Study Of Asphalt Flame Retardant And Decreasing Viscosity For Asphalt Pavement Mixture In Tunnel

From the perspective of tunnel safety operation, the long above the tunnel pavement structure is given priority to with cement concrete, but the cement concrete pavement, poor flatness of the sliding resistance, poor, defects such as dust, noise, high reflective. Relatively asphalt mixture pavement structure has good surface keep capacity, driving comfort and good anti-sliding performance of the asphalt concrete pavement structure of tunnel pavement has gradually become the trend.But the tunnel is paved with asphalt mixture pavement, because of the tunnel is in a state has a closed space structure, and asphalt belong to the combustible material, inside the tunnel ventilation is poor, if the fire accidents, asphalt mixture of asphalt possible under the condition of high temperature combustion and release poisonous and harmful gases and soot, bring great difficulty relief.Tunnel flame retardant asphalt pavement mixture viscosity technology research purpose is through the certain technology to the preparation of flame retardant asphalt mixture, in order to reduce the harm of fire accident; At the same time, considering the particularity of tunnel pavement construction to reduce the common hot mix asphalt mixture construction produces a lot of smoke, reduce the influence on the construction technical personnel health and improve work efficiency, using technology to reduce the temperature of the mixture of viscosity reduction and less smoke release quantity.In this paper, through a large number of experiments, studies the asphalt adding different content of flame retardant, the determination of three indicators, the LOI value, and the storage stability of the asphalt, determine the content of the flame retardants, adding flame retardants in the matrix asphalt content was 6%, the largest in the SBS modified asphalt flame retardant maximum dosage is 10%; After the determination of the viscosity agent is added in the asphalt asphalt basic index and apparent viscosity, viscosity-temperature curve drawing, in turn, determine the content of the viscosity agent, SA in the SBS modified asphalt viscosity agent content is 4%, biggest TPSA dosage is 3%; SA in the matrix asphalt viscosity agent content is 3%, TPSA content is 3%.By orthogonal design of experiment of adding flame retardant agent, viscosity agent of asphalt cement experiment analysis, the optimal combination of the dosage of draw ratio, matrix asphalt adding viscosity agent and the optimal formula of flame retardants for: 3%SA + 6% flame retardant, 3% TPSA + 5% flame retardant; SBS modified asphalt viscosity agent is added and the optimal formula of flame retardants for: 3%SA + 7% flame retardant, 3%TPSA+7% flame retardant.In asphalt mixture performance study concluded that under the condition of the optimal combination of asphalt mixture of road performance meet the requirements of the current specification, through direct combustion test show that the asphalt mixture flame retardant effect is obvious, and compared with the ordinary hot mix asphalt mixture construction temperature are reduced.