2094 results about "Crack resistance" patented technology

The invention relates to the technical field of anti-cracking performance testing, in particular to an ultra-high performance concrete anti-cracking performance testing system and a dynamic monitoring method thereof.The system comprises a dynamic stress field simulation feedback module used for sensing three-dimensional distribution of a micro stress field in concrete in real time by constructing a flexible loading array to obtain dynamic stress field data; the multi-scale damage evolution tracking module is used for deploying a high-resolution acoustic emission network and a distributed optical fiber sensing layer based on dynamic stress field data of the flexible loading array to form a full-scale evolution graph from microdefects to macroscopic cracks; and the intelligent healing efficiency evaluation module obtains stress redistribution data and a full-scale evolution graph, and a repairing medium containing a tracer agent is injected into a preset crack path. According to the method, the whole process of crack resistance of the material from defect initiation to repair and regeneration can be quantitatively evaluated; and finally, outputting a dynamic evolution rule of the crack resistance and enhancing potential evaluation.

The invention discloses fiber-reinforced anti-crack concrete and a preparation method thereof, and relates to the technical field of building materials, the fiber-reinforced anti-crack concrete comprises the following raw material components: 310-450 parts of cement, 150-190 parts of water, 930-1200 parts of coarse aggregate, 630-800 parts of fine aggregate, 80-180 parts of mineral active admixture, 1.2-18 parts of multi-element composite fiber, 1.8-4.5 parts of polycarboxylic acid water reducer, and 20-35 parts of anti-crack synergistic system. Through a quaternary fiber system, a three-dimensional interlocking net-shaped crack-resistant framework is formed in concrete slurry, the problems that the single fiber reinforcement effect is limited, and the interface bonding force with a concrete matrix is insufficient are solved, and the crack resistance and the mechanical property of the concrete are improved.

The invention provides a tear-resistant, wear-resistant, low-smoke and non-dripping sheath material as well as a preparation method and application thereof. The tear-resistant wear-resistant low-smoke non-dripping sheath material is prepared from the following components in parts by weight: 25 to 35 parts of metallocene linear low-density polyethylene, 10 to 15 parts of ethylene-vinyl acetate copolymer, 6 to 8 parts of compatilizer, 50 to 60 parts of aluminum hydroxide, 10 to 15 parts of magnesium hydroxide, 3 to 4 parts of microencapsulated red phosphorus, 5 to 8 parts of lithium oxide synergist, 4 to 6 parts of silicone master batch, 0.3 to 0.7 part of carbon black master batch and 1.5 to 2.5 parts of coupling agent. The tear-resistant wear-resistant low-smoke non-dripping sheath material provided by the invention has the characteristics of being halogen-free, flame-retardant, tear-resistant and wear-resistant, and a low-smoke halogen-free flame-retardant power cable prepared from the sheath material has the characteristics of high smoke light transmittance during combustion, no dripping and cracking resistance.

The invention relates to a preparation method of a geopolymer composite material based on modified fiber, which comprises the following steps: S1, fiber pretreatment: the fiber is one of basalt fiber and polyformaldehyde fiber; s2, performing surface roughening treatment on the fibers through a polyvinyl alcohol modified impregnating compound to obtain roughened fibers; s3, the roughened fibers are subjected to surface functional modification treatment through a functional modified impregnating compound, and functional modified fibers are prepared; s4, uniformly mixing the powder and an expanding agent according to a mass ratio, and adding an alkali activator solution and the functional modified fibers to prepare a geopolymer gel material; s5, the geopolymer gel material is subjected to stirring, mold filling, steam curing forming, demolding and continuous curing, and the geopolymer composite material based on the modified fiber is obtained.According to the preparation method, the geopolymer composite material with high strength and excellent crack resistance and toughness is obtained through alkali excitation, and the problems that geopolymers are low in toughness and large in brittleness are effectively solved.

The invention provides steam-cured alkali-activated fly ash concrete and a preparation method thereof. The steam-cured alkali-activated fly ash concrete is prepared from the following components in parts by mass: 30 to 40 parts of fly ash, 10 to 15 parts of slag, 10 to 20 parts of water glass, 60 to 80 parts of fine aggregate, 110 to 140 parts of coarse aggregate, 2 to 6 parts of water, 1 to 3 parts of nano SiO2 and 0.1 to 0.5 part of basalt fiber. The content of alkali in the water glass is 8.5-9.5%, and the modulus of the water glass is adjusted to 1.3-1.5 by using sodium hydroxide; the mass ratio of short fibers with the length of 6-12mm to long fibers with the length of 12-24mm in the basalt fibers is (0.5-2): 1. The alkali content, the water glass modulus and steam curing parameters are optimized, and meanwhile, nano SiO2 and basalt fibers are added for synergistic enhancement, so that the concrete has good crack resistance and compressive strength.

The present invention proposes an intermediate diaphragm-free, suspended formwork-free, and negative moment tooth block-free beam bridge, and a design method thereof. The beam bridge includes prefabricated main girders, a wet joint, lower structures, and pier cap transverse beams above the lower structures. The concrete deck slabs of adjacent prefabricated main girders are connected by the wet joint. The design method of the above beam bridge includes the following steps: S1, initial design of the main girders; S2, calculation of the non-uniform deflection of the main girders and the indirect transverse stress of the deck slabs; S3, calculation of the direct transverse stress of the deck slabs; S4, crack resistance verification of the deck slab; S5, optimization of bridge parameters to reduce the stress on the driving surface; S6, completion of the beam bridge design. The beam bridge and its design method effectively solve the problem that the existing intermediate diaphragm-free beam bridge is prone to longitudinal cracking at the joints, and realize the suspension tension without the wet joint suspended formwork of the deck slab and the negative bending moment tendon, and have better mechanical properties and better economic, environmental and social benefits, which can facilitate the promotion and application of such bridges in various types of highways , railways and municipal engineering.

The invention relates to the field of building material preparation, in particular to a high-strength concrete material and a preparation method thereof.According to the high-strength concrete material, through the synergistic effect of core-shell type temperature-sensitive resin particles, a pH response type expanding agent and industrial solid waste composite micro powder, multi-environment self-adaptive crack resistance and mechanical property breakthrough are achieved. The core component is prepared from 180 to 240 parts of cement, industrial solid waste composite micro powder (30 to 50 parts of fly ash-based nano SiO2 and 50 to 70 parts of steel slag micro powder), 10 to 15 parts of core-shell resin particles and 8 to 12 parts of pH response type expanding agent. According to the preparation process, multi-section intelligent stirring (ultra-high-speed shearing and dispersing of the nanometer material) and dynamic maintenance of the internet of things are adopted, the hydration process is precisely regulated and controlled, and the finally prepared material has excellent compressive strength and anti-cracking performance. The method is suitable for severe scenes such as ocean engineering and plateau buildings, and has wide application prospects.

The invention relates to the technical field of building materials, in particular to anti-crack mass concrete and a preparation method thereof, and the concrete is prepared from a gelling system, composite aggregate, a gradient functional additive and water according to a specific ratio. The preparation method is achieved through premixing, gradient stirring and gradient temperature control curing, the three-stage expansion effect of the compound expanding agent is utilized to be matched with the concrete shrinkage process, the hydration heat inhibitor is combined for reducing the temperature peak, basalt fiber is used for reinforcing, and the cracking risk is quantitatively evaluated, so that the 28-day restrained expansion rate of the concrete reaches 0.012% or above, the cracking risk coefficient is smaller than or equal to 0.7, and the concrete has the good crack resistance. The hydration heat peak value is reduced to 48 DEG C or below, and the cement is suitable for engineering of ultra-long structures, large-volume side walls and the like, has no harmful cracks within one year or above, has crack resistance and mechanical properties, and is wide in application prospect.

The invention provides a method for evaluating the crack resistance of tunnel body concrete, and belongs to the technical field of wind tunnels, and the method comprises the steps: uniformly arranging multiple types of sensors on the surface of a tunnel body concrete structure to form a high-density monitoring network, employing a concrete circular ring constraint test piece to establish an anti-crack reference database, and constructing a multi-working-condition temperature stress database; acquiring multi-dimensional data such as strain, temperature and acoustic emission in real time, inputting the monitoring data into a liquid adaptive neural network model to predict crack initiation probability and expansion risk, establishing a crack risk assessment function, formulating a corresponding processing strategy according to a risk coefficient range, and starting an intelligent spray maintenance system; a closed-loop control system from monitoring perception to risk early warning to active protection is formed, and the technical problem that crack initiation and expansion risks of a hole body concrete structure cannot be accurately predicted under complex working conditions is solved.

The invention belongs to the technical field of motor casing lost foam casting, and particularly relates to a special coating for a motor casing lost foam as well as a preparation method and application thereof. Through a quantitative formula design method, an aggregate proportion calculation formula based on thermal expansion coefficient matching and a grain size distribution correlation formula based on target air permeability, cooperative compounding of quartz powder and bauxite is achieved, and key functional components such as mullite, organic matter fibers and crystalline flake graphite are combined; the unification of high air permeability and excellent crack resistance of the motor shell lost foam coating is realized. The invention further provides a two-time coating gradient drying efficient process matched with the coating, and on the premise that the coating performance is guaranteed, the production efficiency is remarkably improved, and the energy consumption is reduced.

The invention discloses a concrete anti-cracking method and system based on fiber reinforcement, and belongs to the technical field of concrete anti-cracking. The method comprises the following steps: acquiring real-time strain data in concrete through a distributed optical fiber sensor; analyzing the data to obtain a three-dimensional crack propagation path containing a crack initiation position, a propagation angle and a tip position; identifying the dominant development direction of the crack and a fan-shaped potential expansion interval which extends at an expansion angle by taking the tip as a vertex based on the path data; in the potential expansion interval of the to-be-poured area, a fiber distribution layer arranged in the dominant development direction is formed through directional arrangement equipment; and the fiber-reinforced anti-cracking structure is formed through vibrating and compacting treatment. According to the invention, directional blocking of fibers to crack expansion is realized, the problem of disordered expansion of cracks is effectively solved, and the anti-cracking efficiency of concrete is improved.

The invention discloses a high-crack-resistance self-repairing sprayed concrete composition as well as a preparation method and application thereof. The composition comprises the following components in percentage by mass: 40%-50% of cement, 50%-60% of aggregate, 1%-2% of composite microfibers, 3%-5% of modified polymer emulsion, 1%-2% of an additive, 0.5%-1.5% of a nano reinforced phase and 2%-3% of a self-repairing microcapsule, and also comprises an anti-corrosion additive. The composite microfiber is a mixture of polypropylene and basalt microfiber, and the nano reinforced phase is a compound system of nano calcium carbonate and silicon dioxide. The preparation method comprises the steps of aggregate pretreatment, dry material mixing, wet material preparation, microcapsule introduction and injection molding, the aggregate is pretreated through a silane coupling agent, the cement is formed by compounding ordinary Portland cement and aluminate cement, and the modified polymer emulsion is modified through a siloxane monomer. According to the composition, through the synergistic effect of the composite microfibers, the self-repairing microcapsules and the nano reinforced phase, the crack resistance and the self-repairing capacity are improved, the composition is particularly suitable for a corrosive environment, and the service life of a structure can be prolonged.

The invention belongs to the field of metal materials, and provides a 70MPa-grade low-temperature container steel plate for hydrogen energy storage and transportation and a manufacturing method of the 70MPa-grade low-temperature container steel plate, and the steel plate comprises the following components in percentage by weight: 0.15%-0.18% of C, 0.12%-0.16% of Si, 0.74%-0.98% of Mn, less than or equal to 0.01% of P, less than or equal to 0.01% of S, 1.12%-1.44% of Ni, 0.47%-0.75% of Cr, 0.01%-0.02% of V, 0.11%-0.19% of Mo, 0.022%-0.034% of N, 0.002%-0.0028% of La and the balance of Fe and inevitable impurities. The manufacturing method comprises the steps of smelting, continuous casting, four-stage efficient slab heating, two-stage rolling, two-stage cooling and heat treatment. The steel plate produced by the method has good obdurability matching and high and low temperature service performance, and the steel plate has excellent hydrogen-induced crack resistance, sulfide stress cracking resistance and stress corrosion resistance; and the steel plate has good wear resistance, and meets the manufacturing and application requirements of the high-performance steel plate for hydrogen energy storage and transportation.

The invention provides a method for improving the high-temperature crack resistance of a cupronickel alloy based on addition of an alterant, which comprises the following steps: S1, heating a cupronickel alloy raw material until the cupronickel alloy raw material is completely molten; s2, scum in the metal solution is fished out; s3, adding a copper-magnesium alloy; s4, adding pure titanium, and fully melting and reacting the pure titanium through stirring; s5, scum in the metal solution is fished out; s6, casting after the furnace front analysis is qualified; s7, obtaining a cupronickel alloy round ingot or flat ingot; the copper-magnesium alloy is added as a deoxidizing agent, so that the oxygen content of a metal solution can be reduced, oxygen is prevented from reacting with alloy elements to generate inclusions, the purity of the alloy is improved, and the crack resistance of the alloy is enhanced; the fine and uniform grain structure can effectively improve the high-temperature plasticity of the cupronickel alloy, reduce grain boundary defects, improve the high-temperature crack resistance of the cupronickel alloy and avoid cracking under high-temperature forging or hot rolling.

The invention relates to a preparation method of high-temperature-resistant and high-performance molded concrete for a high-ground-temperature tunnel. The invention provides a preparation method of concrete adapted to a high-ground-temperature environment, aiming at the problems of difficulty in guaranteeing the workability of a mixture, easiness in cracking after setting and hardening, insufficient middle and later strength development and carbonization resistance and the like of the existing high-ground-temperature tunnel secondary lining molded concrete. The concrete is prepared from mineral admixtures such as wollastonite powder, Portland cement, fly ash and the like, organic synthetic fiber materials such as coarse aggregate, fine aggregate, polypropylene and the like, and admixtures such as a polycarboxylic acid water reducer and the like according to a specific mass ratio. The prepared concrete has excellent performances of self-compaction, early strength, high permeability resistance, crack resistance, carbonization resistance and the like in a high-ground-temperature environment, can adapt to a high-ground-temperature tunnel construction environment with the surrounding rock temperature of 28-95 DEG C, effectively solves the construction problem of high-ground-temperature tunnel secondary lining molded concrete, and has remarkable economic and social benefits.

The invention discloses a nano composite cement-based material and a preparation method, and belongs to the technical field of cement-based rapid repairing materials, the material comprises the following components by weight: 1000-1200 parts of high belite sulphoaluminate cement, 525-700 parts of nano activated fly ash, 465-600 parts of superfine slag, 45-78 parts of steel fiber, 28-63 parts of an expanding agent, 15-30 parts of a temperature-sensitive polycarboxylic acid water reducer, 78-95 parts of self-repairing microcapsules, and 284-325 parts of water. Wherein the self-repairing microcapsule is of a double-capsule-core and double-capsule-wall structure. The preparation method comprises the following steps: preparing the self-repairing microcapsule, mixing the cementing material, adding the water reducing agent and water, stirring, adding the microcapsule and the expanding agent, stirring, curing and the like. According to the invention, through a synergistic enhancement technology of a composite gel system, a multi-dimensional enhanced network and an environmental response technology, the material has the characteristics of rapid hardening and early strength, can be demolded within 2 hours, and solves the problems of long initial setting time, poor crack resistance, lack of self-repairing capability, high maintenance frequency and the like in repairing of the airfield pavement in the arid region.

The invention discloses steel, a steel pipe for hydrogen conveying and a preparation method of the steel pipe, and belongs to the technical field of pipelines. The steel comprises, by mass, not larger than 0.05% of C, 0.1%-0.3% of Si, 0.8%-1.3% of Mn, not larger than 0.02% of P, not larger than 0.01% of S, not larger than 0.03% of Al, not larger than 0.35% of Ni, not larger than 0.3% of Cr, not larger than 0.25% of Cu, not larger than 0.05% of V, not larger than 0.1% of Nb, not larger than 0.3% of Mo, not larger than 0.04% of Ti, not larger than 0.0003% of B and the balance Fe. The steel is suitable for preparing the hydrogen conveying pipeline, so that the steel is good in compatibility with the hydrogen environment and has the characteristics of excellent hydrogen induced cracking resistance, strength and toughness.

The invention provides low-temperature-resistant high-modulus rubber asphalt and a preparation method thereof, and relates to the technical field of rubber asphalt, and preparation raw materials of the low-temperature-resistant high-modulus rubber asphalt comprise the following components: matrix asphalt, rubber powder, a desulfurizer, a free radical type thermal initiation crosslinking agent, a reinforcing agent, a coupling agent, a flexibilizer, a viscosity reducer and an auxiliary agent. According to the low-temperature-resistant high-modulus rubber asphalt provided by the invention, the ductility at 5 DEG C is greater than 30cm, the maximum breaking flexural-tensile strain of a mixture at-10 DEG C is greater than 4000 mu epsilon, the dynamic modulus of the mixture at 15 DEG C is greater than 15000MPa, and the high-temperature performance and modulus of high-modulus asphalt concrete are not reduced while the crack resistance of the high-modulus asphalt concrete is helped to be improved. When being applied to pavement middle layer pavement, the pavement anti-cracking agent can improve the anti-cracking performance of the whole pavement structure, reduce the pavement maintenance cost and improve the driving safety.

The invention relates to the technical field of engineering performance intelligent detection, in particular to a concrete main tower circumferential prestressed reinforcement anti-cracking prediction method based on machine learning, which is characterized in that fiber grating strain sensors are arranged on the sections of main tower circumferential prestressed reinforcements, and strain data and environmental parameters in tensioning and operation stages are acquired; marking a cracking state to construct a sample data set; carrying out adaptive segmentation and abnormal value elimination operation on the strain sequence to realize data cleaning; constructing a cracking probability prediction model to process the cleaned data to obtain a cracking prediction probability; and calculating the total loss of the model, training the model, inputting newly collected data into the trained model, outputting a cracking prediction probability, and judging whether to carry out early warning or not. According to the method, online, real-time, intelligent and accurate prediction of the cracking risk of the circumferential prestressed steel bars of the concrete main tower can be realized, the monitoring false alarm rate is effectively reduced, and reliable technical support is provided for bridge operation maintenance and safety management and control.

The invention relates to the technical field of polyolefin cable materials, in particular to a photovoltaic weather-resistant anti-cracking low-smoke halogen-free flame-retardant polyolefin cable material and a preparation method thereof.The photovoltaic weather-resistant anti-cracking low-smoke halogen-free flame-retardant polyolefin cable material is prepared from, by weight, 90-150 parts of polyolefin resin, 1-3 parts of antioxidant, 2-5 parts of ultraviolet light absorber, 30-70 parts of composite flame retardant, 10-25 parts of carbon black and 3-5 parts of cross-linking agent; the composite flame retardant comprises a core material, a first shell material and a second shell material, the core material comprises a halloysite nanotube adsorbed with a flame retardant, the first shell material comprises epoxy resin, and the second shell material comprises maleic anhydride grafted polyethylene. According to the polyolefin cable material provided by the invention, the purpose of efficient flame retardance can be achieved by adding the halloysite nanotubes and the flame retardant system, the interfacial compatibility between the flame retardant and the matrix resin can be improved by adding the maleic anhydride grafted polyethylene, and the flame retardance of the polyolefin cable material can be improved by combining the added halloysite nanotubes and epoxy resin. The purpose of improving weather resistance, stress resistance and crack resistance of matrix resin is achieved.

The invention discloses anti-cracking concrete and a preparation method thereof, and the anti-cracking concrete is prepared from the following raw materials in parts by weight: 400-450 parts of cement, 600-700 parts of fine aggregate, 900-1000 parts of gravel, 70-80 parts of a composite additive, 30-40 parts of modified fiber, 4-5 parts of a water reducing agent and 160-180 parts of water, the composite additive is prepared from fly ash, modified sepiolite, calcium sulphoaluminate and an air entraining agent; the modified sepiolite is obtained by taking sepiolite as a raw material, pretreating the sepiolite through a silane coupling agent and then sequentially reacting the pretreated sepiolite with sulfanilamide and dodecyl chloride. According to the invention, through the synergistic effect of the composite additive and the modified fiber, the comprehensive improvement of the crack resistance and mechanical strength of the concrete is realized, in the composite additive, the moderate expansion of calcium sulphoaluminate compensates the early shrinkage stress, the microbubble system formed by the air entraining agent relieves the stress concentration, and the dispersion effect of the polycarboxylate superplasticizer is matched, so that the crack resistance and mechanical strength of the concrete are improved. The hardened body forms a compact and uniform microstructure, and the tensile strength of the concrete is improved.

The invention discloses a concrete crack resistance detection device for building civil engineering, and relates to the technical field of concrete performance detection.The concrete crack resistance detection device comprises a base, the upper surface of the base is sunken downwards to form a mounting groove, and the middle of the mounting groove is sunken downwards to form a first image acquisition chamber; the transparent aluminum oxide objective table is arranged in the mounting groove, and the concrete sample is arranged on the transparent aluminum oxide objective table; the first camera is arranged in the first image acquisition chamber, the image acquisition end of the first camera faces the transparent aluminum oxide objective table, and the first camera can acquire an image of the lower surface of the concrete sample; the heating mechanism is arranged in the transparent aluminum oxide objective table and / or on the lower surface of the transparent aluminum oxide objective table, and the heating mechanism is used for heating the sample to a target temperature; a pressing plate is arranged at the end of a telescopic rod of the hydraulic press, and the hydraulic press applies pressure to the upper surface of the sample through the pressing plate. Different stress conditions and different temperature and humidity environments can be accurately simulated, the cracking condition of the sample can be comprehensively observed, and large-batch tests can be carried out.

The invention discloses a high-flexibility anti-cracking coating and a preparation method thereof, and belongs to the technical field of building coatings. The coating is prepared from the following components in parts by mass: 50 to 70 parts of acrylic acid-organic silicon copolymer elastic emulsion with a core-shell structure, 3 to 8 parts of nano cellulose and polyester staple fiber composite fiber reinforced system, 20 to 30 parts of modified mica powder and fumed silica functional filler with a high radius-thickness ratio, 5 to 10 parts of auxiliaries and 10 to 15 parts of deionized water. A core layer of the elastic emulsion is a butyl acrylate-styrene elastomer, a shell layer of the elastic emulsion is a methyl methacrylate-organosiloxane copolymer, and a coating is endowed with high elongation at break and low-temperature crack resistance through the synergistic effect of a flexible network of the core layer and a rigid-flexible gradient structure of the shell layer. The nano cellulose and the polyester staple fiber form a dual-scale reinforcing system, so that cracks are bridged, and stress is dispersed; and the modified mica powder and fumed silica are compounded to improve the compactness and wear resistance of the coating.

The invention relates to the field of road maintenance engineering, in particular to anti-crack mortar for repairing road cracks and a preparation method of the anti-crack mortar. The anti-crack mortar for repairing the road cracks is prepared from the following raw materials in parts by mass: 90 to 130 parts of a gel material, 10 to 20 parts of a composite reinforcing agent, 120 to 180 parts of aggregate, 5 to 15 parts of a polymer auxiliary agent, 2 to 10 parts of propylene glycol, 0.3 to 0.8 part of a water reducing agent, 0.3 to 0.6 part of a retarder, 1.5 to 5 parts of a combined auxiliary agent, 20 to 40 parts of water and the like. The finally prepared anti-crack mortar not only has more excellent anti-crack performance, but also can keep good cohesiveness, has excellent adaptability and weather resistance in high and low temperature environments, is excellent in salt corrosion resistance and long in service life, reduces the maintenance frequency, and is suitable for large-scale popularization and application. The comprehensive performance requirements of the existing road maintenance engineering field on the anti-crack mortar for repairing are met.

The invention discloses a super-early-strength shrinkage-free high-crack-resistance tunnel spraying repair material in the technical field of civil engineering materials, which comprises the following raw materials in percentage by mass: 35-45% of sulphoaluminate cement; 8%-12% of a superfine early strength admixture; 2%-3% of a calcium sulphoaluminate expanding agent; 1%-2% of a magnesium oxide-based expanding agent; 1-2% of a calcium-magnesium composite expanding agent; 10%-15% of hollow glass beads; 1.5%-2.5% of copper plated steel fiber; 0.1%-0.3% of polypropylene fiber; 25%-30% of graded quartz sand; 0.5%-1.0% of a polycarboxylic acid water reducing agent; 3%-5% of an alkali-free liquid accelerator; 0.3%-0.8% of a thixotropic agent; and 0.1%-0.3% of a thickening time control agent. According to the method, a multi-scale performance cooperative regulation system is innovatively constructed. Through accurate control of the hydration process of a gel system, a shrinkage stress multi-stage compensation mechanism and systematic integration of a fiber-matrix interface strengthening technology, the mutual restriction relationship among early strength development, volume stability and crack resistance of a traditional material is broken through.

The invention discloses a preparation process of a high-strength anti-crack and anti-seepage vertical shaft lining concrete material, which comprises the following steps: (1) uniformly mixing aggregate with a solution containing copper ions, drying to remove moisture, dropwise adding saturated lime water containing alkaline substances into the mixture, and drying to remove moisture to obtain pretreated aggregate; and (2) the pretreated aggregate is placed in a carbon monoxide atmosphere for reduction treatment, the reduction temperature is higher than the melting point of copper, and the surface modified aggregate is obtained after reduction treatment is completed. The surface modified coarse aggregate and the surface modified fine aggregate are respectively prepared according to the method. And (3) uniformly mixing the cement binding material, the surface modified coarse aggregate, the surface modified fine aggregate, the modified fiber, the solid waste-based powder filler, emulsified asphalt and a water reducing agent, adding mixing water, and uniformly mixing to obtain the concrete material. The concrete material disclosed by the invention has good mechanical strength and crack resistance and also has good water seepage resistance, and the service life of the pumped storage power station vertical shaft is effectively prolonged.

The invention discloses a polymer emulsion composite modified road base material and a preparation method thereof, and belongs to the technical field of traffic infrastructure engineering materials. The polymer emulsion composite modified road base material is prepared from the following raw materials: graded aggregate, super sulfate cement or geopolymer cement, water for mixing, vinyl acetate-ethylene (VAE) copolymer emulsion and a silane coupling agent. The preparation method comprises the following steps: mixing the VAE emulsion with water for mixing to obtain a polymer diluent; mixing graded aggregate with an inorganic cementing material, then adding the polymer diluent, and mixing to obtain a mixture; and then paving, compacting, forming and curing are carried out. By forming a VAE flexible network-C-S-H / ettringite hybrid network, the material has the remarkable advantages of higher mechanical strength and low cost, and can greatly improve and enhance the crack resistance and durability of the road base.

The invention provides an anti-cracking performance evaluation method and system based on a concrete shrinkage rate. The method comprises the following steps: firstly, collecting shrinkage rate real-time sequence data and an acoustic emission signal flow of a concrete sample in a curing process, separating a high-frequency elastic wave energy attenuation characteristic value from the acoustic emission signal flow, and carrying out space-time coupling on the high-frequency elastic wave energy attenuation characteristic value and a shrinkage rate jump point in the shrinkage rate real-time sequence data to generate a crack initiation tendency index; then obtaining a calibrated crack initiation tendency index based on an ambient temperature hysteresis effect and a temperature drift error of the calibrated crack initiation tendency index, and then outputting an anti-crack performance grade according to a grading deviation degree between a pre-designed grading parameter and a fluctuation range of the calibrated crack initiation tendency index; according to the technical scheme provided by the invention, the essential defect that a traditional method cannot correlate material characteristics with environmental response is overcome, direct quantitative mapping of material structure performance and damage evolution is also realized, and a traceable material-level basis is provided for engineering anti-crack design.

The invention discloses a sealing silica gel ring anti-cracking performance detection device, and relates to the silica gel ring performance detection field, the sealing silica gel ring anti-cracking performance detection device comprises a detection table, a cylinder body and an external pressing mechanism, the external pressing mechanism comprises a U-shaped frame body and a pushing assembly, the inner side of the U-shaped frame body is provided with an accommodating groove, the pushing assembly comprises a connecting rod, one end of the connecting rod is rotatably connected with the U-shaped frame body, and the other end of the connecting rod is rotatably connected with the cylinder body; the other end of the connecting rod is rotationally connected with pushing wheels, and the two pushing wheels push the silica gel ring to enable the silica gel ring to arch outwards. Through the arrangement of the external pressure mechanism, the symmetrically distributed pushing wheels can hunch up part of the area of the silica gel ring, so that the crack detection capability is enhanced, closed or microscopic cracks on the surface of the silica gel ring can be effectively expanded, and the cracks are obviously amplified in the hunched parabola-like area; the silica gel ring is driven to roll continuously in the circumferential direction by combining the composite motion of rotation and axial movement of the barrel, it is ensured that the whole surface of the silica gel ring is subjected to the stretching and arching process, and a blind area of traditional single-point detection is eliminated.

The invention provides rubber-plastic composite modified asphalt suitable for low-temperature regions and a preparation method thereof, and belongs to the technical field of modified asphalt preparation. The modified asphalt is prepared from matrix asphalt, rubber powder, polyethylene and a compatibilizer, the content of the rubber powder is 15%-25% of the weight of the matrix asphalt, the content of the polyethylene is 4%-6% of the weight of the matrix asphalt, and the content of the compatibilizer is 5%-15% of the weight of the matrix asphalt; the preparation method comprises the following steps: heating the matrix asphalt to a flowing state, adding the rubber powder, stirring and swelling for 60 minutes, adding the polyethylene and the compatibilizer, stirring, and shearing at a high speed of 5000r / min for 45-60 minutes. Through rubber and plastic compound modification, the low-temperature crack resistance, the high-temperature stability and the water stability are excellent, the storage stability is good, the cost and pollution are reduced by utilizing waste materials, the process is simple, and the low-temperature road pavement material is suitable for road engineering in low-temperature areas.