Document Type : Research Paper
Authors
1
Associate Professor, Department of Urban Planning, Faculty of Art and Architecture, University of Kurdistan, Sanandaj, Iran
2
Department of Urban Planning - Faculty of Art and Architecture - University of Kurdistan - Sanandaj - Iran
3
Master student of Urban Planning, Faculty of Art and Architecture, University of Kurdistan, Sanandaj, Iran
Abstract
Occurrence of natural disasters, especially earthquakes in cities, leads to irreparable damage. So that planning to meet this challenge presupposes the transition from crisis management to resilience. Therefore, the purpose of this study is to measure and evaluate the vulnerabilities of Marivan city against earthquakes using descriptive-analytical research method. For data analysis, fuzzy model in ArcGIS software and network analysis process model (ANP) in Super Decision software are used. The results show that 170 hectares of the northern parts of the city (14% of the total area of the city) including neighborhoods 4, 3, 14, 15, 16, 17 due to high slope, texture fineness and long life of buildings and 121 hectares of parts East of the city (10% of the total area of the city) including neighborhoods No. 24, 25, 26, 27 due to the distance from service centers and lack of proper access to these services and proximity to the fault, along with 181 hectares of central texture (16% of the area The whole city, including neighborhoods No. 1, 2, 12, 13, 22, due to the small size and low physical quality of its buildings, has a moderate downward resistance to earthquakes and in case of its occurrence will be extremely vulnerable. According to the obtained results, it can be concluded that the status of resilience physical indicators in spontaneous settlements and dysfunctional northern and central urban areas in terms of physical indicators with 0.39% and eastern parts of the city including newly formed structures in terms of distance in terms of distance and service access indicators with 25 / 0% have much lower earthquake resistance than other parts of the city.
Extended Abstract
Introduction
Natural disasters that lead to disaster will have devastating economic, social, physical and environmental damage, so one of the most necessary measures and issues is to apply the principles of disaster management to prevent and reduce risks, preparedness, response and reconstruction and rehabilitation. In this regard, the physical and structural assessment of the urban environment is very important in terms of resilience to natural hazards, especially earthquakes.Over the past century, more than a thousand earthquakes have occurred in various countries, resulting in the death of millions of people and massive material damage. Statistics show that the western and central regions of Iran are one of the ten most fertile countries in the world due to the extent of earthquake-prone faults. As many cities in the country are vulnerable to it. And the city of Marivan in Kurdistan province is no exception to this rule.Marivan city with a population of 150,000 people is the third city in Kurdistan province in the northwest of the province with an area of 1387 hectares, of which about 350 hectares (25% of the total area of the city) is of low physical quality. . And according to the latest results of the 2016 census, about 34.5% of the total urban population has settled in this area. Also, due to the location of these tissues in informal and inefficient urban areas, the extent of their residents' access to service, welfare and medical uses along with the institutional performance of effective devices in providing these services and other similar cases compared to other parts of the city. It is not in a good condition. On the other hand, the short distance with the main faults due to the location of the city in the Sanandaj-Sirjan zone doubles the need to study and evaluate various indicators of physical resilience in the study area. Therefore, the purpose of this study is to study, evaluate and evaluate the physical indicators of urban resilience against earthquakes and provide solutions to increase the resilience of areas at risk of earthquakes.
Methodology
The research method is applied according to the purpose of the research and is based on descriptive-analytical research method. For data analysis, fuzzy method and network analysis process (ANP) have been used in Arc GIS10.8 and Super Decision2.1 software, respectively. In fuzzy indexes, different membership functions have been used to evaluate the values of each index. And in the ANP model, after the formation of the networked and weighted supermatrix, we form the normalized supermatrix for the 13 desired indices, and finally we obtain the final weights in the partial supermatrix. Then in the combined method of Fuzzy and ANP to investigate the current situation based on physical resilience indices (13 indices) resulting from theoretical foundations in ArcGIS10.8 software and using fuzzy model, the collected data are analyzed based on Small and Large membership functions, and the value of each We apply the indices using the opinion of experts in this field in ANP model and using Super Decision 2.1 software in the weight of fuzzy indices. Then, using the Fuzzy Overlay method, we obtain the total score indices in the physical texture of the city. In this method, the parts that have more points will have the highest level of physical resilience against earthquakes.
Results and discussion
As mentioned in the research process and method, according to the variables used in the proposed model and the data provided, we analyzed the physical resilience of the region based on fuzzy integrated model and network analysis process against earthquakes, which resulted in summarizing and overlapping fuzzy maps. Based on 13 indicators, it shows the northern parts of the city (including dysfunctional urban contexts and historical contexts and informal settlements) and the eastern part of the city, which includes neighborhoods with a rural background and annexed to the city, as well as southwestern parts of the city due to informal settlements. These areas have low physical resilience to earthquakes and will be highly vulnerable to earthquakes. The central and western texture of the city, including neighborhoods 1, 2, 6, 7, 8, 10, 12 and 13, due to compactness, fineness and organic texture, have moderate resistance to earthquakes, and this texture will also be vulnerable in the event of an earthquake. Neighborhoods Nos. 9, 19, 20, 21, 23 and 30 are in a better condition in the city and have a higher physical resilience against earthquakes than other areas. In general, the northern parts of the city due to high slope, texture fineness, number of floors, occupancy level and long life of buildings and low material resistance, eastern parts of the city due to distance from service centers and lack of proper access to these services and proximity to faults, central texture Due to the fineness of the texture, the number of floors, occupancy level and long life of buildings and low strength of materials and the southwestern part due to the formation of informal settlements and lack of proper access to earthquake resilience services and in the event of an earthquake is extremely vulnerable. They become tense. However, neighborhoods 6, 7, 8, 9, 19, 20, 21 and 30 are in a better condition than other neighborhoods and have higher physical resilience against earthquakes.
Conclusion
In general, the results of the study of 3 main dimensions of research indicators showed that in the field of distance and access to the main services of the eastern neighborhoods of the city (24,25,26,27,30) with 8250 people and an area of 304 hectares (22% of the area The whole city) due to the unrealizability of the per capita of the detailed plan, the annexation of rural lands in the strike plans to the city, the unbridled and unplanned growth in some parts of it from the point of view of this main indicator is not favorable. The texture of the central and northern neighborhoods of the city (15,16,17,14,3,4,12) with a population of 43,380 people and an area of 259 hectares (18% of the total area of the city) due to the old texture, instability of buildings, low occupancy level, Fine-grained and low strength of materials, especially in informal bios (17-16) are not in a good condition and have the lowest level of resilience. On the northern parts (neighborhoods No. 14,15,16,17,3,4) and parts of the southern part of the city (neighborhood No. 22) with a population of 49,200 people and an area of 279 hectares (20% of the total area of the city) due to the slope High and high density on these slopes d In times of crisis, especially earthquakes, it causes irreparable damage to these tissues. On the other hand, the proximity to the main faults in the west of the country doubles the severity of these damages, especially in these tissues and areas that were not in a good condition in other dimensions
Keywords
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