【作者】 李敏；

【导师】 殷杰；

【作者基本信息】 华东师范大学 ， 自然地理学， 2022， 硕士

【摘要】 在全球变化和快速城镇化背景下,城市地区极端暴雨洪涝灾害频发,“逢雨必堵”成为常态。急救医疗服务作为保障人民生命安全的特殊行业,对时间极为敏感,因此极易受到暴雨洪涝灾害的影响。老年人、儿童作为高脆弱人群,对急救医疗服务需求较高,暴雨内涝造成的交通延误甚至瘫痪无疑加大了脆弱性人口的受灾风险。因此,如何定量评估城市暴雨洪涝灾害对高脆弱人群急救医疗服务的影响已经成为当前洪涝灾害研究领域的重要课题。本研究选取上海市中心城区内高脆弱性单元(养老院)为研究对象,基于二维水动力模型Flood Map-Hydro Inundation 2D开展了不同重现期下的暴雨内涝淹没模拟,结合“淹没深度-速度”曲线,构建了暴雨内涝下的城市交通网络,采用Arc GIS网络分析等方法开展研究,从距离成本、时间成本和经济成本三个方面,揭示了暴雨内涝对高脆弱人群急救医疗服务的影响。主要结论如下:(1)在城市暴雨内涝特征分析的研究中,基于二维水动力模型开展不同重现期暴雨洪涝淹没数值模拟,根据模拟结果提取道路积水深度,以阈值“30 cm”设置道路通行状态,构建暴雨内涝交通网络危险性分析。结果表明:随着重现期的增大,淹没深度和范围不断扩大;5年、20年、100年暴雨内涝情景下研究区内中断路网占比分别为0.3%、1.6%、7.5%,中断道路分散分布在研究区域内。(2)在中心城区暴雨内涝交通模拟研究中,通过高德地图“路径规划”功能间接获取常态(晴天)实时通行速度,并基于“淹没深度-速度”曲线构建暴雨内涝情景下中心城区交通路网。结果表明:常态平峰和高峰时段道路平均速度分别为24.3km/h、20.9km/h,中低强度暴雨(5年、20年)对研究区内高速路、快速路的影响比较明显,百年一遇暴雨事件导致研究区内各等级道路速度下降20%-47%。(3)在暴雨内涝对高脆弱人群急救医疗响应的研究中,基于Arc GIS路网分析模块中的服务区分析,计算急救中心8,12,15分钟的服务区域;统计不同暴雨强度下急救医疗中心服务范围内各类高脆弱人群的数量和百分比,评估脆弱性人群的洪水风险;以高脆弱性单元(养老院)为研究对象,基于路网分析模块中的“最短路径”分析,确定急救中心-养老院的最短路径以及响应时间。结果表明:常态平峰时段急救中心在15分钟内基本可以覆盖全部区域;随着重现期的增大,急救中心的服务面积、脆弱性人群急救医疗服务的可达性以及高脆弱单元的响应时间也都表现出明显的非线性变化。(4)暴雨内涝对高脆弱人群急救医疗服务影响的研究中,通过Arc GIS路网分析模块中的“寻找最近设施点”确定“急救中心-养老院-医院”时间成本最短的路径,计算暴雨内涝情景下养老院急救医疗服务的距离成本、时间成本、经济成本。结果表明:中心城区养老院、医院、急救中心的分布较集中,近一半养老院在常态下急救医疗服务的距离成本小于3km,5年、20年暴雨造成养老院急救医疗服务路线被迫改道的几率较小,百年一遇暴雨导致急救距离最大延长了16km。常态平峰、高峰时段获得急救医疗服务的时长分别是22分钟、24分钟,当高峰时段遇及百年一遇暴雨,医疗服务时间成本延误最多达67分钟。急救医疗服务的经济成本和距离成本分布具有一致性,百年暴雨事件导致位于外环边界的部分大规模养老院的间接损失超过10万元。更多还原

【Abstract】 In the context of global change and rapid urbanization,pluvial flash flood(PFF)disasters in urban areas are frequent.As a particular industry to ensure the safety of people’s lives,emergency medical services are susceptible to time,so they are highly susceptible to the impact of the pluvial flash flood.As a highly vulnerable group,the elderly and children have a high demand for emergency medical services,and traffic delays and even paralysis caused by the pluvial flash flood undoubtedly increase the risk of disasters for vulnerable populations.Therefore,quantitatively assessing the impact of the urban pluvial flash floods on emergency medical services for highly vulnerable people has become an important topic in flood disaster research.Based on the two-dimensional hydrodynamic model Flood Map-Hydroundation2 D,this study selects the high-vulnerability unit(nursing home)in downtown Shanghai as the research object and simulates the pluvial flash flood under different reproduction periods combined with the "flood depth-speed" curve,constructs the urban transportation network under the pluvial flash flood,and uses Arc GIS network analysis and other methods to carry out research,from the three aspects of distance cost,time cost,and economic cost.The impact of the pluvial flash flood on emergency medical services for highly vulnerable populations was revealed.The main conclusions are as follows:(1)In the study on the characterization of urban pluvial flash floods,numerical simulations of storm flooding under different scenarios are carried out based on a twodimensional hydrodynamic model,and the depth of road water is extracted from the simulation results,the threshold value "30cm" is used to set the road traffic condition and to construct a hazard analysis of the flooded traffic network.The results show that the depth and extent of inundation increase as the return period increases;the percentage of disrupted road networks in the study area is 0.3%,1.6%,and 7.5%for the 5,2,0 an100-yearar storm inundation scenarios respectively,with disrupted roads scattered throughout the study area.(2)In the pluvial flash flood traffic simulation,the real-time traffic speed is indirectly obtained through the "path planning" function of Auto Navi Map,and the traffic road network in the central urban area under the pluvial flash flood scenario is constructed based on the "inundation depth-speed" curve.The results show that the average speed of the road during normal peak and peak hours is 24.3km/h and 20.9km/h,respectively,and the impact of medium to medium intensity rainstorms(5 years and 20years)on the highways and expressways in the study area is more obvious,and the speed of roads of all levels in the study area is reduced by 20%-47% due to the rainstorm event in the 100 years.(3)In the study of the emergency medical response to pluvial flash floods to highly vulnerable people,based on the service area analysis in the Arc GIS road network analysis module,the service area of the emergency center of 8,12,15 minutes was calculated;the number and percentage of various highly vulnerable people within the service range of the emergency medical center under different rainstorm intensities were counted to assess the flood risk of vulnerable people;the high vulnerability unit(nursing home)was used as the research object,and the shortest path and response time of the emergency center-nursing home were determined based on the "fastest path".The results show that the emergency center can basically cover the entire area within 15 minutes during normal peak hours,and with the increase in the recurrence period,the service area of the emergency center,the accessibility of emergency medical services for vulnerable people,and the response time of high-vulnerability units also show obvious nonlinear changes.(4)In the study of emergency medical services for highly vulnerable people to pluvial flash floods,the path with the shortest time cost of emergency center-nursing home-hospital was determined by "Finding the nearest facility" in the Arc GIS road network analysis module,and the distance cost,time cost and economic cost of emergency medical services in nursing homes under the scenario of the pluvial flash flood were calculated.The results show that the distribution of nursing homes,hospitals,and emergency centers in the central urban area is more concentrated,nearly half of the nursing homes have a distance cost of less than 3km of emergency medical services under normal conditions,and the probability of uninterrupted emergency medical services in nursing homes caused by heavy rains in 5 years and 20 years is small,and the distance cost is extended by 16 km under the scenario of rainstorms in a hundred years;the duration of emergency medical services during normal peaks and peak hours is 22 minutes and 24 minutes,respectively,when the peak hours encounter rainstorms once in a century.The cost of medical service time is delayed by up to 67 minutes.The economic cost and distance cost distribution of emergency medical services are consistent,and the indirect loss caused by the delay of large-scale nursing home emergency services located at the outer ring border caused by the centenary rainstorm event exceeds 100,000 yuan.更多还原