Optimal Strategy Research On Safety Evacuation Of Urban Residential Area In Northeast China

As the largest component of urban functions in area proportion,residential area is not only a place for residents to live,but also needs to provide the basic security for life and property.However,due to the lack of methodological guidance and obsolete theoretical research,urban planning practices in the early years of China were not integrated with the design methods for disaster prevention and mitigation,which resulted in the weakness of urban space to cope with the threat of major disasters,the inadequate emergency management and the potential safety hazards in the process of crowd evacuation.Benefit from the development of computer technology and the continuous research of basic theory,in recent years,scholars have begun to use simulation and quantitative research methods to explore disaster prevention at urban scale.However,due to the long-term neglect of this problem and technical limitations of data collection,current studies rarely focus on the correlation mechanism between residential area planning forms and crowd evacuation behavior.The spatial structure of residential area not only determines their ability to resist and reduce the impact of disasters,but also restricts the response mode and behavior of residents in emergency situations.In the last century,the urban development of northeast China had experienced the construction periods of colonial,industry base and the urbanization,which formed the diverse urban fabrics with different spatial patterns.The continuous enhancement of land use intensity and population agglomeration trend on the existing urban space brings great challenges to the disaster tolerance and emergency response ability of urban residential area.Based on the systematic study of the spatial features of residential area and crowd evacuation behavior,this research explores the rules between the design elements of residential area with different scales in northeast China and safety evacuation,proposes optimization strategies of residential area through the fields of urban planning,disaster rescue and emergency management in both quantitative and qualitative perspectives.In basic theoretical research,this paper analysis the common hazard types and regional disaster response features in northeast China,discusses crowd behavior psychology in the scenario of emergency evacuation and the internal relation between space and evacuation behavior,expounds the morphological connotation of residential area at urban and block scales and the spatial features of residential area in northeast China,defines the evacuation process and related planning elements of residential area.From the aspects of disaster prevention planning,disaster rescue and emergency management,the importance of disaster response capability to ensure safety evacuation of residential area are emphasized.According to the spatial elements of urban residential area and crowd evacuation routes,investigation method of residential area in northeast China and the evacuation simulation program are formulated,and the safety evacuation information model of residential area is constructed.Based on the random sample survey,the typical patterns of residential area at urban scale and block scale are obtained,relevant parameters of evacuation simulation are set,which lays a foundation for the evacuation simulation of urban residential area in northeast China and the acquisition of optimal strategies.The evacuation simulation platform based on agent-based model is used to realize the evacuation simulation of typical patterns of residential area at urban scale,and corresponding optimization strategies are proposed.At urban scale,road network and block form are taken as variables to obtain potential risks and high-risk trampling areas of whole evacuation process,as well as the congestion change rules of roads,blocks and road intersections based on the analysis of evacuation time and congestion situation.The obtained optimal strategies including reducing the density of road network and expanding potential congested roads,reasonably arranging rescue routes and distributing emergency supplies according to the evacuation characteristics of specific spatial structure,extracting the key data of location and time development of typical congestion points to guidance crowd diversion in vulnerable areas.In order to reduce evacuation risks of residential area at block scale,the evacuation of typical patterns at this scale are simulated,and the optimal strategies to ensure safety evacuation are proposed according to the evacuation simulation results and evacuation scenario information.Road network,block form,setting of exits and building layout are taken as variables at this scale to obtain the triggering mechanism of the corresponding planning elements on the evacuation characteristics,the evolution of evacuation and congestion time,and the distribution of congestion range.Based on the analysis results to put forward optimal strategies of setting buffer space,improving the capacity of congested exits,selecting rescue path and presetting rescue facilities according to the evacuation behavior of crowds,and deepening the snow cleaning plan at block scale by refining evacuation information and selecting congestion patterns to improve the emergency action capacity in disaster.This paper extracts the planning elements which restrict the safety evacuation of residential area from both urban scale and block scale,explores the morphological information of residential area and its significance to disaster prevention.The crowd evacuation disciplines of residential area from the factors of evacuation time and congestion performance are summarized,which expand the depth of discussion on the influence mechanism of residential area planning elements on safety evacuation.At the same time,the characteristics of evacuation under different conditions are organically connected with strategies of planning,disaster rescue and emergency management,which provide new research perspectives and technical solutions for improving the safety evacuation of residential area,and also contribute to the theoretical and practical innovation of residential area planning in northeast China.