عنوان مقاله [English]
Mass volume of traffic in city centers cause to some problems like traffic congestion and pollutions. Hence new movements such as Transit- Oriented Development (TOD) with emphasis on compact development, people-friendly and livable neighborhoods introduced as useful tool for reducing use of car. Wisely use of land around transit stations is one of best solutions to achieve objectives of this approache. According to distribution of urban uses, land use pattern has high influence on travel behavior of people. In fact the land use pattern by its different characteristics determines travel behavior of people. About this, Todd Litman introduces some factors sush as land use mixture, density and etc. as effective factors on sustainable travel behavior. In recent decades, Sanandaj's boundary and use of cars due to daily trips of people city has been increased. City center of the Sanandaj with high value in physical, social and cultural aspects today has considerable problems like traffic congestion that are mainly due to incompatible policies according to spatial and transportation planning. Therefore, this paper tries to evaluate important factors that are effective on trips mode of residents in center city of Sanandaj and want to present strategic recommandatios based on TOD criteria for achieving sustainable city center.
TOD approach presented by Peter Calthrope based on "pedestrian pocket" concept for facilitating spatial communications and consequently achieving high social and economic correlations. This approach relates to residential and commercial centers that designed based on maximum access to public transportation and non-motorized modes. Hence public stand (rail and bus station) will locate in central position and surrounded by dense developments to 800 meter radii then will decrease. Some of specialists have been citing that TOD projects can include variety of forms and station areas but are supplements in the system functionally. Reconnecting America and CTOD introduced eight forms of TOD including regional center, urban center, Suburban center, transit town center, urban neighborhood transit neighborhood, special use/employment district and mixed-use corridor.
2-2-Advantages and disadvantages of TOD
TOD, as one of the most visible forms of smart growth, is increasingly viewed as an antidote to traffic congestion, the isolation and detachedness felt in many suburban communities, affordable housing shortages, and inner-city decline and disinvestment. Evidences show that in development with more compactness, people 30 to 40 percent lesser use vehicles that has health and economic benefits. Also in this development, investments in public transportation due to increase of riderships, have more benfits for all stakeholders and provide accessibility for all. In addition, with developing pedestrian and bicyle routes and emphasis on green transportation with low level of air and noise pollutions, TOD can create livable communities. But some of specialists believe that TOD planning, derived from beautiful urbanism that without attention to social behavior, emphasis on physical design. Deficit of advocacy legal bases, high cost of primary financing, dependency on people tendency and low investments from investors and lenders are other barriers for TODs.
2-3-Land use management and urban transportation
Between Land use pattern and Travel behavior exist near relationships. As land use planning by impact on distances between origin and destination, emphasis on decreasing trips. Planners present different factors that affect on mode choise of resident. Cervero (1989) believs that level of density, land use mixture and design of site have maximum impact on transportation factors like pollution emission, vehicle mile of travel (VMT), fuel consumption and car ownership. Todd Litman (2012) consider different factors such as Density, Mix of uses, Regional Accessibility, Centeredness, Connectivity, Roadway design and Management, Walking and Cycling conditions, Transit Accessibility, Parking supply and Management, Site design and Transportation Demand Management (TDM) as important factors. Some land use management strategies are introduced for achieving integrated planning. One of these is TOD strategy that wants to decreasing ownership and car use by locating residential and commercial building near transit stations with joint development.
For assessing land use factors in city center of Sanandaj, based on TOD planning principles, transit center of Naser-Khosro has selected and 600 meters radii area around the transit center has evaluated that contains 101 hectars.
3-1- Assessing land factors in study area based on the Litman pattern
In this stage, the study area is identified based on above factors. Main factors include dominance of private car movement, relative mix of uses, high density of residential and commercial unit relatively, low connectivity of routes, deficit of accessibility and low quality of services of buses, large lots parking near the station and lack of roadway design.
3-2-Assessment of condotions with SWOT analysis
SWOT as evaluation method has useful results in urban studies. In this stage of research, positive and negative qualities of the study area will evaluate based on four dimentions of SWOT and Litman factors. In fact, the evaluation is a basis for strategy presentation.
3-3- Determinig priority of factors
For achieving best results in providing strategies, effective factors are prioritized. Priority of each factor calculated by urban planners and transportation specialists so that priority of them combined in Expert Choise software based on AHP method and final prioprity achieved as shown in the following table.
Mix Density Connectivity Regional Accessibility, Centeredness Walking and Cycling conditions Public transportation Parking management Site and roadway design TDM Factor
0.66 0.72 0.69 0.36 0.123 0.266 0.102 0.071 0.195 priority
According to above table, Transit Accessibility, Walking and cycling conditions and Transportation Demand Management factors fall into the high-priority strategies that impact on resident's behavior in city center of Sanandaj.
According to positive and negative qualities of the site and calculated prioprities for each factor, the key five strategic recommendations presented based on objectives. These are based on the aim of research that wants achieve sustainable center for Sanandaj. Strategic recommendations include change in density, management of land use, improving road networks condition, Strengthening the social dimension and identity of neighborhoods and Regeneration of old areas and Buildings with historical value.
Residents in sprawled area for access to daily services must be traveled to city center by vehicles that it causes some challenges. Hence in this paper after identifying practical principles of TOD and land use impacts on travel behavior in the study area, by use of paiwaise comparison in AHP method, important factors are identified. Therefore access to public transportation (0.266), TDM (0.195) and walk and bicycle conditions (0.123) have maximum effect on traveling pattern of residents. Hence first hypothesis of research proved. Then recommended plan presented for the area in form of practical strategies. Finally for achieving research objectives, recommended strategies provided that include Strengthening the social dimension and identity of neighborhoods, Regeneration of old areas and Buildings with historical value, Improving road networks condition, Development of sustainable and integrated transportation system, Changes in density and development of user friendly and public transport supportive land use. Above strategies based on main criteria of TOD planning affect on sustainable travel behavior of residents and also will have significant role in achieving to sustainable urban centers that is proving second hypothesis of the research.