天然湖沥青+SBS复合改性沥青混合料性能研究

Research on Performance of Trinidad Lake Asphalt Added with SBS-modified Asphalt Mixture

将天然湖沥青与SBS改性沥青进行复合,以期进一步提高改性沥青的综合路用性能。分别采用基质沥青(B)、SBS改性沥青(S)、湖沥青+基质沥青(BT)、湖沥青+SBS复合改性沥青(ST)配制AC-20、SMA-13两种类型的沥青混合料,通过试验分析复合改性沥青对混合料的高温性能、低温性能、水稳定性和疲劳性能的影响程度。试验结果表明:对于AC-20,ST混合料的动稳定度、最大弯拉应变相对BT混合料提高了56.8%,85.6%,相对B混合料提高了147.4%,71.9%,相对S混合料提高了13.6%,43.5%;对于SMA-13,ST混合料的动稳定度、最大弯拉应变相对BT混合料提高了43.0%,73.0%,相对S混合料提高了41.3%,53.8%。ST混合料的疲劳性能明显优于BT混合料。ST改性效果较BT、S显著提高。以水稳定性来看,复合改性沥青对混合料类型的依赖性不显著,而对SMA-13其他性能的提高幅度均大于对AC-20的作用。

In order to improve the comprehensive road performance of modified asphalt further, Trinidad lake asphalt is compounded with SBS -modified asphalt. Base asphalt （B）, SBS modified asphalt （S）, Trinidad lake asphalt added with base asphalt （BT） and Trinidad lake asphalt added with SBS modified asphalt （ST） are applied to compound AC -20 and SMA - 13 asphalt mixtures respectively. The influence of composite modified asphalt on the mixture about high temperature stability, low temperature stability, water stability and fatigue performance are analysed through experiment. The test result shows that （1） for AC -20, the dynamic stability and the maximum tensile strain of ST mixture is improved by 56. 8% and 85.6% respectively compared with BT mixture, improved by 147.4% and 71.9% respectively compared with B mixture, and improved by 13.6% and 43.5 % respectively compared with S mixture; （2） for SMA -13, the dynamic stability and the maximum tensile stress of ST mixture is improved by 43.0% and 73.0% respectively compared with BT mixture, improved by 41.3% and 53.8% respectively compared with S mixture; （3） the fatigue performance of ST mixture is obviously better than that of BT mixture, the modification effect of ST is clearly improved compared with BT and S; （4） the composite modified asphalt is not significantly dependent on the mixture type for the water stability, but for the other properties of SMA - 13 the increases are greater than those of AC -20.