Zoning Seismic Risk Areas of the Shiraz Gas Company Regions with Passive Defense Approach Using GIS and AHP Model

Abstract

One of the critical passive defense measures associated with gas installations, is examining the susceptibility of these facilities and identifying their vulnerabilities in critical situations, therefore we may minimize the damage from potential damages. This study intended to investigate the Zoning seismic risk areas of the city gas regions with passive defense approach using GIS and AHP model. The aims of the present study were: 1- Studying the principles of Passive defense (Location, camouflage, dispersion, hardening, strength, etc.) of gas installations 2- Zoning limits of vulnerability identification and gas facilities from the perspective of passive defense, and provide solutions to reduce the vulnerability of areas of gas facilities and gas installations of Shiraz when faced with the threat of earthquakes. For this purpose, to achieve the first objective, all sensitive installations important in terms of defense principles were studied. And in order to achieve second objective, to prepare the hazard zoning map7 Effective measures included: The distance from the epicenter of the earthquake, distance from the fault, geology, height, depth to groundwater, slope and aspect components were mapped in GIS, weighted and overlaid. Finally, the area was zoned based on the priority level of risk to 5 districts. The results showed that: a complete revision in gas installations in terms of the principles of passive defense, especially in terms of strengthening the fortifications to be should done. In terms of risk based on the AHP model, Shiraz surface level is of 7, 17, 27, 28 and 22 percent in areas of very low risk, low risk, medium risk, and high risk and too much risk. Based on the AHP model, were gas zones 1, 2, 3 and 4 respectively. The field observations and documentation of assessment models in the gas company indicated that the AHP model has good performance regarding earthquake hazard zoning in the studied area