24 results about "Dynamic modulus" patented technology

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 utility model belongs to the technical field of asphalt mixtures, and particularly relates to an asphalt mixture tensile dynamic modulus testing device which comprises a tensile testing machine body, a fixing block connected to the surface of the front end of the tensile testing machine body, a rotating shaft rotationally connected to the side wall of the fixing block, a rotating plate rotationally connected to the surface of the rotating shaft, and a limiting block arranged on the surface of the other side of the rotating plate. The surface of the limiting block is connected to the limiting frame in a clamped mode, the inner wall of the rotating plate is connected with a first heat insulation plate in an embedded mode, the top of the first heat insulation plate abuts against the bottom surface of a second heat insulation plate, the surface of the second heat insulation plate is connected to the inner wall of the rotating plate in an embedded mode, the rear side surface of the tensile testing machine body is connected with a side plate, and the inner wall of the side plate is connected with a heat insulation cover in an inserted mode. The thermal insulation plate and the thermal insulation cover mounted on the front side and the rear side of the tensile testing machine body are used for thermal insulation and heat preservation of a detection environment in the tensile testing machine body, so that the influence of the temperature of an external environment on asphalt fixed on the tensile testing machine body is avoided, and the accuracy of an asphalt tensile result is ensured.

The application relates to the road maintenance technical field, in particular to a road fatigue performance evaluation method based on dynamic modulus; the road fatigue performance evaluation method based on dynamic modulus comprises the following steps: constructing a correlation curve for mapping the relationship between dynamic modulus representing road rigidity and the fatigue life of the road; setting a key life threshold for judging the fatigue performance; determining a limit modulus boundary in the correlation curve according to the key life threshold; obtaining a core sample of a service road; measuring the actual measured dynamic modulus of the core sample under a preset evaluation frequency; and judging the road state based on the positional relationship between the actual measured dynamic modulus and the limit modulus boundary. The application has the effect of improving the timeliness of the fatigue performance evaluation of the recycled asphalt mixture.

This invention relates to the field of tire manufacturing technology, and more particularly to a low-heat-generating, high-stability crown belt rubber composition, a mixing method, and a tire. Based on 100 parts by weight of the rubber components, it includes natural rubber, first and second non-oil-extended polystyrene-butadiene rubber (BF2055H / L), and is supplemented with highly dispersed silica, carbon black, silane coupling agents, and α-methylstyrene resin, among other additives. BF2055H / L has a 20% styrene content, 55% vinyl content, and a bimodal molecular weight distribution, synergistically improving the dynamic modulus distribution of the rubber and the uniformity of filler dispersion. Optimized mixing processes achieve efficient reaction and uniform distribution of SiO2 with the rubber. Experiments have shown that, without sacrificing hardness and handling performance, the bimodal non-oil-extended SSBR is used as the core to solve the contradiction between heat generation, deformation, and processing; natural rubber ensures adhesion and elasticity; and medium-structure carbon black + silica balances reinforcement and heat generation. This achieves a comprehensive performance breakthrough in low heat generation, low deformation, high support, high durability, and environmentally friendly manufacturing.

The application provides a method for determining the "elastic-skeleton-void" structure of pavement mixture, and belongs to the technical field of pavement materials.The application creatively proposes an "elastic-skeleton-void" structure form aiming at the special material composition of the super-elastic porous mixture, and the structure is the fundamental reason for enabling the super-elastic porous pavement to have the composite functions of noise reduction, drainage, self-stress deicing and the like.Meanwhile, in combination with macroscopic physical and mechanical tests, mesoscopic discrete element simulation and digital image processing methods, and based on the uniaxial compression dynamic modulus of the mixture, the void ratio, the contact number of rubber particles and coarse aggregates, the internal force chain structure composition form and the contact force of the mixture, a method for determining the "elastic-skeleton-void" structure is provided, which is used for determining the skeleton composition structure of the mixture.

This invention provides a dynamic modulus testing system, method, and prediction method for asphalt mixtures, belonging to the technical field of asphalt material testing. It includes a test chamber for placing multiple asphalt mixture specimens; a strain acquisition component for acquiring the strain of the specimens placed in the test chamber due to load; a temperature acquisition component for acquiring the temperature of the specimens placed in the test chamber; a circulating temperature control device connected to the test chamber for controlling the temperature of the specimens placed in the test chamber, ensuring the dynamic modulus test is performed at a target temperature; and an accelerated loading device including a tire, which accelerates the loading of the specimens placed in the test chamber by adjusting the tire. This invention can simulate the testing of the dynamic modulus of asphalt mixtures under real-world conditions and achieve accurate prediction of the dynamic modulus of asphalt mixtures.

The invention relates to a steel bridge deck pavement sensing analysis system and method based on multi-dimensional data. The method comprises the following steps: testing raw materials to obtain construction retention time and interface parameters so as to guide mixture design, preparing a test piece according to the construction retention time and the interface parameters, and measuring a dynamic modulus main curve, a fatigue damage model and limit strain; establishing a reduced-scale test piece finite element model based on the main curve to predict bending-tensile strain, and performing a fatigue test in combination with limit strain to obtain reduced-scale life; obtaining a key stress range of the steel plate through full-scale model finite element analysis, and formulating an acceleration loading scheme according to the key stress range; loading is executed, multi-source monitoring data are collected, and the full-scale final fatigue life is determined; calibrating a fatigue damage model according to the service life; and finally evaluating the performance of the paving system based on the calibration model, the main curve and the full-scale life. According to the closed-loop verification process from the material to the full scale, the prediction model is iteratively calibrated through multi-scale test data, and the accuracy and reliability of long-term performance evaluation of the steel bridge deck pavement system are remarkably improved.

The invention relates to the technical field of asphalt mixture modulus prediction, and discloses an asphalt mixture multi-scale modulus prediction method and system, and the method comprises the steps: obtaining a three-scale joint data set, determining the design stage weight of each scale data, and outputting a design stage dynamic modulus prediction value through a trained first prediction model. The system corresponds to the method. According to the method, the prediction precision of the design stage is remarkably improved by constructing the three-scale data system, comprehensively capturing the modulus influence factors of the asphalt mixture and combining the dynamic weight distribution mechanism adaptive to the stage; through a cross-stage constraint function driven by data quality, the difference from design to service data quality is quantified, and the problem of performance disjunction of the two is solved. A transfer learning mechanism is constructed through a genetic operator, the dynamic change of data quality distribution is adapted, and the prediction stability and adaptability in the service stage are improved; therefore, full-life-cycle modulus accurate prediction is realized, and scientific support is provided for mixture ratio optimization and pavement maintenance decision making.

The application provides an asphalt mixture pavement compaction degree prediction model construction method and a real-time prediction system, the method regards a vibrating compactor wheel as a dynamic coupling system interacting with pavement materials, adopts a Burgers creep model to simulate deformation of the asphalt mixture, establishes a physical mapping relationship among the asphalt mixture pavement compaction degree, the asphalt mixture creep parameter and the vertical acceleration of the compactor wheel, combines a dynamic modulus test to obtain the creep parameter value, and then obtains the compaction degree prediction model. The application overcomes the randomness and instability of the traditional empirical model, can realize real-time monitoring of the pavement compaction quality in the whole compaction process through the vertical acceleration signal, does not need frequent coring detection, the detection is more timely, can significantly improve the construction efficiency and uniformity, the prediction model has good environmental adaptability and robustness, can predict under different construction temperatures and vibrating compaction work conditions, can predict the pavement compaction degree in real time, and the prediction result is reliable.

The invention relates to the technical field of data processing, in particular to a method for calculating the abrasion loss of tread rubber under a wide-temperature-range complex working condition, which comprises the following steps of: processing each parameter by utilizing dimensionless analysis, and constructing a first dimensionless group and a second dimensionless group so as to eliminate dimensional interference and quantify the synergistic effect of mechanical load and material performance. On the basis of temperature data, parameters of a temperature correction function are fitted through a variable-temperature wear experiment, and the nonlinear attenuation rule of the viscoelasticity of the rubber along with the temperature change is accurately represented. And integrating the dimensionless group, the product of the hardness parameter and the dynamic modulus and the temperature correction function into a thermal and mechanical coupling integral model to realize dynamic coupling and synchronous calculation of the multi-physical field parameters. Finally, the abrasion loss is output through the model, the limitation of parameter decoupling in an existing method is overcome, and prediction precision and model adaptability are remarkably improved.

This invention provides a method for calculating the critical point of fatigue damage in full-thickness asphalt pavement, relating to the field of road engineering technology. The invention first divides the full-thickness asphalt pavement into multiple sub-layers, then obtains its annual temperature field and annual axle load spectrum, determines the temperature model of the full-thickness asphalt pavement and the number of equivalent axle load applications per hour, and combines laboratory test results to obtain the dynamic modulus calculation equations and multi-temperature fatigue equations for each sub-layer. The temperature of each sub-layer is obtained using the full-thickness asphalt pavement temperature model, and the dynamic modulus value of each sub-layer is determined using the dynamic modulus calculation equations. Then, the flexural strain response of each sub-layer is calculated based on its dynamic modulus value, and its fatigue life is calculated using the multi-temperature fatigue equations for each sub-layer. Combined with the number of equivalent axle load applications per hour, the fatigue damage value of each sub-layer is calculated and accumulated to obtain the cumulative fatigue damage of each sub-layer in the full-thickness asphalt pavement, accurately obtaining the critical damage point of the full-thickness asphalt pavement.

This invention relates to the field of tire manufacturing technology, and more particularly to a low-deformation rubber composition for tire buffer layers based on bimodal SSBR, a mixing method, and a tire. Based on 100 parts by weight of the rubber components, it includes natural rubber, first and second non-oil-extended polystyrene-butadiene rubbers (BF2055H / L), polybutadiene rubber, and additives such as highly dispersed silica, carbon black, silane coupling agents, and α-methylstyrene resin. BF2055H / L has a 20% styrene content, 55% vinyl content, and a bimodal molecular weight distribution, synergistically improving the dynamic modulus distribution of the rubber and the uniformity of filler dispersion. The mixing process is optimized to achieve efficient reaction and uniform distribution of SiO2 with the rubber. Experiments have shown that, without sacrificing hardness and handling performance, this composition can achieve tanδ (60℃) ≤0.071, M300 controlled at 6.8-7.2 MPa, and DIN abrasion ≤99 mm. 3 Compression permanent deformation ≤30%, flexural life >2.0×10 5 Its overall performance is significantly better than existing oil-filled buffer layer formulations, and it has excellent fuel efficiency, comfort, and process adaptability.

The application discloses a kind of asphalt pavement structure dynamic modulus sampling method based on measured temperature field, it is related to road engineering technical field.The method of the present application is based on the measured temperature history data of active asphalt pavement structure measured by asphalt pavement long-term performance observation network according to the design scheme of the asphalt pavement structure to be laid, the temperature field history data set is constructed, the temperature field history data set is updated by numbering and reassigning to measured temperature history data, the frequency of the same group temperature history data is counted, the cumulative probability distribution curve is generated, the temperature distribution characteristics inside active asphalt pavement structure are obtained, then temperature data sample is generated using inverse function sampling and regression fitting analysis, the internal temperature field of the asphalt pavement structure to be laid is calculated with dynamic modulus master curve to obtain the dynamic modulus of the asphalt pavement structure to be laid.The present application carries out temperature field sampling based on actual physical conditions, and realizes the accurate restoration of the mechanical characteristics of asphalt pavement structure under complex temperature environment.

The invention relates to the technical field of tire manufacturing, in particular to a low-hysteresis high-durability tire cord fabric rubber composition, a mixing method and a tire. 100 parts by weight of rubber components comprise natural rubber, first and second oil-free solution polymerized styrene-butadiene rubber (BF2055H / L), and auxiliary agents such as carbon black. Wherein BF2055H / L has the content of 20% of styrene and 55% of vinyl and bimodal molecular weight distribution, and the dynamic modulus distribution of the rubber and the dispersion uniformity of the filler are synergistically improved. Experiments prove that on the premise that the hardness and the bearing capacity are not sacrificed, the composition can achieve the comprehensive performance that tan delta (60 DEG C) is smaller than or equal to 0.088, the bonding strength is larger than or equal to 12.2 Nmm <-1 >, the DIN abrasion is smaller than or equal to 114 mm < 3 > and the torque of a rubber master batch section is controlled to be 68-72 N.m, the composition is remarkably superior to an existing oil-filled formula, and the composition has the excellent combustion efficiency, durability and process adaptability.

The invention provides a quantitative evaluation and prediction method and system for pavement-tire vibration noise, and relates to the technical field of pavement material design, and the method comprises the steps: obtaining pavement surface texture data; obtaining viscoelastic characteristic parameters through a dynamic modulus test; constructing a pavement-tire-air coupling finite element model; setting tire rolling working conditions including applied load, rolling speed and contact conditions, executing pavement-tire dynamic simulation, extracting vertical displacement time history data of the tire in the rolling process, and calculating a noise reduction quantitative index representing the pavement noise reduction capability; applying the vertical displacement time history data to the three-dimensional tire model as a forced displacement boundary condition, executing tire-air acoustic simulation, extracting a sound pressure signal of vibration noise, and performing frequency domain processing to obtain a predicted noise level; and evaluating the noise reduction performance of the pavement test piece with different surface textures and viscoelastic characteristic parameters based on the quantitative index and the noise level, and outputting a pavement material composition result with the optimal noise reduction capability.

The application discloses a kind of polymer rheological property prediction method and system based on global optimization, to solve the problems that traditional rheological data exists apparent physical deviation, engineering constitutive parameter step fitting is easy to fall into local optimum and microstructure feature is difficult to quantify.The method first obtains the apparent data of polymer in multiple temperature zones steady shearing and dynamic oscillation;Then, based on Rabinowitsch equation, polynomial differential correction is carried out, and the deviation of pipe wall velocity distribution is eliminated to extract the real physical viscosity;Subsequently, a Cross-WLF three-dimensional space model containing temperature and shear rate is constructed, and Levenberg-Marquardt algorithm is used to perform global nonlinear iterative optimization, and the kinetic and thermodynamic constants are extracted in one step;At the same time, dynamic modulus data is introduced to perform Cox-Merz rule self-consistency verification, and a multi-dimensional diagnostic atlas matrix is constructed.The application breaks the limitation of traditional single-temperature zone fitting, and realizes the automatic extraction of high-precision mold flow simulation parameters and the accurate diagnosis of material microphase separation.

The invention provides a test method and device for an ultrasonic triggering microcapsule asphalt pavement, and the method comprises the steps: carrying out the ultrasonic triggering tests of different frequencies and powers on each pre-test sample, and collecting the ultrasonic echo data of each pre-test sample in each ultrasonic triggering test process; extracting a plurality of trigger data from all the ultrasonic echo data based on the trend characteristics of all the ultrasonic echo data; identifying a triggering point of microcapsule triggering fracture in each triggering data, and determining a triggering lower limit of the microcapsule in the target asphalt pavement based on all the triggering points; performing a fatigue cycle test on each main test sample based on the trigger lower limit, and collecting dynamic modulus data of each main test sample after each round of fatigue cycle; and determining the self-healing rate of the target asphalt pavement according to all dynamic modulus data in the fatigue cycle test. By adopting the scheme of the invention, the adaptive ultrasonic parameters in the test can be set according to the ultrasonic transmission characteristics in different pavements.

The application discloses a simple forming method of a test piece for testing the dynamic resilient modulus of basalt fiber asphalt mixture and a result optimization method, and comprises the following steps: S1, a Marshall compaction dynamic modulus test piece mold is designed and manufactured, the inner diameter of the mold is 101.6mm±0.2mm, the cylindrical metal cylinder is 165mm high, the base plate is 12.7mm thick and has a diameter of about 120.6mm; S2, a multi-stage interface hot fusion forming process, (1) the first stage, base forming, (2) the second stage, heightening forming, (3) the third stage, final forming; the application has the advantages that the interlayer overall stability of the high test piece is effectively guaranteed, and the dynamic modulus test piece can be formed by replacing the rotary compaction method; the minimum stable sample size of the Marshall compaction is proposed, and the result is compared, analyzed and corrected with the result of the rotary compaction, so that the stability and reliability of the Marshall method for testing the dynamic resilient modulus of the asphalt mixture are ensured.

This application relates to the field of pavement maintenance technology, and in particular to a method for evaluating road fatigue performance based on dynamic modulus. The method includes: constructing a correlation curve representing the mapping relationship between the dynamic modulus, which characterizes pavement rigidity, and the fatigue life of the pavement; setting a critical fatigue life threshold for judging fatigue performance; determining the ultimate modulus boundary in the correlation curve based on the critical fatigue life threshold; obtaining core samples of the in-service pavement; measuring the measured dynamic modulus at a preset evaluation frequency; and judging the pavement condition based on the positional relationship between the measured dynamic modulus and the ultimate modulus boundary. This application improves the timeliness of fatigue performance evaluation of recycled asphalt mixtures.

The utility model provides comprehensive testing equipment which is used for testing the dynamic modulus and the damping ratio of a material, a sample container, a vibration excitation device, a load sensor and a displacement sensor are arranged in the comprehensive testing equipment, the sample container is arranged at the bottom of the comprehensive testing equipment, and the vibration excitation device comprises a vibration exciter and a compression assembly. The vibration exciter is arranged at the top of the comprehensive test equipment, and the compression assembly is connected with the vibration exciter, is located above the sample container and moves up and down relative to the test container; the load sensor is in contact with the vibration exciter and is used for measuring the load generated by the vibration exciter, and the displacement sensor is in contact with the compression assembly and is used for measuring the compression amount of the compression assembly. Wherein the sample container is used for placing a to-be-tested material, and the excitation device acts on the to-be-tested material and generates a dynamic load. In the experiment process, the dynamic load signal of the vibration exciter and the compression amount of the compression assembly are collected at the same time, the same to-be-tested material, load data and displacement data can be obtained without repeated experiments, the structure is simple, and practicability is high.

The invention relates to the technical field of tire manufacturing, in particular to a low-heat-generation and high-flex-resistance tire base rubber composition, a mixing method and a tire. 100 parts by weight of rubber components comprise natural rubber, first and second oil-free solution polymerized styrene-butadiene rubber (BF2055H / L), butadiene rubber, and auxiliary agents such as carbon black and a silane coupling agent. Wherein BF2055H / L has the content of 20% of styrene and 55% of vinyl and bimodal molecular weight distribution, and the dynamic modulus distribution of the rubber and the dispersion uniformity of the filler are synergistically improved. Experiments prove that on the premise that the hardness and the bearing capacity are not sacrificed, the composition can achieve the comprehensive performance expression that tan delta (60 DEG C) is smaller than or equal to 0.07, the bonding strength is larger than or equal to 3.6 kN / m, and the flex cracking life reaches 15.2-17.8 thousand times, is obviously superior to an existing oil-filled formula, and has the advantages of excellent combustion efficiency, low heat generation, flex resistance and process adaptability.

The present application relates to the technical field of asphalt pavement structure design, and especially relates to a heavy-load durable asphalt pavement gradient structure and a design method under a multi-field coupling environment, the structure is sequentially stacked from bottom to top as a high modulus base layer, a toughness middle layer and an anti-skid surface layer; the dynamic modulus of the high modulus base layer is greater than or equal to 14,000 MPa, the thickness is 18-25 cm, the fracture energy of the toughness middle layer is greater than or equal to 1.5 kJ / m2, the thickness is 8-12 cm, the structure depth of the anti-skid surface layer is greater than or equal to 0.8 mm, the thickness is 4-6 cm, and the modulus gradient ratio of each layer is (2.8-3.5):(1.4-1.8):1; the present application realizes dynamic analysis of multi-factor synergistic degradation effects such as freeze-thaw cycles, high-temperature rutting and interlayer shear by establishing a simulation model coupling temperature field, humidity field and heavy-load stress field and a freeze-thaw damage factor quantization formula, and greatly improves the performance prediction accuracy under the coupling effect of environment and load.

The application relates to the field of road engineering, in particular to a recycled asphalt mixture dynamic modulus prediction method and system. The method comprises the following steps: obtaining recycled asphalt mixture data of a target road surface, inputting the recycled asphalt mixture data into a corresponding dynamic modulus prediction model, and predicting a dynamic modulus curve of the target road surface. The construction steps of the dynamic modulus prediction model are as follows: first, preparing a plurality of aging multilayer DSR test pieces with different aging times and a plurality of water-damaged multilayer DSR test pieces with different soaking times; then, collecting measured data of the aging multilayer DSR test pieces and the water-damaged multilayer DSR test pieces; then, performing regression analysis on the measured data to obtain an aging prediction function and a water damage prediction function; finally, taking dependent variables of the aging prediction function and / or the water damage prediction function as independent variables affecting the dynamic modulus change, and constructing the dynamic modulus prediction model.

This invention relates to the field of tire manufacturing technology, and more particularly to a low-heat-generating, high-elasticity sidewall rubber composition, a mixing method, and a tire. Based on 100 parts by weight of the rubber components, it includes natural rubber, first and second non-oil-extended polystyrene-butadiene rubbers (BF2055H / L), polybutadiene rubber, and additives such as highly dispersed silica, a small amount of carbon black, silane coupling agents, and α-methylstyrene resin. BF2055H / L has a 20% styrene content, 55% vinyl content, and a bimodal molecular weight distribution, synergistically improving the dynamic modulus distribution of the rubber and the uniformity of filler dispersion. This invention, through the synergistic reinforcement of the bimodal high-vinyl SSBR-NR-BR system and silica / carbon black, significantly reduces sidewall heat generation and rolling energy consumption while maintaining a comfort hardness of 56–58A, thereby improving dynamic strength and flexural fatigue life, thus meeting the comprehensive requirements of electric vehicle tires for long range, lightweight, and high reliability.