Mechanical Properties Of Asphalt Mixtures Research Articles

A model predicting mechanical properties of asphalt mixtures considering void ratio and loading conditions

The void ratio is an essential parameter in asphalt mixture design, which significantly affects asphalt mixtures' mechanical properties and road performance. The prediction model for mechanical properties will be established based on the Computed tomography (CT) scanning, strength, and fatigue test results in this research to reveal the relationship between the asphalt mixtures' mechanical properties and void ratio. Firstly, the voids' transverse and longitudinal distribution characteristics in asphalt mixtures of different gradations were investigated based on CT scanning. Then, the influences of void ratio, loading rates on the strength, and the impacts of void ratio and stress levels on the fatigue life were investigated by conducting indirect tensile tests. Finally, the mechanical properties prediction model was established for void ratio and loading conditions. Further, the feasibility of the model is verified in conjunction with existing research results. The results show that the void ratio calculated based on CT scanning is about 1.15 times the measured void ratio in the water weight method. The number of voids was uniformly distributed in the range of 15 mm∼50 mm in height and 10 mm∼40 mm in radius of the specimen. The asphalt mixtures' strength decreases with increasing void ratio and increases with increasing loading rate. The asphalt mixtures' fatigue life declines with increasing void ratio and stress level. The correlation coefficients of the established strength and fatigue prediction models were 0.963 and 0.976, respectively. The relative error between the measured strength, fatigue life, and predicted results is about 10.75% and 11.27%, respectively. This research provides a basis for designing high-performance asphalt mixtures by establishing the relationship between asphalt mixtures' microscopic and mechanical characteristics.

Characterization on the mesostructural properties of asphalt mixtures based on meso-element equivalence method

The randomness and variation of material composition at the meso-scale lead to some limitations in the application of asphalt mixture. When all features are taken into account, the computational effort increases significantly. Therefore, the relationship can be established using the meso-element equivalence method (MEEM). In this paper, the effects of aggregate-asphalt interface, initial void defects and material damage were introduced and MEEM of asphalt mixture was established based on industrial computed tomography (ICT) and finite element method (FEM). The rationality of the model was verified by laboratory performance tests, and the effects of aggregate type, mixture gradation and mesostructural parameters on the mechanical response of MEEM were compared and analyzed. The results showed that the MEEM model captures the mechanical behavior of asphalt mixtures well, the input of visco-elastic material parameters is an important step of MEEM simulation accuracy. The aggregate type, the discrete degree of the skeleton structure and the distribution characteristics of mesostructural parameters are important factors affecting the mechanical properties of asphalt mixture in MEEM.

Causes of Asphalt Pavement Blistering: A Review

No theoretical model effectively explains the blistering process, which provokes functional distress in asphalt pavements worldwide. This study focuses on the possible causes of blistering, the physical processes that drive blistering, the role of asphalt properties, and the uncertainties and gaps in the current knowledge. This paper analyzes peer-reviewed studies on pavement blistering published between 1959 and 2022 retrieved in a systematic literature review to justify and model this distress observed on sidewalks, airports, and bridges. According to the scientific literature, high surface temperatures due to solar radiation are the common factor responsible for uplifting, but several causal mechanisms have been investigated. Indeed, chemical reactions, evolutionary materials, thermal buckling, and physical reactions are the generally recognized causes. Their effects on pavement smoothness vary according to the various interdependent geometrical, physical, and mechanical properties of asphalt mixtures and the boundary conditions. Both the mix design and construction processes can hinder the blistering process that occurs during daytime hours of the hot season, right after the work is finished or a few years later. Further research should identify measures to prevent bulges whose management after uplift is difficult but necessary to avoid safety and functional issues.

Evaluating the fracture characterization of asphalt mixtures under freeze-thaw damage based on full-field measurements

Understanding the fracture characterization of asphalt mixtures is important to improve pavement performance in seasonal frozen regions. It is necessary to analyze the cracking characteristics and mechanism of asphalt mixtures under the action of freeze–thaw damage. The semi-circular bending (SCB) crack test combined with digital image correlation (DIC) was conducted to evaluate the fracture characterization of asphalt mixtures under freeze–thaw cycles. The X-ray scanning measurement, bending beam rheology (BBR) test, oblique shear test, the generalized Maxwell model (GM), and the cohesive zone model (CZM) were utilized to reconstruct the 3D heterogeneous finite element (FE) model and reveal the damage mechanism. The results indicated that the freeze–thaw cycles negatively affected the cracking resistance of asphalt mixtures. After 20 freeze–thaw cycles, the fracture energy, stiffness, flexibility index, stress intensity factor, and crack evolution rate decreased by 22.96%, 19.53%, 63.93%, 63.93%, and 61.15%, respectively. The FE model was able to reflect the mechanical properties of asphalt mixtures with different numbers of freeze–thaw cycles well. The FE model can well reflect the mechanical properties of asphalt mixtures under different numbers of freeze–thaw cycles. It also reveals the deterioration of asphalt mortar properties and interfacial adhesion under the action of freeze–thaw damage, which leads to the reduction of internal stress transfer efficiency and attenuation of cracking resistance of asphalt mixtures. This study contributed to the damage mechanism evaluation of asphalt mixtures in seasonal frozen regions and may help with pavement design, construction, and maintenance.

Aggregate gradation effect on the mechanical properties of asphalt mixtures

The issue of road deterioration in Mosul, Iraq, has become a matter of concern for local communities. The instability of road surfaces under the stress of vehicular traffic necessitates significant intervention to mitigate and manage this problem. This study has developed an asphalt mixture by following the Bailey method for aggregate gradation. The impact of aggregate gradation on the mechanical properties of the asphalt mixture was thoroughly analysed. Additionally, two separate mixtures were conducted using the conventional Marshall method to assess indirect tensile strength, Marshall properties, and susceptibility to moisture damage. The primary objective of this research is to design an aggregate structure that acts as a robust unit capable of withstanding heavy loads, repeated stresses, and high temperatures. The findings of the study indicate that the asphalt mixture created using the Bailey method exhibited superior stability with values of 13.6 kN, compared to the two traditional mixtures (11.8 kN, 9.2 kN), and. However, it is worth noting that the flow values also indicated a relative preference for the Bailey method, with values of and 3.1 mm, compared with 3.85 mm and 3.2 mm of the traditional mixtures. The results of Tensile strength ratio further corroborated the efficacy of Bailey’s technique, with outcomes of 85.1 %, thus enhancing the applicability of this method. This observation is attributed to the concept of granular interlocking, which forms the foundation of the Bailey method.

Enhanced stability of a three-dimensional graphene nanosheets networks modified asphalt mixture

To date, several concepts have been developed to enhance the mechanical and service life of asphalt pavements. Additives such as graphene, carbon nanotubes, carbon fibers and carbon black are used in the hot mix asphalt (HMA) or the asphalt binder (i.e., bitumen) for higher resistance to permanent deformations such as rutting, and transverse thermal cracking due to increased traffic volumes, vehicle mass and axle loads. In this study, graphene nanosheets (GNs) were used as potential modifier of bitumen binder in the HMA. The objective of this work is to investigate the impact of GNs modified bitumen on the Marshall stability and flow of the asphalt mixture using laboratory-compacted samples. The X-ray diffraction (XRD) study revealed a diffraction peak of GNs (002) at 2θ =26.5° along the bitumen’s γ-band and 10-band, which confirm a successful dispersion of GNs into bitumen binder. Furthermore, morphological analysis showed formation of a three dimensional (3d) interconnected networks of GNs between the bitumen micro-structures which could act as bridges for increased flexural strength of the binder. The Marshall stability and flow test results indicate that the mechanical properties of asphalt mixture were influenced by the addition of GNs to the bitumen binder. At 5% by weight of GNs modified bitumen (GNs-B), the compacted hot-mix Asphalt sample showed a higher Marshall stability of 11.7 kN recording 13.6% enhancement in comparison with the asphalt mixture with pure bitumen (P-B). In addition, when GNs-B was used, a lower flow of 1.4 mm was recorded which is desirable to prevent rutting and other forms of failure in asphalt pavements. This study underlines that adding GNs into asphalt binders such as bitumen could play a key role in enhancing the performance of asphalt pavements, which in turn extends their service life and saves maintenance expenses.

Laboratory investigation on electrical and mechanical properties of asphalt mixtures for potential snow-melting and deicing pavements

This study aims to develop electrically conductive asphalt (ECA) mixtures utilizing carbon fiber and/or graphite for potential snow/ice-melting pavements without compromising the mechanical properties. The results showed that an electrical resistivity of 0.7–2.7 Ω·m could be potentially used as the design resistivity of ECA mixtures. 6 mm was the optimum length of carbon fiber for improving electrical conductivity. The ECA mixtures had a comparable or higher Marshall stiffness and indirect tensile strength than the control mixture. Adding carbon fiber alone significantly improved the cracking resistance of single-phase ECA mixtures, while the cracking performance of two-phase ECA mixtures was highly affected by the combinations of carbon fiber and graphite. Four ECA mixtures could meet the design resistivity requirement, while only one single-phase ECA mixture containing 6 vol% (by volume of binder) carbon fiber and one two-phase ECA mixture made with 3 vol% carbon fiber and 15 vol% graphite did not impair the cracking resistance.

Engineering properties-based parameters used for moisture damage evaluation of asphalt mixtures: a review

Moisture-induced damage has been known as a major premature distresses in asphalt pavement. Numerous review papers have been made to provide the progression in study on moisture damage of asphalt pavement. However, mechanical properties of asphalt mixtures used as a parameter for moisture susceptibility evaluation were not reviewed in detail. To make the review of moisture-induced damage in asphalt pavement more comprehensive, this paper reviews research studies on moisture damage of asphalt pavement in view of mechanical properties as a parameter during the past 50 years. These parameters include tensile strength ratio (TSR), cohesion ratio (CR), dynamic modulus ratio (DMR), resilient modulus ratio (RMR), and shear strength ratio (SSR). TSR and CR are only relevant at bottom of asphalt concrete (AC), while SSR can be used to describe moisture damage at different AC depths. DMR and RMR are concentrated on the impact of moisture damage via performance characteristics of asphalt mixtures.

Study on the shear strength of asphalt mixture by discrete element modeling with coarse aggregate morphology

High shear strength is crucial for asphalt pavements to resist permanent deformation at high temperatures, which is largely determined by the skeletal structure of coarse aggregates. In this study, four size ranges of polyhedral coarse aggregate clumps were built to simulate the morphology and dimensional characteristics of coarse aggregate. Subsequently, virtual triaxial shear tests were simulated using discrete element models. Three gradation types were analyzed to study the effects of aggregate structure, granularity composition, and coarse aggregate modulus on the shear strength of asphalt mixtures. The results show that it is feasible to obtain accurate morphological features of coarse aggregates by controlling the minimum diameter of the filled spheres in a polyhedral coarse aggregate box when constructing a discrete element model. The virtual triaxial shear test model developed in this study can be effectively utilized to simulate the shear mechanical properties of asphalt mixtures under various confining pressures. The numerical simulation results indicate that the cohesion of asphalt mixture AC-13 is the best, while the internal friction angle and shear strength of SMA-13 are the highest. The ranking of factors that affect the cohesion and internal friction can be summarized as: aggregate structure ≫ coarse aggregate modulus > granularity composition, while the order of factors that affect the shear strength is: aggregate structure ≫ granularity composition > coarse aggregate modulus. This indicates that the aggregate structure is crucial for the high-temperature performance of asphalt mixtures. This study addressed the issue of high variability in laboratory test results for macroscopic properties of asphalt mixtures and analyzed the skeleton role of coarse aggregate in asphalt mixtures from a mesoscopic perspective. The findings parameters for explaining the strength mechanism. The discrete element models also facilitate the optimization of asphalt mix design with reduced labor and time consumption on laboratory testing.

Evaluation of the impact of various stabilizing additives, including hydrolysis lignin, on the basic physical and operational parameters of rubble-mastic asphalt concrete mixtures

The paper considers the use of various stabilizing additives, including hydrolysis lignin, in rubble-mastic asphalt mixtures. Laboratory tests were conducted using calibrated measuring instruments and certified laboratory equipment, along with officially recognized methods for testing the physical and mechanical properties of asphalt mixtures. Based on the data obtained, a comparative analysis of the effect of stabilizing additives on the main physical and operational indicators of rubblemastic asphalt concrete mixtures was carried out. It was established that the use of different stabilizing additives in rubble-mastic asphalt concrete mixtures did not lead to significant changes in the basic physical and operational indicators, except for the binder flowing indicator, i.e., the ability of rubblemastic asphalt concrete mixtures to retain bitumen. The laboratory studies also confirmed the possibility of using a stabilizing additive – hydrolysis lignin – without compromising the physical and operational characteristics of the mixture according to GOST R 58406.1-2020. A slight increase in water resistance was observed when hydrolysis lignin was added, largely due to its ability to modify road bitumen and its high content in the mixture compared to other additives.

Effect of recycled additives on pure mode I fracture resistance and moisture susceptibility of hot mix asphalt (HMA): An experimental study using semicircular bending (SCB) and indirect tensile strength (ITS) tests

Moisture susceptibility and cracking are considered as two major causes of distress in asphalt pavement, which are developed and expanded under environmental factors such as Freeze-Thaw Cycles (FTC) and traffic loading. These causes of distress may be controlled by improving two factors of bituminous phase cohesion and adhesion between aggregates and bitumen. This article was aimed to study the rheological properties of bitumen, such as rotational viscosity, as well as the mechanical properties of asphalt mixture, such as moisture susceptibility, fracture resistance, and fracture brittleness, by using two additives, carbon black and hydrocarbon, which were obtained from the pyrolysis recycling of hospital waste caused by Covid-19. In this regard, a total of 8 mixtures were made, including a mix without any additive, three mixes of 1.25, 2, and 2.75 % hydrocarbon, three mixes of 6, 12, and 18 % carbon black, and a mix of 2.75 % hydrocarbon + 18 % carbon black. In order to determine the effect of FTC on the asphalt samples and to adapt the laboratory conditions to the road conditions, 1 and 3 cycles of Freeze-Thaw Damage (FTD) were applied, respectively, indicating 4 and 12 years of pavement distress. The results showed that the addition of different percentages of carbon black and hydrocarbons (separately and together) through improving bituminous phase cohesion and adhesion between aggregates and bitumen increased the samples resistance to the moisture susceptibility. It was also found that fracture energy (GF) and fracture toughness (KIC) of all mixes improved compared to the base sample. At last, the results of brittleness indicators revealed that all mixes containing 6, 12, and 18 % carbon black and 1.25, 2, and 2.75 % hydrocarbon had a more flexible behavior than the base mix under 1 cycle of FTD; while the mixes containing 18 % carbon black and 2.75 % hydrocarbon were just flexible under 3 cycles of FTD. Accordingly, it can be concluded that a mix containing 2.75 % hydrocarbon + 18 % carbon black had the best results in terms of viscosity, moisture susceptibility, and fracture resistance (under 1 and 3 FTD cycles).

Editorial: Recent advances in testing and modeling of performance-related mechanical properties of asphalt mixtures

Editorial: Recent advances in testing and modeling of performance-related mechanical properties of asphalt mixtures

Decay Characteristics of Mechanical Properties of Asphalt Mixtures under Sizeable Wet Temperature Cycle

Asphalt mixtures will inevitably be affected by rainwater and the effect of the wet temperature cycle during a pavement’s life span. Especially in coastal areas such as Guangdong and Hainan in China, asphalt pavement is particularly susceptible to the sizeable wet temperature cycle formed by the high temperature and sudden temperature drop of rainstorms in summer. For this study, we used a homemade sizeable wet temperature cycle environment simulation device to analyze the decay characteristics and the mechanical properties of asphalt pavements in this environment; modified bending and tensile strength and shear strength tests were used to study the decay patterns of shear strength, bending, and tensile strength, and the stiffness modulus of asphalt mixtures with different air voids and different pavement depths under the action of a sizeable wet temperature cycle. In addition, the Grey correlation method was used to analyze the significance of each influencing factor on the decay of mechanical properties, and mathematical fitting was used to establish the prediction equation of the mechanical properties of asphalt mixtures. The results show that with the increase in the number of sizeable wet temperature cycles, the asphalt mixture’s shear strength, flexural tensile strength, and flexural tensile modulus decrease, the degree of decay increases, and the rate of decay gradually slows down. In the case of the same number of sizeable wet temperature cycles, the degree of decay of the asphalt mixtures gradually decreases with increasing depth or decreasing void ratio. After 100 sizeable wet temperature cycles, the maximum values of the decay of shear strength, modulus of strength, and flexural tensile strength were 22.30%, 23.29%, and 32.01%. The importance of the influence of each factor on the decay of the mechanical properties is as follows: the number of sizeable wet temperature cycles > void rate > depth. The prediction equations of the established mechanical properties have a good prediction effect, and the correlation between predicted values and actual values can be up to 0.925. The prediction equations can effectively predict the mechanical properties of asphalt mixtures with different air voids and depths under the action of sizeable wet temperature cycles.

IMPACT OF DEICING SALT ON THE PERFORMANCE OF ASPHALT MIXTURES IN NORTHWEST CHINA: AN INVESTIGATION INTO MECHANICAL PROPERTIES AND INFLUENTIAL FACTORS

Currently, the primary form of high-grade highways is constituted by asphalt concrete pavement. Winter conditions often result in ice and snow accumulation on these pavements, precipitating severe traffic incidents. Statistically, around 15%-30% of such incidents are directly linked to icy and snowy conditions. Hence, when roads are laden with ice and snow, the most cost-effective and efficient countermeasure remains the dispersal of deicing salt onto the road surface. Particularly in China's northwestern region, which experiences low precipitation and consistent droughts, the deicing salts applied during winter aren't diluted or transported away by water flow. Consequently, the soil surrounding the roads retains a higher concentration of deicing salts than other regions, leading to a pronounced impact on the pavement's service life. This investigation aims to experimentally emulate the impact of this high-salt environment on the mechanical properties of asphalt mixtures, followed by an analysis of the crucial factors that influence the asphalt mixtures' durability. The current study employs measures such as high-temperature rut testing, Marshall water immersion testing, and freeze-thaw splitting testing to investigate the damage patterns of mechanical properties in asphalt mixtures under varying grading, diverse deicing salt solutions, and differing frequencies of dry-wet cycles. In addition, the study employs grey correlation entropy analysis to ascertain the interdependence among factors influencing the performance of asphalt mixtures. The findings reveal that after undergoing 0, 5, 10, 15, 20, 25, and 30 dry-wet cycles in solutions of 20% industrial salt (NaCl), 15% urea (CH4N2O), and 20% anhydrous ethanol (CH2CH3OH), both the high-temperature stability and water stability of asphalt mixtures with AC-13 and AC-16 gradings displayed varying levels of decline. Overall, an enhancement in the fine aggregate percentage in asphalt mixtures can augment the asphalt concrete's resistance to deicing salt erosion. As per the grey correlation entropy analysis, gradation variances exerted the most significant impact on diverse mechanical properties, followed by the type of deicing salt solution, with the least significant impact attributed to the frequency of dry-wet cycles. Thus, judicious selection of road materials and structural design can effectively counter the erosive action of deicing salts, thereby enhancing the service life of the road surface.

Influence of Deicer on Water Stability of Asphalt Mixture under Freeze–Thaw Cycle

In seasonal frozen soil areas, the repeated freeze–thaw cycle of internal moisture in asphalt mixture in winter and spring will accelerate the peeling of asphalt film and aggravate the water damage of asphalt pavement. It is of great significance to carry out the attenuation law of mechanical properties of asphalt mixture under freeze–thaw cycles to prevent and reduce the economic losses caused by water damage to asphalt pavement. This study will investigate the impact of deicer application on the water stability of asphalt mixtures within the climatic conditions prevalent in Northwest China. Specifically, freeze–thaw cycle tests were administered to two types of dense-graded asphalt mixtures under three distinct deicer solutions and three disparate low-temperature environments. The Marshall water immersion test and freeze–thaw splitting test were employed to evaluate the water stability of asphalt mixtures subject to multiple factors, and the relative importance of each factor was statistically analyzed using the acquired data. Results demonstrated that AC-13 and AC-16 asphalt mixtures (AC is asphalt-concrete, which is asphalt concrete, and 13 or 16 represents the maximum particle size of aggregate (13 mm or 16 mm)), saturated in 15% CH4N2O, 20% NaCl, and 20% CH2CH3OH solutions, underwent a varying number of freezing–thawing cycles (0, 5, 10, 15, 20, 25, and 30) at temperatures of −5 °C, −15 °C, and −25 °C, respectively, displayed a discernible decline in their residual stability MS0 and freeze–thaw splitting tensile strength ratio TSR. This decline was particularly marked when temperatures dropped below the solution’s freezing point. Disregarding the fixed factors of weather variation (different low-temperature environments) and road service duration (number of freezing–thawing cycles), the aggregate grading imposed a more pronounced influence on asphalt mixture water stability than the presence of deicers.

Investigation of Self-healing and Mechanical Properties of Asphalt Mixtures Prepared with SBS and Waste Metal

Investigation of Self-healing and Mechanical Properties of Asphalt Mixtures Prepared with SBS and Waste Metal

Reuse of plastic waste in asphalt mixtures with residual porous aggregates

The reuse of plastic and poor-quality residual aggregates in the manufacture of bituminous mixtures for paving could contribute to reclaim significant quantities in the pavement construction industry since certain polymers can enhance the mixture properties. This study investigates the potential use of waste from recycled polyethylene terephthalate (PET) in asphalt mixtures with extremely-vesiculated residual aggregates, which are also rejected in quarry production. In this research, the physical, compaction, and mechanical properties of asphalt mixtures with these marginal aggregates, different binder consistencies and PET contents replacing part of the aggregate are studied. The results indicate that limited proportions of waste PET (up to 1 %) are compatible with extremely porous aggregates and can improve certain mixture engineering properties, such as the resistance to water action and to rutting. These mixtures meet specifications for base courses and even for pavement surfaces under limited heavy-truck traffic, while contributing to the sustainability of asphalt pavements by reducing the extractive demand of natural resources and replacing them with waste materials.

Analysis of Factors Influencing the Modulus of Hot-Recycled Asphalt Mixture with High RAP.

Generally, the dynamic modulus and bending stiffness modulus are used to evaluate the mechanical properties of asphalt mixture, and they are also used as basic parameters for asphalt mixture design. Therefore, a study was conducted on changes in the dynamic modulus and bending stiffness modulus of hot-recycled asphalt mixture with high levels of reclaimed asphalt pavement (RAP) under the influence of different factors: dosage of regenerant, curing temperature, and curing time. The performance of reclaimed asphalt pavement (RAP) was first evaluated. Then, the hot-recycled asphalt mixture was adjusted and designed in order to conduct modulus experiments, composed of the dynamic modulus test and three-point bending test. Finally, the influencing factors were not only qualitatively but also quantitatively analyzed to clarify the change laws of the mechanical parameters of hot-recycled asphalt mixture. The results showed that the modulus of the recycled asphalt mixture first decreased, then increased, and then decreased with increasing dosage of regenerant. As the curing time or temperature increased, the modulus first decreased and then increased. In terms of the dynamic modulus of the hot-recycled asphalt mixture, the curing time had the greatest impact, followed by dosage of the regenerant and curing temperature. For bending stiffness modulus, the influence of dosage of the regenerant was the greatest, followed by curing time and curing temperature. For the bending stiffness modulus of hot-recycled asphalt mixture, the curing conditions had a greater influence compared with the dynamic modulus.

Effect of Specimen Fabrication Variables on the Measured Mechanical Properties of Asphalt Mixtures Tested in the Asphalt Mixture Performance Tester (AMPT)

Abstract The scope of this research involves the evaluation of the effects of specimen preparation variables—mixing temperature, binder time at mixing temperature, mixer type, mixing time, loose mix conditioning temperature, loose mix conditioning depth, loose mix stirring, mold loading, placement in mold, additional time at compaction temperature before loading in mold, gyratory specimen height, and test specimen air voids—on tests such as the Dynamic Modulus and Flow Number conducted using the Asphalt Mixture Performance Tester (AMPT). The initial testing program to evaluate the precision of the Dynamic Modulus and Flow Number tests (described in National Cooperative Highway Research Program Report 702) indicated that “specimen fabrication is a major component of the between-laboratory variability” for both tests. The expected outcome of this study was that AMPT users—Federal Highway Administration (FHWA), state user agencies, and industry—understand the importance of proper specimen preparation and the effect of specimen preparation variables on the results obtained from the AMPT Dynamic Modulus and Flow Number tests. The use of AMPT Dynamic Modulus at 20°C is the most sensitive portion of the modulus-time curve and can provide a general idea of sample preparation impact on other mixture tests. This information comes at critical timing as the United States begins to implement performance-engineered mixture designs, balanced mixture designs, and performance-based pay factors. Based on the findings of the study, recommendations may be made regarding changes to specimen preparation procedures, which are expected to produce more reproducible test results.

Mechanical Analysis Model of Asphalt Concrete Random Particles Based on Mix Ratio

The strength and other mechanical properties of asphalt mixtures are directly affected by their size, shape, distribution, and interaction of asphalt concrete particles. Mesoscale performance is important for studying the structure of asphalt mixtures. The random particle model of asphalt concrete is one of the important topics in mesoscale research. On the basis of existing research at home and abroad, based on the asphalt mixture mix ratio, this paper further improves the algorithm of random particle generation, optimizes the algorithm of single-particle generation, ensures that the shape of particles at the time of generation conforms to the engineering practice, and forms a random particle reserve library, in order to improve the efficiency of particle delivery, facilitate the model mesh division, and provide a basis for the smooth progress of mechanical analysis.