عنوان مقاله [English]
نویسنده [English]چکیده [English]
Following the increase in population, especially in large cities and urban transformations recently, the use of underground space has been considered in many countries as a solution to urban problems. Underground space, as surfaces that placed in underlying layers of the ground, have various features and facilities. But so far from various features of underground space to solve the urban problems, only the physical aspects have been studied to solve traffic problems, whereas one of the main urban problems is vulnerability against crises and disasters. Therefore, studying about urban underground space development and recognition of its potentials on the one hand, capabilities and investigating the features of crisis management and effective actions in each step on the other hand can be considered for achieving a solution to reduce the vulnerability of cities against crisis. In this regard, reviewing literature, studying documents related to scientific reviews, studying examples of successful international experiences and poll of 35 experts in these fields and the result of questionnaires used in Delphi fuzzy model are used in order to investigate the relationship between these two issues. From the overlap of obtained criteria in each field and the result of poll of experts, proposed criteria for underground space development has been prepared in order to control crisis management. Research achievements indicate that developing the underground spaces can be very effective in reducing the amount of casualties especially in large cities. Hence, some of the major reasons for using underground space in improve performance of crisis management are effective in use of ground through moving some of incompatible land uses, considering the humanitarian relief bases and transferring urban facilities to the underground space, creating readability through use of signage, hierarchical motion, proper lighting, quite clear entries, maintaining the safety through preventing of the consequences of the crisis in underground space as well as the possibility of opening and closing on time of all input and output doors, creating a powerful air conditioning system, structural changes in urban facilities through creating the common tunnel installation. Improving access ways through improving ways that leads to underground space, creating extremist roadway as alternative ways in crisis situations, creating connection between critical uses, organizing the social participation for identifying black spots, attention to humanitarian needs through removing fear of exposure in underground spaces, special attention to vulnerable groups can also be effective. Reducing cost through moving the urban facilities to underground space, creating the insurance facilities for compensation for damages of crisis, preventing of damage to the environment through moving and burying disposal of hazardous waste in underlying layers of the ground can lead us to impressive results. There exist overlaps between criteria of underground space development and criteria of crisis management for more than 85 percent in physical field, about 90 percent in transportation field, about 75 percent in environmental field and about 70 percent in economical field. The maximum overlap between proposed criteria there exists in physical, transportation and environmental fields. Therefore creating the extremist underground ways and connected main humanitarian relief centers through underground space development in transportation field and using underground space for disposal of hazardous substances in environmental field is in full compliance with criteria of urban crisis management. Eventually it seems that it can be used for proposed criteria from developing the underground space with the present approach.