Concentration Block: Multiple Hybridization in the Fragmentary City Part 2 Project 2008 Eduardo Parra Chavarro National University of Colombia - Bogotá campus | Colombia The Metropolis will become the major event of human concentration in history and the colossal dimensions that some of them have reached make their evolution even more unviable in a global context that emphasizes the need for a rational use of the energies and the elimination of the social conflicts expressed in the configuration of the city.The sprawl urban expansion disables the optimization of collective transport systems, increases the city building costs, magnifies the social fracture in the territory and intensifies the environmental emergency caused by the gases of vehicles that carry out extensive itineraries. The hybrid project responds to these problems with more population density and typological diversity in housing as a reflection of social diversity, more presence and richness of urban program to endow it with metropolitan character, and better environmental considerations.If the city is formally fragmentary, the block is a sum of parts; if the city grows horizontally undetermined, the block grows vertically to the point of definition; if the city holds within a social fracture, the block summons the social diversity; if in the city the property model is stationary and sedentary, in the block is dynamic and nomad; if the city promotes a high level of contamination and energetic squandering, the block makes of sustainability its principal added value.The hybrid program is gathered in a tower that stands out of the earth as a cube with two housing blocks oriented for solar light improvement, connected with suspended beams that lodge collective services, and by a green fold oriented to the south, like a plant searching for sun light, as space of encounter. A park is located as coronation with eolic generators that feed the hybrid of energy. The project has six floors beneath street level dedicated to parking and leisure activities.Beyond a spatial proposal, it represents a new “urban breed” with new forms of social relations. The housing designs merge with a dynamic property model; users acquire spaces targeted to specific times of the inhabitant´s life, moving to another typology as soon their needs evolve.A Utopia for the Contemporary City. Eduardo Parra Chavarro The “Concentration Block” is a research to rethink and a project to rebuild the contemporary notions of city, architecture and society. Through the acknowledgment of the diversity and complexity of contemporary societies, and the recognition of new living practices and family structures, the project calls for a social reconstitution, within a process of densification proposed for achieving environmental and economic sustainability. It´s a concrete intervention product of a framework that thinks globally about the urban conditions of the fragmentary city imagined like a web of metropolitan relations. The study and critical analysis of the contemporary city becomes the best “breeding ground” to create the hybrid project, which is materialized in a strategic urban block of the city center. It´s conceived like the ideal solution of what the basic urban cell should be justified by a framework that identifies the negative (environmental, social and economic) aspects of urban dispersion. Its “utopian” nature is also explicit when it doesn´t respond to the particular urban normativities, because they are always exceeded by the shifting requirements of the city.The proposal is a typological transformation of the obsolescent urban block imagined like a collection of individual interventions. The urban block is now created like a single architectural entity made out of pieces that respond naturally to the surrounding urban and climate conditions. An entity where society becomes architecture and architecture becomes city. The private housing of architectural scale next to metropolitan public activities of urban scale, is a example of the hybridization of programs, forms and social structures of different nature that display the mixture of the characteristic contradictions of the contemporary world, that finds in the city the best stage to be performed. Hybrid architectures, like their nature counterparts, become long-lasting and stronger entities that are better equipped to face the upcoming challenges of urban dynamic logics.Finally, it´s important to reaffirm the absolute coherence between theoretical approach and architectural solution, achieving a symphony between theory and practice like no other. Nevertheless, it cannot be considered a closed and finished exercise, but the beginning of a path for research, innovation and personal fulfillment.