随着工业化和城市化进程加快，城市大气污染受人类活动的影响更加深远。城市道路长度、机动车保有量逐年增加，道路扬尘污染作为城市粉尘释放的重要组成部分，对大气污染的贡献不可忽视。本文以北京市六环内典型道路为实验对象，结合车辆颗粒物浓度快速测量法和真空吸尘法，探讨道路扬尘颗粒物浓度与采样车辆速度及道路积尘负荷的相关关系，建立道路积尘快速检测模型，获取北京地区主要环路快速路、高速公路的道路积尘负荷分布情况。同时，对多个建筑工地周边道路进行道路积尘检测，并与以环路高速路为代表的北京市道路积尘负荷平均状态进行对比分析。最后，对裸土地表附近道路高积尘负荷特性、扬尘浓度与粉尘释放机制进行了探讨。本文的研究结果如下： (1)使用颗粒物浓度快速测定和真空吸尘法对实验道路进行道路扬尘颗粒物浓度及道路积尘负荷测定，建立道路扬尘颗粒物浓度与速度和道路积尘负荷的转化关系，最终实现北京地区道路积尘负荷的快速测定。 (2)对北京市环路及高速公路进行道路积尘负荷测定。结果表明，高速公路路面积尘负荷整体小于环路快速路；随与城市中心距离增加，道路积尘负荷逐渐减小；北京北部地区道路积尘负荷小于南部地区，东部地区道路积尘负荷小于西部地区。 (3)对北京市建筑工地周边路段进行道路积尘负荷测定。结果表明，工地周边道路平均积尘负荷超出环路和高速公路平均值的100倍以上，此类路段对道路扬尘排放的整体贡献率极高。 (4)施工直接粉尘排放及车辆渣土夹带遗撒是造成工地周边道路积尘负荷剧增的重要原因，其中车辆出入工地造成的裸土夹带和渣土遗撒对道路积尘大幅增加的影响更为显著。 (5)车辆重力作用、车辆机械扰动强度是影响道路裸土粒度的重要因素。当车辆碾压次数增加时，道路中土壤粒径整体减小；当道路土体质量增加时，车辆对土体的碾压破碎能力降低；而车辆碾压道路裸土的持续时间和车辆行驶速度是影响土体破碎能力的重要因素，两者叠加，共同影响土体破碎的总比例。 (6)污染源点的裸土重量、道路裸土粒度组成、车辆扰动强度是影响裸土扩散的重要因素。随车辆碾压次数增加，道路污染源点裸土扩散总量呈现先增大后减小的趋势，而道路裸土扩散质量比则持续增加；随车辆速度增加，道路污染源点的裸土扩散总质量和其质量比率均大幅提高。

With the high speed of industrialization and urbanization process, urban air pollution is substantially affected by human activities. The length of urban roads and the number of motor vehicles are increasing year by year, as a result, road dust pollution is gradually become an important part of urban dust emission, and its significant contribution to air pollution cannot be ignored. Taking typical roads within Beijing’s six rings as study object, and combined with rapid measurement method of vehicle particle concentration and vacuum cleaning method, this article focus on the relationship between the dust particle concentration of the road, the vehicle speed and the road silt loading, which is the foundation to establishment of the rapid detection model of silt loading. Using this method, the silt loading distribution of ring roads and highways in Beijing was obtained. At mean time, silt loading tests were conducted on roads around construction sites, as a contrast of the average state of silt loading represented by the Beijing ring roads and highways. At last, the high silt loading characteristics, dust concentration and dust release mechanism of the road near the bare land surface are discussed. The result of this article as follows: (1)The road dust particulate matter concentration and silt loading were detected on experimental roads in Beijing by rapid measurement method of vehicle particle concentration and vacuum cleaning method. As a result, the conversion relationship between road dust particle concentration and vehicle velocity on the road, and the conversion relationship between road dust particulate matter concentration and road silt loading were established. (2)Using rapid measure method to detect the actual silt loading on the Ring Expressway and highways in Beijing. The results show that the overall road silt loading on the highways is less than on ring roads. Starting from the city center, the road silt loading gradually decreases as the distance increases. The overall trend is that the road silt loading in the northern is less than that in the south, and the road silt loading in the east is less than that in the west. (3)Using the rapid measure method to detect the silt loading on roads nearby construction sites. The result shows that the average silt loading on these roads presents more than 100 times of the average silt loading of ring roads and highways, so the overall contribution rate of this kind of road dust emission is extremely high. (4)Direct dust emission from construction, vehicle-related deposition and spills from vehicle are important reasons for the dramatic increase of silt loading of roads around construction site, in which the effect of vehicle-related deposition and spills from vehicle are more significant. (5)Gravity and mechanical disturbance intensity of the vehicle are important factors affecting the particle size composition of the soil. When the vehicle rolling times increases, the soil particle size in the road decreases. The crushing ability of vehicle to soil gradually decreases with the increase of soil weight. Moreover, the duration of vehicle passing through the bare soil and the speed of vehicle are important factor influencing the crushing capacity, both of which affect the total particle size composition of soil. (6)Soil weight, particle size composition, and vehicle disturbance intensity are important factors affecting the diffusion of bare soil. With the increase of the number of vehicle rolling, the diffusion quality of bare soil at the road pollution source point first increases and then decreases, while the diffusion quality ratio of bare soil continues to increase. With the increase of vehicle speed, both the total diffusion quality of bare soil and the ratio above increased significantly.