Abstract

Today, with the physical growth of large cities and increasing intra-urban travel, the issue of transportation and the achievement of an optimal spatial development pattern based on public transport are of great importance. In this regard, recognizing the structural and functional constraints of cities in the spatial distribution of utilities, services and population, how to balance the economic, social and physical capacities of the city with transport potential, can lead to favorable spatial development strategies. So, this paper, by analytical-exploratory method, explores and explains the structural-functional urban development based on the TOD system in the traffic area of Tehran. Library and field studies have been used to collect information. For data analysis, spatial information system methods such as optimal access index, inverted interpolation (IDW) and network analysis based on the weight overlay of layers have been used with ARC GIS 10.3 software. Research indicators also include population density, land use, user diversity, and use of activity centers and network capacity of the road. The research findings showed that despite the high capacity of Tehran's transportation system, it has 17 km of radial bus lines (BRT) and 41 stations; 38 km of subway lines and 40 stations; and 107 km of bus lines with 317 stations; Inappropriate. On the other hand, 63% of the scope of the Mobility Index is located in the "high" area. As a result, due to the distribution of inappropriate applications, people daily diverge intra-city trips to receive services from a variety of locations. As a result, it seems to be necessary to restrict the use of private cars, the withdrawal of inappropriate and incompatible uses, encouraging people to walk and bike, and to keep the population in range and prevent the change of residential usage. Extended Abstract Introduction: One of the most important forms of transportation planning and urban development is the emphasis on expanding the public transport system and guiding daily trips to utilize its capacity. This spatial development planning approach creates tight-knit, pedestrian-driven communities around high-quality freight stations, allowing for an increased quality of life without vehicle dependency. With the growing physicality of major cities and increasing urban travel, the issue of transportation and the achievement of a favorable spatial development model based on public transport is of great importance. Therefore, understanding the structural-functional constraints of cities in the spatial distribution of land uses, services, and populations, how to balance the economic, social, and physical capacities of cities with transportation potentials is desirable for designing spatial development strategies. Methodology: This paper, by analytical-exploratory method, explores and explains the structural-functional urban development based on the TOD system in the traffic area of Tehran. Library and field studies have been used to collect information. For data analysis, spatial information system methods such as optimal access index, inverted interpolation (IDW) and network analysis based on the weight overlay of layers have been used with ARC GIS 10.3 software. In this study, variables related to urban transport and factors affecting exacerbation of physical problems have been formulated. Research indicators also include population density, land use, user diversity, and use of activity centers and network capacity of the road. Initially, using population density indexes, institutions and economic centers, employment, land use, traffic volume and vehicle traffic at time and place; the traffic status and spatial flows of traffic in Tehran were studied using GIS techniques. Secondly, the BRT metro stations and accessibility index were calculated based on the standard access radius for each user, the distance between service centers and their access to the metro and BRT lines, and the mobility and range dynamics. And finally, using the layers produced in the previous steps and their evaluation and standardization, by examining and comparing public transport system patterns and spatial analysis, the extent of conformity of the range transport capacities with the TOD criteria of the study was. Results and discussion: Surveys show that Tehran has a population of about 8 million with a fixed population of about 4 million, with over 5 million cars and 15 million daily commute, with traffic and transportation problems particularly in the central city. Faces the limit of traffic plan. In this regard, the experiences of successful cities in applying the TOD-based transport system show that in Japan the emphasis is on cycling, public buses and city trains and in Brazil on the use of BRT express buses in the city center. Also, in downtown Amsterdam, the Netherlands, there is no bus or subway station, and cycling and special taxis are limited. On the other hand, according to the different models of transportation-centered design systems, it seems that Tehran's situation with TOD Corridor model is based on several types of transport lines (such as public bus, subway, BRT tram, etc.). And several distribution cores are more consistent. In this regard, the examination of the conditions of the transport system of the successful countries, especially the city of Amsterdam, showed that, in order to create a city with a transport-oriented and traffic-control system, the transport system with the main terminals, and the secondary and intermediate terminals with Design hierarchical relationships around the central part. And central control in the form of pedestrian and bicycle design and special and limited taxis. In this regard, in order to explain the conditions of the city of Tehran within the scope of the traffic plan and its compliance with the models and experiences of the successful cities, the existing situation and the transportation capacities were investigated. The results of the study showed that the transport capacity of the traffic plan area consisted of 35 kilometers of lanes with a width of more than 25 meters; 17 kilometers of BRT and 41 stations and 95 buses; more than 38 kilometers of subway and 40 stations. And 23 metro stations; and more than 107 kilometers of bus lines with 317 bus stops and 293 buses. However, this area is one of the busiest areas in the city and the traffic hotspots are in line with the metro route and BRT lines. According to the surveys, 63 percent of the space in the area of ​​mobility index is in the "high" zone. This shows that many residents in the area are also unable to access their needs from a convenient access distance. And to get multiple services, they need to travel long distances. Conclusion: Therefore, it can be said that many of the traffic and transportation problems in Tehran, especially in the area of ​​traffic planning, depend on the spatial distribution of land use and the proportionality between population and activity and service use. Also, the analysis of conformity of transportation capacities and land use pattern with TOD principles showed that Tehran city was not successful in terms of pedestrian, accessibility, cycling and spatial distribution of land use proportional to population capacity. For this purpose, according to the theoretical and analytical findings, the following requirements are necessary to achieve the criteria of the axle transport system: Restrict the use of private cars in the city's central loop and design of pedestrian / bicycle-based networks Spatial Distribution of Service and Business Users Based on Population Capacity and Transport Exit incompatible land uses and move them to areas beyond the city center or second layer landfills Protecting the population of the area and preventing