Study On Layout Optimization Of Fixed Refuge In Mountainous City Base On Disaster Risk Assessment

Disaster risk assessment is an important basis for city to formulate disaster reduction strategy and means of disaster prevention,disaster risk assessment can be evaluate where is high risk in city,then we take it in charge;urban emergency shelter is an important component of urban disaster prevention and mitigation,which can reduce losses and thereby reduce risk through reasonable layout.The research on disaster risk assessment is from large area of provincial level to small scale that urban community which closely related to residents 'life,and emergency shelters layout consider more and more factors,so research on layout optimization of fixed refuge in mountainous city base on disaster risk assessment is an comprehensive crossover study to them to perfect themselves,which not only assess risk in mountainous city but also consider disaster risk coefficient as an influence factor to fixed refuge layout.Study summary disaster risk assessment system that already published,then select and screen disaster risk assessment index base on disaster characteristics of Mountainous Cities and Likert-type Scale,decide the index of disaster risk assessment for small mountainous cities,AHP is used to construct the hierarchical structure model and determine the weight of each index.Secondly,using fuzzy comprehensive evaluation method and disaster mechanism expression R=(H(hazard)*V(vulnerability))/C(capability)to calculate comprehensive disaster risk value;last,study makes a comparative analysis of existing facility location optimization models,take the risk value as the weight coefficient,the multi-objective linear optimization function is selected to construct the multi-target location optimization model of mountain city,and take Dongchuan district as an example to case verification study.Disaster risk assessment results shows that disaster risk is high in Dabei village and Shiyang village in southwest and Tuanjie community Shengou village in central and Nuogutian village in northeast side;urban vulnerability is the highest in old urban communities,followed by surrounding administrative villages and last is new communities;fuzzy comprehensive risk value is high in Longtan village that disaster risk is high,Qiga village that lack of disaster prevention space,Saba community and Tuanjie community that urban vulnerability is on the high side.Present Situation Evaluation of Fixed Refuge Sites in Dongchuan District evaluation results shows wetland Park,peace square and stadium are located in unsafe area of the earthquake,landslide and debris flow and liquefied petroleum gas storage station,in addition,the other five shelters at present situation can not cover the whole area of Dongchuan concentrated residential areas;therefore,the multi-objective linear programming model is applied to optimize the layout of the existing shelters in Dongchuan district,and use Lingo programming software to solve the optimal layout scheme,solve out 10 as the optimum solution to layout of fixed refuges in Dongchuan District,which new-built five fixed refuges of third primary school,set up the road freight car park,the first primary school,washing and primary school base on five effective fixed refuges at present situation of bright moon middle school,fourth primary schools,the first middle school,the second middle school and Yunnan Institute of mechanical and electrical Dongchuan Campus.On the other hand,in consideration of the comprehensive utilization of the fixed place of refuge and multiple coverage problem of multi-objective model,we revise the results base on multi objective programming model that given the number of facilities and GIS,the correction number of facilities to meet the maximum coverage is 9,5 which include 5 current situation and 4 new venues,compared with the optimal scheme,the correction scheme delete rruck parking in Jiyi road.Taking Dongchuan district as an example shows that disaster risk assessment system that we construct is operable and meaningful;Multi-obj ective layout optimization model not only can take the risk assessment results into location optimization of refuge,but also provide a more efficient and economic program of layout optimization for city.