11 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 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.

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.

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 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 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.

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.