高 RAP 掺量厂拌温再生 SMA 16混合料耐久性试验研究

摘要

In order to solve the problem of old material high temperature carbonization,feeding channel blockage,RAP content is less than 30% and make full use of the residual strength of SMA road mixture,improve the long-term performance of the pavement structure.This article researched on road performance and test road paving of SMA — 16 warm reclaimed mixture with different RAP content.Based on rutting,low temperature bending,frozen,Marshall immersion,freeze-thaw splitting and quartile load-ing fatigue test to study the dosage of 30%,40%,50% RAP renewable road performance of SMA mix-ture of temperature,discussed the effective temperature mixing waste SMA asphalt pavement materials re-generation technology is feasible.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 re-sistance 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.%为了解决热再生旧料加热温度过高碳化、送料通道堵塞、RAP 掺量不高，并充分利用 SMA 路面的残余强度，提高路面结构的长期使用性能。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30％、40％、50％RAP 掺量的温再生 SMA 混合料路用性能，探讨了废旧 SMA 沥青路面材料高效温拌再生技术的可行性。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，温拌再生 SMA 改性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。