Influence Of Polyester Fiber On Water Stability Performance Of Permeable Asphalt Mixture

With the rapid development of highway construction and continuous improvement of people’s living standards, many new asphalt pavements have appeared. The air voids of permeable asphalt pavement is big, it has good drainage performance, increasing the driving security and comfort. At the same time, the permeable asphalt pavement can also reduce the noise produced by the vehicles and lower the surface temperature of the pavement in hot day, it is an environmental pavement. The polyester fiber can improve the performance of the drainage asphalt mixture, and prolong service life of the asphalt pavement. Therefore, the mechanical performance and water stability performance of permeable asphalt mixture with polyester fiber content of0.3%,0.35%,0.4%,0.45%,0.5%were studied. The applying of ultrasonic methods in permeable asphalt mixture was studied. The main conclusions are as follows:(1)The initial content of asphalt has been acquired by the method of calculation. Based on the Schellenberg binder drainage test, the optimal asphalt content with different fiber content has been studied, the results show that polyester fiber can reduce the binder drainage loss of asphalt mixture. When the fiber content is0.4%, the binder drainage loss of asphalt mixture is the least, and the optimal asphalt content increases with the growth of polyester fiber content.(2)Based on Marshall test, the change laws for Marshall stability and flow value of permeable asphalt mixture have been studied with different polyester fiber content, The results show that when the fiber content is0.4%, Marshall stability and flow value is the largest. The air voids of permeable asphalt mixture decrease with the growth of polyester fiber content, which is different with the dense gradation asphalt mixture.(3)Based on freeze-thaw splitting test, the change laws for splitting strength and water stability performance of permeable asphalt mixture have been studied with different polyester fiber content, when the polyester fiber content is0.4%, the splitting strength and the ratio of freeze-thaw splitting strength are the largest, witch indicates that water stability performance is the best.(4)The specimens have been tested by ultrasonic wave before freeze-thaw splitting test. The results show that the correlation between splitting strength and ultrasonic wave velocity of specimens with freeze-thaw is better than the specimens without freeze-thaw, the ultrasonic test technology can be used to predict the splitting strength of permeable asphalt mixture.