温拌橡胶沥青改性工艺及其混合料性能分析

MODIFIED TECHNOLOGY OF WARM RUBBER ASPHALT AND PERFORMANCE ANALYSIS OF THE MIXTURE

为研究温拌橡胶沥青改性工艺,评价温拌剂LQ-1106对混合料降温效果及其对混合料路用性能的影响,采用不同的胶粉掺量、搅拌温度、搅拌时间及温拌剂掺量,基于正交试验方案制备温拌橡胶沥青,分析各因素对胶结料影响权重,确定最佳改性工艺。在此基础上利用可变因素击实方式确定温拌橡胶沥青混合料合适成型方法,并在最佳成型条件下选用SMA级配对比研究温拌橡胶沥青混合料高温稳定性、低温抗裂性以及水稳定性能。试验结果表明,胶粉掺量是影响温拌橡胶沥青性质最主要因素,最优改性工艺组合为胶粉掺量为20%、搅拌温度为200℃、搅拌时间为60min、温拌剂掺量为0.6%;掺入温拌剂后的混合料,成型温度可降低约30℃,且混合料高温稳定性、低温抗裂性较热拌橡胶沥青混合料有一定提高,但水稳定性能略有下降。

In order to study the condition of modification technology of warm rubber asphalt mixture,the temperature-lowered effect of LQ-1106 and its influence on the road performances of asphalt mixture are evaluated.Different rubber contents,stirring temperatures and times,and LQ-1106 contents were prepared,and the weight of each factor of influence of mixture were analyzed,the mixture was made based on the orthogonal test,the optimum condition of modification was obtained.Then the proper molding method was obtained,and the tests about high temperature stability,low-temperature crack resistance and water stability of the mixture were done through the composite gradation of SMA under the method.The results showed that rubber content is the main factor influences the performance of warm rubber asphalt,and the best modified technology contain rubber content 20%,preparation temperature 200℃,stirring 60min,LQ-1106 content 0.6%.It also reveals that the compaction temperature can decrease 30℃by using LQ-1106 and the high temperature stability,and low-temperature crack resistance of the mixture are improved compared with hot rubber asphalt mixture with the water stability decreasing slightly.