Research On Application Of Warm-mixed Flame Retardant Asphalt Mixture In Tunnel Pavement

Due to the small space inside of the tunnel,hot mixture asphalt construction at a higher temperature,release large amounts of gases,smoke,not only affect the surrounding environment and workers’ health,but also have severe effects on construction machinery performance and quality;flammability of asphalt pavement of the tunnel results a big fire hazard.In view of the above two questions,this article on warm mixed asphalt modification and flame retardant modification,with a view to obtaining a better road performance and reducing pollution,protecting human health and safety flame retardant high performance of warm retardant asphalt.Firstly,orthogonal range analysis method was used to get all the factors influence on warm flame retardant asphalt mixture of viscosity and limiting oxygen index level,a warm flame retardant asphalt preparation programme was selected.Influence on performance of asphalt was studied using three main indexes test,it showed that warm agent and flame retardant agent can improve the high temperature performance of SBS modified asphalt,and is unfavorable to its low temperature resistance.On warm flame retardant asphalt for dynamic shear rheological test,results showed that warm mixed modified agent can improve asphalt of high temperature performance;complex modulus of asphalt and rut factor G* ? sinδ with temperature in half logarithmic coordinates have good linear relationship;after RTFOT complex modulus G* and rut factor G* ? Sinδ were 1-2 times higher than the original,and reducing with increase of temperature.Then,the proportion design of warm mixed flame retardant asphalt mixture was carried out;the porosity rate of warm mixed flame retardant asphalt mixture was determined under different temperature condition,it showed that with temperature increased,asphalt mixture pore rate constantly reduced;when keeping hot asphalt mixture in 165℃ hit real temperature of target pore rate,warm flame retardant asphalt mixture of hit real temperature can be reduced 25℃.High temperature stability,low temperature crack resistance,water resistance and fatigue resistance of warm flame retardant asphalt mixture were studied,it showed that warm agent and efficient flame retardant agent helped increasing the mixture rutting resistance and resistance to water damage,fatigue resistance and low temperature anti-cracking performance was harmful.Burning time,mass loss,stability were studied on the flame retardant performance of warm flame retardant asphalt mixture,and it showed that flame agent can not only improve the flame retardant properties of asphalt mixture,but also guarante the pavement performance after burning.Finally,construction technology and quality control techniques of warm flame retardant asphalt mixture were described,the quality of the project was tested,the results showed that the construction quality was good.