Manufacture And Mixture Performance Research Based On Reactive Ambient Temperature Flame Retardant Asphalt

Hot mix flame retardant asphalt generally has the problems of high energy consumption and heavy pollution.The technology of reactive ambient temperature flame retardant asphalt can be expected to completely solve the problems of high energy consumption and high pollution in tunnel flame retardant asphalt technology.In this paper,decabromodiphenylethane was selected as the main flame retardant to be combined with reactive ambient temperature asphalt.By analyzing the basic performance index and oxygen index test results of asphalt,the amount of flame retardant was preliminarily determined.The orthogonal test was used to determine the optimum content of flame retardant asphalt.On this basis,the high-temperature and low-temperature properties of the reactive ambient temperature flame retardant asphalt and the flame retardant mechanism of the flame retardant were analyzed.Finally,the basic road performance and flame retardant performance of reactive ambient temperature flame retardant asphalt mixture were systematically studied and evaluated.The main contents are as follows:(1)The amount of 10%flame retardant makes the oxygen index of the reactive ambient temperature flame retardant asphalt reach 25.8%,and the oxygen index value increased by 2.8%.The test results of the basic performance of asphalt showed that the flame retardant could improve the high-temperature stability of the reactive ambient temperature asphalt,which had an adverse effect on the low-temperature performance.The orthogonal test determined the best ratio of reactive ambient temperature flame retardant asphalt:reactive ambient temperature asphalt:flame retardant:unsaturated fatty acid solution:silane coupling agent=100:10:10:2.(2)The high temperature rheological performance test and low temperature rheological performance test determined the PG classification of reactive ambient temperature flame retardant asphalt PG88-22.The reactive ambient temperature asphalt modified with flame retardant improved the high temperature performance obviously,and the low temperature performance decreased slightly.(3)TG-DSC curve and DSC curve of reactive ambient temperature asphalt and its flame retardant asphalt were obtained by TG-DSC joint test.From the analysis of the flame retardant mechanism,the HBr produced by the decomposition of the flame retardant decabromodiphenylethane captures the free radicals generated by the pyrolysis reaction of asphalt and delayed the decomposition of asphalt.The termination decomposition temperature of flame retardant asphalt was increased from 641.5 ℃ to above 800℃ and the peak heat flow rate was reduced from-22.7mW/mg to-16.7mW/mg.(4)The Marshall stability of the reactive ambient temperature flame retardant asphalt mixture was greater than 10kN;the dynamic stability of the high temperature rutting test was more than 5000 times/mm;The bending strain at low temperature was greater than 2500με,but the bending strain value decreased as the amount of flame retardant increased;the flame retardant had an adverse effect on the water stability of the mixture.As the amount of flame retardant increased,the residual stability and After the freeze-thaw cycle,the splitting strength ratio decreased.(5)The combustion test of Marshall test piece and rut plate test piece was used to simulate the burning of asphalt pavement.The test results showed that the flame retardant significantly shortened the burning time of Marshall test piece and rut plate test piece,reduced the quality loss,and effectively improved the combustion residual dynamic stability and residual strength ratio.