4_From-maximum-urban-porosity-to-city-s-disaggregation--Evidence-fro_2024_Citi

Urban Porosity and Its Erosion

  • Porosity in Urban Context

    • Refers to soft transitions between different urban spaces and the interpenetration of distinct urban functions.

    • Absence of porosity is noticeable in post-modern urban designs.

  • Objectives of Research

    • To resettle the concept of porosity in urban planning.

    • To identify and explain the circumstances that have led to urban porosity erosion.

  • Key Concepts Established

    • Define urban and architectural porosity and the criteria to evaluate each.

    • Explore the implications of modernist principles on urban planning and porosity.

    • Compare urban porosity in five Lisbon neighborhoods across different historical contexts.

Historical Context of Urban Porosity

  • Origin of the term

    • Introduced by Benjamin and Lacis in 1925 to describe Naples, a city characterized by overlapping spaces.

    • Porosity fosters a sense of community and encourages unexpected interactions.

  • Recent Perspectives

    • Modern urban design has contributed to the decline of porosity.

    • Notable authors on the topic: Jacobs, Gehl, and Sennett, focusing on walkability and social cohesion.

The Importance of Urban Porosity

  • Benefits Associated with Porosity

    • Fosters stronger communities and better health outcomes.

    • Promotes empathy and tolerance across diverse populations.

    • Enhanced walkability leads to increased physical activity and improved mental health.

  • Influences on Urban Design

    • Modernist approaches segregated urban functions, leading to less porous landscapes.

    • Urban barriers from modernist developments inhibit flow and accessibility in urban spaces.

Literature Review

  • Conceptual Foundations

    • Porosity includes physical and social aspects, impacting both urban space and social dynamics.

    • Sennett's idea of perforated borders as connectors between diverse spaces.

  • Criteria for Porosity

    • Urban Porosity: Connected streets, diverse public spaces, walkable neighborhoods, and short diverse built forms.

    • Architectural Porosity: Dense-low structure, active building edges, communal functionality, and inviting public spaces.

Methodology of Investigation

  • Research Framework

    • Qualitative and quantitative methods to evaluate porosity in urban settings.

    • Selection of five Lisbon neighborhoods to illustrate changes in urban morphology.

  • Neighborhood Selection:

    1. Bairro Alto (Historical)

    2. Campo de Ourique (Traditional)

    3. Alvalade (Conservative Modernism)

    4. Chelas (Modernist)

    5. Galhardas (Contemporary)

Comparative Analysis of Neighborhoods

  • Findings

    • Bairro Alto: Highest porosity but with poor living conditions.

    • Campo de Ourique: Balance of density, ensemble diversity, and walkability.

    • Alvalade: Exemplifies conservative modernist architecture with some porosity qualities.

    • Chelas & Galhardas: Show marked decline in porosity, leading to social isolation and inactivity.

Conclusions and Recommendations

  • Radical Loss of Porosity

    • Modernist principles perpetuated an erosion of urban and architectural porosity.

    • Need for updated urban legislation to enhance porosity in future developments.

  • Future Research Directions

    • Continued exploration of porosity within different urban contexts.

    • Establishing practical metrics and criteria relevant to urban planning and community integration.