激光雷达探测建筑基坑开挖阶段气溶胶水平分布  

Aerosol Horizontal Distribution Detected by Lidar in Excavation Stage of Construction Site Foundation Pit

作　　者：赵强 苏红超 易明建 余东升 徐赤东 Zhao Qiang;Su Hongchao;Yi Mingjian;Yu Dongsheng;Xu Chidong(School of Environment and Energy Engineering,Anhui Jianzhu University,Hefei,Anhui 230601,China;Anhui Institute of Strategic Study on Carbon Dioxide Emissions Peak and Carbon Nestrality in Urban-Rural Development,Hefei,Anhui 230601,China;Anhui Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Hefei,Anhui 230031,China)

机构地区：[1]安徽建筑大学环境与能源工程学院,安徽合肥230601 [2]安徽省建设领域碳达峰碳中和战略研究院,安徽合肥230601 [3]中国科学院安徽光学精密机械研究所,安徽合肥230031

出　　处：《中国激光》2021年第20期133-141,共9页Chinese Journal of Lasers

基　　金：国家自然科学基金(41005016);民用航天预研项目(D040103);国防科技创新特区项目(DH863032001);安徽省高校优秀青年人才支持计划重点项目(gxyqZD2020036);安徽建筑大学科研基金(2020QDZ31)。

摘　　要：建筑工地扬尘等气溶胶是大气污染的重要来源,激光雷达是探测建筑工地基坑开挖阶段气溶胶水平时空分布的有力手段。一台532 nm波长的便携式微脉冲激光雷达发射激光并接收气溶胶颗粒与激光相互作用的后向散射回波信号,结合颗粒物浓度监测仪,利用Klett法和分段斜率法反演气溶胶水平消光系数和PM_(10)质量浓度。结果表明,用激光雷达探测的消光系数反演工地PM_(10)质量浓度是可行的。当基坑开挖、渣土外运等施工作业开始时,工地内的气溶胶颗粒浓度明显高于周边区域,且会向周边扩散;停止施工后,在无风情况下,气溶胶颗粒会聚集在工地区域内,PM_(10)质量浓度会维持在一个高水平阶段。研究结果为掌握并控制工地气溶胶颗粒排放情况提供了技术支撑。Objective The dust and other particulate matter generated during the excavation of construction site foundation pits are major sources of urban atmospheric aerosols and an important factor in the frequent occurrence of severe weather,such as haze.Aerosol particles on construction sites are derived from slag transportation and general construction dust,which are unorganized and irregular emissions.However,monitoring data in limited locations cannot fully and accurately reflect the spatial and temporal distribution of aerosol levels in the construction area.Lidar with high temporal and spatial resolution,large range,and real-time remote sensing monitoring capabilities has gradually grown into an indispensable observation device in the field of urban fine particle monitoring and atmospheric science research.Therefore,lidar is an effective method for detecting the spatial and temporal distribution of aerosols during the excavation of foundation pits at construction sites.Methods In this study,aportable micropulse lidar with a 532-nm wavelength emits the laser and receives the backscattered echo signal generated by the interaction between aerosol particles and lasers.Combined with the particle concentration monitor,the Klett and segmented-slope methods are used to invert the aerosol.The horizontal extinction coefficient and particulate matter(PM_(10))mass concentration are used to ensure that emission of pollutant particles in the entire construction site is always in a known and controllable state.First,a curve with distance as the abscissa and logarithm of the signal as the ordinate is obtained according to the lidar equation.Then,the least squares method is used to plot each small distance in the curve to obtain the linear equation of each distance,and its 1/2slope is the value of the horizontal extinction coefficient.The aerosol extinction coefficient of a certain distance with the highest correlation among the aerosol extinction coefficients at each distance is selected as the horizontal extinction coefficient at

关 键 词：大气光学 激光雷达 消光系数 气溶胶 建筑基坑 PM_(10) 质量浓度 

分 类 号：X831[环境科学与工程—环境工程]