Analysis Of Performance Of Flame-retardant SBS Modified Asphalt Mixture And Construction In Long Tunnel

According to the characteristics of the Jingxi-Napo Highway in Guangxi province,which has larger proportion and longer length of tunnel,this paper introduced one kind of flame retarding technology into the asphalt concrete pavement of the tunnel to decline the risk of the fire,reduce the soot,and improve the conditions of the tunnel construction to ensure constructors' health and operational traffic safety in the greatest extent.Three kinds of flame retardants were chosen by the investigation and reseach,and then flame retardant SBS modified asphalt was produced.After that some tests had been done,including penetration,softening point and ductility index test,flashing point and firing point,oxygen index and thermal analysis test.The three kind of asphalt were compared and analyzed by the influence of the flame retardant on the high and low temperature performance,flame retarding performance of SBS modified asphalt.Results indicate that flame retardant A can obviously increase the flashing and firing point of SBS modified asphalt and oxygen index compared with the other two kinds of flame retardant.So,it is suggested that flame retardants A is better for this project,and the flame retardant asphalt using flame retardants A has a good stability during construction period.The flame retardant SBS modified asphalt mixture was prepared by using flame retardant and reasonable dosage has been ensured,and then the performance test of mixture were proceeded to verify that these performance all meet the requirements of relevant technical specifications.Finally,by bulk cargo,combustion test of Marshall specimen and cone calorimeter,experimental study of flame retardant performance of flame retardant SBS modified asphalt mixture was carried out.The results show that various indicators of combustion performance of the flame retardant SBS modified asphalt mixture are better than SBS modified asphalt mixture.the flame retardant SBS modified asphalt mixture shows the good flame retardant performance,and has an effectively guarantee on the flame retardant effect of the flame retarding asphalt pavement in the tunnel.The test results in site show that the construction quality of flame retardant SBS modified asphalt pavement in tunnel is good.