Study On The Properties Of A New Type Of Warm Mix Fire Restardant Binder And Stone Matrix Asphalt(SMA) Mixture

Due to the fast development of Chinese transportation industry,highway tunnel projects are increasingly performed.Asphalt pavement has the advantages of low noise,high comfort,easy maintenance and so on.It is widely used in the tunnel pavement engineering.However,there are some disadvantages in the application of asphalt pavement in the tunnel,such as strong hot smoke during the construction period and fire hazards during the operation period.In order to solve these problems,and considering the requirements of environmental protection and energy saving,this paper studies and develops a kind of SMA-13 asphalt mixture with high performance and good cooling effect.Firstly,three kinds of warm mix asphalt and warm mix flame retardant asphalt used in the warm mix SMA-13 asphalt mixture were tested for three major indexes,135 ℃ Brinell viscosity and ultimate oxygen index;then Marshall method andsuperpave gyratory compactor method were used to determine the optimal mixing temperature of three warm mix agents,two fibers and their three admixtures of flame retardant SMA-13 asphalt mixture;and then High temperature rutting test,Water stability test,Low temperature bending test and Semicircle bending fatigue test were carried out for each type of asphalt mixture.Finally,the best temperature mixing agent,the best fiber and the best content were determined by the grey theory analysis method and the economic and environmental benefit analysis.the results of the study are as following:(1)Warm mix agent 1102 and M1 have little effect on the high temperature performance and low temperature performance and viscosity of asphalt,and can improve the aging resistance and flame retardancy of raw asphalt.The warm mix agent Sasobit can enhance the high temperature performance of asphalt,reduce the low temperature performance,viscosity and flame retardancy of asphalt,but has little effect on the aging resistance of asphalt;(2)The Marshall method is not suitable for warm mix and fire retardant SMA-13.The asphalt mixture is designed,and thesuperpave gyratory compactor method is used to achieve the effect.Among the three temperature mixers,M1 has the best cooling effect,and the lower the fiber content is,the better the cooling effect is;(3)Sasobit can greatly improve the high temperature performance and fatigue resistance of asphalt mixture,which has little effect on the water damage resistance,but weakens the low temperature performance of the mixture;M1 and 1102 can improve the water damage resistance of asphalt mixture,but they can improve the high temperature performance The fatigue resistance and low temperature performance have little influence;(4)The road performance of wood fiber asphalt mixture is better than that of polyester fiber asphalt mixture.When the fiber content is reduced,the performance of asphalt mixture will also be reduced;(5)When warm mix agent is M1,the fiber is wood fiber,and the fiber content is0.15%,the cooling range can reach 31℃,the road performance meets the requirements of the specification,and has the advantages of cost saving,good construction performance,green environmental protection,etc.