为深入研究水下特长公路隧道机动车尾气污染物的排放及分布特征，对南京应天大街长江隧道的交通特征、环境参数和污染物排放质量浓度进行实测研究。采用摄像采集法统计隧道交通特征，结果表明：
车辆交通数据与环境数据均呈现明显的日周期变化规律，早高峰车流量显著大于晚高峰，车速与车流量呈负相关。夜间测试结果表明： 1)隧道内部污染物质量浓度沿行车方向的变化趋势为先增后减，由于隧道呈现V形的地势特点，PM2.5质量浓度峰值出现在V形底部； 2)受到隧道出口风机开启的影响，CO质量浓度峰值出现位置较PM2.5稍有滞后。昼间测试时风机关闭，污染物质量浓度峰值出现在隧道出口，早高峰期间隧道出CO和PM2.5的质量浓度峰值分别为31.0 mg/m3 和145 μg/m3，分别为质量浓度限值的3.1倍和2倍。采用皮尔逊（Pearson）相关系数法对各相关参数进行相关性检验，CO质量浓度与汽油车数量呈强正相关，PM2.5质量浓度与柴油车数量呈强正相关，2种污染物质量浓度均与风速呈强负相关。
In this study, the traffic
characteristics, environmental parameters, and concentration of vehicle exhaust
pollutants of the Yingtian avenue in the Yangtze river-crossing tunnel in Nanjing, China, are examined to thoroughly
investigate the emission and distribution characteristics of vehicle exhaust
pollutants. The traffic characteristics are statistically analyzed using video-recording methods, revealing a distinct diurnal variation pattern,
with drastically higher traffic flow in the morning peak than the evening peak,
and an inverse relationship between vehicle speed and traffic flow. Night-time testing indicates that pollutant concentrations inside the
tunnel initially increase and then decrease along the length of the tunnel,
with the PM2.5 concentration
peaking at the bottom of the Vshaped terrain of the
tunnel. The CO concentration peak appears slightly later than the PM2.5 peak because of the influence of the
activated fans at the tunnel exit. During daytime testing, when the fans are
off, the pollutant concentration peaks at the tunnel exit. In the morning peak,
the maximum concentrations of CO and PM2.5 at the tunnel exit are 31.0 mg/m3 and 145 μg/m3, respectively, which are 3.1 and 2
times the concentration limits, respectively. The Pearson correlation analysis
conducted to examine the relationships between various parameters reveals a
strong positive correlation between the CO concentration and the number of
gasoline vehicles and a strong positive correlation between the PM2.5 concentration and the number of diesel
vehicles. Both pollutants are strongly negatively correlated with wind speed in
the tunnel.
