An Investigation of concept of Subdivision in new urban Extensions (A Case Study: Zanjan Province)

Document Type : Research Article



Urban land subdivision is one of the important stages in urban extensions. The meaning of urban land subdivision is not restricted to dividing residential lands to plots and demonstrating frontage of lots only. The aims of this paper are representation of the new concept of urban land subdivision and investigation of the relationship between urban space quality and land subdivision. The quality of urban spaces has decreased in new residential neighborhoods. The criteria of urban spaces quality are classified based on urban design and planning theories. It seems that one of the reasons of construction of undesirable urban spaces is the partial understanding of the concept and process of land subdivision, since it is not mono-factored. In general, every concept in urbanism is multi-factored. The research method in this paper is qualitative and is based on investigating global successful cases in urban extension. Global successful residential extensions will be investigated and represented based on land subdivision principles. Resident satisfaction in three land subdivision patterns, "grid, cul de sac and grid-cul de sac" , will be investigated in three case studies. Karmandan (grid pattern), Olom paye (cul-de-sac pattern), Ansaria (grid-cul de sac pattern) are the case studies located in Zanjan Province. The questionnaire had 33 questions categorized in six groups of access, physical and spatial quality, safety, transportation, land use, recognition of neighborhood. Resident satisfaction in grid pattern was less than the two other patterns. Safety in grid pattern was less than the two other patterns, but access in grid pattern was more. In grid pattern, pedestrian access conflict with car is more than cul-de-sac pattern, so land subdivision patterns directly affect the quality of urban spaces in new urban extensions.  Land subdivision pattern is influential in the qualitative criteria of urban spaces such as access, safety, hierarchical open space. Fundamental factors are physical, cultural, biological, economic, and political, therefore, the concept of land subdivision should not be restricted to the physical aspect only.  Finally, suggestions will be given for increasing urban space quality based on urban land subdivision such as cohesive open spaces, mixed land use in edges, cul-de-sac access in residential land use, pedestrian access between blocks, shared semi public open spaces between residential blocks, variety in size, form and orientation of parcels, different gates for each neighborhoods for more visual readability in new urban extensions, use of hierarchical access networks rather than checkered networks for more pedestrian safety, use of small cohesive squares rather than large square, use of recreational facilities such as theatres, restaurants, cafes, cinemas, and libraries, hotels, and teenage meeting rooms, extending the usage of the square to night-time. Parking should be located in smaller areas closer to destinations, especially in higher density extensions and at local shops. They should preferably be located away from the street at the back of buildings. If parking lots are located at the front, a maximum of two rows of parking should be constructed. Parking structures should not dominate street frontages. Other suggestions include the effective separation of pedestrian and vehicular movement at a scale which encourages activity and pedestrian comfort. To maintain privacy, a minimal distance of 11 meters is needed, otherwise visual obstructing elements, such as trees, should be provided. Buildings should be constructed closer to the street so to increase pedestrian activity, reduce resident isolation, and foster pedestrian services such as retail outlets along streets connecting higher density extensions. Creating special public places would also help, as public spaces and public institutions are the focal point of community life. Public furniture should support the desired character of the space. Providing physical, visible and perceptual connectivity between cluster and linear open spaces, aligning the hard open space system and soft open space system with main public buildings, such as community centers or places of worship, and construction of public buildings in relation to formal public spaces and important movement routes are also beneficial. Hard open spaces should announce the buildings and accommodate informal activities that respond to these buildings. Locating symbolic and/or focal points in the middle of a cluster space or at the termination points of a linear space and continuation of special activities or functions that exist in the node and within the linkages towards the node are other suggestions