Assessment of urban areas based on physical resilience indicators: A case study of Historical fabric of Shiraz city

ABSTRACT
In recent decades, with the increase in risks and disasters, the need to enhance the resilience of communities has become more important than ever. One important aspect of resilience and crisis management in urban areas is the physical resilience dimension, which systematically evaluates the elements and physical structures of the urban fabric. This research aims to answer the following questions: 1. What are the influential indicators in enhancing the physical-spatial resilience of urban fabrics against natural hazards? 2. In what condition is the historical fabric of the city of Shiraz in dealing with natural hazards (especially earthquakes) based on these indicators? In this regard, the present study focuses on the historical fabric of the city of Shiraz using a descriptive-analytical method, applying a practical approach and utilizing a case analysis method by collecting data through library research, documentation, and Delphi questionnaire to examine the historical fabric of the city of Shiraz. The results of the data evaluation indicate that the building typology, age, and quality of structures have the greatest impact on reducing the resilience of the historical fabric of Shiraz, while land use, parceling, and mixed-use have the least impact. Overall, the analyses show that the historical fabric of Shiraz is at a moderate level of physical resilience, and deterioration and decline in environmental quality are relatively different within the fabric, such that the northern, southern, and southeastern parts of the region face more physical problems. Considering crisis management and the analyzed indicators, establishing emergency transport infrastructure, enhancing the quality of local governance in the area, providing services to the depths of the urban fabric, improving the quality of local management, and creating necessary grounds for neighborhood groups' collaboration for neighborhood-focused reconstruction are the main strategies and solutions to maintain and enhance the resilience status in the historical fabric of the city of Shiraz.
Extended Abstract
Introduction
Urban centers face critical challenges in planning due to rapid growth, climate change, and natural hazards. Key concerns include sustaining equitable quality, mitigating hazard impacts, structural-functional mismatches, and degradation threatening housing. These issues are acute in Shiraz, Zagros region, Iran, with 34 major faults (25 active) and significant historical heritage Therefore, this research aims to answer questions like: 1) What are the influential indicators in making the physical-spatial dimensions of urban structures resilient against natural hazards? 2) In what condition is the historical fabric of Shiraz city when confronted with natural hazards (especially earthquakes) based on these indicators? Evaluating the current state of resilience components in the form of drawing a physical-spatial pattern in the fabric, it aims to enhance resilience and increase its vulnerability levels.
 
Methodology
This research, using a descriptive-analytical approach, practically investigates the historical fabric of Shiraz City by collecting data through library research, documents, and Delphi questionnaires. By combining quantitative and qualitative data and employing Analytic Hierarchy Process (FAHP) as an efficient method in managing and analyzing complex multidimensional issues in Expert Choice software, and Delphi method with the opinions of 15 experts familiar with the region to determine the weights of the indicators, as well as using data network analysis in ArcGIS environment to evaluate different levels of physical resilience through indicators such as structure type, number of floors, morphology, age of buildings, permeability, building quality, land use, access to medical and emergency centers, access to urban green spaces, and mixed land use, a comprehensive image of the level of physical resilience of the historical fabric of Shiraz city is presented.
 
 
 
Results and discussion
The historical fabric of Shiraz city, relative to the context it is placed in, possesses attractions and special potential for guiding investments and accepting special activities to enhance resilience levels in various dimensions, especially the physical dimension. Key attractions include geographical centrality, convenient access, cheap labor force, specialized zones and sectors, traditional markets, historical-cultural structures, religious centers like Shahcheragh, population attractions, active centers, and more. However, alongside these advantages, there are negative features and deterrents, such as unsuitable physical conditions, lack of demand for many residential units leading to their abandonment, settlement of marginalized groups and non-native migrants with social issues, high traffic volume and inadequate services on main region roads, insufficient suitable spaces for market development and related facilities, lack of urban services and equipment especially parking facilities, inadequate access to wide areas of the fabric, decline in citizens' mental quality, and negative perceptions towards the fabric. These factors, along with economic aspects, have significantly impacted the physical-structural quality levels of the fabric over time.
After analyzing the resilience status of the research indicators separately based on the obtained weights for each indicator using Expert Choice software and with the help of ArcGIS software, the results of data evaluation indicate that the structure type, age, and building quality indicators have the most significant impact with weights of 0.254, 0.175, and 0.158, respectively, while land use, morphology, and mixed land use indicators have the least impact with weights of 0.38, 0.35, and 0.33 in reducing the resilience of the historical fabric of Shiraz city. As evident, physical issues in the historical fabric of Shiraz City are a central and general concern, with degradation and its associated factors present in various parts of the region. Analyses suggest that although physical degradation and low quality in the historical-cultural fabric are general issues, differences are observed within the region, with certain areas like the northern, southern, and southeastern parts facing more challenges than others. Overall, various data analyses suggest that the historical fabric of Shiraz City stands at a moderate level of physical resilience.
 
Conclusion
Considering crisis management and the analyzed indicators in this research, the main strategies and solutions for maintaining and enhancing resilience in the historical fabric of Shiraz city focus on redistributing, establishing and strengthening biological services, and increasing residential environment capacities in the region. These include setting up emergency transportation and emergency services, providing services to the depths of the fabric, improving local management quality, and creating necessary frameworks for neighborhood groups to cooperate in neighborhood-based reconstruction efforts. The analysis suggests that one of the most critical and common challenges in historical areas, especially in the historical fabric of Shiraz city, is gradual decline and degradation, which has left a significant portion of the region deteriorated and neglected. Thus, macro strategies in this regard emphasize urban renewal with a focus on active constructional changes by strategies such as creating physical-social-economic environmental bases, emphasizing cultural-artistic aspects over other intervention tendencies, restoration and cultural promotion of the ancient fabric by emphasizing a shift in activities, especially in the northeastern and southern parts, towards cultural-leisure approaches, creating attractions, authenticity, and differentiation at the city scale. Moreover, the necessity of developing residences and enhancing support services and infrastructure considering the unique capabilities of the historical fabric is emphasized, so that the existing facilities and capabilities in the historical fabric can also expand alongside their rival fields in areas like installations, services, infrastructures, and social security. Lastly, considering crisis management and the analyzed indicators in the primary research, the main strategies and solutions for maintaining and enhancing resilience in the historical fabric of Shiraz City focus on redistribution, establishing and strengthening biological services, and increasing residential environment capacities in the region, such as building emergency transportation and emergency services, improving local management quality, and creating necessary grounds for neighborhood groups to collaborate on neighborhood-oriented reconstructions.
 
Funding
There is no funding support.
 
Authors’ Contribution
Authors contributed equally to the conceptualization and writing of the article. All of the authors approved thecontent of the manuscript and agreed on all aspects of the work declaration of competing interest none.
 
Conflict of Interest
Authors declared no conflict of interest.
 
Acknowledgments
 We are grateful to all the scientific consultants of this paper.