硅粉/SBS复合改性沥青混合料高温性能研究

Research on high-temperature property of silica fume/SBS composite modified asphalt mixture

采用高速剪切工艺制备硅粉/SBS复合改性沥青,通过车辙试验和浸水车辙试验分析了油石比、短期老化、碾压次数、水、温度和荷载对混合料高温性能的影响。结果表明:对于AC16型硅粉/SBS改性沥青混合料,马歇尔试验确定的最佳油石比较车辙试验动稳定度最大时对应的油石比增大约0.3个百分点;老化会使硅粉/SBS改性沥青混合料的动稳定度增大;随着碾压次数的增多,动稳定度先增大后减小,碾压次数15次时动稳定度达到最大;水的存在会使动稳定度大幅下降;随着温度升高,动稳定度减小;随着荷载的增大,动稳定度大幅下降,粗集料含量较多时下降幅度较小。

High speed shearing technique was used to prepare silica fume/SBS composite modified asphalt. Conventional rutting test and immersion rutting test were adopted to observe the influence of oil-stone ratio,aging, compaction times,water, temperature and load on the high temperature performance of the mixture. The resuks show that： For the silica fume/SBS composite modified asphalt mixture of AC16,the optimum oil-stone ratio of the Marshall test was about 0.3% compared with that of the maximum dynamic stability of the rutting test. Aging process can increase the dynamic stability of silica fume/SBS modified asphalt mixture. With the increase of the compaction times,the dynamic stability increases first and then decreases, and the roller compaction reaches the maximum at 15 times. The existence of water will greatly reduce the dynamic stability of the rutted specimens. The temperature increases and the dynamic stability decreases. With the increase of the ground pressure of the rubber wheel,the dynamic stability decreases sharply,and appropriate coarse aggregate content will slow this trend.