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To simulate the influence of the corrosion environment caused by snow-melting agent on pavement, an asphalt mixture was treated by dry-wet cycle in a NaCl solution with various concentrations. The rutting test, bending test, freeze-thaw splitting test, immersion Hamburg wheel-track test, industrial computed tomography (ICT) test, and scanning electron microscope (SEM) test were conducted to evaluate the adverse effect of snow-melting agent on road performance, durability, and the microstructural characteristics of SMA13, AC13, and SUP13 asphalt mixtures. The damage mechanism of performance for asphalt mixtures in a corrosion environment was also discussed. The results show that the road performance and durability of SMA13, SUP13, and AC13 asphalt mixtures decrease by various extents after being treated by the method of dry-wet cycle in chloride salt solution. Among the three kinds of asphalt mixture, SMA13 shows the best resistance to the corrosion of NaCl solution, followed by SUP13 and AC13. After being treated in salt solution, the void parameters such as total void volume, average void volume, equivalent void diameter, and air void of a Marshall specimen grow fast first and then tend to stabilize. The crystallization expansion of NaCl crystals results in structural damage inside the mixture, and then the strength of the asphalt mixture greatly declines, leading to the deterioration of road performance and durability in a salt corrosion environment. SMA13 asphalt mixture is recommended for pavement surface layers where the snow-melting agent is often used. [ABSTRACT FROM AUTHOR]

• The HVM asphalt mixture composed by SBS compound modified asphalt has advantages in construction workability and comprehensive properties. • Construction workability of HVM asphalt mixture is significantly affected by the asphalt type and mixing temperature, and the latter influences more significantly. • The high viscosity modifier can be replaced with the self-developed HVM asphalt with SBS compound modifier to prepare SMA mixture of steel deck pavement. To seek the optimum asphalt binder used in stone mastic asphalt (SMA) mixture of steel deck pavement, the common modified asphalt in the SMA-13 mixture was replaced with high viscosity modified (HVM) asphalt, and the four kinds of HVM asphalts were selected in this paper. The different test methods such as experimental device of mixing power at different velocities, rutting test, Hamburg wheel tracking device(HWTD) test, bending test at low temperature and indirect tensile fatigue test were conducted to evaluate the construction workability, temperature stability, water stability and fatigue performance of HVM asphalt mixture. Besides the performance difference of various HVM asphalt mixture was also discussed. The results show that construction workability of SMA-13 mixture is significantly affected by the asphalt type and mixing temperature, and the influence of mixing temperature on construction workability is more obvious. Besides it is proved that the construction workability of asphalt mixture is influenced by asphalt viscosity and mineral aggregate. The SMA mixture with self-developed HVM asphalt composed by the linear and star styrene-butadienestyrene block copolymer (SBS) modifier has advantages in construction workability and comprehensive properties. Thus the above asphalt can be selected to prepare SMA mixture applied in steel deck pavement. The construction workability, high temperature performance and fatigue performance of HVM asphalt mixture with SBS compound modified asphalt are close to HVM asphalt mixture with TPS additive or HVM asphalt mixture with SINOTPS, and the the former low temperature performance and water stability are superior to HVM asphalt mixture with TPS additive and HVM asphalt mixture with SINOTPS. The dosage of SBS compound modifier in HVM asphalt is just 6.0%, and the blending ratio of linear SBS modifier and star SBS modifier in the compound modifier is 2:1. It means that the self-developed HVM asphalt with SBS compound modifier has the high performance-price ratio. The reduction of key modified materials in HVM asphalt will be conducive to saving the construction cost of pavement, which will promote the HVM asphalt with SBS compound modifier applying in SMA mixture of steel deck pavement. [ABSTRACT FROM AUTHOR]

• The permanent deformation of asphalt mixture under coupling effect was discussed. • Effect of moisture, overload and low loading frequency needs to be considered. • Anti-rutting agent PR with dosage of 0.45% was recommended for asphalt mixture. To evaluate the influence of vehicle load and driving speed on permanent deformation characteristic of asphalt mixture in high temperature and rainy areas, the Hamburg wheel tracking test was conducted under different test conditions by changing the wheel load, loading frequency and test environment. The permanent deformation characteristic of asphalt mixture under coupling effect of moisture, overload and loading frequency was discussed. Meanwhile, three kinds of anti-rutting agents commonly used in engineering were selected, and the influence of various anti-rutting agents on permanent deformation characteristic of asphalt mixture was also studied by rutting test and Hamburg wheel tracking test. The results show that the moisture, load and loading frequency are important factors affecting the permanent deformation characteristic of asphalt mixture. Under coupling effect of moisture, overload and low loading frequency, the ability of asphalt mixture to resist the generation and development of permanent deformation is poor. The influence of coupling effect of moisture, overload and low loading frequency needs to be considered when evaluating the anti-rutting performance of asphalt mixture. After the addition of anti-rutting agent, the dynamic stability of asphalt mixture increases significantly first, and then tends to be gentle when the dosage of anti-rutting agent exceeds 0.45%. The difference of improvement effect of various anti-rutting agents on rutting resistance of asphalt mixture is obvious, and the improvement effect is in order of PR. PLASTS (PR) > RESIN ALLOY (RA) > Duroflex (Df). The anti-rutting agent PR with dosage of 0.45% is recommended to improve the resistance of asphalt mixture to permanent deformation. The research results can provide some references for improving the rutting resistance of asphalt pavement in high temperature and rainy areas. [ABSTRACT FROM AUTHOR]