Heat-reflective coatings, used to reduce the asphalt pavement temperature and urban heat island effect, have a good cooling effect; coating development, however, generally focuses on cooling. This study aims to design a heat-reflective coating with both durability and cooling effect by considering the functions of each component, improving the coating bond strength and abrasion resistance, and conducting laboratory tests and test section verification. The coating developed exhibits bond strength and abrasion resistance 20% and 49%, respectively, higher than those of ordinary coatings. The experiments reveal a cooling effect of red coating up to 10.2 °C, a bond strength of up to 1.20 MPa at 25 °C, and an abrasion rate of up to 25% after 60 min; the cooling effect is basically the same as that for traditional heat-reflective coatings, but the bond strength and abrasion resistance significantly improved. In the analysis of the test section, the cooling effect reaches 7.0 °C, the performance of anti-skid decreases little, and the coating is still usable normally after 4 months.

In this work, the reliability of the vertical vibration testing method (VVTM) is verified using laboratory and field tests. Then, the VVTM, Marshall compaction method (MCM), and modified Marshall compaction method (MMCM) are used to investigate the effects of different compaction methods on the physical and mechanical properties of asphalt mixtures. The results show that the VVTM has the least influence on the aggregate gradation of an asphalt mixture, and the specimens produced using VVTM have the best test accuracy when compared with the field cores. When the density of the asphalt mixture remains fixed, the average mechanical properties, e.g., Marshall stability, compressive strength, splitting strength, and shear strength, of the VVTM specimens are increased by at least 21% compared with those of the MCM specimens. Moreover, the mechanical properties of the mixtures increased by at least 13.2% when the mixture density increases by 1.8%. The results also show that the mechanical strength (Marshall stability, compressive strength, splitting strength, and shear strength) of the asphalt mixture is related to the mixture density and compaction method, whereas the optimal asphalt-aggregate ratio is only related to the mixture density. Moreover, the optimal asphalt-aggregate ratios of the VVTM and MMCM specimens are decreased by approximately 0.3% compared with those of the MCM specimens.

This study investigates the resilient modulus of vertical vibration compacted cement-stabilized macadam (CSM). The reliability of the vertical vibration compaction method (VVCM) for CSM was verified. Then the influences of four factors on the resilient modulus were studied and a resilient modulus prediction equation was proposed. Subsequently, the influences of aggregate type, cement dosage, and gradation on the initial and ultimate resilient moduli were studied. Results show that compared to the quasi-static-compaction method, the VVCM has a smaller influence on the optimum water content and aggregate gradation, and VVCM specimens have a higher correlation with the on-site cores. The increase of cement dosages and curing times can improve the resilient modulus and the proposed prediction equation can accurately predict the resilient modulus growth of the CSM. When the cement dosage and aggregate gradation are identical, the initial and ultimate resilient moduli of the cement-stabilized limestone are the largest, followed by the cement-stabilized granite and sandstone. The initial and ultimate resilient moduli of the CSM increase linearly as the cement dosage increases. Moreover, the skeleton-dense gradation helps to improve the initial and ultimate resilient moduli of the CSM. This study provides guidance for the design and construction of a CSM base.

To reduce asphalt pavement temperature and improve its anti-rutting performance in summer, thermally resistant friction course (referred to as TRFC-13), heat-reflective coating (referred to as HRC) and thermally resistant and heat-reflective coating integrated pavement (referred to as TR-HRC) were developed, and their cooling effect, anti-rutting performance and durability were evaluated. In addition, machine-made sands were applied to improve the anti-skid performance of the coating. The results show that compared with ordinary SMA-13 samples, the surface temperature of the TRFC-13, HRC and TR-HRC samples decreased by approximately 6.8°C, 11.2°C and 13.2°C, respectively. At the air temperature of approximately 40°C, the field road surface temperature of the TRFC-13, HRC and TR-HRC decreased by approximately 7.4°C, 12.2°C and 14.0°C, respectively. The higher the air temperature is, the better the anti-rutting performances of these three kinds of pavement. At the air temperature of 39°C, the dynamic stability of the TRFC-13, HRC and TR-HRC is 1.56 times, 1.86 times and 1.88 times that of the ordinary SMA-13, respectively. The results also show that HRC has a strong abrasion resistance and that spreading 40 wt% of machine-made sands can ensure the coatings achieve the best British Pendulum Number, without influencing its cooling performance.