关键词: 道路工程；随机骨料模型；骨料边界效应；骨料密度分布曲线；数值模拟技术；图像处理技术

Abstract: In order to study the aggregate boundary effect inside concrete components, the influence rule of real aggregate distribution, shape, length to diameter ratio, particle size, and number of surface edges and corners on the density distribution curve and boundary effects of aggregate was analyzed by image recognition technology and random aggregate modeling technology respectively. The research results show that the aggregate density distribution curve shows a pattern of first rising, then falling, and finally stabilizing or slightly oscillating, and is not affected by the geometric shape of the aggregate. When stable, the corresponding density fraction is slightly higher than the average aggregate density fraction. The peak thickness of aggregate density curve is approximately the minimum particle size of the aggregate, the thickness of the boundary effect layer is about the average particle size of the aggregate, and both gradually increase with the increase of aggregate particle size and length to diameter ratio. Among the geometric characteristic factors of the aggregate, the particle size of aggregate has a significant impact on the density distribution curve, peak thickness, and effect layer thickness, with a stronger degree of influence than other geometric characteristics.

Key words: highway engineering; random aggregate model; aggregate boundary effect; aggregate density distribution curve; numerical simulation techniques; image processing techniques