An analysis of the conflict between Passive Defense Requirements and Principles of Sustainable Urban Development in the improvement of urban historical fabrics Case study: Urban historical fabric of Tehran's District 12

Introduction Preservation and maintenance of historical urban fabrics or fabrics containing cultural heritage of cities is of special importance, because these fabrics, in addition to creating a sense of identity and stimulating national pride, improve the citizen’s quality of life. »Improvement«is one of the methods and, of course, the most appropriate one, of intervention in the historical fabrics of cities, because in this type of intervention, the principle is based on "loyalty to the past and the preservation of identity-stimulating effects".
Improvement activities are aimed at using available potential and actual facilities, strengthening positive aspects and weakening negative ones. In each of the improvement measures, no significant intervention is performedin the physical aspect, and only by replacing the proper functioning of activity the erosion of this type of urban space is prevented, and by making changes in urban activities, favorable urban spaces is created. Since the observance of the "passive defense requirements" as well as the "sustainable urban development principles" is an essential requirement in selecting the appropriate pattern for the improvement of the old urban fabric, the study of the principles governing these two concepts indicates thatcontradictions exist between these principles. In the present study, we have mainly studied and examined these two important and influential concepts on the improvement patterns of historical urban fabric, and carried out a comparative study of the principles governing them. The purpose of this research is to outline the contradictions between the requirements of passive defense and the principles of sustainable urban development in the improvement pattern of historic urban fabric and to find a suitable solution in this regard.
Materials & Methods The research method was applied in terms of the aim, and descriptive-exploratory in terms of conduct. The data gathering method was both documentary (secondary) and field surveys, and analyses were performed using the ArcGIS software and also by the Paired Comparison Analysis method. The historical fabric of the 12th district of Tehran, with an emphasis on the historical element of the museums, was the case study of this paper, which made it possible to achieve the results of the research. In order to prioritize some uses in positions where the studied historical element (museum) are located, from the point of view of passive defense as well as from sustainable urban development perspective, we can use the Paired Comparison Analysis method to achieve the most balanced result, So that the conflict between the two approaches is not significant. First of all, the importance of each single studied use is examined from either of the two perspectives through the spatial analysis ofthe position of that particular use relative to the location of the museums. Then, the view of passive defense concerning each use has been compared with that of sustainable urban development according to the relevant criteria, and scored on the basis of importance.
Results & Discussion The results of the research show that in order to find the most suitable pattern of intervention - of improvement type - in the historical fabric, it is necessary that along with emphasis on the requirements of passive defense and principles of sustainable urban development, We must, in addition to prioritizing changes in uses, reduce the grounds for the creation of any kind of contradiction in approaches. Therefore, in the present paper, the uses and elements affecting theregion have been analyzed in relation to the studied fabric (museums). In the investigated pattern, actions and predictions to improve the physical and environment through the replacement of proper operation of activity will prevent the erosion of the historical urban fabric, and by creating changes in urban activities, favorable spaces for the protection of historical fabric will be created.
Conclusion In spite of the proof of the conflict between "passive defense requirements" and "principles of sustainable urban development", the emphasis on both concepts in the improvement pattern of city’s historical fabric isinevitable.
Therefore, by adopting an appropriate model for improvement and appropriate methods of intervention, it is possible to perform the important task of preserving the historical fabric by optimally changing some of the uses.