重庆市典型道路微环境中的PM_(2.5)排放特征研究

Research on Characteristics of PM_(2.5) Pollution Emitted by Typical Road Traffic in Chongqing

选取重庆市大渡口区西城大道对道路微环境中PM_(2.5)、温度和湿度进行2周的自动在线监测,结合道路RFID基站的车流量及车型信息,分析了PM_(2.5)质量浓度与交通流变化特征及其相关性。结果表明:道路交通微环境PM_(2.5)日均质量浓度变化范围为18~34μg/m^(3),PM_(2.5)小时值基本呈现双峰特征。西城大道车日均流量12818辆/天,周末早高峰期间比工作日平均车流量下降约20%左右。PM_(2.5)质量浓度与小时总车流量具有一定的相关性,在白天时段(7:00-18:00),总车流量与PM_(2.5)小时质量浓度呈现弱正相关性,在夜间时段(19:00-6:00),总车流量与PM_(2.5)小时质量浓度呈现弱负相关性。

This study elects Xicheng Avenue,Dadukou District,Chongqing to conduct an automatic online monitoring of PM_(2.5),temperature and humidity in road microenvironment for 2 weeks.It combines with traffic flow and vehicle type information provided by road RFID base station to analyze the variation characteristics and correlation between PM_(2.5) mass concentration and traffic flow.The results show that the daily average of PM_(2.5) mass concentration in road traffic microenvironment ranged from 18 to 34μg/m^(3),hourly average of PM_(2.5) mass concentration basically presents a bimodal characteristic.The daily average traffic flow of Xicheng Avenue is 12,818 veh/d,during the weekend morning peak,the daily average traffic flow decreased by about 20%compared with weekdays.There is a certain correlation between PM_(2.5) mass concentration and hourly total traffic flow,during the daytime period(7:00-18:00),the hourly total traffic flow showed a weak positive correlation with PM_(2.5) hourly mass concentration;while during the night period(19:00-6:00),the hourly total traffic flow showed a weak negative correlation with PM_(2.5) hourly mass concentration.