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This paper introduced a preparation method of microcapsules and tests its technical properties. And the survival behaviour of microcapsules in mixture was studied. Then, The influence of microcapsule dosage, mixture properties and healing environment on the mixture self-healing performance was investigated. Finally, the pavement performance of mixture containing microcapsules was studied. Results showed that the microcapsules possessed a smooth surface, a particle size of 14.3 μm, a core content of 85.39%, a hardness of 0.27 GPa, a Young's modulus of 2.49 GPa and good thermal stability. The survival rates of microcapsules were 81.93% and 72.38% at mixing temperature of 130°C and 160°C. Microcapsule dosage of 6%, dense suspension structure, smaller nominal particle size and porosity, large asphalt content, healing temperature of 40–50°C, the healing time of 12 h and dry environment were beneficial to the self-healing performance of the mixture containing microcapsules. After adding microcapsules, the water stability of mixture will decrease, but the high-temperature performance, low-temperature performance and water stability meet the needs of road use. [ABSTRACT FROM AUTHOR]

• The optimal design for the skid resistance was achieved based on the MLS11. • The prediction models for the macro and micro - structure were constructed. • The error between the prediction models and the measured values were within 5%. • The attenuation rate |A|≤2.15 was used as design standard for the skid resistance. To achieve the optimal design and accurate prediction for the long-term skid resistance performance of asphalt pavement, the skid resistance and its evolution trend prediction models of different asphalt mixtures were studied based on the accelerated pavement test using a small accelerated loading device (MLS11). First, three oil-stone ratios, three gradations and four types of coarse aggregates were prepared for different types of asphalt mixes. Second, the long-term skid resistance degradation characteristics and its influencing factors of different asphalt mixtures were studied based on the indoor accelerated pavement test using MLS11. Next, the macro-structure and micro-structure for the evolution prediction models of asphalt pavement were constructed and validated based on the combination of the numerical model and test section. Finally, the design standard and evaluation indexes for skid resistance of high-grade asphalt pavements under heavy traffic conditions were proposed. The results show that dense graded asphalt mixes with a smaller oil-stone ratio have better skid resistance, the type of gradation has less influence on its skid resistance, and the mixture consisting of aggregates with a richer mineral composition type and large difference in mineral hardness has better durability of skid resistance. In addition, the prediction models for the macro-structure and the micro-structure were established, respectively, and the errors of MTD and BPN measured in the test section were controlled within 4% and 5% of the theoretical values. The attenuation rate |A|≤2.15 is proposed as the design criterion for the skid resistance of asphalt pavements. [ABSTRACT FROM AUTHOR]

• The parameter which can represent the texture distribution and range is derived. • The sensitivity and stability of the L TX ,1-31.5 and the MPD are verified. • The surface texture of asphalt pavement is polished by MLS11. • The evolution characteristics of texture are revealed by MPD and L TX ,1-31.5. The surface texture of the wearing course on asphalt mixtures is the critical factor affecting the friction behaviors of pavement. The present traditional surface structure evaluation index does not provide the range and the distribution of the texture, and most pavement texture polishing equipment does not represent the actual loading action. In this paper, based on a laser profilometer and a spectral analysis, the mean profile depth (MPD) characterizing the pavement macro-texture is calculated, and the spectral parameter (L TX ,1–31.5) characterizing the range and the distribution of the road surface texture is derived. MLS11 equipment is used to polish the wearing course with different design parameters, and the evolution characteristics and influencing factors of the surface texture are studied. The results show that the MPD and the L TX ,1–31.5 could distinguish the influence of the oil–stone ratio and the mixture type on the surface macro-structure of the asphalt mixture, and the results of the variation coefficient of the parallel test are within 3.0%. The decay process of the MPD can be divided into three processes (i.e., the relative decay period, the decay period, and the stable period) and six stages. The decay process of the L TX ,1–31.5 involves the three processes (the relative stable period, the decay period, and the stable period) and four stages. When the oil–stone ratio increases from 4.4% to 5.4%, the attenuation rates of the MPD and the L TX ,1-31.5 decrease. The surface texture of both the GAC-16 and SAS-16 samples are better compared with the AC-16 sample, and the attenuation law of the MPD and the L TX ,1-31.5 value is similar. The loss rates of the MPD of the four aggregates are ranked as follows: limestone > diabase > andesite > granite. The loss rates of the L TX ,1-31.5 of the four aggregates are ranked as follows: limestone > diabase > granite > andesite. [ABSTRACT FROM AUTHOR]