Recolonización urbana.Nuevos fragmentos urbanos en las primeras periferias.

Abstract

Urban re-colonization researches the phenomenon of urban redevelopment that has focused the cleaning of pre-existing industrial sites, railway areas and ports in several early peripheries. In the last 25 years, it became a conviction that the city should be intervened by urban fragments, leading to the development of new planning, design and management instruments. Those mechanisms delimit strict perimeters of intervention, avoiding the reproduction of massive urban renewal actions of the first half of the 20th Century. However, as far as the urban fragment to be intervened grows in size, there is the risk that the design is self-contained, ignoring the context where it is placed. From this reflection emerges the hub of the research: understand and evaluate how those redeveloped urban fragments fit in their context, by analysing design strategies. That morphological focus requires the analysis of the relations established by the new urban fragment and the surrounding, either investigating how the adjacent areas and the pre-existing elements may orient the design, either understanding how the built-up form defined in the design dialogue with the context. Redevelopment profits from the opportunities existent in the early peripheries, territories developed in the second half of the 19th Century. The former elements in those peripheries that attracted new activities, in a second moment, started to function as obstacles to the link of the rising urban fabrics. Although the city continued to expand, those obstacles resisted in those territories, offering the present opportunities for redevelopment. Redevelopment acts over already urbanised areas, affecting their deep structure. This inner city transformation may be recognized as a process of re-colonization that reorganizes the built-up form, the support and the activities. The research identifies the spaces around the obstacles that represent opportunities of redevelopment the borders. Their transformation can help reconnecting grids historically segregated. The work analyses the topological relations between the area, the immediate surrounding and the pre-existing elements, in order to typify scenarios of urban design morphological scenarios. Deconstructing the design process, strategies used to define the support and three-dimensional patterns are identified. While the design of the support allows evaluating the integration and articulation of the new urban fragment in the context, the three-dimensional patterns help analysing the morphological coherence of this new space in relation to the existing surrounding. Those variables are used to verify to what degree the redeveloped areas where able to establish urban cohesion for territories historically characterized as fragmented, heterogeneous and disconnected. Cohesion is observed in designs that have reconstituted the morphological continuity between the new urban fragments and the surrounding area, by composing a grid which links the streets touching the perimeter of intervention. Also, cohesion is noticed in the fragments with well-configured open areas, where their urban function is clear and where flows are well-oriented. The role played by housing in those projects helps finding morphological coherence between new and old urban fabrics, due to the flexibility housing typologies assume. By rejecting self-contained urban compositions, some design strategies succeed in bringing positive effects for the redevelopment. Four territories are taken as examples in Barcelona (Poblenou), Paris (Quartier de la Gare), Amsterdam (Oostelijk Havengebied) and Rio de Janeiro (Enseada da Gamboa), where seven urban operations and eleven urban projects are developed. The theoretical dimension explored in the research of those recent experiences of urban redevelopment allows the construction of analytical tools that are converted, in the manner of conclusions, into a methodological approach for urban redevelopment projects.