Research On Regional Evacuation Management Under Flood Disaster With Evacuation Network Failure

Flood disaster is a kind of natural disaster,which is very common and in a high mortality rate,and many ordinary weather(such as rain and snow),or other disasters(hurricanes,tsunamis)will lead to floods,while floods may also lead to other secondary disasters such as flash floods and debris flows.With high frequency of its occurrence and long duration,floods may cause a huge economic loss.The U.S.NWS report shows that there are about 107 people are killed in the floods every year,in the USA alone,and in which nearly half are drowned on the flooded road in their cars when they fled out of the flooded area.We cannot prevent disasters from happening,but it can only be possible to reduce the losses disasters caused.Large-scale emergency evacuation increasingly becoming an effective way of scientific prevention and proactive hedging disasters.The purpose of evacuation management is to integrate various resources and take advantage of known information to use in evacuation activities,including design and planning for preand early flood evacuation strategy and evaluation of the evacuation various stages.Following the outline of an issue presenting,evacuation demand forecasting,evacuation road network service supplement,evacuation strategy,and case study of the research,we will focus on the evacuation demand changing caused by individual evacuation decision-making behavior,road network service capability changing caused by network failure,as well as evacuation route planning with time limitation,the three part studies.Firstly,from the view of the evacuation traffic demand,to analyze and discuss the individual evacuation decision behavior,based on the intellectual,social and environmental factors effective,to build a CRPV model to describe evacuation decision choice behaviors of differential individuals.By number the individual risk perception to find out the micro decision-making behavior of evacuees,to answer the question who will participate the evacuation activities,how many people need to be evacuated,how big scale traffic flow it will produce on the evacuation road networkSecondly,from the view of the supply,take the evacuation road network as the study object,bringing the study of destroy-resistance in the field of information into the study of analyzing the failure mechanisms of evacuation road network,to explore how to ensure its service capabilities when some node or segment failure occurs on the evacuation road network,to determine which node or segment causing the cascade failure of the evacuation road network,and to build a strong invulnerability evacuation road network strategy under the limited road conditions.Thirdly,based on the evacuation demand forcasting and evacuation road network design,applying CTM theory,take minimizing the evacuation system time(including network clearance time,duration time on the route and average evacuation time)and maximizing the number of evacuation veichles under the limitation of time as the planning object to set up a multi-objective evacuation route planning model,in order to make a safe evacuation strategy for guaranteeing the safety and celerity of evacuation activites,under different demand in different phase on the certain evacuation road network.Finally,take the basic road network in Harbin to be the real case,and make an application analysis of an emergency evacuation planning example under flood disaster scenarios.Based on the number and structure of population in the evacuation zone,number of veicles to certain the volume producing to the evacuation zone in different phase,determing the key note and segment of evacuation network based on the topology and historical flow volume,and by removing the key note and segment or making additional route for them to build a new evacuation network,applying multi-objective evacuation route planning model to set up a regional road traffic evacuation strategy for Harbin under a flood scenario.The Harbin road evacuation strategy can cope with a small-scale evacuation and a wide range of urban resident emergency evacuation due to the flood as a result of the water level of the Songhua River rises over a dam cordon.Supply a scientific basis of the theory and practice of learning for the future floods emergency evacuation planning and implementation.In this paper,based on relevant research results at home and abroad,by investigating and statistics,behavioral analysis,and optimization modeling,from the perspective of disaster evacuation demands,to study the key issues of evacuation decision-making selection of evacuating individuals under disaster conditions,and from the perspective of supply,to study how to content the evacuation demand by structure and capacity,and identify the key points of the network,from the perspective of building network construction to protect network,to improve the invulnerability of an evacuation road network.It is a novel work at the theoretical level and there are some contributions in improving the city's emergency management practice level,and urban and regional disaster response.