Study On Pavement Performance Of Mixed Fiber Asphalt Mixture

Asphalt concrete pavement is widely used in road engineering due to its advantages of low traffic noise and high stability.In recent years,with the rapid development of China's transportation,asphalt pavement is under increasing pressure during service,which cause various use problems.It becomes crucial to study high-quality roads.Adding fibers to the asphalt mixture is an important way to improve the performance of asphalt concrete pavement.Different fiber have different emphasis on improving the performance of asphalt pavement.This paper explores into the road performance of fiber asphalt concrete pavement,which was mixed in brucite fiber and sepiolite fiber that is reported good performance in road.It motivates people to have multiple thinking of choosing reasonable fiber blending scheme,and provide a reference for studying high quality asphalt concrete roads.The main research contents are as follows:(1)The performance of fiber and aggregate was tested,and the mixture ratio of AC-13 asphalt mixture was determined by sieving results,the optimum amount of fiber and the asphalt-aggregate ratio for single fiber blending is determined by Marshall test.The total amount of mixed fibers is 0.3%,the blended amounts of brucite fiber and sepiolite fiber were designed,the operation according to the ratio of 1:4,2:3,3:2,4:1,the optimum asphalt-aggregate ratio of different proportions fiber blending were obtained through the experiment.(2)In order to determine the improvement effect of asphalt concrete pavement after adding fiber,rutting test,beam bending test and immersion Marshall test were used to test the performance of asphalt concrete pavement.The test results show that the addition of fiber can improve the high temperature performance,low temperature performance and water stability of asphalt mixture,the performance of the mixed fiber is better.For the high temperature,low temperature,and water stable conditions,the average increase can reach 20.3%?12.4% and 6% respectively.(3)Due to different pavement environment,this research analyzed the performance for non-,single-and mixed-fiber asphalt mixture under high and low temperature,water stability employing efficacy-coefficient methodology given equal and unequal weights respectively;determined the comprehensive efficacy-coefficient of various condition considering the price of materials;and then,proposed the best fiber mixed scheme with the performance-price ratio.From the analysis,the ratio of brucite and sepiolite fiber mixed in 1:4 is the most cost-effective on ordinary environments and rainy regions.On high temperature area and low temperature area,the ratio of two fibers into the asphalt mixture at 2:3 is cost-effective.