高 RAP 掺量热再生 SMA 路面高效再生路用性能研究

摘要

In order to utilize the residual strength of SMA pavement,and improve the overall road performance of pavement structure,Studied the road performance and Paved road test of reclaimed SMA -16 Mixture.Based rutting,cold bending,frozen off,immersion Marshall test,freeze﹣thaw splitting and a four﹣point loading fatigue test to study the influence of RAP content on road performance of reclaimed SMA mixes road performance,and discussed the technology feasibility of Efficient Reclaimed SMA Pave﹣ment with High RAP Content.The test results show that,with RAP content increases,the reclaimed of SMA mixture temperature stability is improved,and low temperature cracking resistance and fatigue resist﹣ance decreases with increasing RAP content,low temperature cracking resistance is constrained to in﹣crease RAP﹣doped the amount of technical bottlenecks.When RAP content less than 30% of the renew﹣able SMA mixture pavement performance specifications meet the technical requirements of the existing construction,after adding 30% recycled materials SMA mixture fatigue performance at reduced levels of each strain to a lesser extent,but RAP content reached 50% after the SMA mixture fatigue life more sig﹣nificant decline.Laboratory test and engineering application results show that the thermal reclaimed SMA asphalt mixture can be used in the surface layer,waste SMA asphalt pavement material recycling technol﹣ogy is feasible and efficient,its economic and social benefits significantly.%为了利用 SMA 路面的残余强度，提高路面结构的综合路用性能，进行了再生 SMA －16混合料路用性能研究和试验路铺筑，基于车辙、低温弯曲、冻断、浸水马歇尔、冻融劈裂和四分点加载疲劳试验研究了4种 RAP掺量的再生 SMA 混合料路用性能，探讨了废旧 SMA 沥青路面材料高效再生技术的可行性。试验结果表明，随着RAP 掺量增大，再生 SMA 混合料高温稳定性提高，而低温抗裂性和抗疲劳耐久性随 RAP 掺量增大而降低，低温抗裂性是制约增大 RAP 掺量的技术瓶颈。RAP 掺量小于30％时，再生 SMA 混合料的各项路用性能均满足现行施工规范技术要求，掺加30％再生料后 SMA 混合料疲劳性能在各应变水平下降低幅度较小，但 RAP 掺量达到50％后SMA 混合料疲劳寿命下降较为显著。室内试验及工程应用结果表明，热再生 SMA 沥青混合料可用于表面层，废旧SMA 沥青路面材料高效再生技术是可行的，其经济效益和社会效益显著。