787 results about "Pitch blende" patented technology

The utility model relates to the technical field of asphalt stirring processing, in particular to an asphalt mixture heating regeneration stirring cylinder and stirring equipment. The stirring device comprises a cylinder body, wherein a stirring cavity is formed in the cylinder body; the stirring assembly is arranged in the stirring cavity, the stirring assembly comprises a stirring shaft, the stirring shaft penetrates through the cylinder body and the stirring cavity, a plurality of stirring arms are evenly distributed on the part, located in the stirring cavity, of the stirring shaft, and stirring blades are arranged on the stirring arms; the cover plate is arranged on the stirring cavity, and a microwave heating magnetron is arranged on the cover plate. The microwave heating magnetron is arranged on the cover plate at the top of the stirring cylinder, and microwave energy is converted into heat energy, so that an asphalt mixture in the stirring cylinder is uniformly heated, the flowability of the asphalt mixture is improved, the bonding phenomenon of the inner wall of the stirring cylinder and the stirring shaft is reduced, and the uniform stirring condition of the asphalt mixture is greatly improved; the stirring quality and the production efficiency of the stirring shaft equipment are improved.

The invention discloses a composite modified waste cooking oil biological asphalt mixture and a preparation method thereof. The asphalt mixture comprises the following substances in percentage by mass: 4-7wt% of biological asphalt, 89-92wt% of aggregate, 2-3wt% of mixed mineral powder and 0.5-1.0 wt% of lignin fiber, the biological asphalt is prepared from the following substances in percentage by mass: 50 to 58 weight percent of matrix asphalt, 18 to 20 weight percent of waste cooking oil, 15 to 18 weight percent of mixed rubber powder, 2 to 2.5 weight percent of polymer modifier, 6 to 8 weight percent of mixed resin and 1 to 1.5 weight percent of additive. The preparation method comprises the following steps: preparing biological asphalt; respectively putting the aggregates with various grades of particle sizes, the mixed mineral powder and the biological asphalt into a drying oven for heating; sequentially putting the biological asphalt and the aggregate with various grades of particle sizes into a mixing pot, and mixing; sequentially adding the mixed mineral powder and the lignin fiber into the mixing pot, and continuously mixing to obtain the composite modified waste cooking oil biological asphalt mixture. The biological asphalt is prepared in a layer-by-layer progressive mode, and the technical problem that the doping amount of the waste cooking oil and the performance of the biological asphalt are difficult to achieve balance is solved.

The invention discloses an efficient preparation and construction optimization system and method for a cold patch asphalt mixture, and belongs to the technical field of construction optimization. Environmental parameters of a construction site are collected, including altitude, an air pressure correction coefficient and a light volatile factor, and a multi-scale mixture model coupled with air pressure response is constructed; analyzing the volatilization path, the structural stability and the initial bonding strength of the mixture in combination with discrete elements and fluid mechanics simulation, and further extracting a structural retention threshold value and reversely deducing the proportion adjustment amount of medium-high boiling point solvent components; meanwhile, a microcapsule controlled release technology is adopted to delay release of light components, adaptive construction parameters are output based on a simulation platform and a machine learning model, the paving temperature and the compaction frequency are dynamically optimized, and efficient cooperation and intelligent regulation and control of the cold patch material performance and the site construction technology are achieved.

The invention relates to an asphalt mixture, in particular to a modified heavy-load asphalt mixture based on a basalt fiber composite material as well as a preparation method and application of the modified heavy-load asphalt mixture. The modified heavy-load asphalt mixture based on the basalt fiber composite material is prepared from the following raw materials in parts by weight: 10 to 15 parts of asphalt, 1 to 3 parts of modified basalt fiber, 1 to 3 parts of aminated chitin whisker, 85 to 90 parts of mineral aggregate, 5 to 8 parts of hollow glass microspheres, 3 to 6 parts of compatilizer and 1 to 3 parts of stabilizer. Wherein the modified basalt fiber improves the low-temperature crack resistance, high-temperature rutting resistance and water stability of the asphalt mixture, and the aminated chitin whisker improves the fatigue resistance of the asphalt mixture.

The invention discloses a high-dosage RAP recycled asphalt mixture and a preparation method thereof, and the method comprises the following steps: step 1, carrying out homogenization treatment on an epoxy resin system and a rubber-asphalt composite system according to a weight ratio of 1: 5-1: 30 to obtain a composite modified asphalt system; 2, preheating the waste asphalt pavement material to 110-130 DEG C, performing dry mixing, adding a petroleum ether regenerant, heating to 150-170 DEG C, and performing dry mixing again to obtain a mixture 1; step 3, preheating new fine aggregate, coarse aggregate and steel slag in batches, adding into the mixture 1, and carrying out dry mixing to obtain a mixture 2 with a primary grading framework; step 4, adding the composite modified asphalt system prepared in the step 1 into the mixture 2, and performing wet mixing to obtain a mixture 3; and step 5, homogenizing the mixture 3 to finally obtain the target recycled asphalt mixture. The invention aims to realize high-mixing-amount recycling of the waste asphalt pavement material.

The invention discloses a lignin fiber reinforced environment-friendly asphalt mixture and a preparation method thereof, belongs to the technical field of asphalt preparation, and is used for solving the technical problem that the high temperature resistance and the tensile property of an asphalt mixture in the prior art need to be further improved. The composite lignin fiber modified asphalt is prepared from the following raw materials in parts by weight: 5 to 6 parts of matrix asphalt, 3 to 5 parts of composite lignin fiber, 2 to 4 parts of composite hollow microspheres and 81 to 102 parts of auxiliary materials, an organic metal framework is modified by utilizing a silane coupling agent, and a stable modification structure is formed on the modified lignin fiber by a modified hydrophobic framework through hydrolysis under an alkaline condition, so that the composite lignin fiber modified asphalt is obtained. The composite hollow microspheres are prepared through an emulsion polymerization method, and the composite hollow microspheres and the composite hollow microspheres are used as additives to be mixed with materials, so that the high-performance asphalt composite material is finally prepared.

The invention belongs to the technical field of engineering material detection, and particularly discloses an asphalt mixture dynamic water stability comprehensive detection system which comprises a standard test piece preparation module, a dynamic load loading module, a diffusion behavior analysis module, a sealing failure verification module and a water stability evaluation module. A detection area is limited through closed sealing treatment, a staged progressive increase dynamic load is applied to simulate an actual working condition, a three-dimensional moisture diffusion map is constructed to analyze diffusion behavior parameters, and a dynamic water stability grade evaluation result is generated in combination with an intelligent matching algorithm. According to the method, edge water seepage interference can be effectively avoided, the moisture diffusion process is accurately monitored, the performance of the asphalt mixture is comprehensively evaluated, and a scientific basis is provided for pavement structure design and material optimization.

The invention relates to a mix proportion design method of an MS-CAVF asphalt mixture. The mix proportion design method comprises the following steps: selecting raw materials; grading the coarse aggregate, and determining the use amount of the coarse aggregate in each grade through a partial normal distribution curve; measuring the apparent density # imgabs0 # of the coarse aggregate, the apparent density # imgabs1 # of the fine aggregate, the apparent density # imgabs2 # of the mineral powder, the asphalt density # imgabs3 # and the tight loading density # imgabs4 # of the coarse aggregate; the use amount of asphalt # imgabs 5 #, the use amount of mineral powder # imgabs 6 #, the use amount of cement # imgabs 7 # and the design void ratio # imgabs 8 # are initially prepared; and calculating the use amount # imgabs9 # of the coarse aggregate and the use amount # imgabs10 # of the fine aggregate by using a CAVF method, and calculating to obtain the synthetic gradation. The processing technology and quality of the coarse aggregate are improved, the CAVF method is combined with the optimal design of partial normal distribution gradation, and based on the wide-scale gap gradation design concept and the center particle size design concept, the embedding and extruding capacity of the asphalt mixture is improved, large internal friction resistance is formed, and the uniformity of the road surface structure is improved.

The invention relates to the technical field of modified steel slag powder, and discloses a preparation method of modified steel slag powder applied to a cold-mixed full-steel-slag asphalt mixture, which comprises the following preparation steps: 1) stirring and mixing 80-90 parts by mass of steel slag, 10-20 parts by mass of waste slurry powder particles and 1-2 parts by mass of triethanolamine in a stirring drum to form a mixture; 2) grinding the mixture in a ball mill for a set time to form powder; 3) drying the powder in a dryer to obtain modified steel slag powder; through the preparation steps, the activity, the particle distribution uniformity, the compatibility with the emulsified asphalt and the chemical stability of the modified steel slag powder are remarkably improved, so that a higher-quality material choice is provided for the application of the cold-mixed full-steel-slag asphalt mixture.

The invention discloses an asphalt mixture component segmentation method, device and equipment, and relates to the technical field of asphalt pavement construction control, and the method comprises the steps: obtaining an initial two-dimensional image of an asphalt mixture section, and carrying out the preprocessing of the initial two-dimensional scanning image, and the preprocessing comprises the contrast enhancement and light field correction. Component division is carried out on the preprocessed image through a double-threshold segmentation method, morphological post-processing is carried out on the initial segmentation image, and each separated component segmentation image is obtained; and calculating the difference value between the image area ratio and the actual volume ratio of each component segmentation image, and calculating the relative error between the image screening grading and the actual screening grading of the aggregate components. When the difference value or the relative error exceeds the preset threshold range, the image processing parameters are adjusted, the segmentation operation is executed again, the target segmented image is obtained, the difference value and the relative error of the target segmented image are both within the preset threshold range, and the problem that the segmentation precision of the asphalt mixture components is insufficient is solved.

The invention belongs to the technical field of road traffic, and particularly relates to a wet mixing test method for measuring the skeleton void rate of a flowing mortar asphalt mixture. According to the method disclosed by the invention, a small amount of asphalt is added in the aggregate mixing process, so that the coarse and fine aggregates have certain adhesion capacity without influencing the arrangement of the coarse and fine aggregates, a certain lubrication effect is provided for the surfaces of the coarse aggregates with relatively large particles, and the influence caused by friction of the surfaces of the coarse aggregates is reduced; and finally, uniformly mixing the aggregate and the asphalt, pouring the mixture into a mold according to a set weight, and compacting by using a Marshall compactor or a rotary compactor, so that errors caused by human factors are reduced.

The invention provides an all-component multi-source solid waste asphalt mixture design method and system, and relates to the technical field of data processing, and the method comprises the steps: carrying out the preprocessing of obtained test proportion data of a solid waste asphalt mixture, and generating a mixture data set; screening the mixture data set by using a preset constraint condition to obtain a plurality of candidate matching points meeting the performance index characteristics; the performance index characteristics comprise gradation structure characteristics related to particle size, bonding system characteristics related to high-temperature fluidity and water sensitivity, molding volume and construction characteristics related to porosity and saturation, and context embedding characteristics related to a service scene; splicing the performance index features and inputting the spliced performance index features into a trained gating expert network to obtain a corresponding performance prediction mean value and a performance fluctuation mean value; and performing reliability analysis on the candidate matching points based on the performance prediction mean value and the performance fluctuation mean value, and determining the candidate matching points of which the reliability is greater than a preset threshold value as target matching points.

The invention discloses a hard asphalt mixture and a preparation method thereof, and belongs to the technical field of road engineering materials. Aiming at the problems of insufficient strength, stability and durability of the existing hard asphalt mixture, the method comprises the following steps: grading and mixing basalt and diabase composite coarse aggregate, medium aggregate with a specific ratio, fine aggregate containing basalt mineral fibers and limestone mineral powder; the preparation method comprises the following steps: heating to 175-185 DEG C, adding modified asphalt prepared by shearing and blending matrix asphalt and a styrene-butadiene-styrene block copolymer modifier, carrying out dry mixing and wet mixing, scattering lignin fibers, and carrying out thermal insulation aging and three-stage compaction molding. Wherein the rotating speed and time of dry mixing and wet mixing are controlled, the compaction is divided into initial pressing, re-pressing and final pressing stages, and different pressures are set. According to the preparation method, the performance of the mixture is improved by optimizing aggregate composition, a modified asphalt process and mixing and compacting parameters, and the preparation method is mainly used for road engineering construction with high requirements on pavement strength and stability.

The invention belongs to the technical field of RAP recycled asphalt mixtures, and particularly relates to a high-dosage RAP recycled asphalt mixture for alpine regions and a preparation method of the high-dosage RAP recycled asphalt mixture. The high-dosage RAP recycled asphalt mixture for the alpine region is characterized by comprising the following components in percentage by mass: 50-60% of RAP, 3-6% of mineral powder, 1-3% of new asphalt, 1-2% of a composite regenerant, 1-2% of a modifier and the balance of a new aggregate, the composite regenerant is composed of pine tar, plant-based epoxy ester oil, cashew nut shell oil and a penetrant. The modifier is prepared from regenerated low-density polyvinyl chloride, hyperbranched epoxy resin and liquid polybutadiene rubber coated waste rubber powder. According to the technical scheme provided by the invention, the technical problems of poor low-temperature performance, water stability and freeze-thaw cycle stability when a high-dosage RAP recycled asphalt mixture is used in an alpine region are solved.

The invention relates to the technical field of asphalt mixtures, and discloses a preparation method of a cold-mixed full-steel-slag asphalt mixture, which comprises the following preparation steps: 1) adding coarse steel slag and fine steel slag into an asphalt stirring pot according to parts by mass, and stirring to form mixed steel slag; 2) stirring and mixing the modified steel slag powder, polydimethylsiloxane, fly ash, hydrogen peroxide and the mixed steel slag in parts by mass to form a first part of mixture, and taking out the first part of mixture for later use; (3) stirring the emulsified asphalt, the water-borne epoxy resin, the water-borne curing agent and the defoaming agent in parts by mass to form a secondary mixture; 4) stirring and mixing the first part of mixture and the second part of mixture, then adding the modified steel slag powder, and stirring and mixing to form a cold-mixed full-steel-slag asphalt mixture; through specific preparation steps and material proportioning, the performance of the cold-mixed full-steel-slag asphalt mixture is comprehensively optimized, and the construction workability, durability, fatigue resistance and water damage resistance are improved.

The invention provides a method and a device for evaluating low-temperature performance under the expansion characteristic of a steel slag asphalt mixture, and relates to the field of road engineering. The method comprises the following steps: acquiring a first volume expansion rate data set in a first time period according to the type of a target mixture test piece; according to the first volume expansion rate data set, a second volume expansion rate data set of the target mixture test piece in the second time period is obtained through a volume expansion rate prediction model; according to the first volume expansion rate data set and the second volume expansion rate data set, low-temperature performance evaluation index data under the expansion rate corresponding to the target mixture test piece are obtained through the target testing device; performing principal component optimization on the index data through a principal component analysis method, and obtaining low-temperature performance evaluation index data corresponding to the optimized expansion rate; and performing low-temperature performance evaluation operation by optimizing the low-temperature performance evaluation index data corresponding to the expansion rate. The problem that low-temperature performance judgment is inaccurate in an existing low-temperature performance testing method is solved.

The invention discloses an early strength type modified emulsified asphalt mixture and a preparation method thereof, the content of each substance in the asphalt mixture is as follows: 70-80 wt% of aggregate, 8-12 wt% of SBS modified emulsified asphalt, 8-10 wt% of an early strength agent and 4-8 wt% of mineral powder, the addition amount of the early strength agent is increased along with the increase of the addition amount of the SBS modified emulsified asphalt, and the addition amount of the mineral powder is increased along with the increase of the addition amount of the SBS modified emulsified asphalt. When the addition amount of the SBS modified emulsified asphalt is increased by 1 wt%, the addition amount of the early strength agent is correspondingly increased by 0.4-0.6 wt%. The preparation method comprises the following steps: preparing SBS modified asphalt and preserving heat for later use; preparing SBS modified emulsified asphalt, and sealing and storing; preparing an early strength agent and storing at normal temperature for later use; the aggregate, the early strength agent and the mineral powder are put into a mixing pot to be stirred; and adding the SBS modified emulsified asphalt into the mixing pot, and continuously stirring to obtain the early-strength modified emulsified asphalt mixture. The emulsified asphalt mixture prepared by the invention has the advantages of high initial strength, quick strength increase, good pavement performance and the like, can be used for paving an upper surface layer of a high-grade pavement, and can quickly open traffic after paving.

The invention discloses a method for quantifying the damage contribution rate of each component in a recycled asphalt mixture, which comprises the following steps: analyzing each component in the recycled asphalt mixture, preparing a single-component material test piece and an interface test piece between different materials, carrying out shearing and tensile tests on the test pieces, introducing a DIC technology to obtain a strain field on the surface of the test piece, and quantifying the damage contribution rate of each component in the recycled asphalt mixture. Collecting peak frequency data points according to an acoustic emission sensor, and performing K-means clustering processing under an unsupervised condition to obtain a peak frequency data range; carrying out a semicircular bending test on the mixture test piece, collecting peak frequency data points according to an acoustic emission sensor, and carrying out K-means clustering processing under a supervised condition to obtain a data cluster and a peak frequency data range; judging each data cluster, and quantifying the damage contribution rate of each component material and interface in the mixture; the quantitative result obtained by the method can provide a theoretical basis for targeted optimization design of the recycled asphalt mixture, the operation is simple, and the principle can be applied to detection of internal damage conditions of other multiphase body materials.

The invention provides a method for analyzing and predicting the water stability of an asphalt mixture, which comprises the following steps of: acquiring multi-dimensional service environment, material composition and standard water stability test data, and carrying out standardization and stratified sampling division on the multi-dimensional service environment, the material composition and the standard water stability test data; a context sensing multi-layer perceptron network supporting feature parameter sharing and gradient accumulation is constructed, and the importance weight of each dimension of features under different data distributions is automatically evaluated and normalized. An attention mechanism and a graph convolutional network are introduced, association between features is quantified, and a key high-order interaction relationship is deduced; by means of K-fold cross validation and meta-learning optimization, the generalization ability of the model for new distribution data is improved, prediction accuracy and feature interpretation are improved, and intelligent analysis and proportion design of the water stability of the asphalt mixture are promoted.

The invention discloses a series grading asphalt mixture design method. The mineral aggregate gradation can be designed according to the performance requirements of the asphalt mixture, and the accuracy and operability of the gradation design are improved; the composition of the mixture is quantitatively designed according to the Marshall stability requirement, so that the workload of composition design is greatly reduced, and the controllability of the high pavement performance of the asphalt mixture is improved; the high-temperature stability and the water stability of the mixture are checked according to the preset composition, blindness of mixture composition adjustment is avoided, the success rate of pavement performance verification of the mixture is improved, and the performance verification period is shortened. According to the method, the composition design of the asphalt mixture can be guided, the composition of the mixture can be accurately controlled, the pavement performance of the mixture can be quantitatively designed and controlled, and the pavement performance of the asphalt mixture can be efficiently and comprehensively coordinated.

The application provides a regenerative asphalt mixture prefabricated member forming device, which comprises a rotating disc mechanism, the rotating disc mechanism is provided with a rotating disc support, the upper end of the rotating disc support is rotationally provided with a bearing rotating disc, and at least six lower molds are arranged in a circumferential array on the bearing rotating disc; a support rack is arranged outside the rotating disc mechanism, and a distributing mechanism, a lower-pressing forming mechanism, an air-cooling cooling mechanism, a blanking and carrying mechanism, a lower mold cleaning mechanism and a release agent brushing mechanism corresponding to the lower molds are sequentially arranged on the support rack along the circumference of the bearing rotating disc; and the application can realize multi-station sequential and simultaneous processing, thereby improving the processing efficiency.

The invention relates to the technical field of pavement materials, and particularly discloses an all-solid waste asphalt mixture as well as a preparation method and application thereof. The all-solid waste asphalt mixture is prepared from the following raw material components: activated waste rubber powder, waste rubber powder modified emulsified asphalt, a waste asphalt-based pavement material, aggregate, a fiber material and an additive, wherein the aggregate comprises coal gangue powder, waste magnesia carbon brick powder, nut shell powder, coarse aggregate, steel slag powder and fine aggregate; the fiber material comprises activated aramid fiber and waste rubber powder modified glass fiber reinforced plastic fiber; the additive comprises a smoke suppression viscosity reducer and a styrene-butadiene-styrene block copolymer. The all-solid waste asphalt mixture with excellent pavement performance is prepared by utilizing the synergistic effect of all the component raw materials, and the problem that the pavement performance of an asphalt regenerated mixture is poor due to the fact that existing solid waste is poor in compatibility with other components when being applied to the asphalt regenerated mixture is effectively solved.

The invention provides a high-mixing-amount RAP recycled asphalt mixture design method based on a fine separation process, which is characterized in that based on the RAP fine separation process, an RAP material is treated through a grading stripping and high-frequency screening (frequency is greater than or equal to 25Hz) process, so that the grading variation coefficient is less than or equal to 6.59%, and the caking rate is less than or equal to 5.2%; the mass ratio of the coarse material to the fine material of the RAP is controlled to be 10: 2.5-10: 4.5, the reference value of the total mixing amount of the RAP is obtained through the equilibrium design (changing cross point) of an indoor performance test, and then the actual value of the total mixing amount of the RAP is determined through a correction formula. The invention further provides the high-mixing-amount RAP recycled asphalt mixture designed according to the design. According to the design method of the high-doping-amount RAP recycled asphalt mixture and the designed high-doping-amount RAP recycled asphalt mixture, the problem of collaborative optimization of the ratio of coarse and fine materials and the doping amount threshold value can be solved, and collaborative optimization of high doping amount and high performance can be achieved.

The invention discloses a high-performance cold patch asphalt mixture as well as a preparation method and application thereof, belongs to the technical field of asphalt mixture processing, and is used for solving the technical problem that the curing property, the aging resistance and the mechanical property of an asphalt mixture in the prior art need to be further improved. The modified nano-crystalline cellulose aerogel modified asphalt comprises the following components in parts by weight: 90-100 parts of a component A, 60-70 parts of a component B and 50-60 parts of a component C. The modified nano-crystalline cellulose aerogel modified asphalt is prepared by taking matrix asphalt, modified nano-crystalline cellulose aerogel and a diluent as the component A, taking a modified curing agent and alkaline aggregate which can be rapidly cured at room temperature as the component B and taking modified epoxy resin, a photoinitiator and a surfactant as the component C, the curing performance and the aging resistance of the cold patch asphalt mixture are effectively improved, and the mechanical performance of the cold patch asphalt mixture is also improved.

The present invention discloses a modified asphalt mixture, which comprises modified asphalt, aggregate and mineral powder; the control of the passing rate range of the aggregate for each sieve hole is shown in Table 1. By modifying the aggregate gradation, the asphalt mixture has the characteristics of good water tightness, uniform and not easy to segregate, outstanding anti-skid performance, high temperature resistance, long service life, convenient maintenance and low operation cost, and is applicable to the climate with high temperature and heavy rain.

The invention relates to the field of old asphalt regeneration, in particular to an old asphalt mixture regeneration device and a regeneration process thereof.The old asphalt mixture regeneration device comprises a storage device used for storing materials, a fluidized bed drying system, a roller drying system, a stirring main machine and a dust removal system; the fluidized bed drying system is used for drying and metering small-particle-size asphaltic sand and comprises a feeding hopper, a fluidized bed, a first metering device and a first smoke exhaust device. The material storage device comprises a stock bin, a material overturning mechanism arranged in the middle of the stock bin and used for lifting and overturning materials and a discharging mechanism arranged at the lower end of the stock bin, an air inlet and an air outlet are formed in the two opposite side walls of the stock bin respectively, a feeding port and a discharging port are formed in the stock bin, and the discharging port is communicated with the discharging mechanism; and hot air circulating systems are arranged on the air inlet and the air outlet. The technical problem that asphaltic sand is easy to accumulate and adhere is solved.

The utility model discloses an asphalt mixture rut sample forming machine which comprises a carrying box body, a supporting frame fixedly connected to the carrying box body, a controller fixedly connected to the front end of the supporting frame, a test trolley located at the upper end of the carrying box body and located below the supporting frame, and a sample disc detachably connected to the test trolley. The upper end of the supporting frame is fixedly connected with an air cylinder. The output end of the air cylinder is detachably connected with a connecting frame. The lower end of the connecting frame is detachably connected with a grinding wheel; and the connecting frame is rotationally connected with a cleaning part for cleaning the lower surface of the runner wheel. Compared with the prior art, the cleaning device has the advantages that by arranging the cleaning scraper, after the rocking rod is rocked, the cleaning scraper moves along the radian direction of the lower surface of the runner wheel under the support of the connecting rod, so that the asphalt mixture adhered to the lower surface of the runner wheel is cleaned, and a heat insulation material is wound on the rocking rod, so that a worker is prevented from being scalded; the cleaning efficiency is improved, and the test completion time is shortened.

The invention relates to the technical field of road material engineering, in particular to an asphalt mixture gradation optimization method and device, electronic equipment and a storage medium. According to the gross volume relative density, the apparent relative density and the tamping density of each grade of aggregate, the actually measured stacking density of each grade of aggregate is calculated; on the premise of ensuring that the pre-estimated void ratio, the pre-estimated asphalt saturation and the pre-estimated mineral aggregate void ratio meet the target requirements, in the standard grading range and the parameter value range of the Bailey method, the maximum pre-estimated stacking density, the maximum pre-estimated mineral aggregate void ratio and the minimum pre-estimated asphalt-aggregate ratio are used as target functions, grading iterative optimization is carried out by utilizing a multi-target particle swarm algorithm, and the maximum pre-estimated stacking density, the maximum pre-estimated mineral aggregate void ratio and the minimum pre-estimated asphalt-aggregate ratio are obtained. The Pareto solution of the optimized gradation is obtained; analyzing the Pareto solution of the optimized gradation, and selecting a plurality of groups of optimized gradation according to the principle of minimum asphalt-aggregate ratio. According to the method, the economical efficiency and the success rate of grading optimization of the asphalt mixture are improved.

The invention discloses a high-modulus recycled asphalt mixture and a preparation method and application thereof, and relates to the technical field of road structure materials, the high-modulus recycled asphalt mixture comprises 50%-55% of RAP, 4.7%-5.2% of SBS modified asphalt, 6%-9% of a warm mixing regenerant, 0.1%-0.2% of a high-modulus agent, 35%-45% of mineral aggregate and 1%-2% of mineral powder, and the total mass is 100%. During preparation, the SBS modified asphalt and the warm mixing regenerant are prepared into composite asphalt, and then the composite asphalt is sequentially mixed with the heated RAP, the mineral aggregate, the high-modulus agent, the mineral powder and the like; compared with the prior art, the utilization rate of the RAP material is increased, the high modulus characteristic is realized, the production process is simplified, the performance index is excellent, the low-carbon green development requirement is met, and the method has great significance in resource utilization and performance improvement in the field of road engineering.

The invention relates to the technical field of asphalt mixtures, and particularly discloses a pavement asphalt mixture applied to an alpine region and a preparation method of the pavement asphalt mixture. According to the invention, the rubber powder modified asphalt is selected, the type of the coarse aggregate is limited to be steel slag, and the diatomite and the polyester fiber are also added as additives. Under the synergistic effect of the rubber powder modified asphalt, the steel slag and the additive, the asphalt mixture disclosed by the invention can overcome cracking stress generated under a low-temperature condition, so that low-temperature damage is effectively resisted, the low-temperature crack resistance of the asphalt mixture is improved, and the application requirements of a pavement structure in an alpine region can be fully met.