Viscoelasticity property of bitumen is closely related to the service life of bituminous pavement. This paper evaluated the impact of one of the most efficient and widely used nanomaterials in various industries called hydrophobic nanosilica on the viscoelasticity property of bitumen and asphalt mixture. In this paper, three hydrophobic nanosilica modified bitumens and asphalt mixtures were researched by conventional physical properties test, SEM test, FTIR test, DSC test, DSR test, static creep test and dynamic creep test. The results showed that the introduction of hydrophobic nanosilica could strengthen the viscosity of asphalt more effectively and had better dispersion than hydrophilic nanosilica in asphalt. From conventional physical properties test and rheological performance test, hydrophobic nanosilica could weaken the temperature susceptibility of bitumen observably. From DSR test, hydrophobic nanosilica modified asphalt had a lower sensitivity and dependence on temperature and frequency than hydrophilic nanosilica modified asphalt. The Cole–Cole diagrams indicated that hydrophobic nanosilica exhibited good compatibility with asphalt compared with hydrophilic nanosilica. Newly formed chemical bonds were found in the hydrophobic nanosilica modified asphalt and its mixture with stone according to SEM test, FTIR test, and DSC test, which is the biggest difference from the modification mechanism of hydrophilic nanosilica modified asphalt. Through static and dynamic creep test, it found that the addition of hydrophobic nanosilica can significantly reduce the creep strain at the same temperature.

The increase in cost of bitumen and polymer modifiers and the importance of silicon waste material management have encouraged pavement researchers to use reusable sustainable sources. Oil shale waste powder (OSP) is considered a silicon waste material, and when used in pavement prevents leaching. However, OSP, as an acidic inorganic material, has compatibility issues with asphalt, and its use with ashpalt should be considered carefully. This paper investigates the pavement performance and modification mechanism of OSP and silane coupling agent (SCA) composite modified asphalt and asphalt mixture according to conventional physical property tests: thermogravimetric analysis (TGA), fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and a pavement performance test. The test results showed that the incorporation of OSP and SCA improved the overall properties of asphalt and asphalt mixture and the direct mixing method is more effective than the surface pretreatment method for the modification of composite modification of asphalt. Moreover, the FTIR test and DSC test indicated that the incorporation of OSP and SCA creates new chemical bonds and changes the form and quantity of the crystalline component and the transformation of components in the bitumen.

In the asphalt–aggregate system, the aggregate-bitumen interface cohesive and adhesive bond determine the mechanical properties of asphalt pavement. The presence of moisture leading to adhesive failure at the binder-aggregate interface and/or cohesive failure within the binder or binder-filler mastic is the main mechanisms of moisture damage in the spring-thaw season. In order to evaluate the effect of nano hydrophobic silane silica (NHSS) on aggregate-bitumen interface bond strength in the spring-thaw season, an aggregate-bitumen interface bond strength test was proposed to quantify the interface bond strength of base asphalt and NHSS modified asphalt. Then, the effect of temperature, freeze-thawing cycles and moisture on aggregate-bitumen interface shear strength of base asphalt and NHSS modified asphalt was also discussed. The results illustrated that the shear failure dominated the aggregate-bitumen interface bonding failure in the spring-thaw season, and temperature and moisture had a significant effect on interface shear strength of modified and unmodified asphalt. Moreover, the addition of NHSS could increase the aggregate-bitumen interface shear strength under any working conditions. Furthermore, the moisture damage model of aggregate-bitumen interface shear strength of base asphalt (BA) and NHSS modified asphalt was established based on a research method combining numerical calculations and laboratory tests.

As a key component of a swivel bridge, the spherical hinge is a steel-concrete structure, which is susceptible to moisture damage during waiting time. In this paper, spherical hinge moisture damage prevention is investigated comprehensively from two aspects of impermeable concrete and steel-concrete interface waterproof coating. Three impermeable concretes were prepared and tested by the compressive strength test, splitting tensile test, four-point bending test and the impermeability test. The test results illustrated that addition of cementitious capillary crystalline active masterbatch (CCCAM) and polypropylene fiber (PP) could improve the toughness and brittleness of concrete. The addition of CCCAM was an effective technique for improving the permeability of concrete. However, the incorporation of PP and CCCAM at the same time cannot improve the impermeability of concrete. This may be because the chaotic support structure formed by PP prevents the infiltration and uniform dispersion of CCCAM. A waterproof coating consolidation performance test was proposed to quantify the interface bond strength of waterproof coatings and assess the impact of temperature, moisture and freeze-thawing cycles on consolidation performance of waterproof coatings. The test results showed that temperature had a significant effect on the interface consolidation property of waterproof coatings and the optimal dosage of SBS modified asphalt (SBS), polyurethane (PLT) and unsaturated polyester resin (UPLS) waterproof coating is 1.18kg/m², 0.95kg/m² and 1.15kg/m², respectively. Moreover, it was found that PLS waterproof coating maintained excellent properties in complex environment. This is because PLS has excellent shear strength and rubber characteristics, and it can form a hard–soft–hard transition layer between the concrete and steel, reducing the impact of environmental factors.

Open graded friction course (OGFC) is a high permeable mixture used to reduce noise, improve friction. However, limitations with the use of OGFC are due to the relatively low strength and stiffness. Therefore, investigating environmental and economic benefits, as well as service life of OGFC technology is the future of the pavement. In this study, a new modified OGFC (SM-OGFC) was prepared by replacing the fine aggregate below 4.75 mm in OGFC with the oil shale waste (OSW), and the silane coupling agent modifier was used to assist modification. The preparation process of SM-OGFC was optimized by central composite design, to obtain an SM-OGFC with the best mechanical properties. The Marshall test, rutting test, −15 °C splitting test, −10 °C beam bending test, immersion Marshall test, spring-thawing stability test, Cantabro test and permeability test were conducted to evaluate the properties of SM-OGFC. The results prove that SM-OGFC has excellent overall performance in comparison with OGFC and styrene-butadiene-styrene (SBS) modified OGFC. Furthermore, Scanning Electron Microscopy (SEM) observation illustrates that the unique laminar columnar connected structure and cell-like structure antennae of OSW could be the main reasons why SM-OGFC obtained excellent performance. Furthermore, economic analysis indicated that the SM-OGFC mixture had higher cost effectiveness.

This study mainly uses PFC (particle follow code) to simulate the void characteristics of permeable asphalt mixture, and uses these to simulate the silting process. Then, a tire drop test was used to evaluate the noise reduction performance of permeable asphalt concrete. Finally, a self-made ring rutting test machine was used to simulate the silting process. Through experiments, the following conclusions were obtained: 1. The critical size of the sludge particle size is 0.3 mm–0.6 mm. 2. The quality of the water-permeable asphalt concrete specimens increased by 13% before and after silting, and the porosity of the specimens finally decreased from about 20% to about 8%. The water-permeable function only retained less than 20% of the original, and the water-permeable function was basically lost. 3. By measuring the road noise detection, it was found that the road noise is directly proportional to the degree of blockage of the permeable road. Compared with the original road with a perfect permeable function, the road noise of the completely blocked road increased by about 4 decibels. This study reveals the silting process of permeable asphalt mixture and the key particle size of the silt, which is of great significance for the detection, cleaning and maintenance of permeable asphalt pavements.