| As the economy of China flourishes,people’s demand for better travel experience is rising gradually.Besides,the traffic pressure on road has aggravated by the"last mile"task of goods circulation in the e-commerce industry,leading to faster deterioration of road performance.In response to the demand of people and the increasing traffic pressure,hot-mix thin-layer overlays are applied to preventive maintenance by more road management departments,such as Nova Pave,which can significantly improve drainage,anti-skid,and noise reduction performance of pavement.However,due to the utilization of super-high-viscosity modified bitumen(CGN),the construction temperature of Nova Pave is fairly high,resulting in environmental problems.For the purpose of implementing the concept of sustainable development,combination between warm mix asphalt technology and Nova Pave technology was investigated in this study,also this study endeavored to put forward an engineering feasible and economically reasonable solution to the above problems.In the beginning,the basic characteristics of CGN were investigated in this study.It was noted that Sasobit,Evotherm M1,warm-mix additive A,and warm-mix additive B could all increased the softening point of CGN.Besides,Sasobit reduced penetration and ductility,while Evotherm M1,warm-mix additive A and warm-mix additive B had an enhanced effect instead.In addition,the rotational viscosity could be reduced to some extent by incorporating warm-mix additives.Sequentially,a series of rheological experiments were conducted to examine the rheological properties of bitumen in this study.It turned out that the anti-aging property of CGN and its high temperature performance grade could be improved by warm-mix additives.Additionally,its fatigue life could be extended by Sasobit and warm-mix additive B,while worse performance were shown due to Evotherm M1 and warm-mix additive A.Employing sigmoidal model,the master curves of complex shear modulus G~*and phase angleδshowed great goodness of fit,which can effectively analyze the dynamic mechanical behavior of bitumen within a wide frequency spectra.As supplement,the mixing temperature of mixture was determined based on the volume characteristics of the mixture,and the samples of mixture were prepared for related test.Following conclusions were made under the premise of lowering the construction temperature.The rutting resistance of CGN mixture could significantly be improved by Sasobit,while the rest warm-mix additives had neglectable effect;the low-temperature crack resistance of the mixture would be weaken by Sasobit,while the rest warm-mix additives improved it;all warm-mix additives had a negative impact on the moisture susceptibility and durability of CGN mixture,but due to the superior performance of CGN,the impact was insignificant;the fatigue life of CGN mixture could be greatly extended by Sasobit,while the rest warm-mix additives had little effect on the fatigue life of CGN mixture.Eventually,based on a case model,a quantitative analysis of energy consumption and production cost of the CGN warm-mix asphalt mixture was carried out.The analysis results showed that employing warm-mix asphalt technology could significantly reduce energy consumption during production and had promising economic benefits. |
