A Grammar-Based Optimization Approach for Designing Urban Fabrics and Locating Amenities for 15-Minute Cities

Abstract

Providing pedestrian accessibility to urban services is a big challenge and a key factor in creating more walkable urban areas. Moreover, it is a critical aspect of climate-resilient urban planning as it is broadly assumed that neighborhoods with greater walkability discourage automobile use and reduce CO2 emissions. The idea of 15-minute cities, defined as urban environments where most places that residents need to access are within a 15-minute walk, is gaining increasing attention worldwide. Because aspects of urban performance are increasingly quantifiable, generative, and data-driven design approaches can explore broader sets of potential solutions, while optimization can help identify designs with desired properties. This work demonstrates and tests a new approach that combines shape grammars, a formal method for shape generation that facilitates the elaboration of complex patterns and meaningful solutions, with multi-objective optimization. The goal was to optimize the design of urban fabric layouts and the location of amenities to provide 15-minute neighborhood configurations that minimize infrastructure cost (as estimated by cumulative street length) and the number of amenities, while maximizing pedestrian accessibility to urban services (as assessed by overall integration and the average distance from all plots to nearest amenities).

Smart Cities and Urban Energy Planning: An Advanced Review of Promises and Challenges

“…DTs and simulation software, leveraging data from mobile devices and IoT sensors, enable the modeling of commuting behaviors and energy consumption patterns, informing land use and transportation policies [88,89]. These tools also support the implementation of recent urban development concepts such as "15-min city", utilizing generative planning and technologies such as 6G and IoT to optimize the placement of amenities and improve city connectivity [90][91][92]. Additionally, the integration of GIS with Building Information Modeling (BIM) allows for the comparison of energy performance across urban development scenarios [3,4,93].…”

The Fractal Approach in the Biomimetic Urban Design: Le Corbusier and Patrick Schumacher

“…They support the discovery of designs within an existing design language by providing tools to identify their generation or production of new design languages. Although their use is more prominent in architecture, shape grammars are increasingly used at the urban design scale due to software and hardware improvements that support their use for flexible urban planning [47,48].…”

Digital Form Generation of Heritages in Historical District Based on Plan Typology and Shape Grammar: Case Study on Kulangsu Islet

“…In this context, shape grammar started to be applied to the analysis and generation of digital models. The studies cover scales of city, architecture, and landscape, while the research on city scale focuses on urban plots, roads, interfaces, and other content, as well as parameters such as distances, widths, and angles of urban blocks, and finally forms software or tools to guide urban design [48][49][50][51][52]. With similar analytical logic in architecture and traditional architectural diagramming and semantic analysis, shape grammar is a method of abstract diagramming.…”