Research On Surface Damage Of Asphalt Pavement Based On Tyre And Road Interaction

Anti-slide performance is an important factor in the design of asphalt pavement, and reasonable character of asphalt pavement surface texture is one of the major aspects of the formation of anti-slide performance. Due to the friction and wear of the tire vehicle load after the roads were open to traffic, asphalt pavement surface texture disappeared gradually, leading to the reduction of anti-slide performance. People often use friction coefficient to evaluate the pavement anti-slide ability, but the index is macro and fails to reveal meso mechanism of decrease of the pavement anti-slide ability. Therefore, real asphalt pavement surface texture was chosen as the research object, considering the combination of pressure and shear effect, the wear rule of tyre load on the asphalt pavement surface texture was studied by numerical simulation and experiment from the meso level.The complexity of asphalt road surface texture will increase the difficulty of setting up finite element analysis model and makes it difficult to achieve the numerical calculation and analysis, so this paper studied the characteristics of asphalt pavement surface texture firstly. The height data was obtained through digital image processing technology and technology of three-dimensional reconstruction based on single image, then the self-similarity of asphalt pavement surface texture was studied according to self-similarity theory and the result shows that the asphalt pavement surface texture is self-similar. Based on this, fractal dimension is chosen as index to the character of asphalt pavement surface texture after comparing and analyzing the statistical parameters and fractal parameters which characterize asphalt pavement surface texture. The wear rule of asphalt pavement surface texture is reflected with the changes of fractal dimension.Secondly, local area was chosen to establish three-dimensional model with real rough surface according to the self-similarity of asphalt pavement surface texture. Taking the contact characteristics of mechanical behavior between the vehicle tire and road surface into consideration, the stress distribution rule on asphalt pavement surface for AC-13 and SMA-13 was discussed by ABAQUS under different conditions including different load amplitude, different operating conditions of vehicle; also,how the number of loadings influence the stress distribution of asphalt pavement was studied. Using the theory of maximum shearing stress as the damage criterion of asphalt pavement texture, fractal dimension was calculated to indicate the wear rule of asphalt pavement surface texture under different conditions mentioned above.Finally, the indoor experiment and outdoor investigation of actual asphalt pavement were done to find the influence of number of loadings on the wear of asphalt pavement surface texture.This wear rule is compared with the numerical simulation results and it is found that they are in good agreement qualitatively. The fractal dimension (D) diminishes exponentially with number of loadings (N) and the mathematics formula is D(N)=A+B×e(-β×N), in which A is fractal dimension after infinite friction and A>0, the sum of A and B is equal to the initial fractal dimension and β is attenuation coefficient which depends on many factors such as vehicle load and temperature and 0<β<1.