热阻沥青混合料的降温效果及路用性能评价

Evaluation on Temperature Reduction and Road Performances of Thermal Resistance Asphalt Mixture

为了研究热阻SMA混合料的降温效果和路用性能,以高铝质耐火集料替代天然集料设计热阻SMA;制作尺寸为30cm×30cm×10cm的SMA试件,测试试件表面和中间深度处的温度;对SMA混合料进行了车辙、低温弯曲、残留稳定度和冻融劈裂强度比试验。研究结果表明,材料的导热系数越低,热量就越难在路面内部传递,进而会降低路面温度的白天温度和提高夜间温度;比起普通的SMA,粗集料热阻SMA和全集料热阻SMA的路表温度分别降低6.3℃和8.0℃,路面内部温度分别降低5.2℃和7.2℃;热阻SMA的高温性能较普通SMA有大幅提高,而低温性能和水稳定性则降低,但路用性能满足《公路沥青路面施工技术规范》的要求。

To investigate the cooling effect and road performances of the thermal resistance SMA, high aluminum refractory aggregate was utilized to design the thermal resistance SMA instead of natural aggregate. SMA specimens with the size of 30 cm× 30 cm× 10 cm were made to test the temperature of surface and middle depth. Rutting,low-temperature bend,residual stability and freeze-thaw splitting strength tests were conducted on SMA mixtures. The results show that the lower the coefficient of thermal conductivity of the material, the more difficult the heat transfer will be within the pavement,which results reducing pavement temperature the daytime and raising pavement temperature at night. Compared with ordinary SMA, surface temperature of coarse aggregate thermal resistance SMA and complete aggregate ther real resistance SMA decrease 6. 3℃ and 8.0℃ respectively,and internal temperature reduce 5.2 ℃ and 7.2℃ respectively. The high-temperature properties of thermal resistance SMA greatly increase than ordinary SMA, while the love temperature performance and water stability decrease, and the above road performances can meet the requirements of ＂Technical Specification for Construction of Highway Asphalt Pavements＂.