniformly dispersed, releasing a repair agent when cracks occur, rapidly healing microcracks, significantly restoring mechanical properties and impermeability, and improving durability. Furthermore, under the alkali-activated effect during the PLA fiber curing process, the fine slag can bond tightly with the composite fiber, achieving a synergistic "crack prevention-repair" effect, adapting to the construction of complex components, reducing material costs, shortening the curing cycle, and significantly reducing the total life-cycle cost.

The present application relates to the field of solidifying agent, and more particularly to a kind of composite solidifying agent for construction waste recycled material flow state solidified soil and preparation method thereof, comprising the following raw materials: sulphoaluminate cement 20-30 parts, slag powder 15-25 parts, recycled brick powder 10-15 parts, amino-terminated hyperbranched polymer 4-7 parts, silane coupling agent 2-4 parts, urease composite material 2-3 parts, urea microspheres 1-3 parts, calcium chloride 0.5-2 parts, construction waste recycled micro powder 10-18 parts, fly ash 5-10 parts.The solidifying agent solves the technical problems of weak interface in construction waste recycled material flow state solidified soil, enzyme activity easy deactivation, large strength fluctuation, serious shrinkage and cracking and the like through multi-component synergistic effect.