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In order to enhance the texture and particle retention capabilities of the anti-abrasive seal layer, this paper focuses on the interlocking pattern between the seal and the particles of the pavement, and for the first time considers the base pavement texture, the particle size of the seal, and the amount of seal particles as design variables. The study investigates the relationship between these factor variables and response variables such as texture loss and mass loss. An optimization of the plan design was conducted using the I-optimization method in the mixture design of Design Expert software. The study involved a long-term wear test of 20,000 wear cycles on anti-abrasive seals. The response surfaces corresponding to each response variable were calculated using RSM (response surface method), thereby providing design solutions with high wear-resistant performance. Finally, the rationality and scientific nature of the optimized solutions were verified using three-dimensional texture indices, preliminarily elucidating the texture characteristics of the high wear-resistant performance. The results indicate that combinations of 0.7 kg/m² aggregate usage, 0.8 mm-1.0 mm texture depth, 0.6 mm-1.18 mm aggregate particle size, and 0.75 kg/m² aggregate usage, 1.2 mm-1.3 mm texture depth, 0.3 mm-0.6 mm aggregate particle size experienced the least quality and TD loss. The general texture characteristics of high wear-resistant seal layers include a small Sq value (Sq less than 1.8), a moderate Ssk value (Ssk approximately 0), and a slightly higher Sku value (Sku greater than 3). However, if Ssk is not close to zero (and the absolute value of Ssk is too large), even higher Sku values can result in increased large losses. • The durability of the seal layer is enhanced by improving the interlock between particles and aggregates. • RSM is used to optimize the design of sealing parameters such as aggregate size, aggregate amount, and base texture. • The height distribution of particles is assessed through the kurtosis and skewness measurements in three-dimensional texture analysis. • Recommendations are made regarding the appropriate matching of the base texture with the particle size and quantity. [ABSTRACT FROM AUTHOR]

The current standard in China does not specify the standard test method for determining Poisson's ratio, and the Poisson's ratio used in pavement design is often roughly fixed, which can result in large errors in the calculations and analysis of road structure. In this paper, the research on different test methods for Poisson's ratio is carried out and the non-linear characteristics of tensile and compressive Poisson's ratio on pavement materials under different influencing factors are analyzed. The results indicate that the absolute value of the ratio between transverse rebound strain and longitudinal rebound strain under 50% of the maximum destructive load can objectively characterize the mechanical properties of Poisson's ratio, and it is the optimal measurement method for Poisson's ratio in asphalt pavement materials. The Poisson's ratio of two pavement materials both decreases with the increase of loading rate and gradually tends to a constant value. Cement dosage and temperature are the most significant factors affecting the tensile and compressive Poisson's ratio of cement stabilized crushed stone and asphalt mixture, respectively. Specifically, when cement dosage increases by 1%, the Poisson's ratio of cement stabilized crushed stone decreases by approximately 10%, and the temperature has a significant influence on the difference in tension and compression for Poisson's ratio of asphalt mixture (up to 40%). The asphalt content corresponding to the minimum Poisson's ratio is basically consistent with the optimal asphalt content obtained by the Marshall volume method. Based on these, a quantification value-taking model is established of the tensile and compressive Poisson's ratios of typical asphalt pavement materials varying with multiple factors. The research results can serve as a reference for the scientific value-taking of pavement structural design parameters considering the different mechanical characteristics of materials in tension and compression. • The scientific and reasonable measuring method of Poisson's ratio was established. • The quantitative model of Poisson's ratio affected by many factors was established. • The Poisson's ratio increases with loading speed and gradually tends to stabilize. • The optimum asphalt content mixture by Marshall method has minimum Poisson's ratio [ABSTRACT FROM AUTHOR]

[Display omitted] • The test devices developed in this study were effective in obtaining electrical property parameters. • The resistance, impedance and inductance increase with the decrease of water content, and turn obviously when the water content reaches a certain range. • GY-R and GY-L have the consistency to evaluate the curing characteristics of cold-mixed asphalt. Determination of the rolling time of cold-mixed and cold-laid asphalt mixture is crucial to the operational process and performance of the road. The moisture content of the cold-mixed and cold-laid asphalt mixture is directly related to its curing performance. The research purpose of this paper includes the development of a device for stably testing the electrical properties of cold mixed and cold paving asphalt mixture, the monitoring of water content, and electrical properties of cold mixed and cold paving asphalt mixture at different curing times. The electrical properties of cold-mixed and cold-laid asphalt mixture were tested by a digital bridge instrument (LCR). The relationship model between moisture content and electrical properties was established. The normalization method is used to deal with the electrical performance parameters to avoid the influence of inconsistent initial conditions. The results show that the absolute values of resistance, impedance and inductance of all kinds of emulsified asphalt and their mixtures increase with the decrease of moisture content, and the absolute value of capacitance decreases with the decrease of moisture content. Normalized resistance value, inductance value and impedance value can accurately judge whether the cold-mixed and cold-laid asphalt mixture has been fully cured. The cement absorbs water for hydration, which also increases the mixture's temperature and speeds up the curing rate. When the normalized resistance value is 10 at any A.C. frequency(100 Hz ∼ 100 kHz), it can be considered that the cold-mixed and cold-laid asphalt mixture can be rolled. When the normalized inductance value reaches 100 at a high frequency(100 kHz, 40 kHz), it can also be used as the evaluation index. From the aspects of electrical properties, this paper provided an experimental basis for the construction quality control of cold-mixed and cold-laid asphalt mixture. [ABSTRACT FROM AUTHOR]

• The current US grading system determines limiting temperatures for asphalt binder use. • The low limiting temperature is based on creep modulus and its slope vs loading time. • Current specifications are being challenged and a new criterion has been proposed, called ΔTc. • ΔTc is mostly controlled by the rheological index R that governs its sign. • Care must be taken when trying to predict cracking results from rheological data only. The current Performance Grading system for asphalt binders in the USA, determines limiting temperatures for appropriate binder use. Practically, the low limiting temperature is based on rheological measurements made using the Bending Beam Rheometer (BBR). The absolute value of the creep modulus and/or its slope vs loading time in a log scale, are being used. However, the current specifications are being challenged and it has been proposed adding a new criterion, called ΔTc; its ability to better predict thermal cracking is the subject of intense discussions. In this paper, we mathematically show how ΔTc relates to other binder rheological properties. Then, we discuss the practical consequences in order to highlight the relevant parameters controlling ΔTc. Experimental data are used to substantiate the main findings. This shows that ΔTc is of "pure" rheological origin and care must be taken when trying to predict cracking results from rheological data only. [ABSTRACT FROM AUTHOR]