Along with explosive growth of cities and complication of inner-city processes, the number of crisis and urban complication increases and as a consequence vulnerability increases too. Considering that the man is in the center of the vulnerability and encounter with crisis, and also urban spaces contain most of the population, noticing these spaces is of urgent importance. It should be noted that a natural phenomena will be disastrous if societies are in danger and then risks are going to change to natural-technological disasters. In this respect, making policies to reduce vulnerability of urban spaces against natural disasters, considering their accidental nature and the necessity of adopting right decisions and development of human knowledge and technology, analysis of vulnerable areas in cities are essential to present a vivid picture of consequences of disasters. The analysis and planning is the most effective and perhaps the best choice of management and urban planners to counter natural disasters, especially earthquakes.
Crisis is defined as a situation that occurs unexpectedly as a result of natural events and human actions, disturbs human life, and needs urgent and instant measures to be taken. In other words crisis is a situation which disturbs main systems and subsystems.The aggravating elements of crisis include lack of information, lack of proper decision and the lack of serious measures to encounter the problem. Planning process is an action taken by the government agencies, NGOs and the public to recognize and reduce the risks (risk management) and to manage operations to recover and rehabilitate damaged areas (crisis management). In the process they try to find the markers and analysis of integrated and coordinated use of available tools to prevent the crisis and if they occur counteract measures carry out to rapidly return the city to its normal condition. When a threat managed properly, a crisis can be prevented or its effects can be reduced or even can be changed into an opportunity. Each crisis often has a merit and it could be a failure too. The most important part of crisis management should be devoted to crisis prevention and preparedness for natural disasters meant to be directed at reducing the risks and vulnerabilities. However, in urban planning, lack of attention to the issue of crisis management and urban vulnerability against earthquakes is quite evident; However it must be emphasized that in most of the developing countries the capacities and capabilities of this knowledge it is being ignored in most of the cities in all regional and national levels in the country. In Iran, because of geological, tectonic, climatic and environmental features, natural hazards, particularly earthquakes, along with the growing trend of urban development and population, is considered as the most widespread concern in people's lives. The wide mapping of the relative danger of earthquake in Iran shows that most of the residential areas are at stake, and it is low in just some areas of the country. According to the National Ministry of Roads and Urban Research Plan, 50 percent of the urban populations live in the areas that have the highest risk of earthquakes
The study is applied and descriptive-analytic method was used to collect data from library and field data sources. To measure the vulnerability of urban spaces against earthquake, 15 scales were used in three constructive, planning, and natural types. Vulnerability Indicators Seismic Vulnerability of areas are can be assessed by Evaluating spatial multi-criterias including:
1-Vulnerabilities due to being away from outdoors
2-Vulnerability due to population density
3-Vulnerabilities caused by damage to the buildings
4-Vulnerability due to age and type of building structures and materials
5-Vulnerability resulting from separate parts of building
6-Vulnerability due to number of floors of the building
7-Vulnerability due to lack of proper access to the street network
8-Vulnerability due to slope
9-Vulnerability due to lithology
10-Vulnerability due to closeness to the fault
Having measured scale’s weight using multivariate analysis, the study tried to use Fuzzy Logic.
Results and Discussion
The results of the study showed that 30% of urban spaces made in Ahar city to counter earthquake, are increasingly vulnerable to it and they lack structural framework to manage earthquake crisis. Slums are of high vulnerability and historical areas of city center are categorized as of higher vulnerability areas. Therefore, it is necessary for management and organizations having in custody of urban planning, to carry out practical measures to reduce vulnerability of these areas.
Nowadays, the field of crisis management knowledge and expertise is associated with a wide range of fields. Knowledge-based crisis management is a combination of science, art and practice. Crisis management can be fruitful and provide multi-dimensional development opportunity for the region to create an accurate plan before the crisis. The earthquake is one of the most common natural hazards that threaten urban spaces. In other words, the more the investment for developing and improving the foundation of a society, the less negative consequence and accidents would be. One of the most common dangers of natural disaster is earthquakes which threaten the urban areas. The crisis resulted from earthquakes caused researchers to plan and design strategies for crisis management to reduce its detrimental effects. In recent years, the knowledge of urban planning regarding its use attempted to find ways to reduce earthquake damages in cities which are main habitats of humans. The criteria and factors leading to vulnerabilities of the cities are common, to a large extent, in all cities, for instance accessibilities of houses to open spaces is effective in vulnerabilities. So identifying and localizing these criteria in a case study is considered as the main unit of analysis in the current process of urban planning. The process of planning and principles of urban design should be in terms of two overall program, crisis prevention and crisis mitigation.Offered Measures and policies controls and leads the dimensions and quality of urban development, should have policies and special measures to prevent the crisis and reduce vulnerabilities