Fractal Study On The Modification Mechanism Of Fiber-enhanced Asphalt Concrete

Modern traffic develop in the direction towards the high-speed, heavy haul, high flow and channelization obviously,asphalt pavement has many problems that proposed a severe challenge to road builders, such as serious early damage, life inadequate, lower surface properties, rutting and cracking serious and so on. Polyester fiber asphalt concrete has good road performance, therefore, polyester fiber asphalt concrete have more and more application. But the modification mechanism of polyester fiber asphalt concrete need deeply study.Fractal geometry is a non-geometry rules for the study of geometry. Fractal research "is self-similar, self-affine the fine structure" of the evolution of complex systems theory of the important methods, fractal theory organically combined with materials science and engineering technology, and integrated the new material guidance in the development and application have important theoretical value and economic significance. Study show that crack generation and extension have significant fractal characteristic under low temperature load. Therefore, study on it by means of fractal theory and fractal dimension have a certain theory value.In the paper, starting with the mechanism of asphalt concrete crack generation and extension, using digital cameras, through indirect tensile fracture test (split test) detailed observations of asphalt concrete fracture in the entire process of internal crack initiation, expansion, clustering and eventually undermine the evolution of mechanisms. Access to the entire process of asphalt concrete fracture in different loading conditions during the crack propagation and micro-structural changes in the photo, and used a computer image processing techniques to extract cracks, the cracks were on the fractal images study. The paper used fractal geometry to describe the distribution of fiber-reinforced asphalt concrete cracks, and the establishment of the fractal dimension and fiber asphalt concrete stress relationship. At the same time, using fractal dimension of the fiber asphalt concrete cracks inhibit development of quantitative analysis. To obtain fiber modified asphalt concrete mechanism. It provided a new way to research the cracking mechanism and anti-cracking measures of fiber asphalt concrete. This paper got supported by the Hubei traffic science and technology project " Application Study on Polyester Fiber Asphalt Concrete ".