再生沥青混合料级配组成设计以及路用性能研究

Study on Gradation Composition Design and Road Performance of Recycled Asphalt Mixture

废旧沥青混合料(RAP)回收利用是近年来沥青路面可持续发展和经济有效发展的热点问题。通过使用合适的再生剂可以恢复铣刨料中旧沥青的高低温流变性能和力学性能。本文通过用自主开发的再生剂与市售再生剂制备再生沥青混合料并进行车辙试验、低温弯曲试验、浸水马歇尔试验、冻融劈裂试验和四点弯曲疲劳试验对再生沥青混合料的高低温性能、水稳定性、疲劳性能进行评价。试验结果表明所研制的再生剂能较好地恢复铣刨料的路用性能。在铣刨料中掺入自主研发的再生剂会降低混合料的动稳定度,提高沥青混合料的最大弯拉应变、残留稳定度和冻融劈裂强度比,这说明自主研发的再生剂改善了铣刨料中旧沥青的流变性能,同时再生沥青混合料的耐久性也得到了较大改良。与所选的市售再生剂相比,使用自主研制的再生剂能改善再生沥青混合料的路面性能。

Recycling of waste asphalt mixture (RAP) is a hot issue in sustainable and economic development of asphalt pavement in recent years. The high and low temperature rheological properties and mechanical properties of the old asphalt in milling materials can be restored by using appropriate regenerating agents. In this paper, the high and low temperature performance, water stability and fatigue performance of recycled asphalt mixture were evaluated through rutting test, low temperature bending test, soaking Marshall test, freeze-thaw splitting test and four-point bending fatigue test. The test results show that the regenerating agent developed can better restore the road performance of milling material. Incorporating a self-developed regenerant into the milling material will reduce the dynamic stability of the mixture and increase the maximum flexural strain, residual stability and freeze-thaw splitting strength ratio of the asphalt mixture. This shows that the self-developed regenerant has improved the rheological properties of the old asphalt in the milling material, and the durability of the recycled asphalt mixture has also been greatly improved. Compared with the selected commercial recyclers, the self-developed recyclers can improve the pavement performance of recycled asphalt mixture.