158 results about "Resilient modulus" patented technology

The invention discloses a tire finite element modeling and multidirectional rigidity optimization method and system based on characteristic lines. The method comprises the following steps: extracting tire section characteristic lines from a three-dimensional digital model; introducing the tire section characteristic line into a finite element analysis environment, generating a three-dimensional tire geometric model by rotationally scanning the characteristic line, and performing grid division on the model; setting tire material attributes, performing zoning setting on the model according to a tire crown, a tire shoulder and a tire side wall, and setting tire thickness based on zoning; applying a constraint boundary condition at the center of the tire, and establishing a contact form of the tread and the ground; a progressive inflation pressure load is applied, the deformation state of the inflated tire is calculated, and longitudinal rigidity, radial rigidity and lateral rigidity calculation and analysis steps are set; the tire elasticity modulus and the cord fabric thickness are used as design variables, and an optimization algorithm is adopted to solve a multi-objective optimization function. The method has the advantages of being simple in modeling method and high in practical operability, the tire modeling threshold can be lowered, and the fund and time cost of refined modeling is reduced.

The invention relates to a comprehensive method for controlling non-stress cracks of a long concrete wall structure. The comprehensive method comprises the steps that S1, a construction flow section is divided; s2, low-early-stage elastic modulus concrete is poured at the bottom of the long wall to form a concrete transition layer, so that constraint on wall body concrete is reduced; s3, low-hydration-heat concrete is poured, and the temperature of the concrete entering a mold is controlled, so that upper concrete is formed; the low-early-stage elastic modulus concrete poured in the step S2 has the same strength grade as the low-hydration-heat concrete poured in the step S3, but the elastic modulus does not exceed 50% of the upper concrete poured at the same time within 48-72 h and does not exceed 70% in 7 d, the elastic modulus in 28 d is 90%-110% of the elastic modulus of the upper concrete, and the elastic modulus in 28 d is 90%-110% of the elastic modulus of the lower concrete. The low-hydration-heat concrete poured in the step S3 is prepared from moderate-heat cement or low-heat cement or by doping 35%-55% of fly ash into ordinary Portland cement, and the adiabatic temperature rise of the low-hydration-heat concrete is controlled to be not larger than 35 DEG C.

The invention discloses freeze-thaw resistant concrete for roads in cold regions and a preparation method of the freeze-thaw resistant concrete, and relates to the technical field of concrete. The preparation method comprises the following steps: carrying out dry mixing on the Portland cement, the kaolin and the silicon carbide whiskers, then adding the coarse aggregate and the fine aggregate, continuing to stir and mix uniformly to obtain a premix, then adding the water reducer and the water into the premix, and continuing to stir uniformly to obtain the freeze-thaw resistant concrete. A proper amount of silicon carbide whiskers are added into the mixed soil, the mixed soil has high strength, high elastic modulus and excellent chemical stability, and the freeze-thaw cycle resistance of the concrete can be remarkably improved through the effects of bridging micro-cracks, blocking crack propagation paths, improving pore structures and the like.

The invention relates to the technical field of road engineering, in particular to a detection method for evaluating cohesion characteristics of river-crossing shield tunnel waste slag improved soil for roadbed filling, which comprises the following steps: preparing a solidified soil sample; calculating coupling parameters; obtaining a static cohesion force and a dynamic cohesion force; obtaining a water stability coefficient; based on the collected roadbed filling characteristic parameters, the static cohesion, the dynamic cohesion and the water stability coefficient, constructing a dynamic resilience modulus correlation model; grading the cohesion characteristics of the solidified shield soil according to the coupling parameters and the dynamic rebound modulus; detecting actual values of the coupling parameters and the dynamic resilience modulus of the to-be-evaluated solidified soil, and determining the grade of the to-be-evaluated solidified soil; according to the cohesion characteristic detection method, the characteristics of shield tunnel soil particles, mineral composition and roadbed filling scenes are fitted, actual working conditions are simulated, and the solidification effect is quantified, so that a scientific basis is provided for engineering application of shield tunnel soil solidification improved roadbed, and the problems in the background technology are effectively solved.

The invention belongs to the technical field of high-performance cement concrete, and particularly relates to low-shrinkage hybrid fiber concrete and a use method thereof. The low-shrinkage hybrid fiber concrete is prepared by mixing cement, fly ash, sand, gravel, steel fibers, synthetic fibers, water and a water reducing agent according to the mass ratio of (410 to 390): (70 to 100): (780 to 750): (900 to 1100): (95 to 65): 1.1: (150 to 160): (8.9 to 7.5). According to the invention, the dispersibility of the steel fibers and the synthetic fibers can be ensured, and the workability of concrete construction is ensured. Hybrid fibers of the concrete have high tensile strength, development of bridge deck concrete cracks is effectively delayed, the fracture resistance of the concrete is improved, the elastic modulus of the concrete is also improved, and therefore the axial tensile strength of the concrete is also obviously improved; meanwhile, the shrinkage performance of the concrete is effectively improved, the durability of the concrete is improved, the service life of the concrete is greatly prolonged, other stress structures of the bridge are effectively protected, and then the overall service life of the bridge is prolonged.

The invention relates to the technical field of concrete durability evaluation, in particular to a compound green concrete salt freezing resistance durability evaluation system under a frozen soil environment, which comprises a data input unit, a decision information table storage unit, a rough set analysis processing unit and an evaluation output unit, the data input unit receives a sample data set containing freeze-thaw cycle times, dry-wet cycle times, freeze-thaw-dry-wet cycle times, long-term soaking time, composite salt concentration, gas content and fly ash mixing amount, and the decision information table storage unit stores a decision information table constructed based on a rough set theory. The influence factor combination and the relative dynamic elastic modulus percentage are associated, the rough set analysis processing unit establishes a mapping relation through attribute reduction and rule extraction and quantifies the weight of each factor, and the evaluation output unit outputs a relative dynamic elastic modulus predicted value, durability grade classification and key factor contribution sorting. And the salt freezing resistance durability of the concrete under the multi-factor coupling effect is accurately evaluated.

The invention discloses a non-dispersing agent for keeping concrete flowing in water, and belongs to the technical field of building materials, the non-dispersing agent comprises the following components by mass: 15-25% of an amphiphilic cellulose ether derivative; 10%-18% of a modified chitosan-acrylamide grafted copolymer; 8%-15% of a slow-release polycarboxylic acid water reducer; 5%-10% of nano silicon dioxide aerogel; 3%-8% of a bio-based delayed coagulation triggering agent; and 2%-5% of a self-repairing microbial capsule. Through a composite additive system, the loss rate of suspended solids is reduced to be within 1.2%, the slump loss within 2 hours is only 3%, and the problem of underwater segregation is solved; by utilizing a synergistic protection and self-repairing technology, the chloride ion diffusion coefficient is reduced by nearly 3 times, 0.3 mm cracks are repaired in 7 days, and the elastic modulus retention rate after freeze-thaw cycle reaches 91%. The underwater strength retention rate exceeds 95%, and the strength in 7 days reaches 80% of a design value. The ratio of the bio-based raw materials is 43%, the construction efficiency is improved by 87.5%, the cost in 30 years is reduced by 36.7%, and the method is widely applicable to environments and fills the blank of industrial test standards.

The present disclosure provides a rubber composition and a tire which can suppress changes in performances caused by changes in road conditions from dry to wet road surface or from wet to dry road surface. The tire of the present disclosure has E* when wet with water (MPa), E* when dry (MPa), tan δ when wet with water, tan δ when dry, 40% modulus (MPa) at 70° C. before a tensile test, and 40% modulus (MPa) at 70° C. after the tensile test which satisfy the following formulas (1) to (3):(1) E* when wet with water / E* when dry ≤0.90(2) tan δ when wet with water / tan δ when dry >1.00(3) 40% modulus at 70° C. after tensile test / 40% modulus at 70° C. before tensile test ≥0.45 whereE* and tan δ refer to a complex modulus of elasticity and a loss tangent, respectively, after 30 minutes from the start of measurement under the conditions of a temperature of 30° C., an initial strain of 10%, a dynamic strain of 1%, a frequency of 10 Hz, an elongation mode, and a measurement duration of 30 minutes;40% modulus at 70° C. after the tensile test refers to a tensile stress at an elongation of 40% determined after extension of 50% at 70° C., releasing the stress, and then measuring the tensile stress at an elongation of 40% at 70° C. in accordance with JIS K 6251:2010; and40% modulus at 70° C. before a tensile test refers to a tensile stress at an elongation of 40% measured before the tensile test at 70° C. in accordance with JIS K 6251:2010.

The invention relates to the technical field of nodular cast iron and an annealing method thereof, and discloses an annealing method for improving elastic modulus and strength of nodular cast iron and application, the annealing method comprises the following steps: first-stage annealing and high-temperature decomposition: heating to 880-980 DEG C along with a furnace, and preserving heat for 15-36 hours; second-stage annealing and low-temperature graphitization: cooling to 650-860 DEG C, preserving heat for 3-5 hours, and then quickly discharging from the furnace for air cooling; and performing surface treatment: performing shot blasting to remove oxide skin to obtain the nodular cast iron material. According to the scheme, the nodular cast iron material is prepared from the following raw materials in percentage by mass: 1.8 to 2.3 percent of C, 1.3 to 2.2 percent of Si, 0.3 to 0.7 percent of Mn, 0.002 to 0.005 percent of Bi, 0.002 to 0.01 percent of Sb, less than 0.06 percent of P, less than 0.2 percent of S and the balance of Fe. Compared with the prior art that two-stage annealing (such as furnace cooling to 595-635 DEG C after 900-950 DEG C treatment and heat preservation) needs to be matched with special components such as high rare earth and high phosphorus, the steps are complex and the cost is high, the phosphorus content and the rare earth content of the material in the scheme are low, the elastic modulus and the tensile strength of the nodular cast iron can be effectively improved by adding a proper amount of nodulizing agent, the production process is simplified, and the production cost is reduced. And the cost can be reduced.

The invention discloses a high-performance well cementation cement system for deep geothermal development, and relates to the technical field of well cementation materials for oil and gas field development. The well cementation cement system is prepared from the following components in parts by weight: 100 parts of a cementing material, 35 to 40 parts of a high-temperature reinforcing material, 7 to 10 parts of a high-thermal-conductivity toughening composite material, 0.5 to 1.5 parts of a suspension stabilizer, 0.3 to 0.6 part of a dispersing agent, 1.5 to 2.5 parts of a fluid loss agent, 1.0 to 2.5 parts of a retarder and 0.1 part of a de-foaming agent, the solid-to-liquid ratio of the well cementation cement system is 0.40 to 0.50. The high-temperature stability, corrosion resistance and long-term durability of the set cement can be guaranteed, and the heat conductivity of the set cement can be greatly improved. The cement slurry has the characteristics of higher high-temperature strength, low high-temperature strength decline rate, lower elastic modulus, high heat transfer efficiency and the like, can realize excellent engineering performance of the well cementation cement slurry under the condition of a hot dry rock high-temperature environment, and meets the engineering construction requirements.

A tire is provided which comprises a tread portion and a belt layer, wherein the tread portion has at least one rubber layer, the belt layer having a steel cord and a cap rubber covering the steel cord, a cap rubber layer forming a tread surface of the tread portion and the cap rubber are each composed of a rubber composition comprising a rubber component and a filler, wherein a complex elastic modulus at 70°C of the cap rubber (70°CE*1) is 15.0 MPa or less, and wherein in a case where W L in kg represents the maximum load capacity of the tire and 70 °C-tanδ1 represents a tanδ at 70 °C of the cover rubber, W L and 70 °C-tanδ1 satisfy the following inequality (1): 9.33 × 10 − 5 × WL − 70 ° C − tan δ 1 > 0.023

This invention relates to the field of concrete pouring technology, and discloses a method and system for regulating the cooling of hydration heat in large-volume concrete based on temperature difference control. The method includes the following steps: Step S101, constructing a thickness temperature profile; Step S102, calculating the zone temperature difference and the cooling rate in the middle section; Step S103, calculating the equivalent age field; Step S104, calculating the time-varying elastic modulus and relaxation time; Step S105, constructing a base constraint weighting function; Step S106, calculating the constrained viscoelastic thermal stress field; Step S107, calculating the potential energy centroid drift intensity; Step S108, outputting control commands. This invention achieves multi-factor coupled calculation and multi-objective collaborative optimization for regulating the cooling of hydration heat in large-volume concrete, ensuring that cooling regulation aligns with the core requirements of crack resistance in engineering projects, thereby reducing the possibility of hydration heat cracking in concrete.

The invention discloses anti-freezing and salt-tolerant high-strength concrete and a preparation method and application thereof, and belongs to the technical field of green high-strength concrete preparation, the anti-freezing and salt-tolerant high-strength concrete comprises, by mass, 400-500 parts of a cementing material, 650-700 parts of fine aggregate, 1000-1100 parts of coarse aggregate, 0.01-0.015 part of an additive and 160-180 parts of water, the fine aggregate comprises machine-made sand and / or river sand, and the coarse aggregate comprises water and / or water. The mass of the machine-made sand accounts for 50% of the total mass of the fine aggregate. The compressive strength, elastic modulus, chloride ion penetration resistance and carbonization depth of the concrete are improved by adopting a double-doping (slag ash and fly ash) or triple-doping (fly ash, slag ash and silica fume) mode, and the concrete is excellent in freezing resistance, wear resistance and permeability resistance.

The invention discloses a method for quickly constructing a pre-stressed system of a post-tensioned pre-stressed cover beam in winter, and belongs to the technical field of cover beam construction. Comprising the steps that S1, a steel reinforcement framework, prestressed pipes, prestressed steel bars and the like are fixed according to a cover beam design drawing; s2, a plurality of wireless temperature sensors are arranged on the bent cap steel bars for temperature monitoring; s3, determining raw materials and dosage of capping beam concrete, and mixing the concrete; s4, the cover beam concrete is transported; s5, cover beam concrete is poured; s6, the whole process from pouring to hardening of the bent cap concrete is subjected to heat preservation and maintenance; s7, setting a temperature matching maintenance test piece, and determining a tensioning opportunity according to the compressive strength and the elastic modulus of the test piece; s8, selecting a grouting opportunity according to the temperature monitored by the wireless temperature sensor; and S9, quick-hardening phosphate mortar is selected, heating and heat preservation measures are applied, and anchor sealing concrete construction is conducted. According to the method, the winter construction speed of the post-tensioned prestressed cover beam can be increased, and the construction quality is guaranteed.

This invention discloses a method and equipment for evaluating the tensile toughness of recycled asphalt mixtures, relating to the field of analytical techniques for recycled asphalt mixtures. The method includes: acquiring variables related to the internal structure and external environment of the recycled asphalt mixture to be evaluated; the variables related to the internal structure include: internal structural state variables, the length of the aggregate-binder two-phase interface transition zone, and the elastic modulus; the variables related to the external environment include: tensile strain ratio, loading frequency, and dynamic modulus; and calculating the tensile toughness evaluation value of the cold recycled asphalt mixture based on a predetermined multi-parameter coupling relationship using the variables related to the internal structure and the external environment. This invention introduces environmental factors and internal structural parameters of the recycled asphalt mixture to establish a multi-parameter tensile toughness evaluation model, fully considering the material composition, microstructural distribution characteristics, load factors, and ambient temperature of the recycled asphalt mixture under stress in the structural layer, enabling accurate evaluation of the tensile toughness of the recycled asphalt mixture.

The present invention provides a method for testing micro-creep in a concrete interface transition zone, which relates to the field of mechanical testing technology. The method comprises using a nanoindenter to perform a nano-indentation test on a polished concrete sample to determine the boundary between the concrete sample aggregate, the interface transition zone, and the cement mortar, thereby obtaining the width of the interface transition zone; using a nano-indentation rectangular grid to assist in locating the coordinates of the indentation center of the micro-creep test; calculating the maximum load of the micro-creep test based on the water-cement ratio of the concrete, the width of the interface transition zone, the average elastic modulus in the interface transition zone, and the average elastic modulus in the cement mortar; and performing a micro-creep test on the micro-creep test area to obtain a contact creep function and a contact creep modulus of the interface transition zone. The present invention can accurately locate the indentation center of the micro-creep test in the concrete interface transition zone, and the test results obtained by the micro-creep test have low discreteness, and can accurately reflect the creep performance of the interface transition zone.

The invention belongs to the technical field of building materials, and relates to impermeable high-strength concrete and a preparation method thereof. The invention provides impervious high-strength concrete which is prepared from the following components in parts by mass: 150 to 200 parts of cement, 80 to 100 parts of organic and inorganic composite modified bentonite, 900 to 1300 parts of fine aggregate, 230 to 340 parts of coarse aggregate, 2 to 10 parts of additive and 250 to 350 parts of water, the organic and inorganic composite modified bentonite is obtained by modifying bentonite with polyepichlorohydrin dimethyl ammonium and then modifying the modified bentonite with hydroxyl polyaluminum chloride. The invention aims to solve the technical problem that the compressive strength and the elastic modulus of the concrete for the underground diaphragm wall are almost synchronously reduced along with the increase of the use amount of bentonite, so that the compressive strength and the elastic modulus are difficult to consider at the same time.

The invention relates to the technical field of engineering materials, and provides anti-cracking steel slag asphalt concrete and a preparation method thereof. The anti-cracking steel slag asphalt concrete is prepared from, by weight, 4-6 parts of asphalt, 5-10 parts of filler and 60-70 parts of aggregate, the filler is prepared from, by weight, 20-30 parts of steel slag powder, 20-25 parts of limestone powder, 0.3-0.5 part of polypropylene fiber and 0.3-0.5 part of dispersing agent, and the polypropylene fiber is composed of first polypropylene fiber and second polypropylene fiber. The elastic modulus and the fiber length of the first polypropylene fiber are different from those of the second polypropylene fiber. According to the technical scheme, the problem of insufficient cracking resistance of the steel slag asphalt concrete in related technologies is solved.

The application discloses a kind of shotcrete and its preparation method, belong to building material technical field.It mainly includes the following weight parts of raw materials made: Portland cement 200~260 parts, fine sand 240~280 parts, 260~300 parts of gravel, fly ash 10~35 parts, composite steel fiber 5~10 parts, admixture 10~15 parts, no alkali accelerator 2~5 parts, water reducing agent 1~3 parts and water 80~110 parts.The shotcrete provided by the application adopts steel fiber and has excellent tensile strength and elastic modulus and other characteristics, and the composite steel fiber forms a three-dimensional network structure in the concrete to support the concrete;After adding fly ash and admixture to the concrete, it is beneficial to improve the compactness of the concrete, promote the development of early strength, and improve the compressive performance of the concrete.

The application discloses an interface adhesive as well as a preparation method and application thereof, and belongs to the technical field of concrete. A component A contains E-51 epoxy resin, elastic modulus enhancer a (a composite of single-sulfur calcium sulphoaluminate and high-sulfur calcium sulphoaluminate) and bonding enhancer b (nanoscale gel), etc.; a component B is a polyamide curing agent and a modified aromatic amine curing agent. The adhesive has an elastic modulus of about 40 GPa, is between UHPC and NC, can relieve interface stress concentration, can permeate and block microcracks at the same time, and can significantly improve bonding strength and durability. When the adhesive is prepared, the component A and the component B are stirred respectively, are mixed in proportion, and are vacuum degassed, and the adhesive is obtained. When the adhesive is constructed, the adhesive is coated on the surface of existing ordinary concrete first, and then an ultrahigh performance concrete reinforcing layer is poured.

The application discloses an anti-impact and abrasion material and a preparation method thereof. The anti-impact and abrasion material is prepared from the following components in parts by weight: 40-45 parts of low-heat Portland cement with a strength grade not lower than 42.5, 8-13 parts of mineral admixture, 2-5 parts of barium sulfate, 37-43 parts of fine aggregate, 0.2-0.5 parts of water reducing agent, 0.1-0.3 parts of wetting agent, 0.1-0.8 parts of coagulant, 0.01-0.05 parts of reactive air-entraining material, 0.1-0.3 parts of air bubble inhibitor, 0.1-0.5 parts of nanometer material, 0.3-1.0 parts of redispersible latex powder, 2-5 parts of modified organic aggregate, 0.01-0.05 parts of cellulose ether, 0.3-0.8 parts of composite fiber, 1.0-3.0 parts of internal water-retaining agent and 14-18 parts of water. The application reduces the elastic modulus of the material and improves the impact toughness of the material under the premise of ensuring the crack resistance of the material, and the material is high-strength and dense, and can resist the impact and abrasion damage of media.

Tire (1) for construction vehicle comprising two working layers (321, 322), comprising metallic reinforcements and at least two shrink-fit layers (331, 332), of axial widths less than those of the working layers (321, 322), and comprising metallic reinforcements, the innermost radial shrink-fit layer (332) being the shrink-fit layer of greatest axial width. At each axial end of the innermost radially enclosing layer (332), two contiguous rubber mixtures (51, 52, 61, 62), or decoupling mixtures, are arranged, one being radially inside the other, the decoupling mixture (51, 61) furthest radially from the end of the enclosing layer (332) has a dynamic modulus of elasticity measured at 23°C and 10% strain and at 10 Hz, at most equal to 0.7 times the dynamic modulus of elasticity of the decoupling mixture (52, 62) closest radially to the end of the innermost radially oriented shrinkage layer (332). Abstract figure: Figure 1.

The application discloses a kind of low modulus high ductility super-retarding concrete, the concrete includes by weight ratio: cement 254~360 parts, fly ash 68~108 parts, slag powder 68~70 parts, 5~16mm gravel 352~393 parts, 16~25mm gravel 660~729 parts, medium sand 669~705 parts, rubber powder 20 parts, polystyrene plastic 15 parts, water 150 parts, water reducing agent 5.9~7.5 parts, super-retarding agent 3.1~4.0 parts, water-based polyurethane 15 parts, nano composite hydrogel 15 parts, polyolefin elastomer 5 parts, polypropylene fiber 1.0 part, can have higher toughness, lower elastic modulus, and can reach design requirement strength and durability, simultaneously, when practical application, first, a layer of low modulus high ductility super-retarding concrete is poured, then continue to pour ordinary concrete, combined with other anti-cracking measures, can effectively reduce the constraint degree of bottom plate to upper portion, prevent temperature cracks.

The invention provides a nanoindentation testing method for a composite asphalt mixture, and relates to the technical field of asphalt material performance research. The method comprises the following steps: S1, preparing a double-solid waste epoxy resin composite asphalt mixture test piece; s2, grinding and polishing the test piece by adopting a step rotating speed and composite lubricating liquid synergistic process so as to obtain the surface smoothness meeting the nanoindentation test requirement; s3, acquiring a macroscopic elastic modulus of the test piece, and automatically generating nanoindentation test parameters according to the macroscopic elastic modulus through a pre-established Sigmoid mapping model; and S4, carrying out nanoindentation test according to the test parameters so as to evaluate the micro-mechanical properties of the asphalt mortar, the aggregate and the interface transition area. By reasonably designing the mix proportion and the production process, efficient utilization of the waste asphalt pavement material and the steel slag is achieved, the resource utilization rate is increased, sustainable development is promoted, and a high-performance, economical and environment-friendly solution is provided for road maintenance and repair engineering under complex climate conditions.

The present invention addresses the problem of providing a tire capable of improving the overall performance of low fuel consumption performance and wear resistance performance. [Solution] A tire provided with a tread portion having at least one rubber layer, in which the ratio (G / WL) of the tire weight G (kg) to the maximum load capacity WL (kg) of the tire is 0.0160 or less, the cross-sectional width Wt of the tire is 200 mm or more, a first layer constituting the tread is composed of a rubber composition containing a rubber component and a filler, the thickness t1 of the first layer is greater than 3.0 mm, and the thickness t2 of the first layer is greater than 3.0 mm. When the complex elastic modulus of the rubber composition at 30 DEG C is 30 DEG C E * (MPa) and the ground contact ratio on the ground contact surface of the tread portion is R, 30 DEG C E * is greater than 8.0 MPa, and the product of R and 30 DEG C E * (R * 30 DEG C E *) is greater than 5.0.

The invention discloses a preparation method of anti-freezing concrete suitable for a high-altitude environment. The preparation method comprises the following steps: firstly, carrying out pre-water absorption treatment on coarse aggregate to obtain pre-treated coarse aggregate, wherein the pre-water absorption rate is 1.5 times of the saturated surface dry water absorption rate; mixing the anti-freezing fiber and the bubble stabilizer; and finally adding the cementing material, the water, the fine aggregate and the additive, and mixing to obtain the concrete. The bubble stabilizer is superfine particles, and the anti-freezing fibers comprise low-elastic-modulus fibers and high-elastic-modulus fibers. By adding the fiber combination, the air entraining agent can be assisted in introducing more beneficial bubbles in the stirring process, a dense network is formed in a concrete mixture and a cement matrix, the bubbles introduced under low air pressure are prevented from overflowing, and meanwhile, the air hole structure of the concrete is optimized through the bubble stabilizer to maintain the air content of the concrete. The fiber composition has a synergistic effect in the hardened concrete, and under the combined action of the fiber composition and the hardened concrete, the anti-freezing durability of the concrete in the high-altitude low-air-pressure environment is remarkably improved.

The present invention provides a method for preparing a high-modulus, high-strength, and high-fatigue-resistant aluminum-based composite sheet. The method comprises subjecting an in-situ ceramic particle-reinforced aluminum-based composite material to a sequential semi-continuous casting, hot rolling, cold rolling, solution treatment, cold rolling, and aging treatment. The method for preparing the aluminum-based composite sheet provided by the present invention features a simple and rational process. The non-uniform distribution of in-situ ceramic particles forms a two-stage heterogeneous structure with a non-uniform grain distribution, achieving a multi-layered reinforcement structure and a microstructure that inhibits fatigue crack propagation. This method simultaneously improves the elastic modulus, tensile strength, fatigue limit strength, and fatigue crack propagation resistance of the aluminum-based composite sheet, and can be industrially produced using existing industrial equipment.

This application relates to a method and system for designing the mix proportion of cement emulsified asphalt mortar for high-speed railways. The method includes the following steps: inputting design factors of the cement emulsified asphalt mortar to be designed into a design model; the design factors include raw material types, quantities, and environmental parameters; predicting and outputting performance indicators corresponding to the cement emulsified asphalt mortar to be designed through the design model; the performance indicators include fluidity, spreadability, working time, compressive strength, elastic modulus, and fatigue life; adjusting the design factors of the cement emulsified asphalt mortar to be designed according to the performance indicators and inputting them into the design model to obtain the performance indicators corresponding to the adjusted design factors; repeating the input and adjustment steps multiple times until the optimal design factors that meet the performance requirements are obtained and output. The system and equipment are used to execute the above method. This application has the advantages of high design efficiency, short cycle, low cost, and high accuracy.

The present application provides a corrugated steel web box girder lining concrete cracking risk analysis method and system, sets up displacement boundary conditions and temperature boundary conditions, establishes a corrugated steel web lining concrete model, carries out numerical calculation on the corrugated steel web lining concrete model, analyzes the numerical calculation results; based on the numerical calculation results, taking shrinkage effect, creep, concrete mold temperature and concrete surface heat preservation measures as the consideration factors, the influence of each consideration factor on the cracking risk of corrugated steel web lining concrete is analyzed; according to the influence of each consideration factor, the cracking risk of target corrugated steel web lining concrete in target environment is determined and adjusted. The present application analyzes the influence of hydration heat release efficiency, elastic modulus change and shrinkage and creep behavior of concrete on the crack resistance of lining concrete, which helps to determine the cracking risk.

This invention discloses a design method for pile-slab bridge deck pavement, belonging to the interdisciplinary field of engineering design and artificial intelligence. Specifically, it includes: data acquisition and preprocessing to establish a standardized design database; constructing a classification prediction model, completing model training and optimization; selecting core feature variables through intelligent feature importance analysis; calculating the pile-slab collaborative stress coefficient and predicting the equivalent elastic modulus of the pavement layer; calculating key parameters and iteratively optimizing the model; predicting and verifying the pavement layer thickness and material ratio parameters; calculating bond strength and predicting service life to ensure that design requirements are met; and completing final parameter optimization, outputting a final design scheme including core parameters, material ratios, and construction suggestions. This invention solves the problems of traditional design relying on experience, low accuracy, and difficulty in quantifying multi-parameter coupling, improving design efficiency and accuracy, extending the service life of the pavement layer, and is applicable to the pavement pavement design of various highway and municipal pile-slab bridges.