高温高湿盐环境下SBS改性沥青胶浆的高温性能

基于自行设计的室内盐蚀干湿循环试验，采用动态剪切流变仪，对SBS改性沥青胶浆进行温度扫描试验和多重应力重复蠕变恢复(MSCR)试验. 以3.2 kPa应力下的不可恢复蠕变柔量J_nr,3.2为胶浆高温流变性能评价指标，分析试验环境和干湿循环耦合作用对胶浆流变性能的影响. 采用灰色关联理论，探究J_nr,3.2与常规流变参数、干湿循环次数及试验环境之间的关联性. 结果表明，随着盐蚀干湿循环次数的增加，胶浆的复数切变模量、车辙因子及J_nr,3.2均呈增大趋势，相位角和蠕变恢复率呈减小趋势. 在同种试验条件下，硫酸盐环境对胶浆高温性能的影响最大. J_nr,3.2与改进型车辙因子、试验环境的灰色关联度最大，关联度系数均大于0.93. 建议采用日常清扫、定期洒水冲洗的方式来减小路面盐分的积累，提高高温高湿环境中沥青路面的抵抗变形的能力.

High temperature properties of SBS modified asphalt mastics in high temperature and high humidity salt environment

The temperature scanning test and multiple stress repeated creep recovery (MSCR) test of SBS modified asphalt mastics were conducted by using dynamic shear rheometer based on the self-designed indoor salt erosion and dry-wet cycle test. The unrecoverable creep compliance (J_nr,3.2) at the stress level of 3.2 kPa was used as the evaluation index of high-temperature rheological properties of the mastics. The coupling effects of environment and dry-wet cycles on the rheological properties of the mastics were analyzed. The grey correlation theory was used to explore the correlation between J_nr,3.2 and conventional rheological parameter, dry-wet cycles and test environment. The complex shear modulus, rutting factor and J_nr,3.2 showed an increasing trend with the increase of dry-wet cycles, while the phase angle and creep recovery rate showed a decreasing trend. The sulfate environment has the greatest influence on the high temperature performance of asphalt mastics under the same test conditions. J_nr,3.2 has the largest grey correlation with improved rutting factor and test environment, and the correlation coefficient is greater than 0.93. It is suggested that the method of daily cleaning and regular watering should be adopted to reduce the accumulation of salt and improve the resistance to deformation of asphalt pavement in high temperature and humidity environment.