废轮胎热解油(TPO)冷再生沥青混合料路用性能及机理研究

Research on Road Performance and Mechanism of Waste Tire Pyrolysis Oil(TPO)Cold Recycled Asphalt Mixtures

废轮胎热解油(Tire Pyrolysis Oil,TPO)是废旧轮胎热解的副产物。TPO的化学成分与常用沥青再生剂芳香烃类油的化学成分相似,使得TPO能够用作废旧沥青混合料(Reclaimed Asphalt Pavement,RAP)的再生剂,并能恢复RAP的技术性能。采用傅里叶变换红外光谱仪对再生沥青胶结料的化学结构进行了研究,揭示了TPO冷再生沥青混合料的再生机理。采用马歇尔设计方法明确了TPO冷再生沥青混合料的材料组成。研究了TPO的掺量、预活化时间和环氧树脂掺量对再生沥青混合料路用性能的影响规律。研究结果表明:TPO可以软化老化沥青、降低其黏度、重新平衡RAP表面的老化沥青的化学成分和恢复老化沥青的技术性能,但仅用TPO再生的再生沥青混合料的力学性能较差,掺入低剂量的环氧树脂在沥青混合料内部起到了结构补强的作用,极大地提高了TPO再生沥青混合料的各项性能。

Waste tire pyrolysis oil(TPO)is a by-product during the pyrolysis of waste tire.The chemical composition of TPO is similar to that of aromatic hydrocarbon oils of commonly asphalt regeneration agents,which make TPO to be a regeneration agent for reclaimed asphalt pavement(RAP)and restore some of the properties of RAP.Fourier transform infrared spectroscopy was used to study the chemical structure of recycled asphalt to investigate the regeneration mechanism of TPO cold recycled asphalt mixture.Marshall’s design method was adopted to determine the cold recycled asphalt mixture material components.The effects of TPO dosage,preactivation time and epoxy resin dosage on pavement performance of the recycled asphalt mixture were studied.The research results show that TPO can soften aged asphalt,reduce its viscosity,rebalance the chemical composition of aged asphalt on the RAP surface and restore the technical properties of aged asphalt.However,regenerated only with TPO,the mechanical perfor mance of the recycled asphalt mixture is not high.The addition of low-dose epoxy resin plays a role of structural reinforcement within the asphalt mixture,which greatly improves the performance of TPO recycled asphalt mixture.