monitoring of physical parameters and modeling for recognize areas need to replacement at the informal settlements (case study neighborhood of chahestaniha in the bandar-abbas city)

growing population and increasing urbanization has led to the expansion of informal settlements. informal settlements in developing countries, more than other urban tissues are exposed to various risks and natural disasters. this type of settlements, often develop and spread without regard to natural hazards, with no specific plan and no attention to regulations. expansion of informal settlements in the city of bandar abbas, has been causing problems for cities and urban management. one of the most important informal settlements in the city of bandar abbas is chahestaniha. in this study analytical hierarchy process (ahp) is used to determine zones which with a view to effective natural factors need replacement. first, effective natural factors were studied. then according to the weight of each factor, the map of these weights was prepared. in the next step, the vulnerability map, using layers of the weight and the weight coefficient of each factor is provided. afterward, the arc scene in the arc gis software was used to scrutinize areas that are in need of replacement. finally, after the field visits, using three-dimensional topography of the neighborhood and scrutinize the results, requiring replacement zones have been identified. the results of this study indicate that the northern and northeastern parts of the neighborhood, located within the high risk environment, and in case of danger, damage will be irreparable. factors such as, inappropriate construction, low resistance materials used in buildings and old buildings, narrow streets, on the establishment of constructions on detached and non-resistant elements of nature, high slope, and unstable hillsides near neighborhood in the eastern part , and the risk of mass movement, can intensify vulnerability of this neighborhood. accordingly, in the decision-making process leading to the preparation of plans for organizing this type of settlements, it is essential to consider the effect of environmental factors and morphogenesis phenomena.