From The Urban Segregation To A Minimal Distance: Green Interstice as a Catalyst of Residential Transformation Aliaksandra Smirnova Polytechnic University of Catalonia, Barcelona, Spain
Abstract: The article focuses in studying of the role that green/empty areas have in structuring of the residential fragments. The pathology of the fragmented cities is found in the relationship between the built zone and the green/empty interstices. The interstitial space plays a structural role but do not generate any kind of urbanity. As a result, it is challenging to overcome physical segregation and urban and visual discontinuity between these adjacent areas. Therefore, the main question is: if the urban continuity is one of the keys to achieve a certain level of urbanity, in what way the segregation, provoked by green/empty interstices, can be reversed and converted into an element of urban articulation?
Keywords: fragmented cities, green/empty interstices, residential fragments, urban transformation
Nowadays it is necessary to redefine modernity. But how can we get there? Can we follow the same strategic line as the Modern Movement did: planning new towns and forgetting the past of the devastated cities? Is it possible to transform and modernize already urbanized areas to create a new urbanity? In the 1965, when C. Alexander published his article “City is not a tree”, it was already recognized that the modern city reached a critical point in its development and required some kind of redefinition. En his work C. Alexander defines two types of urban elements organization: the tree model and the semi-lattice model. The definition of this urban organization is established in his article as axioms [3; pp. 5].:
the tree axiom states: "A collection of sets forms a tree if, and only if, for
any two sets that belong to the collection, either one is wholly contained in the other, or else they are wholly disjoint";
the semi-lattice axiom goes like this: "A collection of sets forms a semi-lattice
if and only if, when two overlapping sets belong to the collection, then the set of elements common to both also belongs to the collection".
Applying these statements at the urban areas it can be said that the tree system, which was represented in modern city, did not respond to the needs of the moment and had to be
transformed into a semi-lattice system. Nevertheless, a lot of current cities still maintain the tree system character: road hierarchy and specialization, urban zoning and functional segregation. Therefore, we are dealing with fragmented cities, where the urban elements, functions and scales are not interrelated. One of the paradigmatic examples of this type of urban organization is a case of Minsk, Belarus. It was almost completely destroyed after the World War II and rebuilt under the Modern Movement concepts. According to the new general plan, it was established a new urban model based in a radio-central system with high functional road hierarchy and strict zoning. Currently, the urban structure of Minsk consists in three road rings, which establish in the hierarchical order the urban areas depending on the distance from the city center. In the same time, it is paid a lot of attention in developing of the continuous green system that is configured by the fluvial corridors of the city. The urban self-sufficient fragments are composed according to the road and green areas structure and based in the “microraion” urban scheme built by residential blocks. In other words, the city structure is organized according to the pyramidal order: all its urban elements (road system, green corridors, residential and industrial fragments, urban centers) are hierarchically organized according to the paper that they play in the city structuring [fig.1]. In particular, this urban organization is found in the residential fragments where the empty interstitial space has a structural role but do not generate any kind of urbanity. As a result, it is challenging to overcome physical segregation and urban and visual discontinuity between adjacent areas. These interstitial spaces are fruits of the urban proposals: “…that work as a collection of autonomous buildings (urban fragments) that share a common ground that organizes the site” [1; pp. 169]. In this way, the urban fragment presents a sum of the isolated parts of the cities.
Figure 3. The scheme of the fragmented urban structure of Minsk, developed by author
If the urban continuity is one of the keys to achieve a certain level of urbanity, in what way can we reverse this segregation and convert it into an element of urban articulation? The study takes as an example a case of one of the sleeping district of Minsk (Zeleniy Lug), which presents the mentioned above fragmented city structure in its pure form: the independent urban fragments articulated by the elaborated road system and continuous green corridors that occupy interstitial areas [fig. 2].
Figure 2. The green interstice as a segregating element (Zeleniy Lug district, Minsk) developed by author
One of the fundamental tactic of the urban intervention is utilization of the induction method instead the deduction. In other words, to use the bottom-up scheme, to work from the specific to the general and to act on the inter-medial scale: “…that will serve us as a support to subsequently pass to the larger scale and do not acting in the contrariwise way as it’s performed in nowadays [7, Manuel de Solá-Morales; pp. 14]. “This approach accepts working at the scale of the urban fragment, with the understanding that an intervention can use this starting point to address the general issues of a city” [1; pp. 149]. Applying the induction strategy in the studies' case the following question arises: in which way it has to be intervened on the interstitial space to convert it into an integrated element which would be capable to provoke changes in the adjacent patterns and increase the urbanity level? The green/empty interstice it is not only a structural element but also can has the catalytic properties. Therefore, the urban transformation strategies have to be based on the intentional intervention on the interstitial space. In the following it will be proposed some actuation tactics.
The first step is the organization of the connection bridges which will link the urban fragments with green/empty interstice: this kind of actuation can help to create exchange points between two different scales: domestic scale (residential fragments) and urban scale (green interstice). In the moment of disposing of the connection bridges it can be possible to work with a limit between the urban fragment and green/empty interstices. Via the connection bridges is established some intersections between two segregated elements (built zone and green interstice). These intersections are important ingredient for the creation of urban corners: “…that materialize agreement and contrasts between building and persons, activities and movements” [2; pp. 50]. According to Manuel de Solá-Morales in the modern city the corners are no longer the stone corners. In the present days a new type of the corners is creating, which materializes in railway stations, parking, big equipment, terminals, intercoolers and nodes of the transport. [2; pp. 40]. In consequence, the connection bridges not only increase the mobility level, but they also have a capability to generate a new type of the urban corners. Afterwards the achievement of the certain connection level between residential fragments and green/empty zones, it can be start to fill these unused and worthless interstitial areas. The emphasis is made in the fact that the interstice space in the moment of the planning was thought as a public space, thus it has a potential to comply with this role. Nevertheless, it is necessary to keep in mind that: “…today public space must go beyond its purely civic presence. It must be programmed to attract a large number of users and to activate its surroundings at different times of day” [1; pp. 142]. Through this medium it is possible to achieve two objectives: to relive the interstitial space by its transformation from the abandoned zones into a public space and provoke the activation of the contiguous residential areas [fig. 3].
Figure 3. Integration of the green interstice into the built area developed by author
Nevertheless, it cannot be forgotten that this type of intervention is not about the occupying the empty space by some definitive objects: “…the city has to maintain it (empty spaces) without any kind of constructive speculation and assume it as strategy areas” [5; p. 1]. The unoccupied or open space has a great relevance in the definition of its (of the city) form” [4; pp. 100]. Applying established in the J. Florit's PhD Thesis metropolitan parks' properties1 to the green interstitial spaces, it can be possible to transform them into a unique element of the great value from the urban point of view. In this way, the empty and abandoned zones have an opportunity to be converted into: “…areas prepared for being constantly reinvented, potentially able to be used in thousand ways and always willing to host events in the outgoing construction of the city” [5; pp. 13]. Through the implementation of the proposed strategies it is possible to improve the urbanity level in the residential fragments. By the transformation of the green/empty interstices into a public space and creating encounter points between urban elements, it is possible to generate collaboration between early segregated areas by overlapping its properties. By this route, it is possible to achieve that the organization of the urban fragments lies ahead to the semilattice system established by C. Alexander. This manner to understand the city makes reference to the Manuel de Solá-Morales view: “A good approach would be an approach to the city "through their stuff", from the materials that actually build the city…by recognizing of the territory (city, urban fragment) as the related to each other sum of things” .
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