elnaz baghernezhad

Urban form as the physical structure of the city, directly affects its ability in confronting natural disasters. Besides, as the spatial and physical presentation of human activities is the main context for various social, economic, and environmental aspects of urban resilience. Nevertheless, resilient urban form is still unknown in city resilient literature and despite the abundance of studies on urban resilience, research on the link between this quality and urban form is limited and fragmented. Resilience literature has defined resilient city charactresics and has set social, economic, infrastructural, institutional, environmental and community domains to achieve disaster resilient city. In order to understand how urban form can affect city resilience, this research based on resilient city characteristics, redefines urban form qualities such as robustness, redundancy, modularity, diversity, and efficiency as resilient urban form qualities. Thus, this study sheds more light on the relationship between urban form and resilience by assessing the relationship between these two phenomena to find out whether urban form can be one of resilience domains or only resilience domains can be affected by urban form’s components, based on explanatory, experimental and exploratory methodologies. The study area is Tehran metropolis and explicitly focuses on its 368 Neighborhoods. For this purpose, first, community disaster resilience in Tehran metropolis is assessed. In this regard, a set of resilient indicators extracted from three evaluation models (BRIC، CRI و CDRI) were used to evaluate and construct a resilient composite index for Tehran metropolis. By using exploratory factor analysis, the resilience dimensions are shown in four social, infrastructure, economic performance, and community domains. Second, urban form components are evaluated in the scale of a neighborhood, explaining six factors of denseness, green and vacant area accessibility, non-permeability, retail accessibility, plot accessibility and transit accessibility. Then, to achieve the main objective of this research, evaluation of the relationship between urban form and resilience, structural equation modeling (SEM) are applied. Therefore, in the present study, to find the relationship between resilience and urban form, two structural equation models are designed in AMOS software and analyzed by path analysis method. In the first model, urban form and resilience were considered as hidden variables, each of which was introduced based on its respective components and dimensions. As this relationship wasnot significant, the urban form cannot be considered as one of the dimensions of resilience. Then, the relationship between the components of the urban form and the resilience dimensions in the second model was analyzed to obtain the relationships between them. The results show that (1) none of the urban form components has significant effect on community resilience, (2) urban form components play different roles on various domains of urban resilience, in which denseness component as a major component of urban form has positive impact on infrastructure resilience but access to plot has significant impact on social resilience as a main domain of resilience. The other two urban form components such as transit and retail accessibility have positive impact on three social, infrastructure and economic performance. In sum, however urban form cannot be defined as an individual domain of urban disaster resilience, its elements and components have a significant impact on different aspects of resilience and resilient policies.

In recent decades, the question how we could reduce the frequency of auto mode and increase frequency of the other modes- walk and transit- is a challenged for urban planners. Many planning researchers and practitioners believe that individuals rely on automobiles partly to travel from place to place because land uses are separated and spread out. By contrast, when certain design features such as higher development densities and continuous sidewalks are combined with the mixed land uses, many expect residents of these communities to drive less and walk and bike more, on average. Tehran has been blamed for high levels of automobile travel and Traffic congestion, high travel time. So the primary purpose of this study was to investigate how relative associations between travel behavior and land use patterns where people live and non-work destination impact modal choice and frequency of travel modes in three different development patterns in Tehran. In fact this study wants to answer two questions: 1) whether patterns of travel behavior to non work destinations at neighborhood level are different? And a key question which is largely unanswered: 2) whether patterns of land development of neighborhoods affect travel behavior of residents? And particularly, whether pattern of neighborhood land development influences travel behavior or whether travel attitudes and preferences and socio-demographic characteristics influence travel behavior? In other words, whether differences in the built environment are associated with differences in travel behavior, after accounting for socio-demographic characteristics and for attitudes and preferences? More specifically, environments where residents are closer to destinations and have viable alternatives to driving are in fact associated with less driving. Here factor analysis, linear regression analysis are used to investigate the relationship between neighborhood characteristics and travel behavior while taking into account the role of travel preferences and neighborhood preferences in explaining this relationship. This study explored the relationship between the residential environment and non work travel frequencies by auto, transit, and walk/bicycle modes. In fact, a multivariate analysis of cross sectional data in three different land development patterns of neighborhoods of Tehran-Monirye, Koye-Bime and Koye-Golestan shows that there are differences in travel behavior between neighborhoods. Koye-Golestan (as a car-oriented neighborhood) largely is influenced by attitudes in contrast to Koye-Bime (as a conventional neighborhood), and Monirye (as a traditional neighborhood) land use characteristics are mostly affect on travel behavior. In general, however the number of autos that residents have as a socio-demographic characteristics and auto pro-travel attitude as a travel behavior attitude index largely influence on travel behavior, distance to transit, land use diversity as well as destination accessibility as land use index significantly influenced frequency by travel modes to non work destinations in neighborhoods. Taken together, our results suggest that if cities use land use policies to offer options to drive less and use transit and non-motorized modes more, many residents will tend to do so.