Zoning the degree of vulnerability of Semnan city infrastructure with passive defense approach In Geographic Information System (GIS)

Today, infrastructure plays a crucial role in the safe process of a society, and maintaining the security of infrastructure against attacks and threats is one of the security priorities of any country. Accordingly, recognizing the current situation and the vulnerability of infrastructure on an urban scale can lead to the development of urban strategies as an effective solution. In this regard, the present article uses a descriptive-analytical method, after collecting the required data and information, to explain the vulnerability of Semnan infrastructure with a passive defense approach using GIS, in which after prioritizing the centers of gravity And the identification of critical and critical infrastructure, the zoning of the city has been done using the process of network analysis and GIS. In this regard, the present article uses descriptive-analytical method, after collecting the required data and information, analyzes the infrastructure using multi-criteria evaluation methods, and after recognizing the interactions according to the spatial location of each infrastructure, the vulnerability of Semnan Calculated. The results show that a total of 37.83% of the infrastructure of Semnan city in areas with high vulnerability, 21.34% in areas with high vulnerability, 13.58% in areas with medium vulnerability, 14.66% in areas with very low vulnerability, 6% with low vulnerability and 12% with low vulnerability. They are under-established. This is far from the principles and considerations of passive defense and exacerbates the level of vulnerability.